Venom Detection

• The Snake Venom Detection Kit (SVDK) is not kept in the Emergency Department, but in Haematology
• ED staff collect the specimens and send to Haematology
• For advice on the management of snake bites contact Poisons Information: 131126 or refer to the Toxicology Handbook 

Background

• Venom is most likely to be detected in a swab from the bite site
• Urine may be tested in patients who show evidence of envenomation when the bite site swab was inconclusive
• As a last resort venom stained clothing may be tested
• Blood should not be sent for venom detection

Indications

• The SVDK is not used to determine if the patient has been envenomed
• Evidence of envenomation is based on history, physical examination and the results of laboratory tests
• If envenomation is confirmed, the (SVDK  is used by the laboratory to determine the correct monovalent antivenom to be used for treatment

Preparation 

Staff

• Specimen collection is to be carried out by an ED Doctor
• Specimens are then sent to Haematology for testing

Equipment

Procedure 

Ensure use of personal protective equipment

Bite site specimen (preferred)

• Moisten the buffered swab with 0.9% saline solution
• Do not remove the pressure immobilisation bandage
• Separate the bandage to create a small window to expose the bite site
• Swab the bite site thoroughly (the puncture marks can be gently squeezed)
• Send the labelled swab immediately to Haematology with “snake venom detection” written on request form
• Do not delay while other specimens are collected

Urine specimen (alternative specimen if envenomation is clinically likely, but bite site specimen negative or inconclusive)

• Collect a fresh urine sample in a yellow-top urine collection jar
• Send the labelled sample to the Haematology lab with “snake venom detection” written on request form

Clothing specimen (alternative specimen)

• Venom stained clothing or bandage can be tested
• Cut a small piece of the affected cloth – about 1cm square
• Place cloth in a dry yellow-top urine collection jar
• Send the labelled specimen to Haematology with “snake venom detection” written on request form