Comparing the Use of Crotaline-Polyvalent Immune Fab (Ovine) Versus Observation in Children.

Objectives: In the United States, studies are inconclusive regarding the indications for polyvalent antivenom administration for crotaline envenomation. We compared polyvalent antivenom administration versus observation used at 2 separate institutions. We hypothesized that deferring antivenom leads to increased hospital length of stay and surgical interventions.

Methods: Retrospective chart review of children who presented to Le Bonheur Children's Hospital (LBCH) in Memphis, Tennessee, and Monroe Carell Jr Children's Hospital at Vanderbilt (MCJCHV) in Nashville, Tennessee, from 2009 to 2021. Patient demographics, treatment utilization, bite location, and outcomes from both sites were statistically examined.

Results: A total of 183 patients met the inclusion criteria (123 at LBCH, 60 at MCJCHV). At LBCH, mean age was 9.2 years, 54% were male, and 79% of known snakes identified as copperheads. At MCJCHV, mean age was 8.9 years, 65% were male, and 88% of known snakes identified as copperheads. The most commonly envenomated areas for both sites were the foot (42%), hand (27%), and ankle (26%). Patients at LBCH were managed with antivenom only 25% of the time, whereas 75% were observed; 82% of MCJCHV patients were managed with antivenom (P < 0.001). There were no significant differences in length of stay (mean, 1.5 days at LBCH and 1.8 days at MCJCHV; P = 0.136) or surgical intervention (3.3% of LBCH encounters, 5.0% of MCJCHV encounters; P = 0.685). Secondary outcomes aside from coagulopathy and admission location (intensive care unit vs floor) were also not significant.

Conclusions: The use of antivenom did not impact hospital length of stay or surgical interventions. Our results should be interpreted cautiously as our study reflects regional experiences with snake species in the Southeast United States and not North America as a whole. Other institutional differences in management and smaller n at MCJCHV may have contributed to different outcomes. Further study is needed to determine intermediate and long-term effects of deferring antivenom use.