Intraosseous infusion

Intraosseous infusion ("IO") is the process of injection directly into the marrow of the bone. The needle is injected through the bone's hard cortex and into the soft marrow interior. Often the antero-medial aspect of the tibia is used as it lies just under the skin and can easily be palpated and located. Anterior aspect of the femur, the superior iliac crest and the head of the humerus are other sites that can be used.

This route of fluid and medication administration is an alternate one to the preferred intravascular route when the latter can't be established in a timely manner especially during pediatric emergencies. When intravascular access cannot be obtained in pediatric emergencies, intraosseous access is usually the next approach. It can be maintained for 24–48 hours, after which another route of access should be obtained. Intraosseous access is used less frequently in adult cases due to greater difficulty penetrating denser adult bone.

Although intravascular access is still the preferred method for medication delivery in the prehospital area, advances in IO access (such as the F.A.S.T.1 and the EZ-IO system) for adults has caused many systems to re-think their preferred secondary access route. In Massachusetts, for example, IO is now a preferred administration over ET (endotracheal) drug administration. In fact the AHA no longer recommends using the ET tube for resuscitation drugs since the efficacy is unclear. Many Paramedics start an IO in a cardiac arrest patient if no vein is clearly visible. The IO is becoming more and more common in EMS systems around the world. Furthermore, any medication that can be introduced via IV can be introduced via IO. This has caused adult IO systems (most of which use a mechanical or powered adjunct to place the catheter) to become more common across the United States in the prehospital setting. Intraosseous access has roughly the same absorption rate as IV access, and (unlike ET administration) allows for fluid resuscitation as well as high-volume drugs such as sodium bicarbonate to be administered in the setting of a cardiac arrest when IV access is unavailable. Endotracheal (ET) administration allows only specific drugs that have relatively low toxicity to lung tissue, and must be restricted to relatively low volumes to prevent drowning the patient.

Effectiveness

This American Heart Association guideline cited two randomized controlled trials, one of 60 children and one of electively cannulated hematology/oncology patients. In addition, uncontrolled studies have been performed, one of which reported 72% to 87% rates of successful insertion.

History

In 1936, Tocantins and O'Neill found that when they injected 5 ml of saline into a long bone of a rabbit, only 2 ml were recovered at the distal end. They reasoned that the saline had been absorbed into the systemic circulation. Subsequent tests confirming absorption included injecting dye into the marrow cavity. Within 10 seconds, the dye reached the heart. A procedure of sternum injection was developed and subsequently used by paramedics in WWII.

External links

• B.I.G- First Automatic Intraosseous Devices by WaisMed Ltd.
  • B.I.G (Bone Injection Gun) Training material: movies and presentations
• Pyng Medical's F.A.S.T.1 Intraosseous Infusion System
  • detailed instructions
  • Technical Documents & Bibliography)
• VidaCare intraosseous infusion products
• MeSH E05.300.510.560