Snake Envenomation
Posted: Wednesday, September 13th, 2023 | Updated: Wednesday, September 13th, 2023
Posted: Wednesday, September 13th, 2023 | Updated: Wednesday, September 13th, 2023
General Information:
In the southeastern United States, we see a few different types of snake bites present to our facility. We tend to see a lot of copperhead snake bites and an occasional rattlesnake bite. Rarely, do we encounter others. Snake bites are usually pretty painful and patients will typically present with puncture wounds and swelling near the site of envenomation. That swelling tends to spread and worsen during the initial hours and subsides within 2-5 days. If the swelling is around the neck, patients may experience trouble breathing. If the swelling is around the mouth, patients may not be interested in eating for a day or so. Tissue damage, necrosis, sloughing and bruising may also occur at the site of envenomation. Clipping and a gentle cleaning of the wound may be performed. Patients more significantly impacted may experience coagulation or bleeding problems and/or hypotension. These patients may benefit from blood product administration and intravenous fluid therapy. Patients who have a potential life-threatening reaction may benefit from anti-venom
In the southeastern United States, we see a few different types of snake bites present to our facility. We tend to see a lot of copperhead snake bites and an occasional rattlesnake bite. Rarely, do we encounter others. Snake bites are usually pretty painful and patients will typically present with puncture wounds and swelling near the site of envenomation. That swelling tends to spread and worsen during the initial hours and subsides within 2-5 days. If the swelling is around the neck, patients may experience trouble breathing. If the swelling is around the mouth, patients may not be interested in eating for a day or so. Tissue damage, necrosis, sloughing and bruising may also occur at the site of envenomation. Clipping and a gentle cleaning of the wound may be performed. Patients more significantly impacted may experience coagulation or bleeding problems and/or hypotension. These patients may benefit from blood product administration and intravenous fluid therapy. Patients who have a potential life-threatening reaction may benefit from anti-venom
Cases of Snake Envenomation
Patient #1: Young Female Canine (Larger Breed)
Presentation: Febrile, painful, puncture wound on lip and tongue, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova)
Diagnosis: Copperhead snake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Hydromorphone during her stay and an injection of carprofen at discharge), anti-nausea (Cerenia), and maintenance intravenous fluid therapy. The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Presentation: Febrile, painful, puncture wound on lip and tongue, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova)
Diagnosis: Copperhead snake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Hydromorphone during her stay and an injection of carprofen at discharge), anti-nausea (Cerenia), and maintenance intravenous fluid therapy. The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Patient #2: Senior Female Canine (Medium-sized Breed)
Presentation: Tachycardic, painful, puncture wound on nose, slight elevated aPTT, heart murmur II/IV, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test
Diagnosis: Copperhead snake bite likely
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone and gabapentin during her stay) and maintenance intravenous fluid therapy. The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Presentation: Tachycardic, painful, puncture wound on nose, slight elevated aPTT, heart murmur II/IV, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test
Diagnosis: Copperhead snake bite likely
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone and gabapentin during her stay) and maintenance intravenous fluid therapy. The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Patient #3: Senior Female Canine (Large Breed)
Presentation: Hypersalivation, painful, puncture wound on muzzle, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova)
Diagnosis: Copperhead snake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone during her stay) and maintenance intravenous fluid therapy. The patient was sent home with gabapentin for any associated pain
Presentation: Hypersalivation, painful, puncture wound on muzzle, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova)
Diagnosis: Copperhead snake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone during her stay) and maintenance intravenous fluid therapy. The patient was sent home with gabapentin for any associated pain
Patient #4: Senior Male Canine (Large Breed)
Presentation: Tachycardia, painful, puncture wound and swelling on distal forelimb, slightly elevated PT, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test, small animal profile, complete blood count
Diagnosis: Copperhead snake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone initially and then a Fentanyl CRI during the stay) and 1.5x maintenance intravenous fluid therapy. The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Presentation: Tachycardia, painful, puncture wound and swelling on distal forelimb, slightly elevated PT, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test, small animal profile, complete blood count
Diagnosis: Copperhead snake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone initially and then a Fentanyl CRI during the stay) and 1.5x maintenance intravenous fluid therapy. The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Patient #5: Young Female Canine (Large Breed)
Presentation: Tachycardia, high normal temperature, hypertensive, injected mucous membranes, painful, puncture wound and swelling on muzzle, elevated PT and aPTT, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test, small animal liver profile, complete blood count, blood type, ECG
Diagnosis: Pygmy rattlesnake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone initially and then a Fentanyl CRI during the stay), anti-nausea therapy (Cerenia), maintenance intravenous fluid therapy, and a single vial of anti-venom (Given over 1 hour). The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Presentation: Tachycardia, high normal temperature, hypertensive, injected mucous membranes, painful, puncture wound and swelling on muzzle, elevated PT and aPTT, echinocytes on blood smear
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test, small animal liver profile, complete blood count, blood type, ECG
Diagnosis: Pygmy rattlesnake bite
Treatment Included: Supportive care in hospital for 24 hours with pain management (Methadone initially and then a Fentanyl CRI during the stay), anti-nausea therapy (Cerenia), maintenance intravenous fluid therapy, and a single vial of anti-venom (Given over 1 hour). The patient was eating at discharge and was sent home with an anti-inflammatory drug (Carprofen), as well as, gabapentin for any additional pain
Patient #6: Young Female Canine (Small Breed)
Presentation: Tachycardia, hypotension, hypothermia, hyperlactatemia, hematochezia, progressive anemia, puncture wound on ear/head, bruising where blood drawn at referring veterinarian, echinocytes on blood smear, elevated aPTT, hemolysis, progressive pigmenturia, dull to obtunded mentation, previous anti-venin administration at referring veterinarian
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test, complete blood count, blood type, ECG
Diagnosis: Rattlesnake bite
Treatment Included: Supportive care in hospital with pain management (Fentanyl, Lidocaine, Ketamine CRI), anti-nausea therapy (Cerenia), gastrointestinal support (Pantoprazole), intravenous fluid therapy, packed red blood cells, fresh frozen plasma bolus followed by a CRI, and antibiotic therapy in case of GI translocation (Unasyn). The patient was eventually started on a Metoclopramide CRI due to GI ileus and was given another vial of anti-venin over 30 minutes due to a lack of improvement. Zinc Oxide paste was applied to perineum for scalding protection. A dose of Hypertonic Saline and Naloxone was given for a progressive decline in mentation. The patient's bloodwork also worsened over time. CK and bilirubin levels increased, the patient became azotemic, a low albumin and potassium were also noted (supplementation with potassium chloride was initiated), urine outputs were measured, a central line was placed through a saphenous vein, and more GI meds were started (Ondansetron and Sucralfate). A feeding tube was placed for aspiration of GI contents, as well as, for nutritional support. The patient was manually rotated in the kennel and her head was elevated slightly. Passive range of motion exercises (PROM) were performed. Another antibiotic was started (Enrofloxacin) and liver protectants were added (N-Acetylcysteine). Occasional VPCs were noted on her ECG. The patient was thought potentially to have suffered a stroke like event during the hospitalization and despite continued efforts, the patient ultimately declined
Presentation: Tachycardia, hypotension, hypothermia, hyperlactatemia, hematochezia, progressive anemia, puncture wound on ear/head, bruising where blood drawn at referring veterinarian, echinocytes on blood smear, elevated aPTT, hemolysis, progressive pigmenturia, dull to obtunded mentation, previous anti-venin administration at referring veterinarian
Diagnostics: Blood smear, baseline bloodwork (Nova), coagulation test, complete blood count, blood type, ECG
Diagnosis: Rattlesnake bite
Treatment Included: Supportive care in hospital with pain management (Fentanyl, Lidocaine, Ketamine CRI), anti-nausea therapy (Cerenia), gastrointestinal support (Pantoprazole), intravenous fluid therapy, packed red blood cells, fresh frozen plasma bolus followed by a CRI, and antibiotic therapy in case of GI translocation (Unasyn). The patient was eventually started on a Metoclopramide CRI due to GI ileus and was given another vial of anti-venin over 30 minutes due to a lack of improvement. Zinc Oxide paste was applied to perineum for scalding protection. A dose of Hypertonic Saline and Naloxone was given for a progressive decline in mentation. The patient's bloodwork also worsened over time. CK and bilirubin levels increased, the patient became azotemic, a low albumin and potassium were also noted (supplementation with potassium chloride was initiated), urine outputs were measured, a central line was placed through a saphenous vein, and more GI meds were started (Ondansetron and Sucralfate). A feeding tube was placed for aspiration of GI contents, as well as, for nutritional support. The patient was manually rotated in the kennel and her head was elevated slightly. Passive range of motion exercises (PROM) were performed. Another antibiotic was started (Enrofloxacin) and liver protectants were added (N-Acetylcysteine). Occasional VPCs were noted on her ECG. The patient was thought potentially to have suffered a stroke like event during the hospitalization and despite continued efforts, the patient ultimately declined