Cobra envenomation: an uncommon emergency

An unusual case involving a cobra snake envenomation is presented. The patient developed transient neurological sequelae during air evacuation to a regional trauma center and required endotracheal intubation. He developed a hypersensitivity reaction to cobra antivenin which responded to diphenhydramine. The bite wound became edematous and necrotic, but responded to conservative therapy. He was discharged on the fifth hospital day and did well.     

毒蛇咬伤患者早期使用抗菌药物的对比研究

目的 探讨毒蛇咬伤患者早期是否需要预防性使用抗菌药物.方法 选取2009年4月1日-2014年11月30日该院收治的毒蛇咬伤住院患者154例,分为预防性使用抗菌药物组(A组)和未使用抗菌药物组(B组),比较两组患者脓肿、溃疡、发热、脓毒症、截肢及死亡的发生率和平均住院时间.结果 A组脓肿、溃疡、发热、脓毒症、截肢及死亡的发生率分别为2.53％、21.51％、12.66％、7.59％、0.00％和0.00％;B组分别为2.67％、21.33％、12.00％、6.67％、0.00％和0.00％,两组发生率比较差异均无统计学意义(P＞0.05).A组平均住院时间[(5.84±1.43)d]与B组[(5.91±1.64)d]比较,差异无统计学意义.结论 蛇咬伤患者在没有明确感染时不需要使用抗菌药物.     

Blindness and scalp haematoma in a child following a snakebite

BackgroundSnake envenomation is a major public health problem of the Savannah regions of West Africa. Ocular manifestations of snakebites are rare with few reports documenting blindness as a complication.ObjectiveTo highlight an unusual manifestation of snake bites and its attendant problemsMethodsA report of scalp haematoma and blindness in a 10 year old child presenting 2 weeks after a snake bite (presumably carpet viper) is a rare manifestation. Local swelling, epistaxis, bilateral proptosis, exposure keratopathy and use of traditional eye medications were associated findings. Anti-venom though administered late saved the child''s life but blindness could not be reversed.ResultsOcular ultrasonography revealed layered retrobulbar collection in the left eye, presumably due to hemorrhage. The skull x-ray showed a soft tissue swelling and aspirate from scalp swelling was bloody. Cranial Computed Tomography (CT) scan done late detected no abnormalities.ConclusionSnakebite is associated with lifelong morbidity. Ocular manifestations must be treated as emergency. This case highlights the effect of ignorance and poverty in a setting of a common medical emergency leading to blindness and reduced quality of life.     

Monocled Cobra (Naja kaouthia) Envenomations Requiring Mechanical Ventilation

BackgroundBites from nonnative snakes are uncommon, accounting for 1.1% of envenomations reported to poison centers between 2015 and 2018. Here we discuss two monocled cobra (Naja kaouthia) envenomations resulting in respiratory failure.Case ReportsA 30-year-old man and a 40-year-old man were bitten by their captive monocled cobras. At the first hospital, the first patient was mildly hypotensive, transiently bradycardic, and confused. He was intubated for respiratory distress. He was hypertensive to 211/119 mm Hg upon arrival to the second hospital. In the Emergency Department, cobra antivenom was administered. He was admitted to the medical intensive care unit (MICU) and had an additional bradycardic episode that corrected with atropine. He was extubated after 35 h. He was observed for an additional 9 h prior to going home, where he recovered without incident. The second patient developed abdominal pain, blurry vision, and dyspnea within 90 min of the bite. He was intubated at the first hospital. At the second hospital he received cobra antivenom and was admitted to the MICU. He was extubated after 9 h and discharged the following day with no further symptoms.Why Should an Emergency Physician Be Aware of This?Envenomations after N. kaouthia bites are characterized by local tissue injury and various neurotoxic effects. Nonspecific signs and symptoms are common. Hematologic toxicity and cardiovascular manifestations are uncommon. Antivenom is the specific treatment for snake envenomation, but only certain antivenoms are indicated for N. kaouthia. Cholinesterase inhibitors may reduce toxicity from postsynaptic alpha toxins by increasing acetylcholine concentrations.     

Traditional Use of Plants Against Snakebite in Indian Subcontinent: A Review of the Recent Literature

Snakebite has been a major cause of mortality across the tropical countries including Indian subcontinent. The present review deals with the enormous amount of ethnobotanical work performed in the last few years involving use of different plants against snakebite in Indian subcontinent (India, Bangladesh, Pakistan and Nepal). From a variety of literature sources the data has been compiled mentioning the plants, parts used, dosage, mode of administration, name of the ethnic communities, geographical locations etc. depending on the availability of information.     

Clinical presentation and management of an Aruban rattlesnake bite in the Netherlands

Bites by Aruban Rattlesnake (Crotalus durissus unicolor) are rare and not known to induce severe envenomations. Here, we present a case of a 57 year-old man bitten by his pet Aruban Rattlesnake (Crotalus durissus unicolor). He was admitted to hospital within 15?min. Three and a half hours later his fibrinogen concentration decreased to 0.6?g/L (normal: 2.0–4.0). Nine hours post-bite, he was treated with polyvalent snake antivenom covering Crotalus durissus. Three hours later his fibrinogen became undetectable while at that time clotting times were prolonged (PT 38.7?s (normal: 12.5–14.5) and aPTT 40?s (normal: 25–35)). His platelet count remained within normal limits. Creatine kinase (CK) concentrations reached a maximum of 1868?U/L (normal:?<200) 16?h post-bite. After a second antivenom dose, 10.5?h after the first antivenom administration, clotting times returned to normal. Fibrinogen was restored to normal within three days. He was discharged from hospital on day five. In conclusion, administration of polyvalent snake antivenom covering Crotalus durissus snakebites shows cross-neutralization and is effective in the treatment of patients bitten by Crotalus durissus unicolor.     

Australian taipan (Oxyuranus spp.) envenoming: clinical effects and potential benefits of early antivenom therapy – Australian Snakebite Project (ASP-25)

Context: Taipans (Oxyuranus spp.) are medically important venomous snakes from Australia and Papua New Guinea. The objective of this study was to describe taipan envenoming in Australian and its response to antivenom.

Methods: Confirmed taipan bites were recruited from the Australian Snakebite Project. Data were collected prospectively on all snakebites, including patient demographics, bite circumstances, clinical effects, laboratory results, complications and treatment. Blood samples were taken and analysed by venom specific immunoassay to confirm snake species and measure venom concentration pre- and post-antivenom.

Results: There were 40 confirmed taipan bites: median age 41 years (2–85 years), 34 were males and 21 were snake handlers. Systemic envenoming occurred in 33 patients with neurotoxicity (26), complete venom induced consumption coagulopathy (VICC) (16), partial VICC (15), acute kidney injury (13), myotoxicity (11) and thrombocytopenia (7). Venom allergy occurred in seven patients, three of which had no evidence of envenoming and one died. Antivenom was given to 34 patients with a median initial dose of one vial (range 1–4), and a median total dose of two vials (range 1–9). A greater total antivenom dose was associated with VICC, neurotoxicity and acute kidney injury. Early antivenom administration was associated with a decreased frequency of neurotoxicity, acute kidney injury, myotoxicity and intubation. There was a shorter median time to discharge of 51?h (19–432?h) in patients given antivenom?<4?h post-bite, compared to 175?h (27–1104?h) in those given antivenom?>4?h. Median peak venom concentration in 25 patients with systemic envenoming and a sample available was 8.4?ng/L (1–3212?ng/L). No venom was detected in post-antivenom samples, including 20 patients given one vial initially and five patients bitten by inland taipans.

Discussion: Australian taipan envenoming is characterised by neurotoxicity, myotoxicity, coagulopathy, acute kidney injury and thrombocytopenia. One vial of antivenom binds all measurable venom and early antivenom was associated with a favourable outcome.     

Investigating pressure bandaging for snakebite in a simulated setting: Bandage type,training and the effect of transport

Background: The clinical evidence base for the use of pressure bandaging in snakebite is limited. We aimed to investigate if pressure bandages (PB) generated and maintained presumptive optimal pressures in a simulated setting. Methods: A total of 96 subjects were recruited, 78 health professionals and 18 from the general public. Participants were asked to apply PB with crepe and with an elasticized bandage without instruction. A paediatric blood pressure cuff attached to a pressure transducer was used to measure the pressure generated. PB application with elasticized bandages was repeated by 36 participants (18 general public and 18 health professionals) with feedback on pressures attained, and reassessment on the sixth subsequent attempt. Pressure was also measured under correctly applied bandages during an ambulance ride. Results: The median pressure generated under crepe bandages was 28 mmHg (interquartile range [IQR]: 17–42 mmHg) compared with 47 mmHg (IQR 26–83 mmHg) with elasticized bandages, with most subgroups applying the elasticized bandage closer to the estimated optimal pressure (55–70 mmHg). Following training, the median pressure for the 36 participants was 65 mmHg (IQR 56–71 mmHg), closer to the optimal range than initial attempts. On initial bandaging, 5/36 (14%) participants achieved optimal pressure range with elasticized bandages, compared with 18/36 (50%) after training (P = 0.002). Crepe bandages initially correctly applied did not maintain desired pressure during ambulance transport on urban roads over 30 min. Elasticized bandages maintained pressure. Conclusions: PB was poorly done by the general public and health professionals. Crepe bandages rarely generated optimal pressures compared with elasticized bandages, but training did improve participants' ability to apply elasticized bandages. PB recommendations should be modified to specify appropriate bandage types.     

Snakebite Associated Thrombotic Microangiopathy and Recommendations for Clinical Practice

Snakebite is a significant and under-resourced global public health issue. Snake venoms cause a variety of potentially fatal clinical toxin syndromes, including venom-induced consumption coagulopathy (VICC) which is associated with major haemorrhage. A subset of patients with VICC develop a thrombotic microangiopathy (TMA). This article reviews recent evidence regarding snakebite-associated TMA and its epidemiology, diagnosis, outcomes, and effectiveness of interventions including antivenom and therapeutic plasma-exchange. Snakebite-associated TMA presents with microangiopathic haemolytic anaemia (evidenced by schistocytes on the blood film), thrombocytopenia in almost all cases, and a spectrum of acute kidney injury (AKI). A proportion of patients require dialysis, most survive and achieve dialysis free survival. There is no evidence that antivenom prevents TMA specifically, but early antivenom remains the mainstay of treatment for snake envenoming. There is no evidence for therapeutic plasma-exchange being effective. We propose diagnostic criteria for snakebite-associated TMA as anaemia with >1.0% schistocytes on blood film examination, together with absolute thrombocytopenia (<150 × 10⁹/L) or a relative decrease in platelet count of >25% from baseline. Patients are at risk of long-term chronic kidney disease and long term follow up is recommended.     

Expanding donor pool by utilizing deceased donors with snake envenoming

In India, the deceased kidney transplant program is still in its preliminary stage, and accepting deceased donors with snakebite is just a forward step to expand the donor pool. We report here the outcome of 8 successful renal transplantations from brain-dead donors who died from a neurotoxic snakebite. We accepted them as donors as they had no evidence of hemotoxic snakebite. 7 recipients did well. 1 died due to sepsis with a functioning graft. 1 required renal biopsy that showed acute tubular necrosis. 1 required re-exploration due to graft collection due to a surgical issue. Patient and graft survival in follow-up were similar to other matched deceased donors in our center. According to our experience, utilizing brain-dead donors who died from a neurotoxic snakebite is safe and may dramatically expand the donor pool especially in countries where death due to snakebite is high in numbers.