COAGULATION PROFILE AND ANALYSIS OF OUTCOME OF BLOOD COMPONENT THERAPY IN SNAKE BITE VICTIMS

Transcription

1 COAGULATION PROFILE AND ANALYSIS OF OUTCOME OF BLOOD COMPONENT THERAPY IN SNAKE BITE VICTIMS Dr Aboobacker Mohamed Rafi 1, Dr Susheela J Innah Senior Resident Department of Transfusion Medicine Jubilee Mission Medical College & Research Institute Kerala

2 BACKGROUND Bites from poisonous snakes cause substantial human morbidity and mortality in tropical and subtropical countries. Hemotoxic envenoming is quite common in many parts of India, but only limited data exist on its accurate incidence in the country, and clinical effects.

3 AIM AND OBJECTIVES To assess the coagulation profile in snake bite patients & to assess the outcome of blood component therapy in them

4 Material and Methods Prospective Observational Study January 2013 to June 2014 Patients admitted in the Medical ICU,with a history of hematotoxic snake bite Detailed clinical examination and investigations were done to assess the status of envenomation.

5 20 min Whole Blood Clotting Time (WBCT) * is used as the screening test to say that the patient has a hematotoxic snake bite. Repeated every 30 minutes for 4 times and if any one value is prolonged the patient is taken as having received a hematotoxic snake bite. If it was a diagnosed case of PIT viper bite, 20min WBCT was done 6hrly for 3 to 5 days * David AW. Guidelines for the clinical management snake bite. In: Guidelines for the clinical management snake bite, 2nd edition. WHO Library

6 If the 20 min WBCT is prolonged, other tests are also done which includes platelet count, BT, PT, INR, aptt, fibrinogen and factor XIII screening. A citrated sample is collected at the time of deranged 20min WBCT, the plasma is separated and frozen as fast as possible for later tests on specific coagulation factor assays.

7 RESULTS A total of 595 snake bite patients had come to our hospital during this time period There were 445 adult patients and the rest were pediatric patients. 282 snake bites were considered non venomous as they did not show any signs of envenomation. 163 snake bite patients showed some sign of envenomation, were admitted in Medical ICU and were given Anti SnakeVenom.

8 50% of the venomous bites,the species of the snakes could not be identified Of the identified snake bites 66 patients were bitten by Russell s viper. 9 patients were bitten by Pit viper snakes 2 patients were bitten by kraits 4 patients were bitten by cobra

9 Clinical Manifestations Bleeding from the bite site was the most common clinical manifestation. Echymosis, purpura, hematoma and hematuria were the other predominant clinical features. Local manifestations and systemic manifestations were more severe in patients who received delayed treatment. Acute renal failure due to DIC & capillary leak syndrome was found only in patients with Russell s viper bite. Among the patients who developed ARF, dialysis was required for patients with Russell s viper bite only.

10 Bleeding Manifestations vs. Snake species

11 Coagulation Tests Coagulation screen (20 min WBCT, BT, Platelet count,pt,inr, aptt & Fibrinogen) was deranged for most of the Russell viper and Pit viper patients. The aptt and Fibrinogen were rarely requested.

12 32.5 % OF THE SNAKE BITES HAD AN INITIAL PROLONGED 20 WBCT 3% HAD HA NORMAL INITIAL 20 min WBCT BUT A LATER PROLONGATION- PIT VIPER

13 Only 3 % of the patients had a prolonged bleeding time, and they were associated with a low platelet count

14 95% of the patients with prolonged 20 min WBCT had a prolonged PT/INR

15 57% of the bite victims were not tested for aptt 13.5% of those patients tested, had a prolonged aptt

16 20 patients had both PT & aptt prolonged

17 SPECIFIC FACTOR ASSAYS Coagulation Factor assays (V,VII,VIII,IX &X) were done on all the Russell viper and Pit viper patient samples which were frozen In all Russell s Viper bite patients factor V and factor X deficiency were noted In Pit viper bite patients the clotting factors were normal in these patients even though the coagulation screen was abnormal Factor XIII qualitative test was done and it was found to be deficient in cases of Russell Viper bites only

18 Blood Component Transfusion

19 Statistically significant increase in duration of hospital stay was seen in those who were transfused irrespective of the blood component.

20 There were no adverse events/transfusion reactions reported due to blood component transfusion No statistical significance in other complications or mortality were seen due to Transfusion

21 FFP USAGE The usual protocol followed was, to give ASV initially and check for 20 min WBCT, PT& INR the next day. If it was not corrected, 4 units of FFP were ordered by the treating physician All the patients who had received a blood product, was transfused with FFP (mean dosage 4 units).

22 We did see a lot of disparity in the indication of FFP for the snake bite patients in our hospital as there is no strict guidelines on the use of blood products in snake bite coagulopathy. There was a statistically significant increase in the duration of hospital stay in these patients which could be due to the fact that the patients who were transfused were,per say patients who did not show improvement with ASV within 24 hrs.

23 RDP USAGE Random Donor Platelets was given to seven patients who had thrombocytopenia with bleeding manifestations. Three patients required more than 10 units of RDP which was due to autoimmune destruction of platelets causing bleeding.

24 None of the patients who received platelet transfusion died One patient had associated severe autoimmune hemolytic anemia along with severe thrombocytopenia

25 PRBC TRANSFUSION Four patients required PRBC due to bleeding. The hemoglobin values ranged from 6.8 to 9 gm/dl in these patients. Each person was given only one unit of PRBC. None of the patients who received PRBC had died One patient had gone into transient renal failure requiring renal dialysis.

26 CRYOPRECIPITATE None of the patients were given Cryoprecipitate To note :In our study, we had found out that most of the Russell s viper patients had reduced Factor XIII and Fibrinogen; for which cryoprecipitate could have been used to supplement these factors, without causing much renal injury.

27 General Outcome

28 Mortality 11 patients had expired in our study group. 6 patients who died were due to renal failure after Russell s viper bite None of the Pit viper bite patients died There was no statistically significant correlation between transfusion and death of the patients. All the patients who had expired had capillary leak syndrome along with DIC leading to ARF and subsequently death.

29 Limitations of the study Most of the snake bites were due to unknown or unidentified snakes. Samples of all the bite patients could not be analyzed fully, either due to unavailability of the sample or early death of the patient or improper collection leading to hemolysis /fibrin formation in the sample.

30 CONCLUSION Continuing education and training programs for those involved in management of snake bite patients have to be introduced An institutional protocol for lab investigations and hemotherapy in snake bite patients has to be formulated.

31 Cryoprecipitate to be used as factor XIII and fibrinogen deficiency was seen in most of the snake bite patients. Public awareness programs have to be conducted so as to spread the message of snake bite prevention, first aid and early treatment which are the main pillars of adequate snake bite management.

32 References 1. David AW. Injuries, envenoming, poisoning, and allergic reactions caused by animals. In: David AW, Timothy MC, John DF, editors. Oxford textbook of medicine, 5th edition. Oxford university press, 2010: p David AW. Guidelines for the clinical management snake bite. In: Guidelines for the clinical management snake bite, 2nd edition. WHO Library Cataloguing in Publication, New Delhi, Bhat RN. Viperine snakebite poisoning in Jammu. Journal of the Indian Medical Association, 1974; 63: Mohapatra BN, Nayak K, Rath RN. Coagulation disorder following viper bite in Orissa. J ournal of Indian Medical Association, 1992: 90: Myint L. Bites by Russell's Viper in Burma: Hemostatic, Vascular, and Renal disturbances and responses to treatment". Lancet, 1985; 2:

33