Evaluation of changes in perfusion index in patients with cytotoxic tissue damage after snake bite: A prospective cohort study

• Main Authors: Evren Büyükfırat, Mahmut Alp Karahan
• Format: Article
• Language: English
• Published: Journal of Surgery and Medicine 2019-09-01
• Series: Journal of Surgery and Medicine
• Subjects: yılan ısırması; antivenom; perfüzyon indeksi; zehir; snakebite; perfusion index; venom
• Online Access: https://dergipark.org.tr/en/pub/josam/issue/48398/621050

Aim: Pain, edema, and heat loss that develop and gradually increase in the extremities following a snake bite reduce microcirculation. The perfusion index indicates the intensity of the pulsatile signal relative to the nonpulsatile signal. The aim of this study was to measure the changes in perfusion index (PI) in the extremities of patients suffering from a snake bite who are treated in an intensive care unit, to detect early ischemia or necrosis in the affected organ, and to investigate the effectiveness of the administered antivenom.Methods: Twenty patients admitted to our hospital with cytotoxic swelling of the upper or lower extremities after a snake bite were included in this prospective cohort study. Initial treatment was provided to the patients based on the snake bite treatment protocol. PI values of the affected extremity of each patient were measured for 24 hours using a finger probe and compared with the unaffected extremity in the same region. Patient age, gender, bites, antivenom administration times, and complications were also recorded and compared.Results: Of all patients, 13 (65%) were male and 7 (35%) were female. The mean age of the patients was 37.5 (14.15) years. Eight patients (40%) were bitten in the lower extremity, and 12 patients (60%) were bitten in the upper extremity. PI values measured at the 19th, 23rd, and 24th hours were significantly higher in the affected extremity than in the unaffected extremity (P=0.043, P=0.049 and P=0.018, respectively). PI values measured at the 20th, 21st, and 22nd hours were insignificantly higher in the affected extremity than in the unaffected extremity (P=0.088, P=0.096 and P=0.085, respectively). An increase in the ratio between the PI of the unaffected extremity and that of the affected extremity was associated with a decrease in complications. One patient who had a snake bite in the right upper extremity developed necrosis and another patient developed compartment syndrome.Conclusion: PI is a rapid, painless, and continuous measurement that provides clinicians with valuable information on both the effectiveness of the antivenom and perfusion of the extremity. Patients with local reactions such as swelling and bruising should be monitored for at least 24 hours, and clinicians should pay attention to the development of compartment syndrome or tissue necrosis in the following hours.