Intraarterial vs intravenous administration of antivenin for the treatment of Crotalidae atrox envenomation: a pilot study.
OBJECTIVE
Standard therapy for significant snake envenomation includes antivenin. i.v. administration is currently the only recommended route. Intraarterial (i.a.) administration has potential advantages over i.v. that could improve outcome. To study this, the authors compared i.v. and i.a. antivenin administrations for the treatment of experimental snake envenomations.


METHODS
14 adult female swine were anesthetized and prepared with femoral artery and ear vein catheters, and baseline hoof, forearm, and thigh circumference and volume displacement measurements were taken. Crotalidae atrox venom was injected into the subcutaneous tissue of the hoof. The doses of venom were 4.75, 9.50, 19.00, 37.90, 47.30, 56.90, and 66.40 mg. Immediately following injection of venom, polyvalent antivenin (Crotalidae) (0.285 mg/10 mL saline) was infused over 30 minutes into the femoral artery (i.a. group) or ear vein (i.v. group). As a control, 10 mL of saline was infused into the ear vein (i.a. group) or femoral artery (i.v. group). Measurements were recorded up to 48 hours. Linear mixed-effect regression models were used for each measurement and to compare the i.a. and i.v. groups.


RESULTS
Venom dose and time after administrations were associated with increased circumferences and increased volumes (p < 0.05). i.v. administration was associated with larger hoof (1.26 cm) and forearm (0.42 cm) sizes and volume displacement (21.71 mL) when compared with i.a. administration ( p < 0.05).


CONCLUSIONS
i.a. antivenin results in a modest but significant decrease in tissue edema when compared with i.v..
Bania
T C
TC
College of Physicians and Surgeons at the Department of Emergency Medicine, St. Luke's-Roosevelt Hospital Center, Columbia University, New York, NY 10019, USA. toxtod@aol.com
Bernstein
S L
SL
Baron
B J
BJ
Rabinowitz
D
D
D000818:Animals; D000997:Antivenins / Q000008:administration & dosage*; D003435:Crotalid Venoms; D005069:Evaluation Studies as Topic; D005260:Female; D007261:Infusions, Intra-Arterial; D007262:Infusions, Intravenous; D010865:Pilot Projects; D012909:Snake Bites / Q000628:therapy*; D013552:Swine
D000997:Antivenins; D003435:Crotalid Venoms