Written by Jacob Altholz
Spoon Feed
In this letter to the editor and reply, the use of antivenom in crotalid envenomations is debated and clarified.
Crotalid controversy – why might crotalid antivenom not decrease length of stay?
The original article (which we covered here) was a retrospective review of pediatric crotalid envenomations in two institutions with disparate practice patterns, one using antivenom much more often than the other.1 The results found no association of antivenom with a difference in hospital length of stay (LOS) or surgery.
A subsequent letter to the editor by Drs. Bonney and Greene raised some concerns. First, they question surgery as a primary outcome, since antivenom is the treatment for compartment syndrome related to envenomation.2,3 They also argue that hospital LOS is influenced by a number of extraneous factors and is a less clinically important outcome than pain control (especially longer-term outpatient opioids) and time to full recovery.
The study authors’ reply notes that each of these hospitals has a huge catchment area, making long-term follow-up on pain control and time to functional recovery extremely difficult. They also took issue with the statement, “The investigators essentially compared untreated to undertreated patients.” At LeBonheur, the median antivenom dose was one vial, whereas at Vanderbilt the median dose was 8 vials, which is consistent with toxicology guidelines. The study authors clarify they are not suggesting that antivenom be withheld in appropriate patients, such as progression of disease, compartment syndrome, bites on the hand, or other severe manifestations of envenomation.
How does this change my practice?
The letter raises several good points:
- antivenom should almost always be used instead of surgery
- more patient-centered outcomes would be ideal
- antibiotics for envenomation should be minimized
- limb elevation is crucial.
And their concern about readers simply ditching antivenom is valid.
The Vanderbilt reply agrees, stating, “We are not suggesting the standard of care be changed to withhold antivenom. When indicated after careful evaluation of the patient and possible observation, treatment should be rendered.” However, the authors point out the findings of their study demonstrate the “need for further study regarding the best approaches for Agkistrodon envenomation in children.” I think we can all agree on that.
I wonder if populations with largely Agkistrodon (copperhead) bites may find it more difficult to detect clinically important differences related to crotalid antivenom use.
Sources
Letter to the editor re: Comparing the Use of Crotaline-Polyvalent Immune Fab (Ovine) Versus Observation in Children. Pediatr Emerg Care. 2024;40(11):e270-e276. Pediatr Emerg Care. 2025 Mar 20. doi: 10.1097/PEC.0000000000003373. Epub ahead of print. PMID: 40108879
Reply: Comparing the Use of Crotaline-Polyvalent Immune Fab (Ovine) Versus Observation in Children. Pediatr Emerg Care. 2025 Mar 20. doi: 10.1097/PEC.0000000000003380. Epub ahead of print. PMID: 40111158
Works Cited
- Comparing the Use of Crotaline-Polyvalent Immune Fab (Ovine) Versus Observation in Children. Pediatr Emerg Care. 2024 Nov 1;40(11):e270-e276. doi:10.1097/PEC.0000000000003245. Epub 2024 Jul 23. PMID: 39043166
- Compartment Syndrome after Crotalid Envenomation in the United States: A Review of the North American Snakebite Registry from 2013 to 2021 on Behalf of the ToxIC Snakebite Study Group. Wilderness Environ Med. 2023 Sep;34(3):322-327. doi: 10.1016/j.wem.2023.05.007. Epub 2023 Jul 18. PMID: 37474357
- Upper Extremity Crotalid Envenomation: A Review of Incidence and Recent Trends in Management of Snakebites. J Hand Surg Am. 2023 Dec;48(12):1277.e1-1277.e6. doi: 10.1016/j.jhsa.2022.04.016. Epub 2022 Jun 17. PMID: 35725686
I would emphasize the possible effect of copperheads. This rationale does not necessarily applied to all crotalids (rattlesnakes). There’s been some good data to say that maybe copperheads don’t need anti-Venom. For folks that live in areas without copperheads, or if you know that the snake was another rattler, these articles about the efficacy are pretty irrelevant. Don’t let the title make you think that the rationale applies to all rattlesnakes.