Intraosseous Versus Intravenous Infusion of Hydroxocobalamin for the Treatment Of Acute Severe Cyanide Toxicity in a Swine Model
ARMY INST OF SURGICAL RESEARCH FORT SAM HOUSTON TX
Pagination or Media Count:
Objectives Easily administrated cyanide antidotes are needed for first responders, military troops, and emergency department staff after cyanide exposure in mass casualty incidents or due to smoke inhalation during fires involving many victims. Hydroxocobalamin has proven to be an effective antidote, but cannot be given intramuscularly because the volume of diluent needed is too large. Thus, intraosseous IO infusion may be an alternative, as it is simple and has been recommended for the administration of other resuscitation drugs. The primary objective of this study was to compare the efficacy of IO delivery of hydroxocobalamin to intravenous IV injection for the management of acute cyanide toxicity in a well-described porcine model. Methods Twenty-four swine 45 to 55 kg were anesthetized, intubated, and instrumented with continuous mean arterial pressure MAP and cardiac output monitoring. Cyanide was continuously infused until severe hypotension 50 of baseline MAP, followed by IO or IV hydroxocobalamin treatment. Animals were randomly assigned to receive IV 150 mgkg or IO 150 mgkg hydroxocobalamin and monitored for 60 minutes after start of antidotal infusion. The primary outcome measure was the change in MAP after antidotal treatment from onset of hypotension time zero to 60 minutes. A sample size of 12 animals per group was determined by group size analysis based on power of 80 to detect a one standard deviation of the mean MAP between the groups with an alpha of 0.05. Whole blood cyanide, lactate, pH, nitrotyrosine nitric oxide marker levels, cerebral and renal near infrared spectrometry NIRS oxygenation, and inflammatory markers were also measured. Repeated-measures analysis of variance was used to determine statistically significant changes between groups over time. Results At baseline and at the point of hypotension, physiologic parameters were similar between groups.
- Medicine and Medical Research