Purpose: Fat and bone marrow embolism have been reported post IO infusion in stable subjects. The purpose of this study is to investigate the incidence and magnitude of fat and bone marrow embolism with the use of IO infusion during prolonged CPR. Methods: 31 piglets were anesthetized, mechanically ventilated, and instrumented (carotid artery, PA and IO cannulas). Following stabilization, the animals underwent hypoxic cardiac arrest followed by chest compressions with mechanical thumper and mechanical ventilation for a minimum of 45 minutes. The animals were divided into groups: A (n=5) which had no IO, group B (n=6) had IO with no infusion, and groups C (n=6), D (n=6), E (n=8) had IO with infusion of epinephrine, normal saline and sodium bicarbonate, respectively. At cessation of CPR, surviving animals were euthanized, representative lung samples were collected from upper and lower lobes of each lung, embedded in OCP and frozen immediately. Lung specimens were stained using Oil Red-O dye and observed for fat globules and bone marrow elements. The amount of emboli present was rated as a percentage in relation to lung tissue, by a pathologist blinded to the experimental groups. Buffy coat specimens were collected before and at cessation of CPR, stained with Oil Red-O dye and observed for fat globules. Results: Fat globules and bone marrow elements were seen in the prebronchial blood vessels and in intravascular areas throughout all lung fields. There was no difference in appearance or distribution of fat globules between groups Quantity varied in the different groups[(A) 45%, (B) 44%, (C) 30% (D) 23%, (E) 25%], and were less in those receiving infusions. Fat globules in the buffy coat were few and inconsistent with lung findings, Conclusion: Fat and bone marrow emboli were present in all experimental conditions. The use of the IO cannula does not increase the magnitude of embolization during CPR. Our findings suggest that emboli are likely due to traumatic effects of CPR rather than the placement of an IO cannula or use of IO access for fluid and drug administration. The decision to use the IO route should not be influenced by the risk of embolization.
|Original language||English (US)|
|Journal||Journal of Investigative Medicine|
|State||Published - Jan 1 1996|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)