A chance to cut is not always a chance to cure- fasciotomy in the treatment of rattlesnake envenomation: A retrospective poison center study

Fasciotomy following North American pit viper envenomation in Texas 2004-2021

INTRODUCTION

North American pit viper envenomation occurs over 4,000 times annually in the United States, with polyvalent Fab antivenom being the primary treatment. Fasciotomy is occasionally performed due to concerns about compartment syndrome. We utilized our direct access to Texas Poison Center Network data to create a new snakebite abstraction form and database on relevant available information between 2004 and 2021 and to identify, describe, and estimate the incidence of fasciotomy following pit viper envenomation in Texas.

METHODS

We searched the Texas Poison Center Network database for cases during 2004-2021 using keywords such as fasciotomy, surgery, compartment pressure, and compartment syndrome. Descriptive statistics summarized the data.

RESULTS

Of 16,911 reported envenomations, 0.69 percent involved fasciotomies (n = 117). Most common bite sites were digits/hands and lower extremities. Patients who underwent fasciotomy were typically male, aged 20-59, and 10 years younger than the total snakebite population. Only 6 percent of reported compartment syndrome cases had a compartment pressure measurement. Antivenom was administered in 101 (86.3 percent) cases, 92 (91.1 percent) of which received only Fab antivenom product. Patients with bites from rattlesnakes (47.9 percent) were associated with most fasciotomies.

DISCUSSION

Our findings suggest a potential increase in snakebite exposures, accompanied by a decrease in fasciotomies. Overall, copperheads constituted the majority of snakebites, but most fasciotomies were from rattlesnake envenomations (47.9 percent). In this cohort, compartment syndrome diagnosis and decisions regarding fasciotomy were primarily based on clinical evaluation/surgeon expertise without compartment pressure measurements. Despite the efficacy of antivenom, only 86.3 percent of patients in our study received antivenom.

CONCLUSIONS

Fasciotomy after North American pit viper envenomation in Texas is uncommon (0.69 percent) and has decreased over time, possibly due to increased antivenom use or surgeon comfort with nonsurgical management.

Refractory compartment syndrome after antivenom administration for an Eastern Diamondback Rattlesnake bite requiring fasciotomy for limb salvage: A case report

Case

56-year-old male who developed post-snakebite compartment syndrome (PSCS) of the upper extremity which was refractory to antivenom administration. He had elevated compartment pressure measurements in his upper extremity. He underwent open fasciotomy for the compartment syndrome, followed by delayed primary closure and skin grafting. He now has two years of follow-up with a functional upper extremity.

Conclusion

This is a case of a patient who suffered post-snakebite compartment syndrome from his pet Eastern Diamondback Rattlesnake. This case highlights the importance of correctly diagnosing compartment syndrome and validates fasciotomy as a treatment measure for confirmed post-snakebite compartment syndrome (PSCS).

Medically important snakes and snakebite envenoming in Iran

Snakebite is a common health condition in Iran with a diverse snake fauna, especially in tropical southern and mountainous western areas of the country with plethora of snake species. The list of medically important snakes, circumstances and effects of their bite, and necessary medical care require critical appraisal and should be updated regularly. This study aims to review and map the distributions of medically important snake species of Iran, re-evaluate their taxonomy, review their venomics, describe the clinical effects of envenoming, and discuss medical management and treatment, including the use of antivenom. Nearly 350 published articles and 26 textbooks with information on venomous and mildly venomous snake species and snakebites of Iran, were reviewed, many in Persian (Farsi) language, making them relatively inaccessible to an international readership. This has resulted in a revised updated list of Iran's medically important snake species, with taxonomic revisions of some, compilation of their morphological features, remapping of their geographical distributions, and description of species-specific clinical effects of envenoming. Moreover, the antivenom manufactured in Iran is discussed, together with treatment protocols that have been developed for the hospital management of envenomed patients.

Snakebites in Jordan: A clinical and epidemiological study

The epidemiology features and clinical symptoms associated with 121 cases of snakebite requiring admission to 24 hospitals in Jordan, during 2018-2020, are discussed. Ninety-six of them (79%) brought with them to the hospital the snake that bit them or a photograph of it. Echis coloratus was responsible for 68 of the bites and 6 fatalities. Sex ratio was 3.2 males: 1 female, with an overall average age of 27 ± 14.36 years. The highest incidence of bites was reported in September. Bites were most common on hands and legs. The period of hospitalization ranged from 1 to 36 days. Irbid and Karak governorates had the highest number of snakebites, most cases being reported from agricultural areas and among farmers. Clinical symptoms associated with five species of venomous snakes are described along with illustrative case histories. Symptoms associated with Echis coloratus bites included local swelling and necrosis, coagulopathy and bleeding, microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury (AKI) and chronic renal failure. Daboia palaestinae victims exhibited ecchymoses, local swelling and necrosis, with one case of angioedema. Other symptoms included thrombocytopenia, coagulopathy, microangiopathic hemolysis and local and systemic bleeding, as well as AKI. A single case of envenoming by Macrovipera lebetinus developed the following symptoms; swelling, severe pain, extensive ecchymoses, neutrophil leukocytosis, normochromic normocytic anemia and aggregated platelets with thrombocytopenia. Symptoms associated with two cases of Pseudocerastes fieldi included swelling that spread from bitten hands, and mild abnormalities of platelet count and bleeding time. Four cases of envenoming by Atractaspis engaddensis exhibited severe pain, local swelling, erythema, numbness and tissue necrosis. One of them developed acute systemic symptoms. The only antivenom currently available in Jordan, is VINS "Snake venom antitoxin (Biosnake)", manufactured in India using venoms of three African snakes that do not occur in Jordan. It proved clinically ineffective against envenoming by Jordanian Viperidae, failing to correct coagulopathy and life-threatening hemorrhage, and to prevent AKI.

Simultaneous open fracture and rattlesnake bite on the same extremity

Open fractures and rattlesnake envenomations are two emergencies that each require emergent intervention and treatment. While each is common, when they occur simultaneously on the same extremity, it creates a syndrome that is quintessential Central Texas. We present the case of a 13-year-old boy who sustained a lower-extremity rattlesnake envenomation with concomitant open tibia and fibula fractures after being thrown from an all-terrain vehicle. The envenomation from the snake bite compelled us to first treat his developing coagulopathy with a delayed operative management of his fractures.

Moderate-to-severe Vipera berus envenoming requiring ViperaTAb antivenom therapy in the UK

BACKGROUND

Bites by the European adder (Vipera berus) in the UK are uncommon but potentially life threatening, and can be associated with marked limb swelling and disability. Following an interruption in Zagreb Imunološki zavod antivenom supply around 2012, the UK changed its national choice of antivenom for Vipera berus to ViperaTAb, an ovine Fab monospecific antivenom. In the absence of randomised controlled trials, we established an audit to review its use in clinical practice.

METHODS

A prospective audit of ViperaTAb use was conducted from March 2016 until November 2020 by the UK National Poison Information Service (NPIS). Users of the NPIS online toxicology database, TOXBASE, considering the use of antivenom for V. berus envenoming were invited to discuss the case with the on-call clinical toxicology consultant. Information was collected prospectively on indications, administration, adverse reactions and outcome of patients administered ViperaTAb antivenom.

RESULTS

One hundred and seventy patients were administered ViperaTAb antivenom over five years. One hundred and thirty-two were adults and 38 children (median age and range: 38, 2-87 years). Bites occurred across the UK, but most commonly in coastal regions of Wales and of South-West and East England. Median time to presentation was 2.1 (IQR 1.5-4.0) h and to antivenom administration from presentation was 2.0 (IQR 0.9-3.6) h. A minority of patients presented to hospital more than 12 h after being bitten (n = 19, 11.2%) or received antivenom more than 12 h after presenting to hospital (n = 17, 10.0%). Features of systemic envenoming were present in 64/170 (37.6%) patients, including 23 (13.5%) with anaphylaxis and 26 (15.3%) with hypotension (nine with both). Clinician assessment considered the initial antivenom to have been effective in 122/169 (72.2%) patients. Repeated dosing was common, occurring in 55/169 (32.5%), predominantly due to persisting or worsening local effects (46/51, 90.2%). There were three cases of probable early adverse reaction. No deaths occurred during the study. Complications of envenoming were rare but included four patients that underwent surgery, three patients each with acute kidney injury, mild coagulopathy, or thrombocytopenia (one severe). The median duration of hospital stay was 43.7 (IQR 22.5-66.5) h, longer for children than adults (52.5 vs 41.3 h).

CONCLUSION

ViperaTAb antivenom appears to be effective and safe and should be administered as soon as possible for patients meeting clinical criteria. Patients require close observation following antivenom to detect adverse reactions and progression or recurrence of envenoming. Close collaboration with expert NPIS consultant advice can help optimise antivenom timing, ensure repeated dosing is given appropriately, and avoid unnecessary surgical intervention. All hospitals, particularly those located in areas of relatively high incidence, should stock sufficient antivenom available at short notice, 24 h a day.

How Should Native Crotalid Envenomation Be Managed in the Emergency Department?

BACKGROUND

Pit vipers, also known as crotalids, are a group of snakes including rattlesnakes, copperheads, and cottonmouths (water moccasins). Crotalids have a broad geographic distribution across the United States, and bites from these snakes can carry significant morbidity. Their envenomations are characterized by local tissue effects, hematologic effects, and systemic effects. Envenomations are generally treated with 1 of 2 antivenoms available in the United States.

OBJECTIVE

We developed a series of clinical questions to assist and guide the emergency physician in the acute management of a patient envenomated by a crotalid.

METHODS

We conducted a PubMed literature review from January 1970 to May 2020 in English for articles with the keywords "bite" and "crotalidae."

RESULTS

Our literature search resulted in 177 articles. A total of 33 articles met criteria for rigorous review and citation in the development of these consensus guidelines.

CONCLUSIONS

Patients should be initially evaluated, stabilized, and assessed for local effects, hematologic effects, and systemic toxicity suggestive of envenomation. Antivenom should be given if toxic effects are present. Surgical intervention including debridement and fasciotomy should be avoided. Prophylactic antibiotics are not necessary.

Caring for patients with venomous Crotalinae snakebites

Venomous snakebites are surprisingly common in the US. This article provides an overview of what to do when a patient has been bitten by a North American pit viper, a venomous subset of indigenous snakes.

Envenomation by a western green mamba (Dendroaspis viridis) - A report of three episodes in Switzerland

The African elapid snake genus Dendroaspis comprises four species, with D. polylepsis the most dangerous of them. D. viridis is believed to cause stronger neurotoxic symptoms than the potentially least toxic of the genus, D. angusticeps, but seems less toxic compared to either of the D. jamesoni species (D. j. jamesoni(TRAILL 1843) and D. j. kaimosae (Loveridge 1936)). We present three episodes of bites byD. viridis in the same patient, sustained on three different occasions, caused by three different and unrelated snakes. While the first bite remained oligosymptomatic with a slight tightness of the throat and speedy resolution of symptoms without specific therapy, episodes two and three resulted in the patient developing massive local swelling. However, the patient showed only minimal neurologic and systemic symptoms such as tightness of the throat and a tingling sensation of the body. Episode two resolved with fasciotomy after compartment syndrome was diagnosed with a measured intracompartmental pressure of 52 mmHg. In episode three, antivenom was administered with good resolution of symptoms. The clinical courses in this patient were remarkable as he displayed mainly local symptoms after three individual bites by a supposedly neurotoxic snake.

The Epidemiology, Clinical Course, and Management of Snakebites in the North American Snakebite Registry

The American College of Medical Toxicology established the North American Snakebite Registry (NASBR), a national database of detailed, prospectively collected information regarding snake envenomation in the United States, in 2013. This report describes the epidemiology, clinical course, and management of snakebites in the NASBR. All cases entered into the NASBR between January 1, 2013 and December 31, 2015 were identified. Descriptive statistics are used to report results. Fourteen sites in 10 states entered 450 snakebites. Native species comprised 99% of cases, almost all of which were pit viper bites. 56.3% were identified as rattlesnakes and 29.4% as copperheads. 69.3% were male and 28.2% were children age 12 and under. Fifty-four percent of bites were on the lower extremity. Twenty-seven percent of patients with lower extremity bites were not wearing shoes. Common tissue findings associated with envenomation were swelling, ecchymosis, and erythema. Systemic effects and hematologic toxicity were more common in rattlesnake than copperhead or cottonmouth envenomations. Crotalidae Polyvalent Immune Fab antivenom was given to 84% of patients. Twelve patients (4.3%) were re-admitted to the hospital after completion of treatment. Eight were re-treated with antivenom. The NASBR gathers detailed data on venomous snakebites across the US. In its initial years, useful information has already been gained. Data regarding footwear will inform public health interventions and education, and information regarding the clinical presentation may help physicians better anticipate effects and manage snakebite. As the number of cases in the NASBR grows, associations between patient-related factors and outcomes may be studied.

Snakebite envenoming

Snakebite envenoming is a neglected tropical disease that kills >100,000 people and maims >400,000 people every year. Impoverished populations living in the rural tropics are particularly vulnerable; snakebite envenoming perpetuates the cycle of poverty. Snake venoms are complex mixtures of proteins that exert a wide range of toxic actions. The high variability in snake venom composition is responsible for the various clinical manifestations in envenomings, ranging from local tissue damage to potentially life-threatening systemic effects. Intravenous administration of antivenom is the only specific treatment to counteract envenoming. Analgesics, ventilator support, fluid therapy, haemodialysis and antibiotic therapy are also used. Novel therapeutic alternatives based on recombinant antibody technologies and new toxin inhibitors are being explored. Confronting snakebite envenoming at a global level demands the implementation of an integrated intervention strategy involving the WHO, the research community, antivenom manufacturers, regulatory agencies, national and regional health authorities, professional health organizations, international funding agencies, advocacy groups and civil society institutions.

Animal, Microbial, and Fungal Borne Skin Pathology in the Mountain Wilderness: A Review

Mountains are home to numerous organisms known to cause skin disease. Bites, stings, poisons, chemicals, toxins, trauma, and infections all contribute to this end. Numerous plants, animals, fungi, bacteria, viruses, and protozoa are responsible. This paper aims to review skin illness and injury sustained from organisms in the mountains of North America. Other factors such as increased ultraviolet radiation, temperature extremes, and decreasing atmospheric pressure along with human physiologic parameters, which contribute to disease severity, will also be discussed. After reading this review, one should feel more comfortable identifying potentially harmful organisms, as well as diagnosing, treating, and preventing organism-inflicted skin pathology sustained in the high country.