Cobra Envenomation Workup
- Author: Robert L Norris, MD; Chief Editor: Joe Alcock, MD, MS more...
Laboratory studies offer no diagnostic benefit for snake envenomation. Baseline labs (eg, complete blood count [CBC], electrolyte tests, renal function studies, coagulopathy panels) may be reasonable in severe bites or if the patient has significant underlying medical problems. Coagulopathy is not an expected feature of bites by most cobras, though prolonged bleeding and failure of clot retraction have been reported following bites by African spitting cobras and anticoagulant proteins have been identified in the venom of the African ringhals (Hemachatus haemachatus).
Arterial blood gas (ABG) determinations may be helpful if the patient's respiratory status is questionable.
In some regions of the world, researchers are developing immunologic tools, such as enzyme-linked immunosorbent assays (ELISAs), to aid in species identification and possibly in severity grading.
A chest radiograph benefits patients who have severe envenomations, require intubation, or show evidence of cardiorespiratory failure.
An electrocardiogram (ECG) should be obtained if the victim complains of chest pain or if there is evidence of dysrhythmia.
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