COMPARISON OF HAEMODYNAMIC PROFILE AFTER SPINAL ANAESTHESIA IN PATIENTS ON REGULAR TREATMENT WITH CALCIUM CHANNEL BLOCKERS AND beta BLOCKERS

BACKGROUND Hypertensive patients develop wide swings in blood pressure intraoperatively, especially after spinal anaesthesia. Long term antihypertensive agents can modify this effect by controlling blood pressure. This study was undertaken to evaluate the haemodynamic effect in hypertensive patients on regular treatment with calcium channel blockers and beta-blockers who are undergoing elective surgery under spinal anaesthesia and compared with normotensives. AIMS To study the intraoperative changes of blood pressure and heart rate in patients on calcium channel blockers and beta-blockers undergoing surgery under spinal anaesthesia and to compare the data with normotensive patients. MATERIALS AND METHODS 90 patients were included in the study; 30 patients were normotensives (Group N) and 30 patients were hypertensives who were regularly on calcium channel blockers (Group C) and 30 patients on beta-blockers (Group B). Both the groups continued the drug on the day of surgery. The baseline blood pressure and heart rate were recorded. After spinal anaesthesia, the blood pressure and heart rate were noted at 2 min, 4 min, 6 min, 8 min, 10 min, 15 min and thereafter with 5 minutes interval till the end of the procedure. STATISTICAL ANALYSIS Baseline data was analysed using descriptive statistics. Intragroup variation in parameters analysed by one way ANOVA and within the different time intervals by post-hoc test. Intergroup comparison by unpaired 'T' test. P value <0.05 considered statistically significant. RESULTS The hypotension was evident in Group C compared to other groups, but bradycardia (heart rate <60) more seen in Group B and were statistically significant (P<0.001). The usage of rescue medication was more in study group and was statistically significant (P<0.002). CONCLUSION Incidence of hypotension was more with patients on calcium channel blockers and required vasopressors and fluids, but incidence of bradycardia was seen more in patients on beta blockers who needed atropine. Anaesthesiologists should anticipate and be adequately prepared for any untoward consequences.