intraOsseous Devices Lady Minto Emergency Rounds November 29, 2016 Prepared by Shane Barclay

Types of Devices Pediatric manual (‘bone marrow’) needles IO Drill Sternal intraosseous device

Pediatric Manual insertion IO needle

EZ - IO drill

Sternal intraosseous

Average time of insertion of IO devices Various studies have been done, but on average: Time Success rate Humeral 7 minutes 40% Tibial 4 minutes 80-100% Sternal 2 minutes 95-100%

Back to Gross anatomy – types of bone marrow In children most bone marrow is ‘red’ (hematopoetic) versus ‘white’ marrow (fat). In adults the only ‘red’ marrow tends to be in vertebrae, sternum, ribs, skull and proximal metaphysis of the humeri and femurs.

Why is type of bone marrow important? (Prehospital Emergency Care – October 2014. B Rubel et al) Even in children receiving IO infusions through the tibia, there are documented cases of fat emboli, likely contributing to deaths. This has been confirmed in animal studies. In adults tibial insertion would at least theoretically be associated with higher fat emboli rates due to the fatty nature of tibial marrow.

Pharmacokinetics of IO and Central venous medication administration (Resuscitation 82 (2012) 107-112, S. Hoskins et al) This study compared pharmacokinetics of dye tracers in tibial versus sternal administration and then sternal versus central venous IV. Mean time to maximum concentration was 107 seconds for tibial and 53 seconds for sternal. Mean time to maximum concentration in Central venous versus sternal was not statistically significant.

Pharmacokinetics of IO and Central venous medication administration (Resuscitation 82 (2012) 107-112, S. Hoskins et al) Conclusion: “Based on the present data, we recommend that sternal IO route be considered as the first choice of drug delivery during CPR when IV access has not been established and that the tibial IO route is also justified as a second choice”

Epinephrine Delivery in CPR (AANA Journal, August 2012, S6-10, J. Burger et al) The serum half life of epinephrine is about 120 seconds. The above study showed it takes on average 156 seconds for a tibial IO infusion to deliver only 1/5 of the epinephrine concentration that an IV would provide. (And this study was done on a porcine model which have obviously shorter legs than humans!)

Epinephrine Delivery in CPR (AANA Journal, August 2012, S6-10, J. Burger et al) “The IV administration of 1 mg epinephrine resulted in a serum concentration 5.87 and 2.86 times greater than for the tibial and sternal routes of administration respectively.” The mean time to maximal concentration of epinephrine was significantly different between tibial and sternal routes but were not different compared to sternal and IV routes.

Epinephrine Delivery in CPR

Epinephrine Delivery in CPR (AANA Journal, August 2012, S6-10, J. Burger et al) Conclusions: “The findings of this study suggest that higher doses of epinephrine may be needed when administered via the IO route to patients in cardiac arrest” Note: the authors did not suggest a specific dosage adjustment.

IO infusion rates under high pressure (J Trauma Acute Care Surg vol 78, 2015 J Pasley et al) The mean flow rates under pressure of crystalloid infused per minute at each site was Tibia 31 mL/min Humerus 57 mL/min Sternum 94 mL/min (Note: other studies have shown much higher flow rates ie 3x, under pressure, but with similar differences based on IO site)

IO infusion rates under high pressure (J Trauma Acute Care Surg vol 78, 2015 J Pasley et al) Conclusions: “In our fresh human cadaver model, the sternal IO site provided the highest flow rates compared with the humeral and tibial insertion sites” “The sternal site was also associated with a 100% success rate for initial placement” “Based on this analysis, the sternal site seems to have the optimal flow rate for most adult resuscitation”

Questions ?