Snake Bite and management Journal club.pptx

Snakebite

1. Cardiac Involvement in Vasculotoxic and Neurotoxic Snakebite – A not so Uncommon Complication MODERATOR :Dr. Sanketh PRESENTOR : Dr. Nischal Yedla

2. Journal of The Association of Physicians of India

3. Sunil Kumar K 1 Joseph K Joseph 1 Stigi Joseph 2 Abraham M Varghese 1* Manoj P Jose 1 Published in: Journal of The Association of Physicians of India ■ Vol. 68 ■ Published on November 2020 Study Duration: August 2015 to March 2017

4. Introduction WHO- 5 million snake bites every year worldwide 100,000 deaths 400,000 permanent disability. Mostly in rural areas (97%), Males (59%) > females (41%) peaked at ages 15-29 years (25%) During monsoon (June to September) Cobra ( Naja naja ), common krait ( Bungarus caeruleus), and Russell’s viper (Daboia russelii ), accounts for 97% of all snakebite related deaths.

5. Cardiotoxicity Cardiac toxicity can occur in the form of hypotension, arrhythmias, changes in electrocardiogram especially ST segment and T wave changes and myocardial infarction. There are very few case reports of pulmonary edema, myocarditis, stress cardiomyopathy in the literature due to snake bite envenomation. Cardiac complications can significantly alter the outcome of that particular bite victim and as they are commonly from resource poor settings where advanced cardiac investigations are not readily available and possible for everyone. Mechanism by which cardiac complication occurs is also not very clear, but could be a direct toxic effect on myocardium, vasospasm induced by various toxins in the venom or due to coagulopathy causing secondary cardiac damage.

6. Objectives The primary objective of the study was to assess the extent of cardiac involvement in snake bite. The secondary aims were to study the difference of cardiac involvement between neurotoxic and vasculotoxic snake bites and to analyze whether any of the clinical manifestation can predict cardiac involvement.

7. Materials and Methods Study design: This prospective observational study Conducted from August 2015 to March 2017 At tertiary referral hospital in Southern India. of which 80-90% are due to vasculotoxic snakes. Exclusion Criteria: Patients with previous renal dysfunction, previous cardiac problems, chronic liver disease, chronic obstructive pulmonary disease, preexisting neurological disorders except for completely recovered stroke were excluded from the study.

8. The procedures followed in the study were in accordance with the ethical standards of the Helsinki Declaration of the World Medical Association. The study was approved by institutional (Little Flower Hospital and Research Centre, Angamaly , Kerala, India) Ethics Committee and informed written consent was obtained from all the study participants.

9. Study procedure Detailed history was taken regarding the site of bite, application of tourniquet, vomiting, abdominal pain, and pain over the bite site, bleeding from bite site, bleeding from gums, urine output, and any neurological abnormality during admission. Vital signs including pulse rate, blood pressure, respiratory rate, temperature and oxygen saturation (SpO2) were recorded. Detailed local examination and systemic examination were performed.

10. Diagnosis Vasculotoxic envenomation was diagnosed when following a snakebite the patient had a typical clinical presentation including: limb oedema with fang marks bleeding manifestations positive 20-minute whole blood clotting test (WBCT) Snake identified by the victim or witnesses after comparing with a displayed specimen in hospital Snake was brought to the hospital dead or alive.

11. Diagnosis Neurotoxic snake bite was diagnosed with history of snake bite and any neurological signs: Drowsiness Paresthesia Abnormalities of taste and smell “heavy” eyelids, Ptosis External ophthalmoplegia Paralysis of facial muscles and other muscles innervated by the cranial nerves Nasal voice or aphonia Nasal regurgitation Difficulty in swallowing secretions Respiratory and generalized flaccid paralysis with or without signs of local envenomation

12. Cardiac involvement was defined as the presence of 1) Electrocardiographic (ECG) changes 2) Echocardiographic (ECHO) changes 3) elevation of myocardial enzymes 4) presence of any new unexplained cardiac events.

13. Investigations Investigations including complete haemogram, liver function tests, serum creatinine, ECG, ECHO and Troponin I were done in all patients with envenomation. Additional investigations including coronary angiogram and cardiac MR imaging were performed in indicated cases.

14. Treatment Patients received polyvalent ASV (Bharat Serum and Vaccines, Ltd) which was administered as per the WHO guidelines for management of snakebites. Other supportive measures were given based on clinical features, type of envenomation and organs affected.

15. Statistical methods Data were evaluated using SPSS version 24. Categorical variables were expressed as proportions and compared using chi-square test or Fisher exact test. The Student t test was used to compare mean values of normally distributed quantitative variables. Logistic regression was used to determine factors that predicted cardiac toxicity using variables that had p-value <0.05.

16. RESULTS

17. RESULTS Ninety six patients with poisonous snake bite were included in the study of which 84 (87.5%) were vasculotoxic and 12 (12.5%) were neurotoxic. Sixty two (65%) patients were males and the median age of the group was 45 ranging from 3 to 75 years. All bites were in upper or lower limbs. Whole blood clotting test time (WBCT) was prolonged in 81 (96.4%) of vasculotoxic bites and 3 (25%) of neurotoxic bites.

18. RESULTS Mean time from bite to prolongation of WBCT was 4.26 hours ranging from 1 hour to 17 hours. Swelling at the local site was described in 89 (93%) of patients, Other symptoms include abdominal pain in 16 (16.6%), vomiting in 10 (10.4%), bleeding manifestation from various sites in 15 (15.5%), regional lymph node in 40 (40.7%), hypotension in 13 (13.5%), hypertension in 15 (15.6%), acute renal injury in 35 (36.5%) and capillary leak syndrome in 10 (10.4%) patients.

19. RESULTS Cardiac involvement which was defined as any or a combination of changes described below was observed in 41 (42.7%) of patients and are summarized in Table 2. The majority was either ECG changes, noted in 33 (34.3%) and rise in troponin, noted in 21 (21.9%) patients. Other changes included Echocardiographic changes (regional wall motion abnormalities) in 4 (4.2%) and Takotsubo cardiomyopathy in 1 (1%).

20. RESULTS

21. 42.9% of vasculotoxic snake bites and 41.7% of neurotoxic snake bites developed cardiac toxicity, difference of which was not statistically significant (p=1). All patients with neurotoxic bites who developed cardiac toxicity had ECG changes, but one patient developed elevation in troponin. There was no death in the current study.

22. Binomial logistic regression was used to find any factors which could predict cardiac involvement (Table 4). Factors analysed include age, gender, type of snake, site of bite, duration of bite to whole blood clotting test time, swelling at the site of bite, abdominal pain, vomiting, bleeding from any sites, regional lymph node enlargement, hypotension, hypertension, acute renal injury and development of capillary leak syndrome. But none of these factors reached level of significance to predict cardiac involvement either in univariate or multivariate analysis.

23. Discussion In this study cardiac involvement was described in 42.7% of patients with toxic snake bite. There is a wide variation in the incidence of cardiotoxicity between various studies, major contributor might be variation in definition of various cardiotoxic features, for example some studies included all tachycardia, but some did not consider sinus tachycardia as significant abnormality. There could be other explanation like the composition of venom accounting for this variation.

24. There were no deaths observed in this study suggesting that cardiac involvement in poisonous snake bite is not a bad prognostic marker like some other complication like capillary leak syndrome. This is similar to other studies like the South Korean study which also did not see any increase in mortality with cardiotoxicity.

25. CONCLUSION In conclusion we have demonstrated that cardiac toxicity is a clearly defined toxicity following snake bite envenomation and is more common than previously thought. Neurotoxic snake bites are also associated with cardiac toxicity especially ECG abnormalities. None of the demographic factors or clinical features studied could predict the development of cardiac toxicity. Cardiac toxicity is not associated with increase in mortality, but it is important to recognize the event as it will alter the supportive management in these patients.

26. STUDY ANALYSIS Title of the study : Appropriate Sample size : Satisfactory Materials and methods: Satisfactory Results obtained : Satisfactory Clinical applicability : Applicable Conclusion : Appropriate

27. Thank You