Rebound coagulopathy in patients with snakebite presenting with marked initial coagulopathy

Area of Science:

• Toxicology
• Emergency Medicine
• Hematology

Background:

• Pit viper envenomation frequently leads to coagulopathy, necessitating antivenom therapy.
• Limited evidence exists regarding optimal Crotalinae Polyvalent Immune Fab (FabAV) administration and follow-up duration.
• Assessing coagulopathy recurrence is crucial for managing snakebite complications.

Purpose of the Study:

• To evaluate the incidence of marked and recurrent coagulopathy after pit viper envenomation.
• To identify clinical practices that may prevent severe snakebite complications.
• To inform evidence-based guidelines for antivenom use and patient monitoring.

Main Methods:

• Retrospective review of patient records over a 3-year period.
• Inclusion criteria: symptomatic snakebite injury with international normalized ratio (INR) > 2.0.
• Exclusion criterion: patients on anticoagulant therapy.

Main Results:

• 3 out of 61 patients (4.9%) met inclusion criteria for significant coagulopathy.
• Two patients experienced asymptomatic rebound coagulopathy, detected only through laboratory follow-up.
• Repeat FabAV administration rapidly resolved rebound coagulopathy in all affected patients.

Conclusions:

• Periodic laboratory monitoring (INR, fibrinogen, platelets) is recommended for pit viper bite patients.
• Monitoring for 10-14 days post-envenomation is advised to detect asymptomatic rebound coagulopathy.
• Prompt re-administration of FabAV is effective in treating recurrent coagulopathy.