Risk factors for intraoperative variatons in blood pressure and cardiac dysrhythmia during thyroid surgery

Introduction/Objective. Intraoperative variations in blood pressure and/or cardiac dysrhythmias (IOVBP/CD) represent one of the most common causes of morbidity and mortality in surgical patients. The aim of the study was to determine the incidence and risk factors for IOVBP/CD in thyroid surgery patients with comorbidities. Methods. The study included 1252 euthyroid patients with ASA 2 and ASA 3 status who underwent thyroid surgery. The following risk factors were examined: gender, age, body mass index (BMI), ASA status, admission diagnoses, type of operation, duration of surgery, time under general anesthesia, difficult intubation of trachea and coexisting diseases: hypertension, cardiomyopathy (CMP), cardiac arrhythmias, angina pectoris, diabetes mellitus (DM), kidney disease. Following intraoperative events were recorded: hypertension, severe hypertension, hypotension and cardiac arrhythmias. We used Pearson chi-square test, univariate and multivariate logistic regression for statistical analysis. Results. The majority of patients were female (86.3%). In 903 (72.1%) patients IOVBP/CD were detected. The most common problem was intraoperative hypertension 61.4%. Eight risk factors for IOVBP/CD were registered by univariate analysis: advanced age, ASA 3 status, BMI>25kg/m2, duration of surgery, time under general anaesthesia, hypertension and cardiomyopathy as coexisting disease. The multivariate regression model identified three independent predictors for IOVBP/CD: age, hypertension and cardiomyopathy. Conclusion. IOVBP/CDs are common in thyroid surgery. The most common is intraoperative hypertension. Older age, hypertension and cardiomyopathy as a coexisting disease are independent risk factors for IOVBP/CD.