The effect of prophylactic ephedrine and phenylephrine on hemodynamics in surgical patients in the prone position

Prone positioning during surgery frequently induces hemodynamic instability, posing challenges for perioperative hypertension management. This study compared the effectiveness of prophylactic ephedrine and phenylephrine in maintaining hemodynamic stability in patients placed in the prone position. In this analytic observational study, 38 patients undergoing posterior stabilization surgery were divided into two groups receiving either intravenous ephedrine (0.1 mg/kg) or phenylephrine (1 mcg/kg) prior to positioning. Hemodynamic parameters—systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and heart rate (HR)—were measured at baseline, 5, and 10 minutes after prone positioning. The groups were comparable at baseline. While no statistically significant differences were found in SBP or DBP, the pattern of MAP change differed significantly (Time × Group interaction, p < 0.001), with ephedrine producing a greater and more sustained elevation. Furthermore, ephedrine induced a significant increase in HR at 10 minutes (87.76 ± 8.77 vs. 79.93 ± 4.94 bpm, p = 0.002), whereas phenylephrine maintained a stable HR. In conclusion, both vasopressors prevent hypotension, but their profiles differ: ephedrine provides more sustained pressure support with a chronotropic effect, while phenylephrine offers stable pressure control without tachycardia. The choice between them should be individualized based on the patient’s cardiovascular risk factors, directly informing tailored perioperative hypertension management strategies.