Hemodynamic changes in patients with prophylactic Ephedrine before spinal anesthesia

Objective: For several surgical procedures spinal anesthesia is preferred to general anesthesia. However some of its most important effects are reducing blood pressure (Hypotension) and heart rate. In this study, we evaluated the effect of prophylactic intramuscular ephedrine before spinal anesthesia. Methods: This study was conducted on 100 cases in ASA class I (American society of anesthesiologists) between 20-60 years old who had no co-existing disease. They were randomly divided into two groups (Each with 50 cases). The test group received 25mg (0.5ml) intramuscular ephedrine 10-15 minutes before spinal anesthesia and the subjects in control group received 5ml normal saline (0.9%) as placebo. After receiving 500ml Ringer’s solution, spinal anesthesia with 2cc lidocaine 5% was done. Heart rate, systolic and diastolic blood pressure have been measured seven times before ephedrine and placebo injection, before spinal anesthesia and during the procedure at the 2nd, 5th, 15th, 30th and 45th minutes. Then data were rerecorded and compared. Findings: In this study, those who received prophylactic ephedrine had a raised heart rate and blood pressure before spinal anesthesia, but this rise was not more than 10% of the baseline and there was no need to treat their hypotension or reduced heart rate during anesthesia or the operation. But 28% of control group have received ephedrine for treatment of hypotension and 36% of them received atropine to manage bradycardia. After statistical analysis and comparing of these two groups, we have seen that the range of fall of heart rate, systolic and diastolic blood pressure in the study group was narrower than that in control group and their differences were meaningful (P=0.000). Conclusion: The results show that the patients, who have received intramuscular ephedrine before spinal anesthesia, have a rather higher level of hemodynamic stability. Therefore, in patients for whom hemodynamic changes, specially a reduced blood pressure is dangerous such as those with a heart disease, old patients or those undergoing caesarean section using of this method could be useful