El rol del cirujano plástico en las mordeduras por ofidios en niños: presentación de 2 casos / The role of the plastic surgeon in snake bites in children: two cases report

Las mordeduras de ofidios venenosos son lesiones potencialmente letales y continúan siendo un problema de salud en muchos países. Pueden determinar secuelas locorregionales y son más graves en los niños. Si bien existe consenso en cuanto al tratamiento sistémico, los datos acerca del tratamiento local son escasos y controversiales. Con frecuencia se convoca al cirujano plástico pediátrico para participar en el tratamiento de las heridas, el cual difiere del que solemos realizar en lesiones de otra etiología. Presentamos dos casos clínicos en los que obtuvimos excelentes resultados con el tratamiento conservador guiados por las recomendaciones del equipo de Toxicología y realizamos una revisión bibliográfica del tema. (AU)

Snake envenomation are potentially deadly accidents that still represent a public health issue in some countries. They may determine severe locoregional sequalae and are more serious in children. General treatment has been agreed, but there is little information available about adequate local management, where controversy remains. The pediatric plastic surgeon is usually involved in local treatment, which differs from standard measures applied to wound care in other situations. We present two clinical cases which, following the recommendations from toxicologists, received conservative treatment with excellent results, and we conducted a bibliographical review on the subject. (AU)

The development of surgical risk score and evaluation of necrotizing soft tissue infection in 161 Naja atra envenomed patients.

BACKGROUND: Naja atra bites cause wound necrosis, secondary infection, and necrotizing soft tissue infection (NSTI) requiring repetitive surgeries. Little information is known about the predictors for surgery after these bites. MATERIALS AND METHODS: We retrospectively evaluated 161 patients envenomed by N. atra, 80 of whom underwent surgery because of wound necrosis and infection. We compared the patients' variables between surgical and non-surgical groups. To construct a surgical risk score, we converted the regression coefficients of the significant factors in the multivariate logistic regression into integers. We also examined the deep tissue cultures and pathological findings of the debrided tissue. RESULTS: A lower limb as the bite site, a ≥3 swelling grade, bullae or blister formation, gastrointestinal (GI) effects, and fever were significantly associated with surgery in the multivariate logistic regression analysis. The surgical risk scores for these variables were 1, 1, 2, 1, and 2, respectively. At a ≥3-point cutoff value, the model has 71.8% sensitivity and 88.5% specificity for predicting surgery, with an area under the receiver operating characteristic curve of 0.88. The histopathological examinations of the debrided tissues supported the diagnosis of snakebite-induced NSTI. Twelve bacterial species were isolated during the initial surgery and eleven during subsequent surgeries. DISCUSSION AND CONCLUSIONS: From the clinical perspective, swelling, bullae or blister formation, GI effects, and fever appeared quickly after the bite and before surgery. The predictive value of these factors for surgery was acceptable, with a ≥3-point risk score. The common laboratory parameters did not always predict the outcomes of N. atra bites without proper wound examination. Our study supported the diagnosis of NSTI and demonstrated the changes in bacteriology during the surgeries, which can have therapeutic implications for N. atra bites.

Characteristics of Snakebite-Related Infection in French Guiana.

Wound infection is frequently reported following snakebite (SB). This study is retrospective. It was conducted in the emergency department and the Intensive Care Unit (ICU) of Cayenne General Hospital between 1 January 2016 and 31 July 2021. We included 172 consecutive patients hospitalized for SB envenoming. All patients were monitored for wound infection. Sixty-three patients received antibiotics at admission (36.6%). The main antibiotic used was amoxicillin-clavulanate (92.1%). Wound infection was recorded in 55 cases (32%). It was 19% in grade 1, 35% in grade 2, and 53% in grade 3. It included abscess (69.1%), necrotizing fasciitis (16.4%), and cellulitis (21.8%). The time from SB to wound infection was 6 days (IQR: 3-8). The main isolated microorganisms were A. hydrophila and M. morganii (37.5% and 18.8% of isolated organisms). Surgery was required in 48 patients (28.1%), and a necrosectomy was performed on 16 of them (33.3%). The independent factors associated with snakebite-associated infection were necrosis (p < 0.001, OR 13.15, 95% CI: 4.04-42.84), thrombocytopenia (p = 0.002, OR: 3.37, 95% CI: 1.59-7.16), and rhabdomyolysis (p = 0.046, OR: 2.29, 95% CI: 1.02-5.19). In conclusion, wound infection following SB is frequent, mainly in grade 2 and 3 envenomed patients, especially those with necrosis, thrombocytopenia, and rhabdomyolysis. The main involved bacteria are A. hydrophila and M. morganii.

Case Report: Recent Case Reports of Levant Blunt-Nosed Viper Macrovipera lebetina obtusa Snakebites in Iran.

Envenomation and death resulting from snakebites represent a significant public health problem worldwide, particularly in tropical and subtropical regions. The WHO has defined snakebite as a neglected tropical health concern. Bites from Macrovipera lebetina obtusa usually cause life-threatening systemic hemodynamic disturbances, reduced functionality of the kidneys, and other serious symptoms, including hypotension shock, edema, and tissue necrosis, at the bite site. Herein, we highlight five cases of M. l. obtusa envenomation that presented with wide-ranging manifestations. Many recovered cases were left with long-term musculoskeletal disabilities. In a particular case, a 15-year-old male patient was envenomed in his palm by an 80-cm M. l. obtusa. Within 12 hours, swelling extended to near the shoulder. Fasciotomy was performed on the forearm and part of the upper arm of this patient. Symptoms of severe localized pain and swelling, dizziness, weakness, low blood pressure, and itching around the bite area were documented. The patient remained in the hospital for 13 days.

Mesenchymal Stromal Cell-Based Therapies as Promising Treatments for Muscle Regeneration After Snakebite Envenoming.

Snakebite envenoming is a global neglected disease with an incidence of up to 2.7 million new cases every year. Although antivenoms are so-far the most effective treatment to reverse the acute systemic effects induced by snakebite envenoming, they have a limited therapeutic potential, being unable to completely neutralize the local venom effects. Local damage, such as dermonecrosis and myonecrosis, can lead to permanent sequelae with physical, social, and psychological implications. The strong inflammatory process induced by snake venoms is associated with poor tissue regeneration, in particular the lack of or reduced skeletal muscle regeneration. Mesenchymal stromal cells (MSCs)-based therapies have shown both anti-inflammatory and pro-regenerative properties. We postulate that using allogeneic MSCs or their cell-free products can induce skeletal muscle regeneration in snakebite victims, improving all the three steps of the skeletal muscle regeneration process, mainly by anti-inflammatory activity, paracrine effects, neovascularization induction, and inhibition of tissue damage, instrumental for microenvironment remodeling and regeneration. Since snakebite envenoming occurs mainly in areas with poor healthcare, we enlist the principles and potential of MSCs-based therapies and discuss regulatory issues, good manufacturing practices, transportation, storage, and related-procedures that could allow the administration of these therapies, looking forward to a safe and cost-effective treatment for a so far unsolved and neglected health problem.

Case reports of envenomation and venom composition differences between two Arizona populations of the Southwestern Speckled Rattlesnake, Crotalus pyrrhus (Cope, 1867).

Envenomations by the Southwestern Speckled Rattlesnake (Crotalus pyrrhus) are fairly rare. Previous descriptions in the literature do not include locality, an important factor in the clinical symptoms or syndromes of snakebites resulting from geographic variation in venom composition. Here, we describe two cases of envenoming by C. pyrrhus from two Arizona localities (Tinajas Altas Mountains, Yuma County, and Phoenix Mountains, Maricopa County). Both patients experienced swelling, but neither demonstrated coagulopathy, thrombocytopenia, or hypofibrinogenemia. The Phoenix Mountains patient developed hemorrhagic bullae and tissue damage in his bitten extremity, necessitating the amputation of the distal portion of his middle finger. Treatment for both consisted of medication for pain, isotonic crystalloid, and antivenom therapy with recovery in each case. Based on visual inspection of 1D-gels and RP-HPLC chromatograms, venom samples were largely similar but appeared to differ quantitatively for several toxin families between and within populations.

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.

Surgical Considerations for Pediatric Snake Bites in Low- and Middle-Income Countries.

BACKGROUND: Snake envenomation is associated with major morbidity especially in low- and middle-income countries and may require fasciotomy. We determined patient factors associated with the need for fasciotomy after venomous snake bites in children located in KwaZulu-Natal, South Africa. METHODS: Single institutional review of historical data (2012-2017) for children (<18 years) sustaining snake envenomation was performed. Clinical data, management, and outcomes were abstracted. Syndromes after snake bite were classified according to Blaylock nomenclature: progressive painful swelling (PPS), progressive weakness (PW), or bleeding (B), as it is difficult to reliably identify the species of snake after a bite. Comparative and multivariable analyses to determine factors associated with fasciotomy were performed. RESULTS: There were 72 children; mean age was 7 (±3) years, 59% male. Feet were most commonly affected (n = 27, 38%) followed by legs (n = 18, 25%). Syndromes (according to Blaylock) included PPS (n = 63, 88%), PW (n = 5, 7%), and B (n = 4, 5%). Eighteen patients underwent fasciotomy, and one required above knee amputation. Nine patients received anti-venom. Few patients (15%) received prophylactic beta-lactam antibiotics. Hemoglobin < 11 mg/dL, leukocytosis, INR >1.2, and age-adjusted shock index were associated with fasciotomy. On regression, age-adjusted shock index and hemoglobin concentration < 11 mg/dL, presentation >24 h after snake bite, and INR >1.2 were independently associated with fasciotomy. Model sensitivity was 0.89 and demonstrated good fit. CONCLUSIONS: Patient factors were associated with the fasciotomy. These factors, coupled with clinical examination, may identify those who need early operative intervention. Improving time to treatment and the appropriate administration of anti-venom will minimize the need for surgery. LEVEL OF EVIDENCE: III.

Case Report: Bothrops lanceolatus Snakebite Surgical Management-Relevance of Fasciotomy.

Bothrops lanceolatus is an endemic Crotalidae species in Martinique, where approximately 30 cases of envenoming are managed yearly. Envenoming characteristics from Bothrops species include local tissue damage, systemic bleeding, and hemodynamic alterations. We hereby report a case of severe envenomation following B. lanceolatus snakebite to the right calf. Severe local manifestations developed progressively up to the lower limb despite adequate antivenom therapy. Systemic manifestations of venom also occurred, resulting in intensive care therapy. Surgery exploration revealed soft tissue necrosis, friability of the deep fascia, and myonecrosis. The patient needed multiple debridement procedures and fasciotomy of all leg compartments and anterior compartment of the thigh. Diagnosis of necrotizing fasciitis was confirmed by positive Aeromonas hydrophila blood cultures. This clinical case illustrates that major soft tissue infection, including necrotizing fasciitis may occur after snakebite. Abnormal coagulation tests should not delay surgical management, as severe envenoming is a life-threatening condition.

Severe snakebite envenomation in French Guiana: When antivenom is not available.

In French Guiana, Bothrops atrox, Bothrops brazili, Bothrops bilineatus, Lachesis muta and Micrurus sp are responsible for most cases of snakebite envenomation. The clinical features in patients suffering from envenomations by viperid snakes involve local tissue damage and systemic manifestations, such as hemorrhage, coagulopathies and hemodynamic instability. We report a severe case of envenomation in a patient bitten by a large unidentified pit viper in French Guiana. Due to lack of antivenom, the patient only received symptomatic management. Severe manifestations of local and systemic envenomation developed, and the patient needed multiple debridement procedures and ultimately required a transfemoral amputation. In addition, Aeromonas hydrophila was cultivated from the affected tissue, suggesting that infection contributed to necrotizing fasciitis. This case highlights the clinical features of a severe viperid snakebite envenomation, and illustrates the urgent need to ensure accessibility of effective and safe polyvalent viperid antivenom in French Guiana.

Snakebite poisoning in Spain. / Envenenamiento por mordedura de serpiente en España.

OBJECTIVES: Emergencies due to snakebites, although unusual in Spain, are potentially serious. Of the 13 species native to the Iberian peninsula, only 5 are poisonous: 2 belong to the Colubridae family and 3 to the Viperidae family. Bites from these venemous snakes can be life-threatening, but the venomous species can be easily identified by attending to certain physical traits. Signs denoting poisoning from vipers, and the appropriate treatment to follow, have changed in recent years.

OBJETIVO: Las urgencias por mordeduras de serpientes ibéricas en España son poco frecuentes pero potencialmente graves. De las trece especies autóctonas, sólo cinco son venenosas (2 especies de colúbridos y las 3 especies de vipéridos) y pueden suponer un riesgo para la vida del paciente. La identificación de las especies puede ser sencilla teniendo en cuenta una serie de rasgos del ofidio. Las manifestaciones clínicas debidas al envenenamiento de las víboras, así como su tratamiento, han experimentado modificaciones en los últimos años.

[Amputation of a limb secondary to snakebite in a child]. / Amputation de membre secondaire à une morsure de vipère.

Amputation of a limb is a serious consequence of snakebite poisoning. It is caused by the toxicity of the venom and often the use of a tourniquet in some patients, which can lead to limb ischemia. Management of the victim aims to ensure survival and preserve the function of the bitten limb. Antivenom immunotherapy is the only specific treatment for ophidian envenomation. It is indicated in cases of general symptoms and signs related to the bite, but also if local damage could lead to the loss of limb function. The authors report on a case of snakebite that led to amputation at the thigh.

Algorithmic approach to the prevention of unnecessary fasciotomy in extremity snake bite.

BACKGROUND: In the literature, there is a lack of a consensus about the occurrence of the compartment syndrome due to the snake bites. There are different concepts for the surgical treatment of the threshold value of the chamber pressure. There are many different classifications and assessment criteria for the snakebites. PURPOSE: There is not any appropriate classification in order to the assessment of extremity snake bites while making a decision for fasciotomy. We aimed to standardize the follow-up and decision making to perform fasciotomy with a new classification system for the snakebites using objective data. PATIENTS AND METHODS: The data of all patients were recorded prospectively between 2006 and 2011. A total of 97 patients (64 male, 33 female) with a mean age of 30.94±14.04 were followed-up. During the evaluation of the patients, we used a new classification system that was improved for the extremity bites. We classified the patients due to their signs into four groups as for the classification system. RESULTS: 40 patients with compartment like symptoms were carefully followed for 48-72h, and only three patients required fasciotomy where full recovery was achieved in 37 patients. Coverage of the defects was performed with full thickness skin grafting in 4 patients and cross finger flap in two patient. In two patients, the defects were located on the palmar aspect of the thumb. Thus, we applied Kite flap for skin coverage. Reverse dorsal digital artery flap was performed in eight patients and dorsal interosseous metacarpal flap in six patients. Four patients underwent an amputation. Two patients had web reconstruction due to first web contracture. CONCLUSIONS: We present a large series of snake bite injuries and propose a classification and treatment recommendations. Fasciotomy should only be done while the measurement of intra-compartment pressure is above 55mmHg as snakebite can mimic the compartment syndrome. LEVEL OF EVIDENCE: III-IV.

Can surgical need in patients with Naja atra (Taiwan or Chinese cobra) envenomation be predicted in the emergency department?

OBJECTIVES: To investigate the clinical predictors and the aetiologies for surgery in patients with Naja atra (Taiwan or Chinese cobra) envenomation. METHODS: This case series was conducted in the only tertiary care centre in eastern Taiwan. Patients who presented to the emergency department with Naja atra bite between January 2008 and September 2014 were included. Clinical information was collected and compared between surgical and non-surgical patients. RESULTS: A total of 28 patients with Naja atra envenomation presented to the emergency department during the study period. Of these, 60.7% (n=17) required surgery. Necrotising fasciitis (76.5%) was the main finding in surgery. Comparisons between surgical and non-surgical patients showed skin ecchymosis (odds ratio=34.36; 95% confidence interval, 2.20-536.08; P=0.012) and a high total dose of antivenin (≥6 vials; odds ratio=14.59; 95% confidence interval, 1.10-192.72; P=0.042) to be the most significant predictors of surgery. The rate of bacterial isolation from the surgical wound was 88.2%. Morganella morganii (76.5%), Enterococcus faecalis (58.8%), and Bacteroides fragilis (29.4%) were the most common pathogens involved. Bacterial susceptibility testing indicated that combined broad-spectrum antibiotics were needed to cover mixed aerobic and anaerobic bacterial infection. CONCLUSIONS: Patients with Naja atra envenomation who present with skin ecchymosis or the need for a high dose of antivenin may require early surgical assessment. Combined broad-spectrum antibiotics are mandatory.

The Management of Domestic Animal Bites to the Hand.

Hand bites from domestic animals are extremely common. Though many may initially appear benign, it is important for treating physicians to be aware of the factors that place patients sustaining animal bites at additional risk for infection. As clinicians, we must be able to efficiently diagnose and treat these patients properly to avoid the morbidity that animal bites can provoke. The current paper reviews the evaluation and management of domestic animal bites to the hand.

Snakebite is Under Appreciated: Appraisal of Burden from West Africa.

BACKGROUND: Snakebite envenoming (SBE) is a major problem in rural areas of West Africa (WA). Compared to other Neglected Tropical Diseases (NTD), the public health burden of SBE has not been well characterized. We estimated the impact of snakebite mortality and morbidity using the Disability Adjusted Life Years (DALYs) metrics for 16 countries in WA. METHODS: We used the reported annual number of SB deaths and mean age at time of SB and converted these into years of life lost (YLL). Similarly, the years of life lived with disability (YLD) were estimated by multiplying the number of amputations by the respective disability weight of 0.13. RESULTS: In WA, the annual cases of SB mortality and amputations ranged from 24 (95% Confidence Interval: 19-29) and 28 (17-48) respectively in Guinea-Bissau with the highest estimates of 1927 (1529-2333) and 2368 (1506-4043) respectively in Nigeria. We calculated that the annual DALYs associated with a SB death ranged from 1550 DALYs (95%CI: 1227-1873 DALYs) in Guinea Bissau to 124,484 DALYs (95%CI: 98,773-150,712 DALYs) in Nigeria. The annual DALYs associated with amputation for the two countries were 149 DALYs (95%CI: 91-256 DALYs) and 12,621 DALYs (95%CI: 8027-21,549 DALYs) respectively. The total burden of SBE was estimated at 319,874 DALYs (95% CI: 248,357-402,654 DALYs) in the 16 countries in WA. These estimates are similar, and in some instances even higher, than for other NTDs encountered in WA (e.g., Buruli ulcer, Echinococcosis, Intestinal Nematode Infections, Leishmaniasis, Onchocerchiasis, Trachoma and Trypanosomiasis) as reported in the Global Burden of Diseases 2010 (GBD). CONCLUSIONS: The public health burden of SBE in WA is very substantial and similar to other more widely recognized NTDs. Efforts and funding commensurate with its burden should be made available for the control of snakebite in the sub-region.

Snakebite in Korea: A Guideline to Primary Surgical Management.

PURPOSE: Snakebite is an emergency which causes local symptoms such as pain and edema around the bite. Systemic symptoms may also develop, such as dizziness or renal failure, and may even cause death. The purpose of this research was to assess the validity and safety of snakebite protocol for surgery when treating snakebite patients. MATERIALS AND METHODS: Retrospective research was performed on patients who were admitted after being treated at the emergency center from January 2008 to December 2012. When necessary, debridement was also performed, and 46 of 111 patients (41.4%) underwent debridement. Those who had received debridement without antivenom administration due to a positive skin reaction test were classified as group A, and group B received antivenom and delayed debridement. We reviewed the emergency and admission charts of the patients in each group and recorded and compared their age, sex, bite site, severity of local and general symptoms, time to receive antivenin, and complications. RESULTS: Of the ten patients (21.7%) in group A, two (66.6%) developed cellulites, and one of them experienced skin necrosis, resulting in a skin graft. In group B, there were 36 patients (78.2%), 19 (52.7%) of whom developed cellulitis. Skin necrosis occurred in two patients, and one of these patients received a skin graft. Compartment syndrome was found in one patient, and fasciotomy and a skin graft were performed. CONCLUSION: The treatment protocol implemented to treat snakebite patients admitted to the emergency center during this research was safely and properly followed during surgical treatment.

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

BACKGROUND: Fasciotomy has been described in the treatment of rattlesnake-envenomation. We sought to compare the characteristics of patients undergoing fasciotomy with those where fasciotomy was discussed but not performed. METHODS: A retrospective case-series constructed from a single-statewide-poison-system electronic database for cases of fasciotomy discussion or completion in rattlesnake-envenomation between January 2001 and May 2012. Age, gender, bite location, antivenom administered, compartment pressure measurements, Snakebite Severity Score (SSS) and length of hospitalization (LOS) were recorded. Comparisons were made between fasciotomy completed and where fasciotomy was only discussed. RESULTS: One-hundred-five cases of fasciotomy discussion or completion were identified. Fasciotomy was performed in 28 cases (27%). There was no statistically significant difference (p > 0.05) between groups in age, gender, bite site, SSS, and total number of vials of antivenom administered. Only 2 of 28 (7%) had compartment pressure measurements. Patients undergoing fasciotomy spent an additional 2 days in the hospital. CONCLUSIONS: Fasciotomies continue to take place, without compartment pressure measurements, and without repeat dosing of antivenom. In the absence of clear objective evidence that limb-threatening compartment syndrome occurs despite adequate antivenom administration, fasciotomy does not favorably impact morbidity and may be associated with increased costs for care following rattlesnake envenomation.

Calcific myonecrosis following snake bite: a case report and review of the literature.

INTRODUCTION: Calcific myonecrosis is a rare condition in which muscle in a limb compartment undergoes necrosis and becomes peripherally calcified with central liquefaction. The patient usually presents with a slowly progressive enlarged mass that sometimes can be misdiagnosed as soft tissue sarcoma. Most of the reported cases showed that the disease occurs often after trauma or compartment syndrome. However, the case of calcific myonecrosis following snake bite is rarely reported. CASE PRESENTATION: A 66-year-old Thai woman presented with a gradually progressive enlarged mass over a period of 10 years in her left leg. She had a history of untreated compartment syndrome after she was bitten by a snake (Malayan pit viper) in her left leg when she was 14-years old. At presentation, a plain X-ray showed a large soft tissue mass at the anterior compartment of her left leg. A sheet-like mass with an enlarged central cavity combined with peripheral calcification and cortical erosion of her tibia were observed. A biopsy was performed and the result was negative for neoplastic cells. During a 5-year follow-up, the mass progressively enlarged and then became infected and finally broke through the skin. She was treated by excision of the mass and administration of antibiotics. The wound completed healed at 1 month postsurgery. There was no wound complication or disease recurrence at 1 year postoperation. CONCLUSIONS: The diagnosis of calcific myonecrosis was done by history taking and radiographic interpretation. In an asymptomatic patient the management should be observation and clinical follow-up. A biopsy should be avoided due to the high rate of postoperative infection. Treatment of choice in a symptomatic condition is mass excision.