Neurotoxicity with persistent unilateral ophthalmoplegia from envenoming by a wild inland taipan (Oxyuranus microlepidotus, Elapidae) in remote outback South Australia

Envenoming by a captive inland taipan, Oxyuranus microlepidotus (McCoy, 1879), Elapidae. A case report, observations on clinical efficacy of expired antivenom and review of O. microlepidotus envenoming

The clinical evolution and management of a 22-yr-old male envenomed by a captive female inland taipan, Oxyuranus microlepidotus (McCoy, 1879), Elapidae, at a public educational reptile exhibit (Florida, USA) is reported. The patient was bitten (quick 'bite and release') in the right hand between digits #3 and 4 while performing captive maintenance. The victim did not attempt any first aid, but urgently presented to the local hospital within 25 mins post-bite. The patient had an unremarkable medical/surgical history including no previous envenoming/treatment with antivenom. Within approximately 5 mins post-bite he reported experiencing transient loss of consciousness/syncope, altered sensorium, nausea, dull headache, weakness, and "severe" bite site pain. Laboratory investigations revealed profound defibrinating coagulopathy including thrombocytopenia; there was only mildly elevated creatine kinase and renal function remained within normal limits. The patient's clinical evolution included cranial nerve palsies manifested as dysconjugate gaze, persistent, but minor, bite site bleeding, asthenia and reported myalgia as well as prolonged intense bite site pain. He was successfully and uneventfully treated with four vials of Australian polyvalent antivenom and one vial of taipan monovalent; all were expired products with expiration dates ranging from one month to 38 years. Effective antivenom therapy might have been achieved with only 2, possibly 3 vials; however, concerns about reduced efficacy of the long-expired antivenom (4/5 vials were expired 18-38 years) and persistent bite site bleeding/pain contributed to the provision of the additional vials. The patient recovered sufficiently for discharge in 48 h; there were no sequelae. There have been approximately 12 formally documented cases of O. microlepidotus envenoming and selected, detailed examples of these are briefly considered and compared with the clinical evolution of our patient; patient-centred recommendations for management of Oxyuranus spp. envenoming are discussed. The need for advanced preparedness and an action plan for any institution/collection that contains non-native, medically significant venomous species is emphasised, and a general recommended approach is outlined.

Retrieval medicine and pre-hospital care in remote Australia

Retrieval medicine and pre-hospital care in remote Australia are challenging, requiring competencies in major trauma, high-risk obstetrics, critical care in adults and children, severe mental health-related agitation and envenomation. They keep a city-based retrieval and pre-hospital care doctor on their toes. Cultural fluencies to enhance care for Aboriginal and remote communities are critical during the long hours taken for the patient journey from the accident scene or clinic to definitive care.