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Comparative Study
. 2025 Dec 20;27(1):167-176.
doi: 10.5811/westjem.45709.

Retrospective Comparison of Empiric Antivenom vs. Expectant Treatment for Eastern Coral Snakebites

Reeves Simmons  1 , Chiemela Ubani  1 , Gerard Garvan  2 , Molly Stott  1 , Dawn Sollee  1   3 , Jay Schauben  1   3 , Alexandra Derr  3 , Colleen Cowdery  3 , Lindsay Schaack Rothstein  1 , Hayley Gartner  1 , Ashton Federico  3 , Sophia Sheikh  1   3
Affiliations
Comparative Study

Retrospective Comparison of Empiric Antivenom vs. Expectant Treatment for Eastern Coral Snakebites

Reeves Simmons et al. West J Emerg Med. .

Abstract

Introduction: The coral snake is the only native elapid in North America. Their venom contains potent neurotoxins. Historically, all confirmed/presumed bites were treated with antivenom whether or not symptoms were present. Production of antivenom ceased in 2003. The resultant national shortage prompted clinicians to investigate alternative treatment strategies such as a wait-and-see approach where antivenom is held until signs of systemic toxicity manifest. Now that production has resumed there is limited research available comparing these two treatment paradigms, empiric administration vs the wait-and-see approach. Our objective in this study was to compare outcomes of the two treatment paradigms to determine whether one is associated with better patient outcomes.

Methods: This was a retrospective analysis of coral snakebite cases reported to the Florida Poison Information Center Network from January 1, 1998-December 31, 2021. We collected demographic, clinical, and outcome variables. Patients were stratified into two groups, empiric antivenom administration vs the wait-and-see approach in patients who were asymptomatic in terms of systemic symptoms at the time of initial presentation to the emergency department. We used multivariable logistic regression models, controlling for whether the bite occurred during the North American Coral Snake Antivenin (NACSA) shortage period (yes/no), age, sex, and whether systemic effects developed (yes/no), to determine differences between study groups in the incidence of the main outcomes: intensive care unit (ICU) admission; intubation; and death, as well as ICU and hospital length of stay.

Results: We analyzed 301 cases: 171 (56.8%) empiric; and 130 (43.2%) wait-and-see. Patients in the empiric treatment group had approximately three times higher likelihood of ICU admission (empiric 121 [75.2%] and wait-and-see 71 [56.8%]), odds ratio [OR} 3.047, P = .05). There was no difference in the incidence of intubation (empiric 2 [1.2%] and wait-and-see 1 [<1%]), OR 2.486, P = .63) or in ICU length of stay (OR 0.485, P = .08). Of the patients treated with NACSA (191), adverse reactions to the antivenom occurred in 38 (19.9%) patients-35 patients in the empiric group and three in the wait-and-see group who later received antivenom. Of these 38 patients, eight (21.1%) experienced an anaphylactic reaction.

Conclusion: Empiric North American Coral Snake Antivenin administration was associated with higher ICU admissions and with a considerably higher risk of adverse reactions, which may serve to impose caution when treating empirically.

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Conflict of interest statement

Conflicts of Interest: By the WestJEM article submission agreement, all authors are required to disclose all affiliations, funding sources and financial or management relationships that could be perceived as potential sources of bias. No author has professional or financial relationships with any companies that are relevant to this study. There are no conflicts of interest or sources of funding to declare.

Figures

Figure 1
Figure 1
Patient screening and inclusion for empiric antivenom administration vs wait-and-see approach in cases of coral snake envenomation.
Figure 2
Figure 2
Demographics and snakebite characteristics for empiric antivenom administration vs wait-and-see treatment approach for coral snake exposures managed by the Florida Poison Information Center Network.
See this image and copyright information in PMC

References

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