Case 28 – Envenomations

Case # 28 – Envenomation
Author: Jason Murphy, MD
Peer Reviewer: Jenny Lu, MD

A mother brings her 15 year old son to your ED. She states that he was out in the national park near their house when he was bitten by what he claims was a rattlesnake. The mother confirms that she also saw the rattlesnake. He was bitten on both his right arm and left leg, and he is writhing in pain. His past medical history is unremarkable.

Vitals: Temp: 98.2, HR: 115, RR: 25, BP: 120/75, O2 Sat: 100% on RA.

On exam, your worst fears are confirmed when you note his right arm and left leg are swollen, covered in black necrotic eschar, and there is serosanguanous drainage from both sites. You also note blood in his oral and nasal mucosa.

What are the two major categories of venomous snakes in the United States? How can you differentiate them?
Does every bite by a venomous snake result in an envenomation? What findings would you expect on physical exam to suggest envenomation?
What labs do you want? What are you looking for?
What is the recommended treatment for this envenomation?
As he is being wheeled up to the ICU, his mother asks you if there is anything she could have done differently before they went to the hospital (tourniquets, suction devices, immobilizations) that could have helped her son. What does the evidence say?
Is there any role for antibiotics?


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Hall EL. Role of surgical intervention in the management of crotaline snake envenomation. Ann Emerg Med. 2001 Feb;37(2):175-80.

Lavonas EJ, Ruha AM, Banner W, et al. Unified treatment algorithm for the management of crotaline snakebite in the United States: results of an evidence-informed consensus workshop. BMC Emerg Med. 2011 Feb 3;11:2.

LoVecchio F, Klemens J, Welch S, et al. Antibiotics after rattlesnake envenomation. J Emerg Med. 2002 Nov;23(4):327-8.

McKinney PE. Out-of-hospital and interhospital management of crotaline snakebite. Ann Emerg Med. 2001 Feb;37(2):168-74.

Shaw BA, Hosalkar HS. Rattlesnake bites in children: antivenin treatment and surgical indications. J Bone Joint Surg Am. 2002 Sep;84-A(9):1624-9.

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