Factors Associated with Hypotension and Bradycardia After Epidural Blockade

Abstract
In order to identify patient-, anesthesia-, and surgery-related factors influencing the probability of hypotension and bradycardia after epidural blockade, an observational study was conducted on 1050 nonpregnant patients. Backward stepwise logistic regression was performed on the variables hypotension (systolic blood pressure < 90 mm Hg) and bradycardia (heart rate < or = 45 bpm). Hypotension and bradycardia occurred in 158 and 24 patients, respectively. The probability of hypotension increased when epidural fentanyl was administered (odds ratio [OR] = 2.18; 95% confidence interval [CI] = 1.16-4.11), with body weight and spread of epidural analgesia, and decreased when a tourniquet was used (OR = 0.01, CI = 0.01-0.02) and bupivacaine instead of carbonated lidocaine was administered (OR = 0.28, CI = 0.14-0.60). Sensitivity and specificity of the model were 89% and 88%, respectively. The probability of bradycardia was less in women (OR = 0.05, CI = 0.01-0.41) and when a tourniquet was used (OR = 0.04, CI = 0.02-0.09). Sensitivity and specificity were 50% and 97%, respectively. In conclusion, our analysis can contribute to identification of patients at high risk to develop hypotension and bradycardia after epidural blockade. If bupivacaine instead of carbonated lidocaine is used and epidural fentanyl is not administered a decrease in the incidence of hypotension may be anticipated.