Factor deficiencies in venom‐induced consumption coagulopathy resulting from Australian elapid envenomation: Australian Snakebite Project (ASP‐10)

Summary. Background: Limited information exists on the dynamics of hemostasis in patients with venom‐induced consumption coagulopathy (VICC) from snake envenomation. Objective: The aim of the present study was to investigate specific factor deficiencies and their time course in Australasian elapid envenomation. Methods: We measured coagulation parameters and factor concentrations in patients recruited to the Australian Snakebite Project, an observational cohort study. There were 112 patients with complete VICC, defined as an international normalized ratio (INR) > 3, and 18 with partial VICC. Serial citrated plasma samples were collected from 0.5 to 60 h post‐bite. INR, activated partial thromboplastin time (aPTT), coagulation factors (F)I, II, V, VII, VIII, IX, X, von Willebrand factor antigen (VWF:Ag) and D‐dimer concentrations were measured. Results: Complete VICC was characterized by near/total depletion of fibrinogen, FV and FVIII, with an INR and aPTT that exceeded the upper limits of detection, within 2 h of snakebite. Prothrombin levels never fell below 60% of normal, suggesting that the toxins were rapidly eliminated or inactivated and re‐synthesis of clotting factors occurred irrespective of antivenom. Partial VICC caused limited depletion of fibrinogen and FV, and almost complete consumption of FVIII. Onset of VICC was more rapid with brown snake (Pseudonaja spp.) venom, which contains a group C prothrombin activator toxin, compared with the tiger snake group, which contains a group D prothrombin activator toxin and requires human FVa formation. Resolution of VICC occurred within 24–36 h irrespective of snake type. Conclusions: These results suggest that Australasian elapid prothrombin activators have a potent but short duration of action. Antivenom is unlikely to be administered in time to prevent VICC.     

A Localizing Circumferential Compression Device Increases Survival after Coral Snake Envenomation to the Torso of an Animal Model

Background: Pressure immobilization bandages have been shown to delay onset of systemic toxicity after Eastern coral snake (Micrurus fulvius) envenomation to the distal extremity. Objectives: To assess the efficacy of a novel compression device in delaying onset of systemic toxicity after truncal envenomations with Eastern coral snake (Micrurus fulvius) venom in a porcine model. Methods: With University approval, nine juvenile pigs (11 kg to 22 kg) were sedated, anesthetized, and intubated but not paralyzed to ensure continuous spontaneous respirations in a university animal laboratory. Each animal was injected subcutaneously with 10 mg of M. fulvius venom in a pre-selected area of the trunk. After 1 min, six animals had the application of a novel, localizing circumferential compression (LoCC) device applied to the bite site (treatment group) and three animals had no treatment (control group). The device was composed of a rigid polymer clay form molded into a hollow fusiform shape with an internal dimension of 8 × 5 × 3 cm and an elastic belt wrapped around the animal securing the device in place. Vital signs were recorded at 30-min intervals. End points included a respiratory rate below 3 breaths/min, oxygen saturation < 80%, or survival to 8 h. Survival to 8 h was analyzed using Fisher's exact test, with p < 0.05 indicating significance. Survival analysis was performed using the Mantel-Cox test to assess time to death with outcomes represented in a Kaplan-Meier Cumulative survival plot. Results: Five of the six pigs in the treatment group survived 8 h (293-480 min). None of the control pigs survived to 8 h (Fisher's exact p = 0.04), with mean time of respiratory failure 322 min (272-382 min). Survival analysis showed a significant delay in time to event in the treatment group compared to the control group (p = 0.04). Conclusions: The LoCC device used in this study delayed the onset of systemic toxicity and significantly increased survival time after artificial truncal envenomation by Eastern coral snake venom.     

A clinical and neurophysiological study of scorpion envenomation in Assiut, Upper Egypt

Scorpion envenomation (SE) represents an agonizing problem in many countries, especially in rural areas. This clinical and neurophysiological study aimed to determine the relative frequency of scorpion envenomation in the Assiut area, in Upper Egypt. Full clinical evaluation was carried out for all children ≤18 y of age included in the study. Electroencephalography (EEG), electromyography (EMG) and motor conduction velocity measurements were carried out for a variable number of children. SE was recorded in 302 cases per year in this area. Of these, 78.5% were ≤18 y of age. SE occurred most commonly during the summer months. Clinical evaluation revealed that SE results in marked autonomic manifestations, principally sinus tachycardia (78.1%), vomiting (70.5%) and hyperthermia (53.2%). It also results in many neuropsychiatric manifestations, such as agitation and restlessness (17.7%) and disturbance of consciousness (8.0%). Electroencephalographic study of 184 cases of SE in paediatric patients aged ≤18 y revealed abnormalities in 77.7%. Study of mean distal latency and motor conduction velocity revealed that patients had a significantly shorter distal latency and a more rapid motor conduction velocity compared with the control group. This was true for both the inflicted limb and the contralateral limb. Most of the complications of SE are due to irritability of the central and peripheral nervous systems.     

REVERSIBLE PARASYMPATHETIC DYSAUTONOMIA FOLLOWING STINGING ATTRIBUTED TO THE BOX JELLY FISH (CHIRONEX FLECKERI)

Following a box jelly fish sting, a 52 year old Chinese fisherman developed acute abdominal distension, inability to pass urine and failure of erection.
Examination revealed gaseous abdominal distension and a distended urinary bladder. Absence of lachrimation and absence of changes in the R-R interval in the ECG during breathing and carotid sinus massage gave further evidence of parasympathetic dysautonomia. The patient made a complete recovery. The case highlights the occurrence of reversible parasympathetic dysautonomia following box jelly fish sting.     

Neuromodulation of Neuropathic Pain Syndrome Induced by Elapidae (Cobra) Envenomation

Objectives. This study aims to demonstrate the utility of spinal cord stimulation in a neuropathic pain syndrome and overall decline in health and functional independence following elapid envenomation in a morbidly obese, insulin‐dependent diabetic. Materials and Methods. A two‐lead, 16‐electrode constant‐current, independently controlled system is placed in the mid‐cervical spine. Results. Noted were a improvement in overall health status with better glycemic control and return to work status in response to adequate pain control. Conclusions. The case serves as a model for other orphan pain cases with a seemingly esoteric etiology and adds to the existing body of literature that spinal cord stimulation and neuromodulation, in general, has a wide‐ranging applicability peripheral neuropathic pain syndromes.     

Respiratory compromise in patients with rattlesnake envenomation

Respiratory compromise after rattlesnake envenomation (RSE) is an uncommon yet potentially lethal complication. We were interested in determining the frequency of respiratory compromise in patients treated for RSE. The incidence and indications for intubation were also determined. A retrospective chart review was conducted of all patients treated by medical toxicologists at a tertiary referral hospital between July, 1994 and November, 2000. Out of 294 total patients, 289 charts were reviewed. Of all 289 patients, 214 (74%) received Crotalidae Polyvalent Antivenin (Wyeth-Ayerst) and 23 (8%) had clinical evidence of respiratory compromise. Thirteen of 289 patients (4.4%) were intubated following RSE. No one was intubated for antivenin-induced complications. There were no deaths among studied patients during acute hospitalization. Respiratory compromise following RSE is rare, occurring in only 8% of studied patients. Only 2 patients (0.7%) required intubation as a direct consequence of RSE. No one required intubation for antivenin-induced hypersensitivity reactions.     

Asp Viper (Vipera aspis) envenomation: experience of the Marseille Poison Centre from 1996 to 2008

A retrospective case review study of viper envenomations collected by the Marseille's Poison Centre between 1996 and 2008 was performed. RESULTS: 174 cases were studied (52 grade 1 = G1, 90 G2 and 32 G3). G1 patients received symptomatic treatments (average hospital stay 0.96 day). One hundred and six (106) of the G2/G3 patients were treated with the antivenom Viperfav* (2.1+/-0.9 days in hospital), while 15 of them received symptomatic treatments only (plus one immediate death) (8.1+/-4 days in hospital, 2 of them died). The hospital stay was significantly reduced in the antivenom treated group (p < 0.001), and none of the 106 antivenom treated patients had immediate (anaphylaxis) or delayed (serum sickness) allergic reactions. CONCLUSION: Viperfav* antivenom was safe and effective for treating asp viper venom-induced toxicity.