Hemodynamics after intraosseous administration of hydroxocobalamin or normal saline in a goat model

Study Objective: Hydroxocobalamin may be lifesaving in cyanide (CN) poisoning, but personal protective equipment (PPE) wear, rescue, and decontamination may delay intravenous administration. Intraosseous (IO) lines may be rapidly placed even when wearing PPE. We assessed the hemodynamics of hydroxocobalamin (OHCo) and normal saline (NS) by the IO route. Methods: Twelve anesthetized Spanish goats underwent arterial line catheterization. Operators in PPE placed IO lines. After placement confirmation by fluoroscopy, animals randomly received hydroxocobalamin 75 mg/kg (3 mL/kg) (n = 6) or normal saline (NS) 3 mL/kg (n = 6) IO over approximately 7.5 minutes. Blood pressures and heart rates were monitored for 240 minutes after infusion initiation. Results: In the OHCo group, mean systolic and diastolic pressures peaked at 120 minutes, with mean increases of 14% and 17%, respectively, relative to infusion start, returning to near preinfusion values at 240 minutes. Heart rate changes were virtually nil. In the NS group, mean systolic pressures peaked at 60 minutes, with a mean increase of 36%, whereas diastolic pressures peaked at about 110 minutes, increasing 42%, returning to near preinfusion values at 240 minutes. Heart rate changes were minimal. Conclusion: Hemodynamic effects of OHCo given by the IO route in non-CN-poisoned goats are mild and well tolerated. Increases in mean blood pressure at peak after baseline were greater in the NS group, but the mean values over time were not significantly different from those observed in the OHCo group. Hemodynamic effects would likely differ somewhat in a CN-poisoned goat. Intraosseous OHCo administration warrants additional investigation.