A localizing circumferential compression device increases survival after coral snake envenomation to the torso of an animal model.

BACKGROUND

Pressure immobilization bandages have been shown to delay onset of systemic toxicity after Eastern coral snake (Micrurus fulvius) envenomation to the distal extremity.

OBJECTIVES

To assess the efficacy of a novel compression device in delaying onset of systemic toxicity after truncal envenomations with Eastern coral snake (Micrurus fulvius) venom in a porcine model.

METHODS

With University approval, nine juvenile pigs (11 kg to 22 kg) were sedated, anesthetized, and intubated but not paralyzed to ensure continuous spontaneous respirations in a university animal laboratory. Each animal was injected subcutaneously with 10 mg of M. fulvius venom in a pre-selected area of the trunk. After 1 min, six animals had the application of a novel, localizing circumferential compression (LoCC) device applied to the bite site (treatment group) and three animals had no treatment (control group). The device was composed of a rigid polymer clay form molded into a hollow fusiform shape with an internal dimension of 8 × 5 × 3 cm and an elastic belt wrapped around the animal securing the device in place. Vital signs were recorded at 30-min intervals. End points included a respiratory rate below 3 breaths/min, oxygen saturation < 80%, or survival to 8 h. Survival to 8 h was analyzed using Fisher's exact test, with p < 0.05 indicating significance. Survival analysis was performed using the Mantel-Cox test to assess time to death with outcomes represented in a Kaplan-Meier Cumulative survival plot.

RESULTS

Five of the six pigs in the treatment group survived 8 h (293-480 min). None of the control pigs survived to 8 h (Fisher's exact p = 0.04), with mean time of respiratory failure 322 min (272-382 min). Survival analysis showed a significant delay in time to event in the treatment group compared to the control group (p = 0.04).

CONCLUSIONS

The LoCC device used in this study delayed the onset of systemic toxicity and significantly increased survival time after artificial truncal envenomation by Eastern coral snake venom.