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[[File:Oxygen piping.png|thumb|right|Oxygen piping and regulator with flow meter, for oxygen therapy, mounted in an [[ambulance]]]]
[[File:Oxygen piping.png|thumb|right|Oxygen piping and regulator with flow meter, for oxygen therapy, mounted in an [[ambulance]]]]
[[File:o2regulator.JPG|thumb|right|Oxygen Regulator for portable D-Cylinder, usually carried in an ambulance's resuscitation kit.]]
[[File:o2regulator.JPG|thumb|right|Oxygen Regulator for portable D-Cylinder, usually carried in an ambulance's resuscitation kit.]]
'''Oxygen therapy''' is the administration of [[oxygen]] as a medical intervention, which can be for a variety of purposes in both [[Chronic (medicine)|chronic]] and [[Acute (medicine)|acute]] patient care. Oxygen is essential for [[Cell (biology)|cell]] metabolism, and in turn, tissue oxygenation is essential for all normal physiological functions.<ref name=jrcalc>{{cite web|publisher=Joint Royal Colleges Ambulance Liaison Committee/Warwick University|title=Clinical Guidelines Update — Oxygen|date=April 2009|url=http://www2.warwick.ac.uk/fac/med/research/hsri/emergencycare/prehospitalcare/jrcalcstakeholderwebsite/clinicalpracticeupdates/oxygen_guideline_combined_final_published_version_22apr09sb.pdf|accessdate=2009-06-29}}</ref>
'''Oxygen therapy''' is the administration of [[oxygen]] as a medical intervention, which can be for a variety of purposes in both [[Chronic (medicine)|chronic]] and [[Acute (medicine)|acute]] patient care. Oxygen is essential for [[Cell (biology)|cell]] metabolism, and in turn, tissue oxygenation is essential for all normal physiological functions.<ref name=jrcalc>{{cite web|publisher=Joint Royal Colleges Ambulance Liaison Committee/Warwick University|title=Clinical Guidelines Update — Oxygen|date=April 2009|url=http://www2.warwick.ac.uk/fac/med/research/hsri/emergencycare/prehospitalcare/jrcalcstakeholderwebsite/clinicalpracticeupdates/oxygen_guideline_combined_final_published_version_22apr09sb.pdf|accessdate=2009-06-29}}</ref>


High blood and tissue levels of oxygen can be helpful or damaging, depending on circumstances and oxygen therapy should be used to benefit the patient by increasing the supply of oxygen to the [[lungs]] and thereby increasing the availability of oxygen to the [[body tissue]]s, especially when the patient is suffering from [[Hypoxia (medical)|hypoxia]] and/or [[hypoxaemia]].
High blood and tissue levels of oxygen can be helpful or damaging, depending on circumstances and oxygen therapy should be used to benefit the patient by increasing the supply of oxygen to the [[lungs]] and thereby increasing the availability of oxygen to the [[body tissue]]s, especially when the patient is suffering from [[Hypoxia (medical)|hypoxia]] and/or [[hypoxaemia]].


==Indications for use==
==Indications for use==
Oxygen is used as a medical treatment in both chronic and acute cases, and can be used in [[hospital]], pre-hospital or entirely out of hospital, dependent on the needs of the patient and their medical professionals' opinions.
Oxygen is used as a medical treatment in both chronic and acute cases, and can be used in hospital, pre-hospital or entirely out of hospital, dependent on the needs of the patient and their medical professionals' opinions.


===Use in chronic conditions===
===Use in chronic conditions===
A common use of supplementary oxygen is in patients with [[chronic obstructive pulmonary disease]] (COPD), the occurrence of chronic bronchitis or emphysema, a common long term effect of [[smoking]], who may require additional oxygen to breathe either during a temporary worsening of their condition, or throughout the day and night. It is indicated in COPD patients with Pa{{chem|O|2}} ≤ 55mmHg or Sa{{chem|O|2}} ≤ 88% and has been shown to increase lifespan.<ref>{{cite journal|journal=The Medical Journal of Australia |title=Adult domicilariary oxygen. Position statement of the Thoracic Society of Australia and New Zealand|volume=182|issue=12|pages=621–6|year=2005 |last1=McDonald |first1=Christine F |last2=Crockett |first2=Alan J |last3=Young |first3=Iven H |url=http://www.mja.com.au/public/issues/182_12_200605/mcd10865_fm.html}}</ref><ref name="Stoller-2010">{{Cite journal | last1 = Stoller | first1 = JK. | last2 = Panos | first2 = RJ. | last3 = Krachman | first3 = S. | last4 = Doherty | first4 = DE. | last5 = Make | first5 = B. | title = Oxygen therapy for patients with COPD: current evidence and the long-term oxygen treatment trial. | journal = Chest | volume = 138 | issue = 1 | pages = 179-87 | date= Jul 2010 | doi = 10.1378/chest.09-2555 | PMID = 20605816 }}</ref><ref name="-1980">{{Cite journal | title = Continuous or nocturnal oxygen therapy in hypoxemic chronic obstructive lung disease: a clinical trial. Nocturnal Oxygen Therapy Trial Group. | journal = Ann Intern Med | volume = 93 | issue = 3 | pages = 391-8 | date= Sep 1980 | doi = 10.7326/0003-4819-93-3-391| PMID = 6776858 }}</ref>
A common use of supplementary oxygen is in patients with [[chronic obstructive pulmonary disease]] (COPD), the occurrence of chronic bronchitis or emphysema, a common long term effect of smoking, who may require additional oxygen to breathe either during a temporary worsening of their condition, or throughout the day and night. It is indicated in COPD patients with Pa{{chem|O|2}} ≤ 55mmHg or Sa{{chem|O|2}} ≤ 88% and has been shown to increase lifespan.<ref>{{cite journal|journal=The Medical Journal of Australia |title=Adult domicilariary oxygen. Position statement of the Thoracic Society of Australia and New Zealand|volume=182|issue=12|pages=621–6|year=2005 |last1=McDonald |first1=Christine F |last2=Crockett |first2=Alan J |last3=Young |first3=Iven H |url=http://www.mja.com.au/public/issues/182_12_200605/mcd10865_fm.html}}</ref><ref name="Stoller-2010">{{Cite journal | last1 = Stoller | first1 = JK. | last2 = Panos | first2 = RJ. | last3 = Krachman | first3 = S. | last4 = Doherty | first4 = DE. | last5 = Make | first5 = B. | title = Oxygen therapy for patients with COPD: current evidence and the long-term oxygen treatment trial. | journal = Chest | volume = 138 | issue = 1 | pages = 179–87 | date= Jul 2010 | doi = 10.1378/chest.09-2555 | PMID = 20605816 }}</ref><ref name="-1980">{{Cite journal | title = Continuous or nocturnal oxygen therapy in hypoxemic chronic obstructive lung disease: a clinical trial. Nocturnal Oxygen Therapy Trial Group. | journal = Ann Intern Med | volume = 93 | issue = 3 | pages = 391–8 | date= Sep 1980 | doi = 10.7326/0003-4819-93-3-391| PMID = 6776858 }}</ref>


Oxygen is often prescribed for people with [[breathlessness]], in the setting of end-stage cardiac or respiratory failure, advanced cancer or neurodegenerative disease, despite having relatively normal blood oxygen levels. A 2010 trial of 239 subjects found no significant difference in reducing breathlessness between oxygen and air delivered in the same way.<ref name="Abernethy2010">{{cite journal |last=Abernethy |first=Amy |coauthors=McDonald, CF; Frith, PA; Clark, K; Herndon, JE 2nd; Marcello, J; Young, IH; Bull, J; Wilcock, A; Booth, S; Wheeler, JL; Tulsky, JA; Crockett, AJ; Currow, DC |title=Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: a double-blind, randomised controlled trial |journal=Lancet |date=4 September 2010 |volume=376 |issue=9743 |pages=784–793 |doi=10.1016/S0140-6736(10)61115-4 |pmid=20816546 |pmc=2962424}}</ref>
Oxygen is often prescribed for people with [[breathlessness]], in the setting of end-stage cardiac or respiratory failure, advanced cancer or neurodegenerative disease, despite having relatively normal blood oxygen levels. A 2010 trial of 239 subjects found no significant difference in reducing breathlessness between oxygen and air delivered in the same way.<ref name="Abernethy2010">{{cite journal |last=Abernethy |first=Amy |coauthors=McDonald, CF; Frith, PA; Clark, K; Herndon, JE 2nd; Marcello, J; Young, IH; Bull, J; Wilcock, A; Booth, S; Wheeler, JL; Tulsky, JA; Crockett, AJ; Currow, DC |title=Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: a double-blind, randomised controlled trial |journal=Lancet |date=4 September 2010 |volume=376 |issue=9743 |pages=784–793 |doi=10.1016/S0140-6736(10)61115-4 |pmid=20816546 |pmc=2962424}}</ref>
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It may also be indicated for any other patient where their injury or illness has caused [[hypoxaemia]], although in this case oxygen flow should be moderated to achieve target [[oxygen saturation]] levels, based on [[pulse oximetry]] (with a target level of 94–98% in most patients, or 88–92% in COPD patients).<ref name=jrcalc/>
It may also be indicated for any other patient where their injury or illness has caused [[hypoxaemia]], although in this case oxygen flow should be moderated to achieve target [[oxygen saturation]] levels, based on [[pulse oximetry]] (with a target level of 94–98% in most patients, or 88–92% in COPD patients).<ref name=jrcalc/>


For personal use, high concentration oxygen is used as home therapy to abort [[cluster headache]] attacks, due to its vaso-constrictive effects.<ref>{{cite web |url= http://www.headaches.org/consumer/topicsheets/oxygen.html |title= Oxygen Therapy for Headaches|accessdate=2007-11-26 |first= George |last=Sands}}</ref>
For personal use, high concentration oxygen is used as home therapy to abort [[cluster headache]] attacks, due to its vaso-constrictive effects.<ref>{{cite web |url= http://www.headaches.org/consumer/topicsheets/oxygen.html |title= Oxygen Therapy for Headaches|accessdate=2007-11-26|first= George |last=Sands}}</ref>


Patients who are receiving oxygen therapy for hypoxemia following an acute illness or hospitalization should not routinely have a prescription renewal for continued oxygen therapy without a physician's re-assessment of the patient's condition.<ref name="ACCPandATSfive">{{Citation |author1 = American College of Chest Physicians |author1-link = American College of Chest Physicians |author2 = American Thoracic Society |author2-link = American Thoracic Society |date = September 2013 |title = Five Things Physicians and Patients Should Question |publisher = American College of Chest Physicians and American Thoracic Society |work = [[Choosing Wisely]]: an initiative of the [[ABIM Foundation]] |page = |url = http://www.choosingwisely.org/doctor-patient-lists/american-college-of-chest-physicians-and-american-thoracic-society/ |accessdate = 6 January 2013}}, which cites
Patients who are receiving oxygen therapy for hypoxemia following an acute illness or hospitalization should not routinely have a prescription renewal for continued oxygen therapy without a physician's re-assessment of the patient's condition.<ref name="ACCPandATSfive">{{Citation |author1 = American College of Chest Physicians |author1-link = American College of Chest Physicians |author2 = American Thoracic Society |author2-link = American Thoracic Society |date = September 2013 |title = Five Things Physicians and Patients Should Question |publisher = American College of Chest Physicians and American Thoracic Society |work = [[Choosing Wisely]]: an initiative of the [[ABIM Foundation]] |page = |url = http://www.choosingwisely.org/doctor-patient-lists/american-college-of-chest-physicians-and-american-thoracic-society/ |accessdate = 2013-01-06}}, which cites
*{{Cite journal
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| title = Long-term Oxygen Treatment in Chronic Obstructive Pulmonary Disease: Recommendations for Future Research
| title = Long-term Oxygen Treatment in Chronic Obstructive Pulmonary Disease: Recommendations for Future Research
| journal = American Journal of Respiratory and Critical Care Medicine
| journal = American Journal of Respiratory and Critical Care Medicine
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| last4 = British Thoracic | first4 = S.
| title = BTS guideline for emergency oxygen use in adult patients
| title = BTS guideline for emergency oxygen use in adult patients
| doi = 10.1136/thx.2008.102947
| doi = 10.1136/thx.2008.102947
| journal = Thorax
| journal = Thorax
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| title = Prescription of Oxygen
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| doi = 10.1164/rccm.2506007
| journal = American Journal of Respiratory and Critical Care Medicine
| journal = American Journal of Respiratory and Critical Care Medicine
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| pmc =
}}</ref> If the patient has recovered from the illness, then the hypoxemia is expected to resolve and additional care would be unnecessary and a waste of resources.<ref name="ACCPandATSfive"/>
}}</ref> If the patient has recovered from the illness, then the hypoxemia is expected to resolve and additional care would be unnecessary and a waste of resources.<ref name="ACCPandATSfive"/>
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==Storage and sources==
==Storage and sources==
[[File:Home oxygen cannisters.jpg|thumb|Gas cylinders containing oxygen to be used at home. When in use a pipe is attached to the cylinder's regulator and then to a mask that fits over the patient's nose and mouth.]]
[[File:Home oxygen cannisters.jpg|thumb|Gas cylinders containing oxygen to be used at home. When in use a pipe is attached to the cylinder's regulator and then to a mask that fits over the patient's nose and mouth.]]
[[File:Home oxygen concentrator.jpg|thumb|A home oxygen concentrator ''in situ'' in an [[emphysema]] patient's house.]]Oxygen can be separated by a number of methods, including [[chemical reaction]] and [[fractional distillation]], and then either used immediately or stored for future use. The main types sources for oxygen therapy are:
[[File:Home oxygen concentrator.jpg|thumb|A home oxygen concentrator ''in situ'' in an [[emphysema]] patient's house.]]Oxygen can be separated by a number of methods, including [[chemical reaction]] and [[fractional distillation]], and then either used immediately or stored for future use. The main types sources for oxygen therapy are:
#Liquid storage — [[Liquid oxygen]] is stored in chilled tanks until required, and then allowed to [[boiling|boil]] (at a temperature of 90.188 K (−182.96 °C)) to release oxygen as a gas. This is widely used at hospitals due to their high usage requirements, but can also be used in other settings. See [[Vacuum Insulated Evaporator]] for more information on this method of storage.
#Liquid storage — [[Liquid oxygen]] is stored in chilled tanks until required, and then allowed to [[boiling|boil]] (at a temperature of 90.188 K (−182.96&nbsp;°C)) to release oxygen as a gas. This is widely used at hospitals due to their high usage requirements, but can also be used in other settings. See [[Vacuum Insulated Evaporator]] for more information on this method of storage.
#Compressed gas storage — The oxygen gas is compressed in a [[gas cylinder]], which provides a convenient storage, without the requirement for refrigeration found with liquid storage. Large oxygen cylinders hold {{convert|6500|l|cuft}} and can last about two days at a flow rate of 2&nbsp;litres per minute. A small portable M6 (B) cylinder holds {{convert|164|or|170|l|cuft}} and weighs about {{convert|1.3|to|1.6|kg|lb}}.<ref name="cprsavers">{{cite web |url=http://www.cpr-savers.com/Industrials/oxygen%20supply/luxfer-oxygen-cylinder-tanks.html |title=Luxfer Aluminum Oxygen Cylinders |publisher=CPR Savers & First Aid Supply |accessdate=18 April 2010}}</ref> These tanks can last 4–6 hours when used with a conserving regulator, which senses the patient's breathing rate and sends pulses of oxygen. Conserving regulators may not be usable by patients who breathe through their mouths.
#Compressed gas storage — The oxygen gas is compressed in a [[gas cylinder]], which provides a convenient storage, without the requirement for refrigeration found with liquid storage. Large oxygen cylinders hold {{convert|6500|l|cuft}} and can last about two days at a flow rate of 2&nbsp;litres per minute. A small portable M6 (B) cylinder holds {{convert|164|or|170|l|cuft}} and weighs about {{convert|1.3|to|1.6|kg|lb}}.<ref name="cprsavers">{{cite web |url=http://www.cpr-savers.com/Industrials/oxygen%20supply/luxfer-oxygen-cylinder-tanks.html |title=Luxfer Aluminum Oxygen Cylinders |publisher=CPR Savers & First Aid Supply |accessdate=2010-04-18}}</ref> These tanks can last 4–6&nbsp;hours when used with a conserving regulator, which senses the patient's breathing rate and sends pulses of oxygen. Conserving regulators may not be usable by patients who breathe through their mouths.
#Instant usage — The use of an electrically powered [[oxygen concentrator]]<ref>{{cite web |url= http://www.inspiredrc.com/POC%20AARC%20Dec%202006.pdf |title= Portable Oxygen Concentrators (POC) Performance Variables that Affect Therapy|accessdate=2007-07-03 |format= pdf |first= Robert |last=McCoy}}</ref> or a chemical reaction based unit<ref>[http://www.wemjournal.org/wmsonline/?request=get-document&issn=1080-6032&volume=013&issue=04&page=0253 Evaluation of the System O2 Inc Portable Nonpressurized Oxygen Delivery System]</ref> can create sufficient oxygen for a patient to use immediately, and these units (especially the electrically powered versions) are in widespread usage for home oxygen therapy and portable personal oxygen, with the advantage of being continuous supply without the need for additional deliveries of bulky cylinders.
#Instant usage — The use of an electrically powered [[oxygen concentrator]]<ref>{{cite web |url= http://www.inspiredrc.com/POC%20AARC%20Dec%202006.pdf |title= Portable Oxygen Concentrators (POC) Performance Variables that Affect Therapy|accessdate=2007-07-03|format= pdf |first= Robert |last=McCoy}}</ref> or a chemical reaction based unit<ref>[http://www.wemjournal.org/wmsonline/?request=get-document&issn=1080-6032&volume=013&issue=04&page=0253 Evaluation of the System O2 Inc Portable Nonpressurized Oxygen Delivery System]</ref> can create sufficient oxygen for a patient to use immediately, and these units (especially the electrically powered versions) are in widespread usage for home oxygen therapy and portable personal oxygen, with the advantage of being continuous supply without the need for additional deliveries of bulky cylinders.


==Delivery==
==Delivery==
Various devices are used for administration of oxygen. In most cases, the oxygen will first pass through a [[pressure regulator]], used to control the high pressure of oxygen delivered from a cylinder (or other source) to a lower pressure. This lower pressure is then controlled by a [[flowmeter]], which may be preset or selectable, and this controls the flow in a measure such as litres per minute (lpm). The typical flowmeter range for medical oxygen is between 0 and 15 lpm with some units able to obtain up to 25 liters per minute. Many wall flowmeters using a [[Thorpe tube flowmeter|Thorpe tube]] design are able to be dialed to "flush" which is beneficial in emergency situations.
Various devices are used for administration of oxygen. In most cases, the oxygen will first pass through a [[pressure regulator]], used to control the high pressure of oxygen delivered from a cylinder (or other source) to a lower pressure. This lower pressure is then controlled by a [[flowmeter]], which may be preset or selectable, and this controls the flow in a measure such as litres per minute (lpm). The typical flowmeter range for medical oxygen is between 0 and 15 lpm with some units able to obtain up to 25&nbsp;liters per minute. Many wall flowmeters using a [[Thorpe tube flowmeter|Thorpe tube]] design are able to be dialed to "flush" which is beneficial in emergency situations.


===Supplemental oxygen===
===Supplemental oxygen===
Many patients require only a supplementary level of oxygen in the room air they are breathing, rather than pure or near pure oxygen,<ref>{{harvnb|Kallstrom|2002}}</ref> and this can be delivered through a number of devices dependent on the situation, flow required and in some instances patient preference.
Many patients require only a supplementary level of oxygen in the room air they are breathing, rather than pure or near pure oxygen,<ref>{{harvnb|Kallstrom|2002}}</ref> and this can be delivered through a number of devices dependent on the situation, flow required and in some instances patient preference.


A [[nasal cannula]] (NC) is a thin tube with two small nozzles that protrude into the patient's nostrils. It can only comfortably provide oxygen at low flow rates, 2–6 litres per minute (LPM), delivering a concentration of 24–40%.
A [[nasal cannula]] (NC) is a thin tube with two small nozzles that protrude into the patient's nostrils. It can only comfortably provide oxygen at low flow rates, 2–6&nbsp;litres per minute (LPM), delivering a concentration of 24–40%.


There are also a number of face mask options, such as the [[simple face mask]], often used at between 5 and 8 LPM, with a concentration of oxygen to the patient of between 28% and 50%. This is closely related to the more controlled [[air-entrainment masks]], also known as Venturi masks, which can accurately deliver a predetermined oxygen concentration to the trachea up to 40%.
There are also a number of face mask options, such as the [[simple face mask]], often used at between 5 and 8 LPM, with a concentration of oxygen to the patient of between 28% and 50%. This is closely related to the more controlled [[air-entrainment masks]], also known as Venturi masks, which can accurately deliver a predetermined oxygen concentration to the trachea up to 40%.


In some instances, a partial rebreathing mask can be used, which is based on a simple mask, but featuring a reservoir bag, which increases the provided oxygen concentration to 40–70% oxygen at 5 to 15 LPM.
In some instances, a partial rebreathing mask can be used, which is based on a simple mask, but featuring a reservoir bag, which increases the provided oxygen concentration to 40–70% oxygen at 5 to 15 LPM.
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Non-rebreather masks draw oxygen from an attached reservoir bags, with one-way valves that direct exhaled air out of the mask. When properly fitted and used at flow rates of 8-10 LPM or higher, they deliver close to 100% oxygen. This type of mask is indicated for acute medical emergencies.
Non-rebreather masks draw oxygen from an attached reservoir bags, with one-way valves that direct exhaled air out of the mask. When properly fitted and used at flow rates of 8-10 LPM or higher, they deliver close to 100% oxygen. This type of mask is indicated for acute medical emergencies.


[[Demand valves]] or [[oxygen resuscitators]] deliver oxygen only when the patient inhales, or, in the case of an apnic (non-breathing) victim, the caregiver presses a button on the mask. These systems greatly conserve oxygen compared to steady-flow masks, which is useful in emergency situations when a limited supply of oxygen is available and there is a delay in transporting the patient to higher care. They are very useful in performing [[CPR]], as the caregiver can deliver rescue breaths composed of 100% oxygen with the press of a button. Care must be taken not to over-inflate the patient's lungs, and some systems employ safety valves to help prevent this. These systems may not be appropriate for unconscious patients or those in respiratory distress, because of the effort required to breathe from them.
[[Demand valves]] or [[oxygen resuscitators]] deliver oxygen only when the patient inhales, or, in the case of an apnic (non-breathing) victim, the caregiver presses a button on the mask. These systems greatly conserve oxygen compared to steady-flow masks, which is useful in emergency situations when a limited supply of oxygen is available and there is a delay in transporting the patient to higher care. They are very useful in performing [[CPR]], as the caregiver can deliver rescue breaths composed of 100% oxygen with the press of a button. Care must be taken not to over-inflate the patient's lungs, and some systems employ safety valves to help prevent this. These systems may not be appropriate for unconscious patients or those in respiratory distress, because of the effort required to breathe from them.


===High flow oxygen delivery===
===High flow oxygen delivery===


In cases where the patient requires a high concentration of up to 100% oxygen, a number of devices are available, with the most common being the [[non-rebreather mask]] (or reservoir mask), which is similar to the partial rebreathing mask except it has a series of one-way valves preventing exhaled air from returning to the bag. There should be a minimum flow of 10 L/min. The delivered FIO2 of this system is 60-80%, depending on the oxygen flow and breathing pattern.<ref>{{cite journal |author=Garcia JA, Gardner D, Vines D, Shelledy D, Wettstein R, Peters J |title=The Oxygen Concentrations Delivered by Different Oxygen Therapy Systems |journal=Chest Meeting |volume=128 |issue=4 |pages=389S–390S |date=October 2005 |url=http://meeting.chestpubs.org/cgi/content/abstract/128/4/389S-b?sid=1f94208b-0963-4d3e-9e2e-c6bd074b19c5 |doi=10.1378/chest.128.4_meetingabstracts.389s-b}}</ref><ref>[http://www.cardinal.com/mps/focus/respiratory/abstracts/abstracts/ab2003/OF-03-257.asp Earl, John. Delivery of High Fi{{chem|O|2}}. Cardinal Health Respiratory Abstracts.]</ref>
In cases where the patient requires a high concentration of up to 100% oxygen, a number of devices are available, with the most common being the [[non-rebreather mask]] (or reservoir mask), which is similar to the partial rebreathing mask except it has a series of one-way valves preventing exhaled air from returning to the bag. There should be a minimum flow of 10 L/min. The delivered FIO2 of this system is 60-80%, depending on the oxygen flow and breathing pattern.<ref>{{cite journal |author=Garcia JA, Gardner D, Vines D, Shelledy D, Wettstein R, Peters J |title=The Oxygen Concentrations Delivered by Different Oxygen Therapy Systems |journal=Chest Meeting |volume=128 |issue=4 |pages=389S–390S |date=October 2005 |url=http://meeting.chestpubs.org/cgi/content/abstract/128/4/389S-b?sid=1f94208b-0963-4d3e-9e2e-c6bd074b19c5 |doi=10.1378/chest.128.4_meetingabstracts.389s-b}}</ref><ref>[http://www.cardinal.com/mps/focus/respiratory/abstracts/abstracts/ab2003/OF-03-257.asp Earl, John. Delivery of High Fi{{chem|O|2}}. Cardinal Health Respiratory Abstracts.]</ref>
Another type of device is a humidified high flow [[nasal cannula]] which enables flows exceeding a patient's peak inspiratory flow demand to be delivered via nasal cannula, thus providing FiO2 of up to 100% because there is no entrainment of room air, even with the mouth open.<ref>[http://www.myoptiflow.com/therapy/ Accurate Oxygen Delivery]</ref> This also allows the patient to continue to talk, eat and drink while still receiving the therapy.<ref name="sim2008">{{cite journal |last1=Sim |first1=DA |last2=Dean |first2=P |last3=Kinsella |first3=J |last4=Black |first4=R |last5=Carter |first5=R |last6=Hughes |first6=M |date=September 2008 |title=Performance of oxygen delivery devices when the breathing pattern of respiratory failure is simulated. |journal=Anaesthesia |volume=63 |issue=9 |pages=938–40 |pmid=18540928 |doi=10.1111/j.1365-2044.2008.05536.x}}</ref> This type of delivery method is associated with greater overall comfort, and improved oxygenation and respiratory rates than with face mask oxygen.<ref>{{cite journal |author=Roca O, Riera J, Torres F, Masclans, JR. |title=High-flow oxygen therapy in acute respiratory failure. |journal=Respiratory Care |volume=55 |issue=4 |pages=408–13. |date=April 2010 |url=http://www.myoptiflow.com/benefits/outcomes/roca-2010/ |pmid=20406507 }}</ref>
Another type of device is a humidified high flow [[nasal cannula]] which enables flows exceeding a patient's peak inspiratory flow demand to be delivered via nasal cannula, thus providing FiO2 of up to 100% because there is no entrainment of room air, even with the mouth open.<ref>[http://www.myoptiflow.com/therapy/ Accurate Oxygen Delivery]</ref> This also allows the patient to continue to talk, eat and drink while still receiving the therapy.<ref name="sim2008">{{cite journal |last1=Sim |first1=DA |last2=Dean |first2=P |last3=Kinsella |first3=J |last4=Black |first4=R |last5=Carter |first5=R |last6=Hughes |first6=M |date=September 2008 |title=Performance of oxygen delivery devices when the breathing pattern of respiratory failure is simulated. |journal=Anaesthesia |volume=63 |issue=9 |pages=938–40 |pmid=18540928 |doi=10.1111/j.1365-2044.2008.05536.x}}</ref> This type of delivery method is associated with greater overall comfort, and improved oxygenation and respiratory rates than with face mask oxygen.<ref>{{cite journal |author=Roca O, Riera J, Torres F, Masclans, JR. |title=High-flow oxygen therapy in acute respiratory failure. |journal=Respiratory Care |volume=55 |issue=4 |pages=408–13. |date=April 2010 |url=http://www.myoptiflow.com/benefits/outcomes/roca-2010/ |pmid=20406507 }}</ref>


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===Positive pressure delivery===
===Positive pressure delivery===
Patients who are unable to breathe on their own will require positive pressure to move oxygen into their lungs for gaseous exchange to take place. Systems for delivering this vary in complexity (and cost), starting with a basic [[pocket mask]] adjunct which can be used by a basically trained first aider to manually deliver [[artificial respiration]] with supplemental oxygen delivered through a port in the mask.
Patients who are unable to breathe on their own will require positive pressure to move oxygen into their lungs for gaseous exchange to take place. Systems for delivering this vary in complexity (and cost), starting with a basic [[pocket mask]] adjunct which can be used by a basically trained first aider to manually deliver [[artificial respiration]] with supplemental oxygen delivered through a port in the mask.


Many [[emergency medical service]] and [[first aid]] personnel, as well as hospitals, will use a [[bag-valve-mask]] (BVM), which is a malleable bag attached to a face mask (or invasive airway such as an [[endotracheal tube]] or [[laryngeal mask airway]]), usually with a reservoir bag attached, which is manually manipulated by the healthcare professional to push oxygen (or air) into the lungs. This is the only procedure allowed for initial treatment of [[cyanide poisoning]] in the [[UK]] workplace.<ref>[http://www.hse.gov.uk/pubns/misc076.htm Cyanide poisoning — New recommendations on first aid treatment]</ref>
Many [[emergency medical service]] and [[first aid]] personnel, as well as hospitals, will use a [[bag-valve-mask]] (BVM), which is a malleable bag attached to a face mask (or invasive airway such as an [[endotracheal tube]] or [[laryngeal mask airway]]), usually with a reservoir bag attached, which is manually manipulated by the healthcare professional to push oxygen (or air) into the lungs. This is the only procedure allowed for initial treatment of [[cyanide poisoning]] in the [[UK]] workplace.<ref>[http://www.hse.gov.uk/pubns/misc076.htm Cyanide poisoning — New recommendations on first aid treatment]</ref>


Automated versions of the BVM system, known as a [[resuscitator]] or pneupac can also deliver measured and timed doses of oxygen direct to patient through a facemask or airway. These systems are related to the [[anaesthetic machine]]s used in operations under [[general anaesthesia]] that allows a variable amount of oxygen to be delivered, along with other gases including [[air]], [[nitrous oxide]] and [[inhalational anaesthetic]]s.
Automated versions of the BVM system, known as a [[resuscitator]] or pneupac can also deliver measured and timed doses of oxygen direct to patient through a facemask or airway. These systems are related to the [[anaesthetic machine]]s used in operations under [[general anaesthesia]] that allows a variable amount of oxygen to be delivered, along with other gases including air, [[nitrous oxide]] and [[inhalational anaesthetic]]s.


===As a drug delivery route===
===As a drug delivery route===
Oxygen and other compressed gasses are used in conjunction with a nebulizer for topical delivery of medications to the upper and lower airways. Nebulizers use compressed gas to propel liquid medication into an aerosol, with specific therapeutically sized droplets, for deposition in the appropriate, desired airway. Compressed gas, usually at flows of 8-10 L/min, is used to "nebulize" medications, saline and sterile water into a theraputeic aerosol for inhalation. In the clinical setting room air(ambient mix of several gasses), Oxygen and Heli-Ox gas are commonly used to nebulize small, large and continuous volumes of liquid.
Oxygen and other compressed gasses are used in conjunction with a nebulizer for topical delivery of medications to the upper and lower airways. Nebulizers use compressed gas to propel liquid medication into an aerosol, with specific therapeutically sized droplets, for deposition in the appropriate, desired airway. Compressed gas, usually at flows of 8-10 L/min, is used to "nebulize" medications, saline and sterile water into a theraputeic aerosol for inhalation. In the clinical setting room air (ambient mix of several gasses), Oxygen and Heli-Ox gas are commonly used to nebulize small, large and continuous volumes of liquid.


===Filtered oxygen masks===
===Filtered oxygen masks===
Filtered oxygen masks have the ability to prevent exhaled, potentially infectious particles from being released into the surrounding environment. These masks are normally of a closed design such that leaks are minimized and breathing of room air is controlled through a series of one-way valves. Filtration of exhaled breaths is accomplished either by placing a filter on the exhalation port, or through an integral filter that is part of the mask itself. These masks first became popular in the Toronto (Canada) healthcare community during the 2003 SARS Crisis. SARS was identified as being respiratory based and it was determined that conventional oxygen therapy devices were not designed for the containment of exhaled particles.<ref>{{cite journal |author=Hui DS, Hall SD, Chan MT, ''et al.'' |title=Exhaled air dispersion during oxygen delivery via a simple oxygen mask |journal=Chest |volume=132 |issue=2 |pages=540–6 |date=August 2007 |pmid=17573505 |doi=10.1378/chest.07-0636 |url=http://www.chestjournal.org/cgi/pmidlookup?view=long&pmid=17573505}}</ref><ref>{{cite journal |author=Mardimae A, Slessarev M, Han J, ''et al.'' |title=Modified N95 mask delivers high inspired oxygen concentrations while effectively filtering aerosolized microparticles |journal=Annals of Emergency Medicine |volume=48 |issue=4 |pages=391–9, 399.e1–2 |date=October 2006 |pmid=16997675 |doi=10.1016/j.annemergmed.2006.06.039 |url=http://linkinghub.elsevier.com/retrieve/pii/S0196-0644(06)00942-5}}</ref><ref>{{cite journal |author=Somogyi R, Vesely AE, Azami T, ''et al.'' |title=Dispersal of respiratory droplets with open vs closed oxygen delivery masks: implications for the transmission of severe acute respiratory syndrome |journal=Chest |volume=125 |issue=3 |pages=1155–7 |date=March 2004 |pmid=15006983 |url=http://www.chestjournal.org/cgi/pmidlookup?view=long&pmid=15006983 |doi=10.1378/chest.125.3.1155}}</ref> Common practices of having suspected patients wear a surgical mask was confounded by the use of standard oxygen therapy equipment. In 2003, the HiOx<sup>80</sup> oxygen mask was released for sale. The HiOx<sup>80</sup> mask is a closed design mask that allows a filter to be placed on the exhalation port. Several new designs have emerged in the global healthcare community for the containment and filtration of potentially infectious particles. Other designs include the ISO-{{chem|O|2}} oxygen mask, the Flo<sub>2</sub>Max oxygen mask, and the O-Mask. The use of oxygen masks that are capable of filtering exhaled particles is gradually becoming a recommended practice for pandemic preparation in many jurisdictions.
Filtered oxygen masks have the ability to prevent exhaled, potentially infectious particles from being released into the surrounding environment. These masks are normally of a closed design such that leaks are minimized and breathing of room air is controlled through a series of one-way valves. Filtration of exhaled breaths is accomplished either by placing a filter on the exhalation port, or through an integral filter that is part of the mask itself. These masks first became popular in the Toronto (Canada) healthcare community during the 2003 SARS Crisis. SARS was identified as being respiratory based and it was determined that conventional oxygen therapy devices were not designed for the containment of exhaled particles.<ref>{{cite journal |author=Hui DS, Hall SD, Chan MT, ''et al.'' |title=Exhaled air dispersion during oxygen delivery via a simple oxygen mask |journal=Chest |volume=132 |issue=2 |pages=540–6 |date=August 2007 |pmid=17573505 |doi=10.1378/chest.07-0636 |url=http://www.chestjournal.org/cgi/pmidlookup?view=long&pmid=17573505}}</ref><ref>{{cite journal |author=Mardimae A, Slessarev M, Han J, ''et al.'' |title=Modified N95 mask delivers high inspired oxygen concentrations while effectively filtering aerosolized microparticles |journal=Annals of Emergency Medicine |volume=48 |issue=4 |pages=391–9, 399.e1–2 |date=October 2006 |pmid=16997675 |doi=10.1016/j.annemergmed.2006.06.039 |url=http://linkinghub.elsevier.com/retrieve/pii/S0196-0644(06)00942-5}}</ref><ref>{{cite journal |author=Somogyi R, Vesely AE, Azami T, ''et al.'' |title=Dispersal of respiratory droplets with open vs closed oxygen delivery masks: implications for the transmission of severe acute respiratory syndrome |journal=Chest |volume=125 |issue=3 |pages=1155–7 |date=March 2004 |pmid=15006983 |url=http://www.chestjournal.org/cgi/pmidlookup?view=long&pmid=15006983 |doi=10.1378/chest.125.3.1155}}</ref> Common practices of having suspected patients wear a surgical mask was confounded by the use of standard oxygen therapy equipment. In 2003, the HiOx<sup>80</sup> oxygen mask was released for sale. The HiOx<sup>80</sup> mask is a closed design mask that allows a filter to be placed on the exhalation port. Several new designs have emerged in the global healthcare community for the containment and filtration of potentially infectious particles. Other designs include the ISO-{{chem|O|2}} oxygen mask, the Flo<sub>2</sub>Max oxygen mask, and the O-Mask. The use of oxygen masks that are capable of filtering exhaled particles is gradually becoming a recommended practice for pandemic preparation in many jurisdictions.


Because filtered oxygen masks use a closed design that minimizes or eliminates inadvertent exposure to room air, delivered oxygen concentrations to the patient have been found to be higher than conventional non-rebreather masks, approaching 99% using adequate oxygen flows. Because all exhaled particles are contained within the mask, nebulized medications <!-- link to the wiki page nebulizer --> are also prevented from being released into the surrounding atmosphere, decreasing the occupational exposure to healthcare staff and other patients.
Because filtered oxygen masks use a closed design that minimizes or eliminates inadvertent exposure to room air, delivered oxygen concentrations to the patient have been found to be higher than conventional non-rebreather masks, approaching 99% using adequate oxygen flows. Because all exhaled particles are contained within the mask, nebulized medications <!-- link to the wiki page nebulizer --> are also prevented from being released into the surrounding atmosphere, decreasing the occupational exposure to healthcare staff and other patients.


==Negative effects==
==Negative effects==
Many [[Emergency medical services|EMS]] protocols indicate that oxygen should not be withheld from any patient, while other protocols are more specific or circumspect. However, there are certain situations in which oxygen therapy is known to have a negative impact on a patient’s condition.<ref name="Patarinski1976">{{cite journal|last=Patarinski|first=D|year=1976|title=Indications and contraindications for oxygen therapy of respiratory insufficiency|journal=Vŭtreshni bolesti|volume=15|issue=4|pages=44–50|pmid=1007238|language=Bulgarian with English abstract}}</ref>
Many [[Emergency medical services|EMS]] protocols indicate that oxygen should not be withheld from any patient, while other protocols are more specific or circumspect. However, there are certain situations in which oxygen therapy is known to have a negative impact on a patient’s condition.<ref name="Patarinski1976">{{cite journal|last=Patarinski|first=D|year=1976|title=Indications and contraindications for oxygen therapy of respiratory insufficiency|journal=Vŭtreshni bolesti|volume=15|issue=4|pages=44–50|pmid=1007238|language=Bulgarian with English abstract}}</ref>


Oxygen should never be given to a patient who is suffering from [[paraquat#Health_risks|paraquat poisoning]] unless they are suffering from severe respiratory distress or respiratory arrest, as this can increase the toxicity. (Paraquat poisoning is rare — for example 200 deaths globally from 1958 to 1978).<ref>[http://www.sma.org.sg/smj/4712/4712a2.pdf Experience with paraquat poisoning in a respiratory intensive care unit in North India]</ref> Oxygen therapy is not recommended for patients who have suffered [[pulmonary fibrosis]] or other lung damage resulting from [[bleomycin]] treatment.<ref name="phecc2009">{{cite web |url=http://www.phecit.ie/Documents/Clinical%20Practice%20Guidelines/EMT%203rd%20Edition%20CPGs/EMT%20Appendix%201%20Medication%20Formulary.pdf |title=EMT Medication Formulary |date=15 July 2009 |work=PHECC Clinical Practice Guidelines |publisher=[[Pre-Hospital Emergency Care Council]] |page=84 |accessdate=14 April 2010}}</ref>
Oxygen should never be given to a patient who is suffering from [[paraquat#Health risks|paraquat poisoning]] unless they are suffering from severe respiratory distress or respiratory arrest, as this can increase the toxicity. (Paraquat poisoning is rare — for example 200 deaths globally from 1958 to 1978).<ref>[http://www.sma.org.sg/smj/4712/4712a2.pdf Experience with paraquat poisoning in a respiratory intensive care unit in North India]</ref> Oxygen therapy is not recommended for patients who have suffered [[pulmonary fibrosis]] or other lung damage resulting from [[bleomycin]] treatment.<ref name="phecc2009">{{cite web |url=http://www.phecit.ie/Documents/Clinical%20Practice%20Guidelines/EMT%203rd%20Edition%20CPGs/EMT%20Appendix%201%20Medication%20Formulary.pdf |title=EMT Medication Formulary |date=15 July 2009 |work=PHECC Clinical Practice Guidelines |publisher=[[Pre-Hospital Emergency Care Council]] |page=84 |accessdate=2010-04-14}}</ref>


High levels of oxygen given to infants causes [[blindness]] by promoting overgrowth of new blood vessels in the eye obstructing sight. This is [[retinopathy of prematurity]] (ROP).
High levels of oxygen given to infants causes blindness by promoting overgrowth of new blood vessels in the eye obstructing sight. This is [[retinopathy of prematurity]] (ROP).


Oxygen has [[Vasoconstriction|vasoconstrictive]] effects on the circulatory system, reducing peripheral circulation and was once thought to potentially increase the effects of [[stroke]]. However, when additional oxygen is given to the patient, additional oxygen is dissolved in the plasma according to [[Henry's Law]]. This allows a compensating change to occur and the dissolved oxygen in plasma supports embarrassed (oxygen-starved) neurons, reduces inflammation and post-stroke cerebral edema. Since 1990, hyperbaric oxygen therapy has been used in the treatments of stroke on a worldwide basis. In rare instances, hyperbaric oxygen therapy patients have had seizures. However, because of the aforementioned Henry's Law effect of extra available dissolved oxygen to neurons, there is usually no negative sequel to the event. Such seizures are generally a result of [[oxygen toxicity]],<ref name=smerz>{{cite journal |author=Smerz, R.W. |title=Incidence of oxygen toxicity during the treatment of dysbarism |journal=Undersea and Hyperbaric Medicine |volume=31 |issue=2 |pages=199–202 |year=2004 |pmid=15485081 |url=http://archive.rubicon-foundation.org/4010 |accessdate=2008-04-30 }}</ref><ref>{{cite journal |author=Hampson, Neal B.; Simonson, Steven G.; Kramer, C.C.; Piantadosi, Claude A. |title=Central nervous system oxygen toxicity during hyperbaric treatment of patients with carbon monoxide poisoning |journal=Undersea and Hyperbaric Medicine |volume=23 |issue=4 |pages=215–9 |year=1996 |pmid=8989851 |url=http://archive.rubicon-foundation.org/2232 |accessdate=2008-04-29 }}</ref> although [[hypoglycemia]] may be a contributing factor, but the latter risk can be eradicated or reduced by carefully monitoring the patient's nutritional intake prior to oxygen treatment.
Oxygen has [[Vasoconstriction|vasoconstrictive]] effects on the circulatory system, reducing peripheral circulation and was once thought to potentially increase the effects of [[stroke]]. However, when additional oxygen is given to the patient, additional oxygen is dissolved in the plasma according to [[Henry's Law]]. This allows a compensating change to occur and the dissolved oxygen in plasma supports embarrassed (oxygen-starved) neurons, reduces inflammation and post-stroke cerebral edema. Since 1990, hyperbaric oxygen therapy has been used in the treatments of stroke on a worldwide basis. In rare instances, hyperbaric oxygen therapy patients have had seizures. However, because of the aforementioned Henry's Law effect of extra available dissolved oxygen to neurons, there is usually no negative sequel to the event. Such seizures are generally a result of [[oxygen toxicity]],<ref name=smerz>{{cite journal |author=Smerz, R.W. |title=Incidence of oxygen toxicity during the treatment of dysbarism |journal=Undersea and Hyperbaric Medicine |volume=31 |issue=2 |pages=199–202 |year=2004 |pmid=15485081 |url=http://archive.rubicon-foundation.org/4010 |accessdate=2008-04-30}}</ref><ref>{{cite journal |author=Hampson, Neal B.; Simonson, Steven G.; Kramer, C.C.; Piantadosi, Claude A. |title=Central nervous system oxygen toxicity during hyperbaric treatment of patients with carbon monoxide poisoning |journal=Undersea and Hyperbaric Medicine |volume=23 |issue=4 |pages=215–9 |year=1996 |pmid=8989851 |url=http://archive.rubicon-foundation.org/2232 |accessdate=2008-04-29}}</ref> although [[hypoglycemia]] may be a contributing factor, but the latter risk can be eradicated or reduced by carefully monitoring the patient's nutritional intake prior to oxygen treatment.


Oxygen first aid has been used as an emergency treatment for [[Scuba diving|diving]] injuries for years.<ref name=Brubakk>{{cite book |title=Bennett and Elliott's physiology and medicine of diving, 5th Rev ed. |last=Brubakk |first=A. O. |coauthors=T. S. Neuman |year=2003 |publisher=Saunders Ltd. |location=United States |isbn=0-7020-2571-2 |page=800 }}</ref> Recompression in a [[hyperbaric chamber]] with the patient breathing 100% oxygen is the standard hospital and military medical response to [[decompression illness]].<ref name=Brubakk/><ref>{{cite web |url=http://www.uhms.org/ResourceLibrary/Indications/DecompressionSickness/tabid/275/Default.aspx |title=Decompression Sickness or Illness and Arterial Gas Embolism |author=Undersea and Hyperbaric Medical Society |accessdate=2008-05-30 }}</ref><ref>{{cite journal |last=Acott |first=C. |title=A brief history of diving and decompression illness |journal=South Pacific Underwater Medicine Society Journal |volume=29 |issue=2 |year=1999 |issn=0813-1988 |oclc=16986801 |url=http://archive.rubicon-foundation.org/6004 |accessdate=2008-05-30 }}</ref> The success of recompression therapy as well as a decrease in the number of recompression treatments required has been shown if first aid oxygen is given within four hours after surfacing.<ref name=Longphre>{{cite journal |last=Longphre |first=J. M. |coauthors=P. J. DeNoble; R. E. Moon; R. D. Vann; J. J. Freiberger |title=First aid normobaric oxygen for the treatment of recreational diving injuries |journal=Undersea Hyperb Med. |volume=34 |issue=1 |pages=43–49 |year=2007 |issn=1066-2936 |oclc=26915585 |pmid=17393938 |url=http://archive.rubicon-foundation.org/5514 |accessdate=2008-05-30 }}</ref> There are suggestions that oxygen administration may not be the most effective measure for the treatment of decompression illness and that [[heliox]] may be a better alternative.<ref>{{cite journal |author=Kol S, Adir Y, Gordon CR, Melamed Y |title=Oxy-helium treatment of severe spinal decompression sickness after air diving |journal=Undersea Hyperb Med |volume=20 |issue=2 |pages=147–54 |date=June 1993 |pmid=8329941 |url=http://archive.rubicon-foundation.org/2133 |accessdate=2008-05-30}}</ref>
Oxygen first aid has been used as an emergency treatment for [[Scuba diving|diving]] injuries for years.<ref name=Brubakk>{{cite book |title=Bennett and Elliott's physiology and medicine of diving, 5th Rev ed. |last=Brubakk |first=A. O. |coauthors=T. S. Neuman |year=2003 |publisher=Saunders Ltd. |location=United States |isbn=0-7020-2571-2 |page=800 }}</ref> Recompression in a [[hyperbaric chamber]] with the patient breathing 100% oxygen is the standard hospital and military medical response to [[decompression illness]].<ref name=Brubakk/><ref>{{cite web |url=http://www.uhms.org/ResourceLibrary/Indications/DecompressionSickness/tabid/275/Default.aspx |title=Decompression Sickness or Illness and Arterial Gas Embolism |author=Undersea and Hyperbaric Medical Society |accessdate=2008-05-30}}</ref><ref>{{cite journal |last=Acott |first=C. |title=A brief history of diving and decompression illness |journal=South Pacific Underwater Medicine Society Journal |volume=29 |issue=2 |year=1999 |issn=0813-1988 |oclc=16986801 |url=http://archive.rubicon-foundation.org/6004 |accessdate=2008-05-30}}</ref> The success of recompression therapy as well as a decrease in the number of recompression treatments required has been shown if first aid oxygen is given within four hours after surfacing.<ref name=Longphre>{{cite journal |last=Longphre |first=J. M. |coauthors=P. J. DeNoble; R. E. Moon; R. D. Vann; J. J. Freiberger |title=First aid normobaric oxygen for the treatment of recreational diving injuries |journal=Undersea Hyperb Med. |volume=34 |issue=1 |pages=43–49 |year=2007 |issn=1066-2936 |oclc=26915585 |pmid=17393938 |url=http://archive.rubicon-foundation.org/5514 |accessdate=2008-05-30}}</ref> There are suggestions that oxygen administration may not be the most effective measure for the treatment of decompression illness and that [[heliox]] may be a better alternative.<ref>{{cite journal |author=Kol S, Adir Y, Gordon CR, Melamed Y |title=Oxy-helium treatment of severe spinal decompression sickness after air diving |journal=Undersea Hyperb Med |volume=20 |issue=2 |pages=147–54 |date=June 1993 |pmid=8329941 |url=http://archive.rubicon-foundation.org/2133 |accessdate=2008-05-30}}</ref>


=== Chronic obstructive pulmonary disease ===
=== Chronic obstructive pulmonary disease ===
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===Fire risk===
===Fire risk===
Highly concentrated sources of oxygen promote rapid combustion. Oxygen itself is not flammable, but the addition of concentrated oxygen to a fire greatly increases its intensity, and can aid the combustion of materials (such as metals) which are relatively inert under normal conditions. [[Fire]] and [[explosion]] hazards exist when concentrated oxidants and [[fuel]]s are brought into close proximity; however, an ignition event, such as heat or a spark, is needed to trigger combustion.<ref name="astm-tpt">{{cite conference|last=Werley|first=Barry L. (Edtr.)|year=1991|title=Fire Hazards in Oxygen Systems|booktitle=ASTM Technical Professional training|publisher=[[ASTM International]] Subcommittee G-4.05|location=Philadelphia}}</ref> A well-known example of an accidental fire accelerated by pure oxygen under pressure occurred in the [[Apollo 1]] spacecraft in January 1967 during a ground test; it killed all three astronauts. A similar accident killed Soviet cosmonaut [[Valentin Bondarenko]] in 1961.
Highly concentrated sources of oxygen promote rapid combustion. Oxygen itself is not flammable, but the addition of concentrated oxygen to a fire greatly increases its intensity, and can aid the combustion of materials (such as metals) which are relatively inert under normal conditions. Fire and [[explosion]] hazards exist when concentrated oxidants and [[fuel]]s are brought into close proximity; however, an ignition event, such as heat or a spark, is needed to trigger combustion.<ref name="astm-tpt">{{cite conference|last=Werley|first=Barry L. (Edtr.)|year=1991|title=Fire Hazards in Oxygen Systems|booktitle=ASTM Technical Professional training|publisher=[[ASTM International]] Subcommittee G-4.05|location=Philadelphia}}</ref> A well-known example of an accidental fire accelerated by pure oxygen under pressure occurred in the [[Apollo 1]] spacecraft in January 1967 during a ground test; it killed all three astronauts. A similar accident killed Soviet cosmonaut [[Valentin Bondarenko]] in 1961.


Combustion hazards also apply to compounds of oxygen with a high oxidative potential, such as [[peroxide]]s, [[chlorate]]s, [[nitrate]]s, [[perchlorate]]s, and [[dichromate]]s because they can donate oxygen to a fire.
Combustion hazards also apply to compounds of oxygen with a high oxidative potential, such as [[peroxide]]s, [[chlorate]]s, [[nitrate]]s, [[perchlorate]]s, and [[dichromate]]s because they can donate oxygen to a fire.


Concentrated {{chem|O|2}} will allow combustion to proceed rapidly and energetically.<ref name="astm-tpt" /> [[Steel]] pipes and storage vessels used to store and transmit both gaseous and [[liquid oxygen]] will act as a fuel; and therefore the design and manufacture of {{chem|O|2}} systems requires special training to ensure that ignition sources are minimized.<ref name="astm-tpt" /> Highly concentrated oxygen in a high-pressure environment can spontaneously ignite hydrocarbons such as oil and grease, resulting in fire or explosion. The heat caused by rapid pressurization serves as the ignition source. For this reason, storage vessels, regulators, piping and any other equipment used with highly concentrated oxygen must be "oxygen-clean" prior to use, to ensure the absence of potential fuels. This does not apply only to pure oxygen; any concentration significantly higher than atmospheric (approximately 21%) carries a potential risk.
Concentrated {{chem|O|2}} will allow combustion to proceed rapidly and energetically.<ref name="astm-tpt" /> Steel pipes and storage vessels used to store and transmit both gaseous and [[liquid oxygen]] will act as a fuel; and therefore the design and manufacture of {{chem|O|2}} systems requires special training to ensure that ignition sources are minimized.<ref name="astm-tpt" /> Highly concentrated oxygen in a high-pressure environment can spontaneously ignite hydrocarbons such as oil and grease, resulting in fire or explosion. The heat caused by rapid pressurization serves as the ignition source. For this reason, storage vessels, regulators, piping and any other equipment used with highly concentrated oxygen must be "oxygen-clean" prior to use, to ensure the absence of potential fuels. This does not apply only to pure oxygen; any concentration significantly higher than atmospheric (approximately 21%) carries a potential risk.


Hospitals in some jurisdictions, such as the UK, now operate “no-smoking” policies, which although introduced for other reasons, supports the aim of keeping ignition sources away from medical piped oxygen. Other recorded sources of ignition of medically prescribed oxygen include candles, aromatherapy, medical equipment, cooking, and unfortunately, deliberate vandalism. Smoking pipes, cigars and cigarettes are of special concern. This does not entirely eliminate the risk of injury with portable oxygen systems, especially if [[Compliance (medicine)|compliance]] is poor.<ref>{{cite journal|url=http://www.medbc.com/annals/review/vol_19/num_2/text/vol19n2p99.asp|title=Home Oxygen Therapy and Cigarette Smoking: A Dangerous Practice |author=Lindford AJ, Tehrani H, Sassoon EM, O'Neill TJ |journal=Annals of Burns and Fire Disasters|volume=19|issue=2|date=June 2006}}</ref>
Hospitals in some jurisdictions, such as the UK, now operate “no-smoking” policies, which although introduced for other reasons, supports the aim of keeping ignition sources away from medical piped oxygen. Other recorded sources of ignition of medically prescribed oxygen include candles, aromatherapy, medical equipment, cooking, and unfortunately, deliberate vandalism. Smoking pipes, cigars and cigarettes are of special concern. This does not entirely eliminate the risk of injury with portable oxygen systems, especially if [[Compliance (medicine)|compliance]] is poor.<ref>{{cite journal|url=http://www.medbc.com/annals/review/vol_19/num_2/text/vol19n2p99.asp|title=Home Oxygen Therapy and Cigarette Smoking: A Dangerous Practice |author=Lindford AJ, Tehrani H, Sassoon EM, O'Neill TJ |journal=Annals of Burns and Fire Disasters|volume=19|issue=2|date=June 2006}}</ref>


===In alternative medicine===
===In alternative medicine===
{{seealso|List of ineffective cancer treatments}}
{{see also|List of ineffective cancer treatments}}
Some practitioners of [[alternative medicine]] have promoted "oxygen therapy" as a cure for many human ailments including [[AIDS]], [[Alzheimer's disease]] and [[cancer]]. The procedure may include injecting hydrogen peroxide, oxygenating blood, or administering oxygen under pressure to the rectum, vagina, or other bodily opening. According to the [[American Cancer Society]], "available scientific evidence does not support claims that putting oxygen-releasing chemicals into a person's body is effective in treating cancer", and some of these treatments can be dangerous.<ref>{{cite web
Some practitioners of [[alternative medicine]] have promoted "oxygen therapy" as a cure for many human ailments including [[AIDS]], [[Alzheimer's disease]] and [[cancer]]. The procedure may include injecting hydrogen peroxide, oxygenating blood, or administering oxygen under pressure to the rectum, vagina, or other bodily opening. According to the [[American Cancer Society]], "available scientific evidence does not support claims that putting oxygen-releasing chemicals into a person's body is effective in treating cancer", and some of these treatments can be dangerous.<ref>{{cite web
|url=http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/pharmacologicalandbiologicaltreatment/oxygen-therapy
|url=http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/pharmacologicalandbiologicaltreatment/oxygen-therapy
Line 152: Line 152:
|date=26 December 2012
|date=26 December 2012
|publisher=[[American Cancer Society]]
|publisher=[[American Cancer Society]]
|accessdate=20 September 2013}}</ref>
|accessdate=2013-09-20}}</ref>


== Oxygen therapy while on aircraft ==
== Oxygen therapy while on aircraft ==
In the [[United States]], most [[airlines]] restrict the devices allowed on board [[aircraft]]. As a result passengers are restricted in what devices they can use. Some airlines will provide cylinders for passengers with an associated fee. Other airlines allow passengers to carry on approved portable concentrators. However the lists of approved devices varies by airline so passengers need to check with any airline they are planning to fly on. Passengers are generally not allowed to carry on their own cylinders. In all cases, passengers need to notify the airline in advance of their equipment.
In the [[United States]], most airlines restrict the devices allowed on board aircraft. As a result passengers are restricted in what devices they can use. Some airlines will provide cylinders for passengers with an associated fee. Other airlines allow passengers to carry on approved portable concentrators. However the lists of approved devices varies by airline so passengers need to check with any airline they are planning to fly on. Passengers are generally not allowed to carry on their own cylinders. In all cases, passengers need to notify the airline in advance of their equipment.


Effective May 13, 2009, the Department of Transportation and FAA ruled that a select number of portable oxygen concentrators are approved for use on all commercial flights.<ref>http://www.faa.gov/about/initiatives/cabin_safety/portable_oxygen/</ref> The list of approved portable oxygen concentrators includes the Respironics EverGo, the Invacare XPO2, the Invacare Solo 2 and others.<ref>http://www.open-aire.com/rentalcenter/</ref>
Effective May 13, 2009, the Department of Transportation and FAA ruled that a select number of portable oxygen concentrators are approved for use on all commercial flights.<ref name="faa">{{cite web|url=http://www.faa.gov/about/initiatives/cabin_safety/portable_oxygen/|title=FAA Approved Portable Oxygen Concentrators - Positive Testing Results|publisher=faa.gov|accessdate=2014-06-22}}</ref> The list of approved portable oxygen concentrators includes the Respironics EverGo, the Invacare XPO2, the Invacare Solo 2 and others.<ref>http://www.open-aire.com/rentalcenter/</ref>


FAA regulations require larger airplanes to carry D-cylinders of oxygen for use in an emergency.
FAA regulations require larger airplanes to carry D-cylinders of oxygen for use in an emergency.

Revision as of 08:14, 22 June 2014

Oxygen therapy
A patient wearing a simple face mask
ICD-9-CM93.96
MeSHD010102
Oxygen piping and regulator with flow meter, for oxygen therapy, mounted in an ambulance
Oxygen Regulator for portable D-Cylinder, usually carried in an ambulance's resuscitation kit.

Oxygen therapy is the administration of oxygen as a medical intervention, which can be for a variety of purposes in both chronic and acute patient care. Oxygen is essential for cell metabolism, and in turn, tissue oxygenation is essential for all normal physiological functions.[1]

High blood and tissue levels of oxygen can be helpful or damaging, depending on circumstances and oxygen therapy should be used to benefit the patient by increasing the supply of oxygen to the lungs and thereby increasing the availability of oxygen to the body tissues, especially when the patient is suffering from hypoxia and/or hypoxaemia.

Indications for use

Oxygen is used as a medical treatment in both chronic and acute cases, and can be used in hospital, pre-hospital or entirely out of hospital, dependent on the needs of the patient and their medical professionals' opinions.

Use in chronic conditions

A common use of supplementary oxygen is in patients with chronic obstructive pulmonary disease (COPD), the occurrence of chronic bronchitis or emphysema, a common long term effect of smoking, who may require additional oxygen to breathe either during a temporary worsening of their condition, or throughout the day and night. It is indicated in COPD patients with PaO
2
≤ 55mmHg or SaO
2
≤ 88% and has been shown to increase lifespan.[2][3][4]

Oxygen is often prescribed for people with breathlessness, in the setting of end-stage cardiac or respiratory failure, advanced cancer or neurodegenerative disease, despite having relatively normal blood oxygen levels. A 2010 trial of 239 subjects found no significant difference in reducing breathlessness between oxygen and air delivered in the same way.[5]

Use in acute conditions

Oxygen is widely used in emergency medicine, both in hospital and by emergency medical services or those giving advanced first aid.

In the pre-hospital environment, high flow oxygen is definitively indicated for use in resuscitation, major trauma, anaphylaxis, major haemorrhage, shock, active convulsions and hypothermia.[1][6]

It may also be indicated for any other patient where their injury or illness has caused hypoxaemia, although in this case oxygen flow should be moderated to achieve target oxygen saturation levels, based on pulse oximetry (with a target level of 94–98% in most patients, or 88–92% in COPD patients).[1]

For personal use, high concentration oxygen is used as home therapy to abort cluster headache attacks, due to its vaso-constrictive effects.[7]

Patients who are receiving oxygen therapy for hypoxemia following an acute illness or hospitalization should not routinely have a prescription renewal for continued oxygen therapy without a physician's re-assessment of the patient's condition.[8] If the patient has recovered from the illness, then the hypoxemia is expected to resolve and additional care would be unnecessary and a waste of resources.[8]

Storage and sources

Gas cylinders containing oxygen to be used at home. When in use a pipe is attached to the cylinder's regulator and then to a mask that fits over the patient's nose and mouth.
A home oxygen concentrator in situ in an emphysema patient's house.

Oxygen can be separated by a number of methods, including chemical reaction and fractional distillation, and then either used immediately or stored for future use. The main types sources for oxygen therapy are:

  1. Liquid storage — Liquid oxygen is stored in chilled tanks until required, and then allowed to boil (at a temperature of 90.188 K (−182.96 °C)) to release oxygen as a gas. This is widely used at hospitals due to their high usage requirements, but can also be used in other settings. See Vacuum Insulated Evaporator for more information on this method of storage.
  2. Compressed gas storage — The oxygen gas is compressed in a gas cylinder, which provides a convenient storage, without the requirement for refrigeration found with liquid storage. Large oxygen cylinders hold 6,500 litres (230 cu ft) and can last about two days at a flow rate of 2 litres per minute. A small portable M6 (B) cylinder holds 164 or 170 litres (5.8 or 6.0 cu ft) and weighs about 1.3 to 1.6 kilograms (2.9 to 3.5 lb).[9] These tanks can last 4–6 hours when used with a conserving regulator, which senses the patient's breathing rate and sends pulses of oxygen. Conserving regulators may not be usable by patients who breathe through their mouths.
  3. Instant usage — The use of an electrically powered oxygen concentrator[10] or a chemical reaction based unit[11] can create sufficient oxygen for a patient to use immediately, and these units (especially the electrically powered versions) are in widespread usage for home oxygen therapy and portable personal oxygen, with the advantage of being continuous supply without the need for additional deliveries of bulky cylinders.

Delivery

Various devices are used for administration of oxygen. In most cases, the oxygen will first pass through a pressure regulator, used to control the high pressure of oxygen delivered from a cylinder (or other source) to a lower pressure. This lower pressure is then controlled by a flowmeter, which may be preset or selectable, and this controls the flow in a measure such as litres per minute (lpm). The typical flowmeter range for medical oxygen is between 0 and 15 lpm with some units able to obtain up to 25 liters per minute. Many wall flowmeters using a Thorpe tube design are able to be dialed to "flush" which is beneficial in emergency situations.

Supplemental oxygen

Many patients require only a supplementary level of oxygen in the room air they are breathing, rather than pure or near pure oxygen,[12] and this can be delivered through a number of devices dependent on the situation, flow required and in some instances patient preference.

A nasal cannula (NC) is a thin tube with two small nozzles that protrude into the patient's nostrils. It can only comfortably provide oxygen at low flow rates, 2–6 litres per minute (LPM), delivering a concentration of 24–40%.

There are also a number of face mask options, such as the simple face mask, often used at between 5 and 8 LPM, with a concentration of oxygen to the patient of between 28% and 50%. This is closely related to the more controlled air-entrainment masks, also known as Venturi masks, which can accurately deliver a predetermined oxygen concentration to the trachea up to 40%.

In some instances, a partial rebreathing mask can be used, which is based on a simple mask, but featuring a reservoir bag, which increases the provided oxygen concentration to 40–70% oxygen at 5 to 15 LPM.

Non-rebreather masks draw oxygen from an attached reservoir bags, with one-way valves that direct exhaled air out of the mask. When properly fitted and used at flow rates of 8-10 LPM or higher, they deliver close to 100% oxygen. This type of mask is indicated for acute medical emergencies.

Demand valves or oxygen resuscitators deliver oxygen only when the patient inhales, or, in the case of an apnic (non-breathing) victim, the caregiver presses a button on the mask. These systems greatly conserve oxygen compared to steady-flow masks, which is useful in emergency situations when a limited supply of oxygen is available and there is a delay in transporting the patient to higher care. They are very useful in performing CPR, as the caregiver can deliver rescue breaths composed of 100% oxygen with the press of a button. Care must be taken not to over-inflate the patient's lungs, and some systems employ safety valves to help prevent this. These systems may not be appropriate for unconscious patients or those in respiratory distress, because of the effort required to breathe from them.

High flow oxygen delivery

In cases where the patient requires a high concentration of up to 100% oxygen, a number of devices are available, with the most common being the non-rebreather mask (or reservoir mask), which is similar to the partial rebreathing mask except it has a series of one-way valves preventing exhaled air from returning to the bag. There should be a minimum flow of 10 L/min. The delivered FIO2 of this system is 60-80%, depending on the oxygen flow and breathing pattern.[13][14] Another type of device is a humidified high flow nasal cannula which enables flows exceeding a patient's peak inspiratory flow demand to be delivered via nasal cannula, thus providing FiO2 of up to 100% because there is no entrainment of room air, even with the mouth open.[15] This also allows the patient to continue to talk, eat and drink while still receiving the therapy.[16] This type of delivery method is associated with greater overall comfort, and improved oxygenation and respiratory rates than with face mask oxygen.[17]

In specialist applications such as aviation, tight fitting masks can be used, and these also have applications in anaesthesia, carbon monoxide poisoning treatment and in hyperbaric oxygen therapy

Positive pressure delivery

Patients who are unable to breathe on their own will require positive pressure to move oxygen into their lungs for gaseous exchange to take place. Systems for delivering this vary in complexity (and cost), starting with a basic pocket mask adjunct which can be used by a basically trained first aider to manually deliver artificial respiration with supplemental oxygen delivered through a port in the mask.

Many emergency medical service and first aid personnel, as well as hospitals, will use a bag-valve-mask (BVM), which is a malleable bag attached to a face mask (or invasive airway such as an endotracheal tube or laryngeal mask airway), usually with a reservoir bag attached, which is manually manipulated by the healthcare professional to push oxygen (or air) into the lungs. This is the only procedure allowed for initial treatment of cyanide poisoning in the UK workplace.[18]

Automated versions of the BVM system, known as a resuscitator or pneupac can also deliver measured and timed doses of oxygen direct to patient through a facemask or airway. These systems are related to the anaesthetic machines used in operations under general anaesthesia that allows a variable amount of oxygen to be delivered, along with other gases including air, nitrous oxide and inhalational anaesthetics.

As a drug delivery route

Oxygen and other compressed gasses are used in conjunction with a nebulizer for topical delivery of medications to the upper and lower airways. Nebulizers use compressed gas to propel liquid medication into an aerosol, with specific therapeutically sized droplets, for deposition in the appropriate, desired airway. Compressed gas, usually at flows of 8-10 L/min, is used to "nebulize" medications, saline and sterile water into a theraputeic aerosol for inhalation. In the clinical setting room air (ambient mix of several gasses), Oxygen and Heli-Ox gas are commonly used to nebulize small, large and continuous volumes of liquid.

Filtered oxygen masks

Filtered oxygen masks have the ability to prevent exhaled, potentially infectious particles from being released into the surrounding environment. These masks are normally of a closed design such that leaks are minimized and breathing of room air is controlled through a series of one-way valves. Filtration of exhaled breaths is accomplished either by placing a filter on the exhalation port, or through an integral filter that is part of the mask itself. These masks first became popular in the Toronto (Canada) healthcare community during the 2003 SARS Crisis. SARS was identified as being respiratory based and it was determined that conventional oxygen therapy devices were not designed for the containment of exhaled particles.[19][20][21] Common practices of having suspected patients wear a surgical mask was confounded by the use of standard oxygen therapy equipment. In 2003, the HiOx80 oxygen mask was released for sale. The HiOx80 mask is a closed design mask that allows a filter to be placed on the exhalation port. Several new designs have emerged in the global healthcare community for the containment and filtration of potentially infectious particles. Other designs include the ISO-O
2
oxygen mask, the Flo2Max oxygen mask, and the O-Mask. The use of oxygen masks that are capable of filtering exhaled particles is gradually becoming a recommended practice for pandemic preparation in many jurisdictions.

Because filtered oxygen masks use a closed design that minimizes or eliminates inadvertent exposure to room air, delivered oxygen concentrations to the patient have been found to be higher than conventional non-rebreather masks, approaching 99% using adequate oxygen flows. Because all exhaled particles are contained within the mask, nebulized medications are also prevented from being released into the surrounding atmosphere, decreasing the occupational exposure to healthcare staff and other patients.

Negative effects

Many EMS protocols indicate that oxygen should not be withheld from any patient, while other protocols are more specific or circumspect. However, there are certain situations in which oxygen therapy is known to have a negative impact on a patient’s condition.[22]

Oxygen should never be given to a patient who is suffering from paraquat poisoning unless they are suffering from severe respiratory distress or respiratory arrest, as this can increase the toxicity. (Paraquat poisoning is rare — for example 200 deaths globally from 1958 to 1978).[23] Oxygen therapy is not recommended for patients who have suffered pulmonary fibrosis or other lung damage resulting from bleomycin treatment.[24]

High levels of oxygen given to infants causes blindness by promoting overgrowth of new blood vessels in the eye obstructing sight. This is retinopathy of prematurity (ROP).

Oxygen has vasoconstrictive effects on the circulatory system, reducing peripheral circulation and was once thought to potentially increase the effects of stroke. However, when additional oxygen is given to the patient, additional oxygen is dissolved in the plasma according to Henry's Law. This allows a compensating change to occur and the dissolved oxygen in plasma supports embarrassed (oxygen-starved) neurons, reduces inflammation and post-stroke cerebral edema. Since 1990, hyperbaric oxygen therapy has been used in the treatments of stroke on a worldwide basis. In rare instances, hyperbaric oxygen therapy patients have had seizures. However, because of the aforementioned Henry's Law effect of extra available dissolved oxygen to neurons, there is usually no negative sequel to the event. Such seizures are generally a result of oxygen toxicity,[25][26] although hypoglycemia may be a contributing factor, but the latter risk can be eradicated or reduced by carefully monitoring the patient's nutritional intake prior to oxygen treatment.

Oxygen first aid has been used as an emergency treatment for diving injuries for years.[27] Recompression in a hyperbaric chamber with the patient breathing 100% oxygen is the standard hospital and military medical response to decompression illness.[27][28][29] The success of recompression therapy as well as a decrease in the number of recompression treatments required has been shown if first aid oxygen is given within four hours after surfacing.[30] There are suggestions that oxygen administration may not be the most effective measure for the treatment of decompression illness and that heliox may be a better alternative.[31]

Chronic obstructive pulmonary disease

Care needs to be exercised in patients with chronic obstructive pulmonary disease, such as emphysema, especially in those known to retain carbon dioxide (type II respiratory failure). Such patients may further accumulate carbon dioxide and decreased pH (hypercapnation) if administered supplemental oxygen, possibly endangering their lives.[32] This is primarily as a result of ventilation–perfusion imbalance (see Effect of oxygen on chronic obstructive pulmonary disease).[33] In the worst case, administration of high levels of oxygen in patients with severe emphysema and high blood carbon dioxide may reduce respiratory drive to the point of precipitating respiratory failure, with an observed increase in mortality compared with those receiving titrated oxygen treatment.[32] However, the risk of the loss of respiratory drive are far outweighed by the risks of withholding emergency oxygen, and therefore emergency administration of oxygen is never contraindicated. Transfer from field care to definitive care, where oxygen use can be carefully calibrated, typically occurs long before significant reductions to the respiratory drive.

A 2010 study has shown that titrated oxygen therapy (controlled administration of oxygen) is less of a danger to COPD patients and that other, non-COPD patients, may also, in some cases, benefit more from titrated therapy.[32]

Fire risk

Highly concentrated sources of oxygen promote rapid combustion. Oxygen itself is not flammable, but the addition of concentrated oxygen to a fire greatly increases its intensity, and can aid the combustion of materials (such as metals) which are relatively inert under normal conditions. Fire and explosion hazards exist when concentrated oxidants and fuels are brought into close proximity; however, an ignition event, such as heat or a spark, is needed to trigger combustion.[34] A well-known example of an accidental fire accelerated by pure oxygen under pressure occurred in the Apollo 1 spacecraft in January 1967 during a ground test; it killed all three astronauts. A similar accident killed Soviet cosmonaut Valentin Bondarenko in 1961.

Combustion hazards also apply to compounds of oxygen with a high oxidative potential, such as peroxides, chlorates, nitrates, perchlorates, and dichromates because they can donate oxygen to a fire.

Concentrated O
2
will allow combustion to proceed rapidly and energetically.[34] Steel pipes and storage vessels used to store and transmit both gaseous and liquid oxygen will act as a fuel; and therefore the design and manufacture of O
2
systems requires special training to ensure that ignition sources are minimized.[34] Highly concentrated oxygen in a high-pressure environment can spontaneously ignite hydrocarbons such as oil and grease, resulting in fire or explosion. The heat caused by rapid pressurization serves as the ignition source. For this reason, storage vessels, regulators, piping and any other equipment used with highly concentrated oxygen must be "oxygen-clean" prior to use, to ensure the absence of potential fuels. This does not apply only to pure oxygen; any concentration significantly higher than atmospheric (approximately 21%) carries a potential risk.

Hospitals in some jurisdictions, such as the UK, now operate “no-smoking” policies, which although introduced for other reasons, supports the aim of keeping ignition sources away from medical piped oxygen. Other recorded sources of ignition of medically prescribed oxygen include candles, aromatherapy, medical equipment, cooking, and unfortunately, deliberate vandalism. Smoking pipes, cigars and cigarettes are of special concern. This does not entirely eliminate the risk of injury with portable oxygen systems, especially if compliance is poor.[35]

In alternative medicine

Some practitioners of alternative medicine have promoted "oxygen therapy" as a cure for many human ailments including AIDS, Alzheimer's disease and cancer. The procedure may include injecting hydrogen peroxide, oxygenating blood, or administering oxygen under pressure to the rectum, vagina, or other bodily opening. According to the American Cancer Society, "available scientific evidence does not support claims that putting oxygen-releasing chemicals into a person's body is effective in treating cancer", and some of these treatments can be dangerous.[36]

Oxygen therapy while on aircraft

In the United States, most airlines restrict the devices allowed on board aircraft. As a result passengers are restricted in what devices they can use. Some airlines will provide cylinders for passengers with an associated fee. Other airlines allow passengers to carry on approved portable concentrators. However the lists of approved devices varies by airline so passengers need to check with any airline they are planning to fly on. Passengers are generally not allowed to carry on their own cylinders. In all cases, passengers need to notify the airline in advance of their equipment.

Effective May 13, 2009, the Department of Transportation and FAA ruled that a select number of portable oxygen concentrators are approved for use on all commercial flights.[37] The list of approved portable oxygen concentrators includes the Respironics EverGo, the Invacare XPO2, the Invacare Solo 2 and others.[38]

FAA regulations require larger airplanes to carry D-cylinders of oxygen for use in an emergency.

See also

References

  1. ^ a b c "Clinical Guidelines Update — Oxygen" (PDF). Joint Royal Colleges Ambulance Liaison Committee/Warwick University. April 2009. Retrieved 2009-06-29.
  2. ^ McDonald, Christine F; Crockett, Alan J; Young, Iven H (2005). "Adult domicilariary oxygen. Position statement of the Thoracic Society of Australia and New Zealand". The Medical Journal of Australia. 182 (12): 621–6.
  3. ^ Stoller, JK.; Panos, RJ.; Krachman, S.; Doherty, DE.; Make, B. (Jul 2010). "Oxygen therapy for patients with COPD: current evidence and the long-term oxygen treatment trial". Chest. 138 (1): 179–87. doi:10.1378/chest.09-2555. PMID 20605816.
  4. ^ "Continuous or nocturnal oxygen therapy in hypoxemic chronic obstructive lung disease: a clinical trial. Nocturnal Oxygen Therapy Trial Group". Ann Intern Med. 93 (3): 391–8. Sep 1980. doi:10.7326/0003-4819-93-3-391. PMID 6776858.
  5. ^ Abernethy, Amy (4 September 2010). "Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: a double-blind, randomised controlled trial". Lancet. 376 (9743): 784–793. doi:10.1016/S0140-6736(10)61115-4. PMC 2962424. PMID 20816546. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  6. ^ O'Driscoll BR; Howard LS; Davison AG (October 2008). "BTS guideline for emergency oxygen use in adult patients" (PDF). Thorax (pdf). 63 (Suppl 6:vi). British Thoracic Society: 1–68. doi:10.1136/thx.2008.102947. PMID 18838559.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. ^ Sands, George. "Oxygen Therapy for Headaches". Retrieved 2007-11-26.
  8. ^ a b American College of Chest Physicians; American Thoracic Society (September 2013), "Five Things Physicians and Patients Should Question", Choosing Wisely: an initiative of the ABIM Foundation, American College of Chest Physicians and American Thoracic Society, retrieved 2013-01-06, which cites
  9. ^ "Luxfer Aluminum Oxygen Cylinders". CPR Savers & First Aid Supply. Retrieved 2010-04-18.
  10. ^ McCoy, Robert. "Portable Oxygen Concentrators (POC) Performance Variables that Affect Therapy" (pdf). Retrieved 2007-07-03.
  11. ^ Evaluation of the System O2 Inc Portable Nonpressurized Oxygen Delivery System
  12. ^ Kallstrom 2002
  13. ^ Garcia JA, Gardner D, Vines D, Shelledy D, Wettstein R, Peters J (October 2005). "The Oxygen Concentrations Delivered by Different Oxygen Therapy Systems". Chest Meeting. 128 (4): 389S–390S. doi:10.1378/chest.128.4_meetingabstracts.389s-b.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  14. ^ Earl, John. Delivery of High FiO
    2
    . Cardinal Health Respiratory Abstracts.
  15. ^ Accurate Oxygen Delivery
  16. ^ Sim, DA; Dean, P; Kinsella, J; Black, R; Carter, R; Hughes, M (September 2008). "Performance of oxygen delivery devices when the breathing pattern of respiratory failure is simulated". Anaesthesia. 63 (9): 938–40. doi:10.1111/j.1365-2044.2008.05536.x. PMID 18540928.
  17. ^ Roca O, Riera J, Torres F, Masclans, JR. (April 2010). "High-flow oxygen therapy in acute respiratory failure". Respiratory Care. 55 (4): 408–13. PMID 20406507.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  18. ^ Cyanide poisoning — New recommendations on first aid treatment
  19. ^ Hui DS, Hall SD, Chan MT; et al. (August 2007). "Exhaled air dispersion during oxygen delivery via a simple oxygen mask". Chest. 132 (2): 540–6. doi:10.1378/chest.07-0636. PMID 17573505. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  20. ^ Mardimae A, Slessarev M, Han J; et al. (October 2006). "Modified N95 mask delivers high inspired oxygen concentrations while effectively filtering aerosolized microparticles". Annals of Emergency Medicine. 48 (4): 391–9, 399.e1–2. doi:10.1016/j.annemergmed.2006.06.039. PMID 16997675. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  21. ^ Somogyi R, Vesely AE, Azami T; et al. (March 2004). "Dispersal of respiratory droplets with open vs closed oxygen delivery masks: implications for the transmission of severe acute respiratory syndrome". Chest. 125 (3): 1155–7. doi:10.1378/chest.125.3.1155. PMID 15006983. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  22. ^ Patarinski, D (1976). "Indications and contraindications for oxygen therapy of respiratory insufficiency". Vŭtreshni bolesti (in Bulgarian with English abstract). 15 (4): 44–50. PMID 1007238.{{cite journal}}: CS1 maint: unrecognized language (link)
  23. ^ Experience with paraquat poisoning in a respiratory intensive care unit in North India
  24. ^ "EMT Medication Formulary" (PDF). PHECC Clinical Practice Guidelines. Pre-Hospital Emergency Care Council. 15 July 2009. p. 84. Retrieved 2010-04-14.
  25. ^ Smerz, R.W. (2004). "Incidence of oxygen toxicity during the treatment of dysbarism". Undersea and Hyperbaric Medicine. 31 (2): 199–202. PMID 15485081. Retrieved 2008-04-30.
  26. ^ Hampson, Neal B.; Simonson, Steven G.; Kramer, C.C.; Piantadosi, Claude A. (1996). "Central nervous system oxygen toxicity during hyperbaric treatment of patients with carbon monoxide poisoning". Undersea and Hyperbaric Medicine. 23 (4): 215–9. PMID 8989851. Retrieved 2008-04-29.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  27. ^ a b Brubakk, A. O. (2003). Bennett and Elliott's physiology and medicine of diving, 5th Rev ed. United States: Saunders Ltd. p. 800. ISBN 0-7020-2571-2. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  28. ^ Undersea and Hyperbaric Medical Society. "Decompression Sickness or Illness and Arterial Gas Embolism". Retrieved 2008-05-30.
  29. ^ Acott, C. (1999). "A brief history of diving and decompression illness". South Pacific Underwater Medicine Society Journal. 29 (2). ISSN 0813-1988. OCLC 16986801. Retrieved 2008-05-30.
  30. ^ Longphre, J. M. (2007). "First aid normobaric oxygen for the treatment of recreational diving injuries". Undersea Hyperb Med. 34 (1): 43–49. ISSN 1066-2936. OCLC 26915585. PMID 17393938. Retrieved 2008-05-30. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  31. ^ Kol S, Adir Y, Gordon CR, Melamed Y (June 1993). "Oxy-helium treatment of severe spinal decompression sickness after air diving". Undersea Hyperb Med. 20 (2): 147–54. PMID 8329941. Retrieved 2008-05-30.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  32. ^ a b c Austin, Michael A; Wills, Karen E; Blizzard, Leigh; Walters, Eugene H; Wood-Baker, Richard (18 October 2010). "Effect of high flow oxygen on mortality in chronic obstructive pulmonary disease patients in prehospital setting: randomised controlled trial". British Medical Journal. 341 (oct18 2): c5462. doi:10.1136/bmj.c5462. ISSN 0959-8138. PMC 2957540. PMID 20959284.
  33. ^ Kim, Victor; Benditt, Joshua O; Wise, Robert A; Sharafkhaneh, Amir (2008). "Oxygen therapy in chronic obstructive pulmonary disease". Proceedings of the American Thoracic Society. 5 (4): 513–8. doi:10.1513/pats.200708-124ET. PMC 2645328. PMID 18453364.
  34. ^ a b c Werley, Barry L. (Edtr.) (1991). "Fire Hazards in Oxygen Systems". ASTM Technical Professional training. Philadelphia: ASTM International Subcommittee G-4.05. {{cite conference}}: Unknown parameter |booktitle= ignored (|book-title= suggested) (help)
  35. ^ Lindford AJ, Tehrani H, Sassoon EM, O'Neill TJ (June 2006). "Home Oxygen Therapy and Cigarette Smoking: A Dangerous Practice". Annals of Burns and Fire Disasters. 19 (2).{{cite journal}}: CS1 maint: multiple names: authors list (link)
  36. ^ "Oxygen Therapy". American Cancer Society. 26 December 2012. Retrieved 2013-09-20.
  37. ^ "FAA Approved Portable Oxygen Concentrators - Positive Testing Results". faa.gov. Retrieved 2014-06-22.
  38. ^ http://www.open-aire.com/rentalcenter/

Further reading

Template:Cardiopulmonary therapy