Abstract Introduction: The incidence of hypotension after administration of anesthesia in the spinal canal in women undergoing abdominal surgical delivery may be about to eighty percent if preventive amplifications, for instance precedent the introduction of additional fluid into the body, propelling the uterus to the left, and vasopressors, have not been considered. Aims: are to analyze the effect of ephedrine and phenylephrine in prophylaxis and treatment of low blood pressure in patients undergoing spinal anesthesia, to figure out the side effects of these drugs and to determine fetal Apgar scores. Method: Fifty five women were randomly designated into two groups to get preventative ephedrine (n=27) or phenylephrine (n=28). Blood pressure, heart rate, frequency of low blood pressure, reactive high blood pressure, heart rate less than 60 BPM, heart rate more than 100 BPM, nausea, vomiting, and Apgar scores were checked out. Results: There were no significant differences in the characteristic data between the groups. The mean (± SD) dose of ephedrine used was 19.81 mg (± 5.46) and phenylephrine was 125.71 µg (± 35.64). Differences in systolic and diastolic pressure were compatible in the two groups. There were significant alterations in the frequency of reactive hypertension episodes (Ephedrine group: 48 (14.5%) vs. Phenylephrine group: 26 (7.7%) P<0.005). There were no divergence in the frequency of bradycardia (Ephedrine group: 3 (11.1%) vs. Phenylephrine group: 6 (21.4%) P>0.301). There were significant differences in the incidence of nausea and vomiting (Ephedrine group: 10 (37%) vs. Phenylephrine group: 3(10.7%); P>0.018). There were no significant diversity in the incidence of hypotension, with an incidence of 18(66.7%) in the Ephedrine group and 17(60.7%) (P<0.646) in the Phenylephrine group. Maternal arrhythmias were more common in the Ephedrine group at 10(37%) than in the Phenylephrine group at 7(25%), but the difference is not significant (P=0.334). Additionally, maternal restlessness was more common in the Ephedrine group: 8(30.8%) than the Phenylephrine group: 3(10.7%), but with an insignificant difference (P=0.068). Diversity in the Apgar score in the 1st and 5th minute was not observed. Number of patients who required rescue dose in the Ephedrine group was 24(88.9%), which was significantly higher than the Phenylephrine group at 20(71.4%), P<0.005). There are significant differences in the number of rescue doses of the two drugs. In the Phenylephrine group there was only one patient (3.6%) that had the rescue dose 3 times, and for the Ephedrine group there were 9 patients (33.3%) that had the rescue dose 3 times each, (P=0.033). Conclusion: This study reinforces the usefulness of phenylephrine for the retainment of blood pressure during administration of anesthesia in the spine for optional surgical delivery.
Keywords: Phenylephrine; Ephedrine; Spinal anesthesia; Maternal hypotension; Cesarean section