Abstract
A Localizing Circumferential Compression Device Increases Survival After Coral Snake Envenomation to the Torso of an Animal Model
Eastern coral snake (Micrurus fulvius) envenomations require immediate transfer to a care facility for supportive care and, when available and indicated, treatment with antivenom. A delay in care can precipitate worsening effects of the toxin, which include respiratory depression and paralysis. Cutaneous manifestations do not indicate severity of disease. Though a circumferential compression device might delay the onset of symptoms in an extremity, it is difficult to apply compression to a torso bite. The first author of this paper patented a compression device for use on the torso and tested it in this study.
In this small, unblinded, controlled trial on pigs the authors compared 8-hour survival between 6 pigs to which the device was applied and 3 controls that received no form of compression. Pigs were matched by age and weight. Each pig was injected with 10 mg of M. fulvius venom and compression was applied 1 minute after injection in the test group. The compression device consisted of a molded, rigid loop that was used to encircle the bite site. A strap was then secured around the torso and tightened to increase the pressure on the skin and decrease blood flow from the bite.
A statistically significant delay in time to death was appreciated in the compression group with 5 of the 6 pigs living to the 8-hour end point while none of the control group survived to 8 hours. The single treated pig that died before 8 hours was noted to have a misapplication of the compression device during the first 10 minutes. This finding highlights one of the major limitations to this promising adjunct for the treatment of torso envenomations. In this study, the device was applied after 1 minute, which is unlikely to occur under normal conditions, and may negate the utility of this device.
If an effective means of delaying coral snake venom absorption and circulation can be developed, this might provide care providers with additional time to locate and obtain an appropriate antivenom to treat victims. Currently no commercial antivenom for Micrurus bites exists in the United States.
(J Emerg Med. 2010;17:1–3) JB Hack, JM Deguzman, KL Brewer, et al.
Prepared by Anil Menon, MD, UTMB/NASA Aerospace Medicine Fellow, Galveston, TX, USA