1
|
Lai L, Xie L, Chen Y, Du W, Yang X, Liu W, Shangguan P, Xu J, Lan P. The establishment and evaluation of a swine model of deinagkistrodon acutus snakebite envenomation. Toxicon 2024; 241:107683. [PMID: 38460604 DOI: 10.1016/j.toxicon.2024.107683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 02/24/2024] [Accepted: 03/06/2024] [Indexed: 03/11/2024]
Abstract
OBJECTIVE To establish a preclinical large-animal model of Deinagkistrodon acutus snakebite envenomation and evaluate its feasibility. METHODS The venom of D. acutus (0 mg/kg, 1 mg/kg, 2 mg/kg, 5 mg/kg, or 10 mg/kg) was injected into the left biceps femoris of 11 male pigs. Then, the circumferences of the limbs were regularly measured, and changes in muscle injury biomarkers, blood parameters, coagulation function, vital organ function and injury biomarkers were regularly detected. At 24 h after venom injection, the animals were euthanized, and the pathological damage to the vital organs mentioned above was evaluated. RESULTS The two pigs receiving 10 mg/kg and 5 mg/kg snake venom died at 8 h and 12 h after injection, respectively. The remaining pigs were equally divided into 0 mg/kg, 1 mg/kg, and 2 mg/kg snake venom groups, and all of them survived to 24 h after injection. Compared with the pigs receiving 0 mg/kg snake venom, the pigs receiving 1 mg/kg or 2 mg/kg snake venom exhibited significant abnormities, including limb swelling; increased muscle injury biomarker creatine kinase (CK) and coagulation function indicators prothrombin time and D-dimer; and decreased blood routine indicator platelet and coagulation function indicator fibrinogen. Moreover, significant abnormalities in myocardial and cerebral function and injury biomarkers in the heart, brain, liver, kidney and intestine were also observed. In particular, the abnormalities mentioned above were significantly obvious in those pigs receiving 2 mg/kg snake venom. Pathological evaluation revealed that the morphology of muscle, heart, brain, liver, kidney, and intestine in those pigs receiving 0 mg/kg snake venom was normal; however, pathological damage was observed in those pigs receiving 1 mg/kg and 2 mg/kg snake venom. Similarly, the pathological damage was more severe in those pigs receiving 2 mg/kg snake venom. CONCLUSION The intramuscular injection of 2 mg/kg D. acutus venom seems to be an optimal dose for examining the preclinical efficacy of existing and novel therapeutics for treating D. acutus envenomation in pigs.
Collapse
Affiliation(s)
- Linjie Lai
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Lutao Xie
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Yi Chen
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Wang Du
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Xuelin Yang
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Wanjuan Liu
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Peixin Shangguan
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| | - Jiefeng Xu
- Department of Emergency Medicine, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Pin Lan
- Department of Emergency Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Central Hospital, Lishui Hospital of Zhejiang University, Lishui, China.
| |
Collapse
|
2
|
Lindquist DG, Valente JH, Hack JB. A Pilot Study Testing the Novel Use of a Snake Bite Compression Device for Field Hemostasis and Wound Repair in an Animal Model. Mil Med 2024; 189:461-465. [PMID: 35861270 DOI: 10.1093/milmed/usac223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/18/2022] [Accepted: 07/14/2022] [Indexed: 11/12/2022] Open
Abstract
INTRODUCTION A commercially available snake bite device was pilot tested for novel use as a method of hemostasis and wound repair at a noncompressible site in a live swine model. The device is light, is plastic, uses a hook-and-loop strap attachment, and is easily deployed. The device could offer a method for the field repair of an actively bleeding laceration at a noncompressible site in an austere environment. MATERIALS AND METHODS This was an interventional, prospective, controlled study in a large animal model. The study was approved by the Rhode Island Hospital Institutional Review Board (IRB) and the Animal Welfare Committee/Institutional Animal Care and Use Committee and the Lifespan Research Conflict of Interest Committee. Each animal acted as its own control. Blood loss was measured and compared between repairs of standardized incisions with and without the device's application. The lacerations were sutured closed. Two proceduralists alternated tasks of wound repair versus blood collection. Blood loss was measured by using gauze sponges to capture the blood during a 30-second free-bleeding period and during the repair itself. Using a one sample t-test (the expected difference in blood loss between the two incision repair methods = 0 if the null hypothesis were true), we calculated the mean difference in the deltas between the repair methods. RESULTS The mean delta difference was 3.1 g (SE ± 0.97). The t-test demonstrated that there was a significantly greater blood loss during the standard repair method, t(9) = 3.11, P < 0.01 than during the repair with the device in place (see Fig. 2). A statistical power analysis conducted showed that with a sample size of 10 animals, there was sufficient statistical power to detect this significant effect (β = 0.82, α < 0.05, one-tailed). CONCLUSIONS There was statistically significantly less blood loss during the repairs with the device's application. This feasibility experiment demonstrates that a commercially available snakebite device may be useful for hemostasis during laceration repair at anatomic sites not amenable to application of tourniquets or compressive dressings. Strengths of the study include the prospective controlled design, including the use of each animal as its own control; alternating proceduralists to account for any variability in suturing efficiency; and the statistical significance of the results despite the small number of subjects. One weakness is that the time required for each repair was not measured. The device's portability and reusability suggest applicability in austere medical environments. Future studies could include timing the repairs, using a skin stapler or wound adhesive instead of sutures, applying a hemostatic agent before the repair, and sequentially applying the device to wounds longer than the device.
Collapse
Affiliation(s)
- David G Lindquist
- Department of Emergency Medicine, Alpert Medical School of Brown University, Providence, RI 02903, USA
| | - Jonathan H Valente
- Department of Emergency Medicine, Alpert Medical School of Brown University, Providence, RI 02903, USA
- Department of Pediatrics, Alpert Medical School of Brown University, Hasbro Children's Hospital, Providence, RI 02903, USA
| | - Jason B Hack
- Department of Emergency Medicine, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| |
Collapse
|
3
|
Parker-Cote J, Meggs WJ. First Aid and Pre-Hospital Management of Venomous Snakebites. Trop Med Infect Dis 2018; 3:E45. [PMID: 30274441 PMCID: PMC6073535 DOI: 10.3390/tropicalmed3020045] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/15/2018] [Accepted: 04/16/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Antivenom is the definitive treatment for venomous snakebites, but is expensive and not available in many rural and poorly developed regions. Timely transportation to facilities that stock and administer antivenom may not be available in rural areas with poorly developed emergency medical services. These factors have led to consideration of measures to delay onset of toxicity or alternatives to antivenom therapy. METHODS PubMed searches were conducted for articles on snakebite treatment, or that contained first aid, emergency medical services, tourniquets, pressure immobilization bandages, suction devices, and lymphatic flow inhibitors. RESULTS The reviewed articles describe how venoms spread after a venomous snakebite on an extremity, list the proposed first aid measures for delaying the spread of venoms, and evaluate the scientific studies that support or refute methods of snakebite first aid. The recommendations for field treatment of venomous snakebites will be discussed. CONCLUSIONS The evidence suggests that pressure immobilization bandages and related strategies are the best interventions to delay onset of systemic toxicity from venomous snakebites but may increase local toxicity for venoms that destroy tissue at the site of the bite, so their use should be individualized to the circumstances and nature of the venom.
Collapse
Affiliation(s)
- Jennifer Parker-Cote
- Division of Toxicology, Department of Emergency Medicine, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA.
| | - William J Meggs
- Division of Toxicology, Department of Emergency Medicine, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA.
| |
Collapse
|
4
|
Fry BG. Snakebite: When the Human Touch Becomes a Bad Touch. Toxins (Basel) 2018; 10:E170. [PMID: 29690533 PMCID: PMC5923336 DOI: 10.3390/toxins10040170] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 04/19/2018] [Accepted: 04/20/2018] [Indexed: 01/08/2023] Open
Abstract
Many issues and complications in treating snakebite are a result of poor human social, economic and clinical intervention and management. As such, there is scope for significant improvements for reducing incidence and increasing patient outcomes. Snakes do not target humans as prey, but as our dwellings and farms expand ever farther and climate change increases snake activity periods, accidental encounters with snakes seeking water and prey increase drastically. Despite its long history, the snakebite crisis is neglected, ignored, underestimated and fundamentally misunderstood. Tens of thousands of lives are lost to snakebites each year and hundreds of thousands of people will survive with some form of permanent damage and reduced work capacity. These numbers are well recognized as being gross underestimations due to poor to non-existent record keeping in some of the most affected areas. These underestimations complicate achieving the proper recognition of snakebite’s socioeconomic impact and thus securing foreign aid to help alleviate this global crisis. Antivenoms are expensive and hospitals are few and far between, leaving people to seek help from traditional healers or use other forms of ineffective treatment. In some cases, cheaper, inappropriately manufactured antivenom from other regions is used despite no evidence for their efficacy, with often robust data demonstrating they are woefully ineffective in neutralizing many venoms for which they are marketed for. Inappropriate first-aid and treatments include cutting the wound, tourniquets, electrical shock, immersion in ice water, and use of ineffective herbal remedies by traditional healers. Even in the developed world, there are fundamental controversies including fasciotomy, pressure bandages, antivenom dosage, premedication such as adrenalin, and lack of antivenom for exotic snakebites in the pet trade. This review explores the myriad of human-origin factors that influence the trajectory of global snakebite causes and treatment failures and illustrate that snakebite is as much a sociological and economic problem as it is a medical one. Reducing the incidence and frequency of such controllable factors are therefore realistic targets to help alleviate the global snakebite burden as incremental improvements across several areas will have a strong cumulative effect.
Collapse
Affiliation(s)
- Bryan G Fry
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia, QLD 4072, Australia.
| |
Collapse
|
5
|
Iron protects porcine plasma coagulation kinetics from degradation by Crotalus atrox venom. Biometals 2017; 30:677-683. [DOI: 10.1007/s10534-017-0035-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 07/12/2017] [Indexed: 12/23/2022]
|
6
|
Smyrnioudis ME, O'Rourke DP, Rosenbaum MD, Brewer KL, Meggs WJ. Long-term efficacy of pressure immobilization bandages in a porcine model of coral snake envenomation. Am J Emerg Med 2014; 32:1024-6. [PMID: 25059885 DOI: 10.1016/j.ajem.2014.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 05/23/2014] [Accepted: 06/03/2014] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Pressure immobilization bandages delay mortality for 8 hours after coral snake envenomation, but long-term efficacy has not been established. OBJECTIVE The objective of this study is to determine the long-term efficacy of pressure immobilization bandages after coral snake envenomation in the absence of antivenom therapy. METHODS A randomized, observational pilot study was conducted. Ten pigs (17.3-25.6 kg) were sedated, intubated for 5 hours, and injected subcutaneously with 10 mg of lyophilized Micrurus fulvius venom resuspended in water. Pigs were randomly assigned to a control group (no treatment) or a treatment group (compression bandage and splint) approximately 1 minute after envenomation. Bandage pressure was not controlled. Pigs were monitored daily for 21 days for signs of respiratory depression, decreased oxygen saturations, and paralysis. In case of respiratory depression, pigs were humanely euthanized and time to death recorded. Statistical analysis was performed with Fisher exact test, Mann-Whitney U test, and Kaplan-Meier survival curve as appropriate. RESULTS Median survival time of control animals was 307 minutes compared with 1172 minutes in treated animals (P = .10). Sixty percent of pigs in the treatment group survived to 24 hours vs 0% of control pigs (P = .08). Two of the treatment pigs survived to the end point of 21 days but showed necrosis of the distal lower extremity. CONCLUSIONS Long-term survival after coral snake envenomation is possible in the absence of antivenom with the use of pressure immobilization bandages. The applied pressure of the bandage is critical to allowing survival without necrosis. Future studies should be designed to accurately monitor the pressures applied.
Collapse
Affiliation(s)
- Mary E Smyrnioudis
- Department of Emergency Medicine, Brody School of Medicine at East Carolina University, Greenville NC
| | - Dorcas P O'Rourke
- Department of Comparative Medicine, Brody School of Medicine at East Carolina University, Greenville NC
| | - Matthew D Rosenbaum
- Department of Comparative Medicine, Brody School of Medicine at East Carolina University, Greenville NC
| | - Kori L Brewer
- Department of Emergency Medicine, Brody School of Medicine at East Carolina University, Greenville NC
| | - William J Meggs
- Department of Emergency Medicine, Brody School of Medicine at East Carolina University, Greenville NC.
| |
Collapse
|
7
|
van Helden DF, Thomas PA, Dosen PJ, Imtiaz MS, Laver DR, Isbister GK. Pharmacological approaches that slow lymphatic flow as a snakebite first aid. PLoS Negl Trop Dis 2014; 8:e2722. [PMID: 24587472 PMCID: PMC3937289 DOI: 10.1371/journal.pntd.0002722] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 01/17/2014] [Indexed: 11/18/2022] Open
Abstract
Background This study examines the use of topical pharmacological agents as a snakebite first aid where slowing venom reaching the circulation prevents systemic toxicity. It is based on the fact that toxin molecules in most snake venoms are large molecules and generally first enter and traverse the lymphatic system before accessing the circulation. It follows on from a previous study where it was shown that topical application of a nitric oxide donor slowed lymph flow to a similar extent in humans and rats as well as increased the time to respiratory arrest for subcutaneous injection of an elapid venom (Pseudonaja textilis, Ptx; Eastern brown snake) into the hind feet of anaesthetized rats. Methodology/Principal Findings The effects of topical application of the L-type Ca2+ channel antagonist nifedipine and the local anesthetic lignocaine in inhibiting lymph flow and protecting against envenomation was examined in an anaesthetized rat model. The agents significantly increased dye-measured lymph transit times by 500% and 390% compared to controls and increased the time to respiratory arrest to foot injection of a lethal dose of Ptx venom by 60% and 40% respectively. The study also examined the effect of Ptx venom dose over the lethal range of 0.4 to 1.5 mg/kg finding a negative linear relationship between increase in venom dose and time to respiratory arrest. Conclusions/Significance The findings suggest that a range of agents that inhibit lymphatic flow could potentially be used as an adjunct treatment to pressure bandaging with immobilization (PBI) in snakebite first aid. This is important given that PBI (a snakebite first aid recommended by the Australian National Health and Medical research Council) is often incorrectly applied. The use of a local anesthetic would have the added advantage of reducing pain. Snakebite remains a major problem worldwide causing death or serious illness in many tens of thousands of victims annually. An approach to reduce the burden of envenoming is to provide optimum first aid procedures. We have previously shown that topical application of a nitric oxide (NO) donor slowed lymph flow to similar extent in humans and rats as well as increased the time to respiratory arrest by ∼50% for subcutaneous injection of eastern brown snake venom into the hind feet of anaesthetized rats. The present study examines the use of several other topical pharmacological agents that aim to slow venom toxins reaching the circulation through the lymphatic system. The study found that the agents examined were similarly effective to that previously found for the NO donor. The fact that one of these is a commonly used topical local anesthetic may be an ideal adjunct first aid, as it provides first aid while reducing pain.
Collapse
Affiliation(s)
- Dirk F. van Helden
- School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- * E-mail:
| | - Paul A. Thomas
- School of Medicine, University of Queensland, Brisbane, Queensland, Australia
- Department of Nuclear Medicine, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
| | - Peter J. Dosen
- School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
| | - Mohammad S. Imtiaz
- School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
| | - Derek R. Laver
- School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
| | - Geoffrey K. Isbister
- School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia
- Department of Clinical Toxicology and Pharmacology, Calvary Mater Newcastle, Waratah, New South Wales, Australia
| |
Collapse
|
8
|
Lefkowitz RY, Taylor J, Balfe D. Reality bites: a case of severe rattlesnake envenomation. J Intensive Care Med 2012; 28:314-9. [PMID: 22588374 DOI: 10.1177/0885066612446415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Rattlesnake venoms can cause a wide range of adverse human health effects. However, with the availability of modern antivenin, toxicity can generally be minimized and controlled. We present a rare case of rattlesnake envenomation resulting in severe systemic effects and syndrome relapse. Management considerations and patient course are described in the context of the current literature.
Collapse
Affiliation(s)
- Rafael Y Lefkowitz
- Department Fellow of Internal Medicine, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | | | | |
Collapse
|
9
|
Gilliam LL, Brunker J. North American snake envenomation in the dog and cat. Vet Clin North Am Small Anim Pract 2012; 41:1239-59. [PMID: 22041214 DOI: 10.1016/j.cvsm.2011.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Snake envenomation can be a cause of significant morbidity in dogs and cats in North America. Being familiar with the venomous snakes in your area and understanding the mechanisms of action of their venom will allow for successful treatment of envenomation cases. Treatment of snake envenomation revolves around supportive care in mild to moderate cases and venom neutralization with antivenom in severe cases. Dogs and cats envenomated by North American snakes have a good prognosis if treated appropriately.
Collapse
Affiliation(s)
- Lyndi L Gilliam
- Center for Veterinary Health Sciences, Department of Veterinary Clinical Sciences, Oklahoma State University, 1 Farm Road-BVMTH, Stillwater, OK 74078, USA
| | | |
Collapse
|
10
|
A pharmacological approach to first aid treatment for snakebite. Nat Med 2011; 17:809-11. [PMID: 21706027 DOI: 10.1038/nm.2382] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Accepted: 04/19/2011] [Indexed: 11/09/2022]
Abstract
Snake venom toxins first transit the lymphatic system before entering the bloodstream. Ointment containing a nitric oxide donor, which impedes the intrinsic lymphatic pump, prolonged lymph transit time in rats and humans and also increased rat survival time after injection of venom. This pharmacological approach should give snakebite victims more time to obtain medical care and antivenom treatment.
Collapse
|