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Emergence Phenomenon?[edit]

I was redirected to this page from Emergence Phenomenon, but emergence phenomena are not discussed on this page at all! —Preceding unsigned comment added by (talk) 16:42, 18 September 2008 (UTC)

Likewise. Checking the original article's history I found a definition for Emergence Phenomenon as "In medicine, emergence phenomena are reactions experienced by patients during or after awakening from anaesthesia". Perhaps it would be more useful to redirect that page to a link in Wiktionary for this term? Either that, or please include the definition of the term on the Anesthesia page! --Fjb3 (talk) 00:29, 17 May 2009 (UTC)

And same here. It would be helpful if this term was explained. —Robotech_Master (talk) 03:03, 25 August 2009 (UTC)
It's still not mentioned in the page. Even a copy paste of the definition here would be nice in the page. (talk) 20:22, 15 October 2009 (UTC)
I have added a (very) brief section describing emergence phenomena in the general anaesthesia article, which is a more appropriate place for that discussion than in this article IMHO. I have also rewritten the disambiguation page for emergence. I hope this helps. DiverDave (talk) 04:08, 27 December 2010 (UTC)

More vandals.[edit]

To those who are now attempting to edit the CRNA section to reflect YOUR politics, (anonymous IPs), it has been mandated by the staff of wiki that no changes are to be made without discussion here and agreement. I am the default protector of the CRNA section in this wiki entry and keep it from being politicized by ASA peons. Please, keep YOUR politics out of my section. Thanks,Mmackinnon (talk) 02:20, 15 June 2009 (UTC)

Editing an article by adding sourced information and removing unsourced information is not vandalism, but good editing. Claiming the article should remain as you left it is ownership, and violates wikipedia policy [[1]]. If you and your sockpuppets are willing to have adult conversations and compromises on language that is one thing, crying vandalism everytime someone adds to an article you believe you own is another. Fuzbaby (talk) 01:27, 16 June 2009 (UTC)

info for fuzbaby[edit]

Hello there

First, I am always suspicious (after 3 years) of people who come here making random edits without using the talk page. It suggests ulterior motives. Having said that, here is the reason why your edit is incorrect.

You had edited "CRNAs do not require Anesthesiologist supervision in any state and require surgeon/dentist/podiatrists to sign and approve the chart for medicare billing in all but 16 states. Many states place restrictions on practice, and hospitals often regulate what CRNAs can or can not do."

Here is what was stated previously: "CRNAs do not require Anesthesiologist supervision in any state and only require surgeon/dentist/podiatrists to sign the chart for medicare billing in all but 16 states."

The difference here is significant. First, noone is required to "approve" anything a CRNAs does by law or state law. Hospital policy may be different in each hospital as it IS for all physicians as well. So that statement, which makes the suggestion that CRNAs are somehow limited in comparison, is not needed since it also applies to physicians. In otherwords, it goes without saying. CRNAs are not the same an NPs in that regard. Second, the requirement to sign the chart ONLY exists as a CMS requirement for billing. In every state in the union CRNAs work independently in ASCs like plastic surgery centers, where it is an all cash buisness and CRNAs require noone to sign their chart. There is no "approval" of anything the CRNA does by a physician. This is a misconception.

The actual document says this:

"Thirty-nine states do not have a physician "supervision" requirement for CRNAs in nursing or medical laws or regulations. If clinical "direction" requirements are considered in addition to "supervision," 31 states do not have a physician supervision or direction requirement for CRNAs in nursing or medical laws or regulations. Taking into account state hospital licensing laws or regulations as well, 33 states still do not require physician supervision. Taking into account state hospital licensing laws or regulations, 24 states still do not require physician supervision or direction."

The states which do have some language are left intentionally grey as the expert for anesthesia services is the CRNA and not the operating physician. Case law has proven that in every case, the CRNA working independently (including in supervision states) is 100% liable for the anesthetic and surgeons do not get sued any more often with CRNA only vs MDA only practice. Surgeons carry ZERO additional liability for working with a CRNA.

So the term "supervision" becomes very negative when in reality it means nothing but signing a chart and no actual supervision or direction is required. That is the reason I leave the word out since in reality it has a different meaning that what people would take it as. The reality is this is ONLY about a billing situation.

Comments?Mmackinnon (talk) 18:34, 15 June 2009 (UTC)

Hello, let me start out that users who claim ownership and leave personal attack on personal pages, as you did, are rarely honest, neutral editors.

Second, the source states: "The federal requirement has been that CRNAs must be supervised by a physician. The November 13, 2001 rule allows states to "opt-out" or be "exempted" (the terms are used synonymously in the November 13 rule) from the federal supervision requirement"...further "14 states as of June 2005)

Iowa opted out of the federal supervision requirement in December 2001. Nebraska opted out in February 2002. Idaho opted out in March 2002. Minnesota opted out in April 2002. New Hampshire opted out in June 2002. New Mexico opted out in November 2002. Kansas opted out in March 2003. North Dakota opted out in October 2003. Washington opted out in October 2003. Alaska opted out in October 2003. Oregon opted out in December 2003. Montana opted out in January 2004. (Gov. Judy Martz opted-out; Gov. Brian Schweitzer reversed the opt-out in May 2005, without citing any evidence to justify the decision. Subsequently, after the governor and his staff became more familiar with the reasons justifying the January 2004 opt-out, Gov. Schweitzer restored the opt-out in June 2005. Montana’s opt-out, therefore, is currently in effect.) South Dakota opted out in March 2005. Wisconsin opted out in June 2005." and: "18 states permit CRNAs to practice "independently."" This is not consistent to what is stated in this and other articles on this topic. Fuzbaby (talk) 01:21, 16 June 2009 (UTC)

First, I deleted a post I made out of frustration on your talk page before i actually posted it. However, your attempt at an ad hominem is noted. In anycase, you clearly do not understand the difference between CMS rules for participation in medicare and how they use the terms medical direction and supervision. CRNAs can practice independently in every state in the union this has ALWAYS been true. The CMS rules also state "supervision and medical direction are not comments or direction in relation to scope of practice or control". These are billing terms which explain WHAT and anesthesiologist must do in order to get paid for their participation in the anesthetic (if they are there). Supervision by the operating practitioner involves only them signing an ORDER for anesthesia to be delivered in order for the CRNA to collect 100% physician fee schedule for medicaid. There is no requirement otherwise for 'supervision'. So what you have edited in inaccurate since you suggest supervision as much more than a billing term and that independent practice (billing without someone signing) has anything to do with scope of practice or practice environment. This is simply not the case. Please show me where the term "and approve" is used in that document. Also please explain this statement

"Many states place restrictions on practice, and hospitals often regulate what CRNAs and other midlevel providers can or can not do based on local laws, provider training and experience, and hospital and physician preferences"

I do not fund this in the article either. Moreover, this is also true for every practitioner including physicians. Please show me where it states there is any requirement for "physician preference" as well. I do not find this in the article nor do i find that there is any difference in these requirements for CRNAs as there are for physician requirements. They too have to deal with state laws, hospital policy, local laws, training and experience and hospital preference. Why did you not add this also in the physician section? This seems biased. Please defend these changes. As was agreed to by the moderators previously in this discussion page this is vandalism without proper consensus or discussion.Mmackinnon (talk) 03:18, 16 June 2009 (UTC)

Proposal to split Anesthetic agents to separate article[edit]

This article is getting rather long, and to mirror other medical fields on Wikipedia, I propose that the "Anesthetic agents" section be split to its own article. Almost all drug groups have their own articles, separate from the field of medicine that uses the drugs (see {{Major drug groups}}). There used to be an article called Anaesthetic drugs, but it was moved to List of anaesthetic drugs. What I propose is merging the "Anesthetic agents" section of this article with List of anaesthetic drugs, and then moving the article to Anesthetic. Anesthesia/Anesthetic would then parallel the related articles local anesthesia/local anesthetic and general anesthesia/general anesthetic. A {{main}} link to Anesthetic with an overview summary would then be placed in the "Anesthetic agents" section of this article. --Scott Alter 18:08, 20 June 2009 (UTC)

Anyone have any comments? --Scott Alter 00:12, 5 July 2009 (UTC)

Since there were no objections, I completed this split. The article is currently at List of anaesthetic drugs, until an admin deletes Anesthetic so List of anaesthetic drugs can be moved there. --Scott Alter 17:23, 8 September 2009 (UTC)


NYCMD, it is not your place to delete valid references from this article. Nor is it your place to edit the Nurse Anesthesia section because it does not fit your personal opinions. Moreover, is an ASA owned website and by definition biased. It isnt a reference, simply a page for ASA agenda. Mmackinnon (talk) 03:03, 11 May 2010 (UTC)

article reassessment[edit]

This article has significant problems related to MoS compliance, content (e.g., the prose is riddled with grammatical and spelling errors) and referencing (e.g., the article is nearly devoid of reliable sources). Due to these issues, I have reassessed this article as Start class. There is also a long history of NPOV issues, edit wars, vandalism, and heavy use of edit reversions. This article is greatly in need of attention from expert editors and any other interested editors. Respectfully, DiverDave (talk) 05:30, 10 September 2010 (UTC)

Horace Wells[edit]

I think Dr. Horace Wells should be mentioned in this article. He gave an unsuccessful demonstration of laughing gas with a dental patient in MGH and was booed at. But he was a pioneer of anesthesiology also. — Preceding unsigned comment added by (talk) 23:24, 2 October 2011 (UTC)

Types of Anaesthesia[edit]

Classification has to be refined to only two broad groups such as 1)General and 2)Regional. Further Regional anesthesia is to be divided into a.Spinal anesthesia, b.Epidural anesthesia, c.Nerve Blocks, d.Bier's Block (IV Regional anesthesia), e.Field block, f.Local infiltration. Dissociative anesthesia is a type of phenomenon caused by specific drug such as ketamine to induce painlessness. It comes under the classification of Total Intravenous anesthesia (TIVA) which is a sub-group under general anaesthesia.Drvijay2000 (talk) 17:13, 22 December 2011 (UTC)

Raymond Lullus?[edit]

There is no citation for the section about Raymond Lullus first discovering ether. His wikipedia page makes no mention. Other sources -- including Cordas' wikipedia page -- say it was first synthesized by Valerius Cordas in 1570 when he mixed ethanol and sulfuric acid, calling the result "Sweet Oil of Vitriol."Msalt (talk) 21:52, 26 April 2012 (UTC)

OMFS section[edit]

The discussion of OMFS in this detail is WP:UNDUE weight. All surgical residencies, as well as many internal medicine subspecialties, are trained in administering anesthetic medications. However, this is not the place to discuss one specific surgical subspecialty, but to discuss those providers whose primary roles are to provide anesthesia related medciations (such as anesthesiologists, CRNAs, etc). I would not mind a section, appropriately sourced and weight to describe that physicians in general can be trained in administering anesthetics such as critical care physicians, etc., but the section as written was completely UNDUE and reads like an advertisement for the OMFS subspecialty. Yobol (talk) 22:25, 8 July 2012 (UTC)

Improving article[edit]

Looking to see who is active on this article. I started looking to see where people land when investigating basic medical topics and this is a popular landing page for anesthesia related topics. However, it seems largely to be a discuss/debate about the role of various professionals who provide anesthesia rather than anaesthesia itself. I'd like to rework the article following the basic Surgeries and procedures MEDMOS outline and putting the Outline of anesthesia into the narrative so people can link to the specific topic needed. Would people be opposed to this? Anyone wanting to help? Thanks. Ian Furst (talk) 18:43, 8 February 2014 (UTC)

I am very much in favor of your proposal, and I would be most happy to collaborate if you wish. And yes, the article should follow Surgeries and procedures MEDMOS and should be focused on the topic of anesthesia and not on who provides it. DiverDave (talk) 03:46, 9 February 2014 (UTC)

My plan is to use the following MEDMOS heading structure listed below. Sources in this article are mostly primary and need to be changed to secondary. My main resource will be Miller's Anes 2009 to start with a planned change to sources available online with time. I'll also be making a conscious effort to include as many of the Wikilinks listed in the Outline of anesthesia as possible (without making the article look link a link-farm). My first priority is to create a scope more directed to the user.

  • Indications
Discussion of sleep memory and consciousness
  • Contra-indications
I don't think I'll include this heading as there's no easy way to word the relative contraindications on all techniques for the layperson, will overexpand risk/complications to cover this
  • Technique
various techniques, spinal, regional, GA, sedation, etc...
  • Risks/Complications
summary of Ch33 from Miller's
  • Recovery or Rehabilitation
Post-op management nv, acute pain, cogn dysfunc and confusion and po vision loss
  • History (e.g., when it was invented)
as is with primary sources replaced
  • Society and culture (includes legal issues, if any)
providers discussion (may have WP:WEIGHT issue)
  • Special populations
discussion of various subspecialties, populations or technique - basically the chapter headings Ch 58-84 in Millers
  • Other animals
links to veterinary anes

Please jump in if you feel these ideas need to be modified. Ian Furst (talk) 13:05, 9 February 2014 (UTC)

First bits of revision[edit]

I've started changing the article. See Anesthesia#indication to see the general tone I'm proposing. Very general with lots of links to relevant information. Looking for feedback from other editors. Thanks. @DiverDave: Ian Furst (talk) 16:44, 9 February 2014 (UTC)

2nd bits of revision[edit]

The overall outline, headings and general themes are now created. My next step will be to copy edit, improve the language so it's geared more towards the layperson, diversify the references (so far I've relied heavily on Miller's Anesthesia) and add some graphs or tables especially in the Risks and complications section. Ian Furst (talk) 13:24, 16 February 2014 (UTC)

3rd bits of revision[edit]

I've now got the article to, what I believe is, the appropriate weight and scope for each area. I'll continue with general copy editing and adding in references. A graph for risk and complication turned out to be useless (it's misleading to compare M&M over the years due to risk stratification of patients). If anyone can see where a graphic might better add to the story please let me know and I'll try to create it. 13:55, 17 February 2014 (UTC)


Upgrading this article to B-class now. I think it follows MEDMOS for the most part, has 1/2 decent references (although I'd like to add more online stuff) and I think the scope is OK. Please leave feedback if you see areas for improvement. Ian Furst (talk) 02:30, 22 February 2014 (UTC)

  • I still haven't updated the opening section; waiting until the scope of the rest of the article is set, then will update and improve. Ian Furst (talk) 03:15, 22 February 2014 (UTC)

General comments[edit]

Axl - Thank you very much for going through this for me. Most of the info comes from Miller’s Anesthesia (the “go-to” reference for anesthesia). See discussion below and happy to discuss further, Ian Furst (talk) 15:39, 22 February 2014 (UTC)

From the lead section, paragraph 2: "Local anesthesia inhibits sensory perception within a specific location on the body, such as a tooth or the urinary bladder." Why is the urinary bladder suggested a location for local anaesthesia? Axl ¤ [Talk] 12:55, 22 February 2014 (UTC)

Cystoscopy, This is what happens when someone focused on the HN uses a general anaesthesia text. It’s a weird combo for wiki and I’ll change it. Ian Furst (talk) 15:39, 22 February 2014 (UTC) Yes check.svg Done Ian Furst (talk) 21:27, 22 February 2014 (UTC)

The opening sentence of "Medical uses" implies analgesia. However "analgesia" is repeated in the list of five bullet points. Axl ¤ [Talk] 13:03, 22 February 2014 (UTC)

I’m trying to create a framework for the layperson by stating what I think a layperson would perceive as the rationale for anaesthesia (“I don’t want it to hurt) with what the clinician needs (5 points). I’ll have to think of a less specific way to orientate the reader in the first sentence. I didn’t want to start off with a technical list. Ian Furst (talk) 15:39, 22 February 2014 (UTC)

In "Medical uses", "immobility (lack of movement)" is not accurate. Immobility could perhaps be achieved with restraints (maybe like prisoner restraints?). The phrase should properly be "muscle relaxation". When the surgeon's scalpel cuts, the muscles will reflexively contract. Muscle relaxation is required to prevent this and make the surgeon's job easier. Muscle relaxation is an important part of general anaesthesia, but it hasn't been mentioned anywhere in the article. Axl ¤ [Talk] 13:11, 22 February 2014 (UTC)

Immobility comes straight from Miller. Generally, when anesthetists refer to muscle relaxation they’re talking about paralytics like sux/roc/whatever which aren’t always used. For much of our head and neck stuff, they don’t give it unless the patient is “fighting” the vent. Whereas in abd sx, they almost always have to give it to retract the abd wall. Surgery, may require immobility but not always muscle relaxation. I’m pretty sure this is the correct term. Ian Furst (talk) 15:39, 22 February 2014 (UTC)

From "Medical uses", paragraph 4: "More important to the patient, is the loss of any memory of the events (amnesia)." Is that really more important to the patient? Axl ¤ [Talk] 13:13, 22 February 2014 (UTC)

Good point, too subjective. Again, I’m trying to orientate the reader before getting into the technical jargon of hypnosis v amnesia. Will change. Ian Furst (talk) 15:39, 22 February 2014 (UTC) Yes check.svg Done

From "Medical uses", paragraph 4: "Inhalational anesthetics will reliably produce amnesia though general suppression of the nuclei but at doses well above those required for loss of consciousness." Is that really true? Inhalational anaesthetics will cause unconsciousness but without causing loss of memory? Axl ¤ [Talk] 13:16, 22 February 2014 (UTC)

No it’s not, thank you. I mis-read the paragraph as “For the volatile anesthetics, memory formation is impaired at drug concentrations between a 25% and 50%” (which is a high dose) but it was actually, “....25% and 50% of the minimum alveolar concentration (MAC)” This is a long section in Miller on memory formation (and how BZD’s differ from volatile agents) and consciousness during anesthesia. I’ll reword it. Ian Furst (talk) 15:39, 22 February 2014 (UTC) Yes check.svg Done

In the "Medical uses" section, I am not convinced that amnesia is an important part of anaesthesia. Amnesia is listed first in the bullet points, and a paragraph about it comes before unconsciousness. Certainly amnesia is a useful side-effect in certain unpleasant wakeful procedures such as endoscopy, but is this really a part of anaesthesia? Axl ¤ [Talk] 13:25, 22 February 2014 (UTC)

I’ve listed them in the same order as Miller. Sleep, memory and consciousness are major aspects of anesthetic physiology but tightly related and evolving research fields (see next question below for more on this). Awareness under GA (which may actually have more to do with consciousness than memory, but that’s splitting hairs) is a significant concern. Again, Miller lists it implicitly (first) as one of the endpoints of anesthesia. From everything I read and from the perspective of patients many of whom say their main goal is that they don’t want to remember anything, I think it’s important and a major part of anesthesia imo. Ian Furst (talk) 15:39, 22 February 2014 (UTC)
"many of whom say their main goal is that they don’t want to remember anything." Even if they say that, is that really what they mean? If anaesthesia involved strapping people down and causing extreme pain without analgesia, but with subsequent amnesia, would that be acceptable? Axl ¤ [Talk] 22:27, 22 February 2014 (UTC)
Not at all. By the same logic would anesthesia with immobility, analgesia, hemodynamic stability and muscle relaxation be acceptable if the patients' have recollection of the events? I've emailed the author of the chapter to ask for more info on the distinction between hypnosis, amnesia and lack of consciousness. Hopefully his input will make it easier to draw the distinctions. I assume we can both agree that a lack of awareness is an end point of general anesthesia. From your responses, am I to understand that you believe a hypnotic state includes amnesia and a lack of consciousness?Ian Furst (talk) 22:43, 22 February 2014 (UTC)
"By the same logic would anesthesia with immobility, analgesia, hemodynamic stability and muscle relaxation be acceptable if the patients' have recollection of the events?" Definitely yes. Consider every form of local and regional anaesthesia. Axl ¤ [Talk] 22:58, 22 February 2014 (UTC)
"am I to understand that you believe a hypnotic state includes amnesia and a lack of consciousness?" No. Amnesia is the loss of memory. If there was no perception of the event (such as a stimulus) to begin with, there can be no memory of it to be lost, therefore amnesia is irrelevant. During hypnosis (anaesthetic hypnosis), perceptions are not achieved, therefore amnesia is irrelevant. In the context of anaesthesia, amnesia is only relevant for wakeful procedures (local/regional anaesthesia).
My understanding of unconsciousness (in the medical sense) is that it requires lack of perception of all stimuli. From reading your definition of hypnosis: "Hypnosis is defined as a lack of perceptive awareness to non-noxious stimuli", I think that unconsciousness also requires the lack of perception of noxious stimuli—i.e. analgesia. Hypnosis does not inherently include analgesia, which is why analgesia is required alongside hypnosis. Anaesthetic unconsciousness could be regarded as the combination of hypnosis with analgesia. Axl ¤ [Talk] 00:01, 23 February 2014 (UTC)

──────────────────────────────────────────────────────────────────────────────────────────────────── I checked 2 other e-books and can't find the endpoints listed. I found this article that lists them as hypnosis, analgesia, amnesia and reflex suppression (it's a study using fMRI so maybe the didn't use muscle relaxation as an endpoint?). I'll keep looking. Imo, the endpoints should all be met for a full GA and at least one of them met for other types of anesthesia. E.g. LA hit analgesia alone. What do you think the end points should be (and can you give me a reference for them)? Agree that hypnosis and analgesia need to go together. But what is awareness under GA?. What is dreaming under GA? Ian Furst (talk) 13:44, 23 February 2014 (UTC)

So far, I have not looked in any sources. (I was kinda hoping that you would quote the definitions and correct my mistakes.) But I am happy to look in some sources. I shall see what I can find. Axl ¤ [Talk] 01:02, 24 February 2014 (UTC)
Can you give me a page number/chapter for Miller's Anesthesia please? Axl ¤ [Talk] 16:48, 24 February 2014 (UTC)

Is anaesthetic hypnosis truly different from unconsciousness? Axl ¤ [Talk] 13:26, 22 February 2014 (UTC)

That is an extremely tough question for me to answer. In my mind, sleep, hypnosis and consciousness (as they related to anesthesia) are all tightly related with large overlap. Hypnosis is defined as a lack of perceptive awareness to non-noxious stimuli. Consciousness is the capacity for neural systems to synthesize information (the ability to generate a unified perception from various sensory inputs). I’m not sure a hypnotic state is synonymous with a lack of consciousness to noxious stimuli (which is a desired result of anesthesia). Consciousness is a newer research field in anesthesia. I could try and track down of the authors of the chapter in Miller and ask. Which part of the article triggered the question? Ian Furst (talk) 15:39, 22 February 2014 (UTC)
"lack of consciousness to noxious stimuli." Using your previous definition of "consciousness", that statement is meaningless. Perhaps you meant "lack of perception of noxious stimuli"? Otherwise known as "analgesia". Axl ¤ [Talk] 22:47, 22 February 2014 (UTC)

Another general comment about the "Medical uses" section: when I was a student, I learnt that anaesthesia focussed on three aspects—analgesia, hypnosis and muscle relaxation. While that view may be a little simplistic, it would be a good rule to focus on those three features in this Wikipedia article. Axl ¤ [Talk] 13:29, 22 February 2014 (UTC)

I can change the focus. Keep in mind, historically, death from shock secondary to uncontrolled automatic responses during surgery was a major issue before Harvey Cushings work. Even if it’s not evident to the patient, it’s still a major issue. As already discussed, I need to get more info on hypnosis v amnesia. Ian Furst (talk) 15:39, 22 February 2014 (UTC)

Hypnosis, unconsciousness and amnesia[edit]

Axl From one of the authors of Millers who coauthored the relevant chapter,

Thanks for contacting me. I'm happy to help clarify. In anesthesiology, when we discuss the term "hypnosis" it is used to describe the loss of consciousness endpoint. While there are many uses of term hypnosis, especially in psychology, we mean to imply the drug-induced state that causes a loss of consciousness. The presence or absence of memory (amnesia) can be completely dissociated from the loss of consciousness. However, you are correct that the loss of consciousness necessarily induces a loss of memory. I agree with the notion that anesthesia at its core can be distilled into hypnosis, analgesia, and muscle relaxation. However, there are some who would disagree with me and say that true core of anesthesia is merely amnesia, muscle relaxation, and analgesia and does not require unconsciousness. Rarely, in the setting of trauma that is life-threatening, anesthesiologists will induce a state that is merely amnesia and muscle relaxation. Once again, let me stress that this is only done during conditions when the adverse side effects of using a drug that would cause hypnosis (ie: further low blood pressure) might lead to death.

Ian Furst (talk) 22:03, 23 February 2014 (UTC)

Thank you for posting his response (and thanks to him for replying). It is interesting to see that he equates hypnosis with loss of consciousness. This definition of hypnosis seems to be slightly different to the one that you quoted above. Consider this: can a noxious stimulus (i.e. pain) be perceived by a person in hypnosis?
Follow-up email (just got a response) asked him about the differing definitions of hypnosis. Specifically if the one from the book (and that I used) would still apply. His response, "Yes, I wrote the "lack of perceptive awareness to non-noxious stimuli" simply to imply that the presence/absence of consciousness must be done in the absence of painful stimuli." Presumably, the presence of noxious stimuli will change the threshold for consciousness? Ian Furst (talk) 01:13, 24 February 2014 (UTC)
He also describes the absence of memory as amnesia. If a person has never experienced an event, he has no memory of that event. However that absence of memory is not amnesia. With respect to the author, the definition should be loss of memory, not absence of memory. Axl ¤ [Talk] 00:30, 24 February 2014 (UTC)
It may depend on the drugs being used. I believe inhalation anesthetics globally suppress nuclei so memories are not formed (and at 25-50% of MAC, doses unlikely to cause hypnosis). In this case, there may not be hypnosis but there will be amnesia and, I don't think the memories ever formed. Benzodiazapines, on the other hand, will block the transition from short-term to long-term memories. So they're lost. I can give midazolam, fentanyl and LA (a common sedation), complete a procedure with the patient quite conscious but they have no memory or the event. The same with ketamine and local. Which end points did I hit? Analgesia for sure. But what else? Based on the new definition of hypnosis, I have not achieved it. Ian Furst (talk) 01:13, 24 February 2014 (UTC)
Maybe the way to frame it is that hypnosis will include amnesia but amnesia may not be associated with hypnosis. Ian Furst (talk) 01:15, 24 February 2014 (UTC)

Axl reworked and shortened the first paragraph and 3 endpoints for your review. Ian Furst (talk) 17:51, 24 February 2014 (UTC)

I have access to a copy of Miller's Anesthesia now. I reluctantly accept that the text places amnesia in a prominent position—perhaps even more so than hypnosis, analgesia or muscle relaxation. I need to do some more reading, but I have not forgotten about this article. Axl ¤ [Talk] 01:11, 28 February 2014 (UTC)
no rush. This article is a marathon for me, not a sprint. Ian Furst (talk) 02:53, 28 February 2014 (UTC)

Lead section[edit]

In the UK, "Anaesthesia" is also the name of the medical specialty known elsewhere as "Anesthesiology". I wonder if this is worth mentioning? Axl ¤ [Talk] 23:46, 19 March 2014 (UTC)

I can add the info under the society section. We call them the same in Canada. The article was previously a hodge-podge of debate about who gives anesthetics so, if you're OK with it, I'd prefer to keep discussion of such issues like this isolated to that section. Ian Furst (talk) 03:27, 20 March 2014 (UTC)
Hmm, okay. I edited the disambiguation page to add "Anesthesiology". However I have just discovered that "Anesthesiology" redirects to this article! I shall create a stub article for "Anesthesiology". Axl ¤ [Talk] 12:53, 20 March 2014 (UTC)
Didn't know about the redirect - thanks. Not surprised though - the article was previously a mix about anesethesia itself and the specialties. Ian Furst (talk) 13:13, 20 March 2014 (UTC)

Article claims fight or flight response leads to shock[edit]

The current version of the article claims that the fight or flight response leads to circulatory shock. This seems counter-intuitive, since the fight or flight response increases blood pressure, while circulatory shock is a result of low blood pressure. This statement needs to have a reliable reference, and probably also an explanation to justify how the fight or flight response results in shock.

I think it would make sense if it were clarified to refer to only cases of excessive fight or flight response, causing extreme sinus tachycardia, resulting in decreased stroke volume leading to reduced cardiac output. However, the way it's written right now, it sounds like the article is claiming that people have a dangerous drop in blood pressure whenever they are exposed to an alarming or stressful situation, but that's the opposite of what usually happens. -NorsemanII (talk) 00:10, 4 May 2014 (UTC)

NorsemanII Good point, let me look for the specific reference. I don't think the reference is to shock during the procedure but that which results days later due to tissue damage. My understanding (and I will look for the specific mechanism) is that extremes of blood pressure, pulse and vascular shunting lead to local vasoconstriction, thrombosis, regional malperfusion, release of superoxide radicals, and direct cellular damage which, in turn, leads to cellular injury, organ dysfunction and death. Harvey Cushings observations, where that morbidity (with hernia operations) was decrease in the post-op period, not the perioperative period. Let me find details and will repost. Ian Furst (talk) 12:55, 4 May 2014 (UTC)
NorsemanII Here is the reference [2] Shock is the correct term. We could change the flight or flight response to extremes of blood pressure but I think it's less understandable for the layperson. Thoughts? Ian Furst (talk) 13:17, 4 May 2014 (UTC)
The reference (Miller's Anesthesia, 7th edition, pages 29–30) does not mention the "fight-or-flight response". It is reasonable to equate "stress response" with "fight-or-flight response", but this is only mentioned in the last paragraph where the significance of catecholamine release is described. I do not think that it reasonable to equate "stress" with "fight-or-flight response". "Stress" is a rather more generic term.
"Shock" is mentioned only once: "Accurate anesthetic records were maintained during Cushing's cases and confirmed his opinion that shock could be prevented by careful attention to avoiding the stresses associated with surgery." I certainly do not think that "stresses" is used here to mean only "fight-or-flight response". Nor am I convinced that Harvey Cushing's definition of the word "shock" in the early 20th century is synonymous with the modern definition of "circulatory shock". Axl ¤ [Talk] 14:46, 4 May 2014 (UTC)
I think the point that needs to be made is that blunting of autonomic reflexes (e.g. extremes of blood pressure and pulse that can occur with surgery) lowers post-op morbidity, and is an important part of modern anesthesia. I think it's helpful to link to fight or flight response so people can understand why the body responds with increase heart rate/BP during surgery. I'm relatively indifferent as to whether we tie the cause of the increased post-op morbidity to shock or not. Let me read some more or email the author. Ian Furst (talk) 15:27, 4 May 2014 (UTC)

NorsemanII Axl, like everything else with this article the answer doesn't seem to be so clear cut. There is evidence that blunting the response prevent perioperative MI's. Second, it decreases levels of catabolic hormones which are thought to prolong recovery (nothing about morbidity). Here are two quotes, "Studies have demonstrated that perioperative β-adrenergic blockade reduces the risk for perioperative myocardial infarction in patients at risk for this complication.":30 "It was learned that during major surgery, patients anesthetized with traditional vapor anesthetics, with or without opioids, displayed increased levels of catabolic hormones postoperatively" ... "Various methods of preventing postoperative catabolism have been under investigation for several years. The resulting catabolic state is thought by some to delay recovery..":30 Let me keep looking to see if it's tied to shock. BTW, currently the article is titled Shock (circulatory) but it describes all types of shock. Maybe we should rename to Shock (physiologic) Ian Furst (talk) 22:46, 4 May 2014 (UTC)

I think I found the relavent section on it. It relates to the catabolic hormones which they believe increases mortality but no-one is sure why. Here is the relavent text, "Anesthetic techniques or drugs that minimize the stress response may reduce morbidity and mortality in a variety of circumstances." and "Many different hormonal changes induced by surgery have been described. However, the concomitant neural, cellular, immune, and biochemical changes have been less well defined, and little is understood or proven with regard to how modifying hormonal responses alters outcome.213 Additional studies are necessary for complete elucidation of the relationship between control of surgically induced hormonal responses and outcome." :787 Ian Furst (talk) 22:54, 4 May 2014 (UTC)
proposed change in the lead to, " surgical stimulation leading to a heart attack and production of catabolic hormones.:30 Ian Furst (talk) 23:02, 4 May 2014 (UTC)
None of the quotations that you use here describe "shock".
"BTW, currently the article is titled Shock (circulatory) but it describes all types of shock." Exactly how are you defining "shock"? Axl ¤ [Talk] 23:03, 4 May 2014 (UTC)
I have not described "shock" in any of the quotes, because I think it should be removed from the lead. Based on my reading, I believe the physiologic state created by the extremes of BP/pulse are similiar to shock (or in the case of periop MI, caused by cardiogenic shock secondarily) but I can't find anything that links to two. Therefore, I think it should be removed and replaced with a more percise description of what is believed to be occuring.
The definition of shock that I found useful is, "a multifactorial syndrome resulting in inadequate tissue perfusion and cellular oxygenation affecting multiple organ systems."[3] the point being that even if hypoperfusion and tissue ischemia are the triggers for shock, there are only a small part of the physiologic cascade that results. Ian Furst (talk) 23:13, 4 May 2014 (UTC)
I see that the definition you are using describes "inadequate tissue perfusion". In what way is the definition different from "circulatory shock"? Axl ¤ [Talk] 23:21, 4 May 2014 (UTC)
I'm not sure what you're referring to. Are you talking about whether the definition should be included in the lead of this article or whether the title Shock (circulatory) might be changed? With respect to the latter, I think the title leads one to think of hypovolemic or hemorragic shock rather than the shock state. Even though the definition includes tissue perfusion, the more complete explaination from the pathophys section better describes it, "Whereas hypoperfusion and cellular ischemia were previously thought to be sufficient to cause shock, they are now recognized as being solely the initiating triggers for a complex physiologic cascade. Cellular hypoxia predisposes tissues to "reperfusion injury" leading to local vasoconstriction, thrombosis, regional malperfusion, release of superoxide radicals, and direct cellular damage. Subsequent activation of neutrophils and release of proinflammatory cytokines such as tumor necrosis factor (TNF), interleukin-1 (IL-1), and platelet activating factor result in cellular injury, organ dysfunction and failure, and frequently death." Ian Furst (talk) 23:58, 4 May 2014 (UTC)
"I think the title leads one to think of hypovolemic or hemorragic shock rather than the shock state." With respect, that interpretation is incorrect. Here are just a few sources that mention circulatory shock—where it is not restricted to hypovolaemic shock: [4], [5], [6]. Tintinalli's Emergency Medicine defines shock: "Shock is circulatory insufficiency that creates an imbalance between tissue oxygen supply (delivery) and oxygen demand (consumption)." Shock is implicitly circulatory, which is why "circulatory" is often dropped from the phrase. Axl ¤ [Talk] 00:41, 5 May 2014 (UTC)
You'll notice I didn't say that circulatory shock is restricted to hypovolemic shock only that, in my opinion, I believe that the title leads one to think of shock as a disorder of circulation alone. From your sources, "Importantly, although the focus of this review is circulatory shock, it must be appreciated that inflammatory mediators and oxidative stress from circulatory shock and reperfusion or due to other factors (for example, sepsis) can also directly cause tissue injury." Regardless, my opinion is that the article would be better titled Shock (physiologic) which would take into account the complexity of the disorder but I acknowledge that the term circulatory shock is also used and the title works. Just a suggestion. Ian Furst (talk) 01:24, 5 May 2014 (UTC)
"I believe that the title leads one to think of shock as a disorder of circulation alone." No doubt you will be writing to the New England Journal, etc., to inform them of this potential confusion.
In Wikipedia, we have to reflect the sources. The medical literature most commonly uses the unqualified word "shock". However "Shock" has many other meanings. The second most common term used in the medical literature is "circulatory shock". PubMed has 2,140 entries for "circulatory shock". There are only five entries for "physiologic shock" and eight entries for "physiological shock".
Hence Wikipedia's title "Shock (circulatory)" is appropriate—more so than "Shock (physiologic)". Axl ¤ [Talk] 09:52, 7 May 2014 (UTC)

Got it Axl Ian Furst (talk) 11:39, 7 May 2014 (UTC)

Your proposed test is: "A general anesthetic will cause a person to sleep but the body can still mount a fight-or-flight (stress) response to surgical stimulation leading to a heart attack and catabolic hormones."? While this is supported by the reference, I don't see why this should be in the lead section. Axl ¤ [Talk] 18:07, 11 May 2014 (UTC)
I'm not opposed to it being removed. Ian Furst (talk) 19:20, 11 May 2014 (UTC)
Okay, thanks. I have deleted the sentence from the lead section. Harvey Cushing's finding is described in the "General Anesthesia" section, which is fine. Axl ¤ [Talk] 20:46, 11 May 2014 (UTC)
Should we also remove the sentence abou the muscles contracting making surgery impossible? I don't think the paragraph flows well with it there. Ian Furst (talk) 21:01, 11 May 2014 (UTC)