Efficacy of morphine versus fentanyl patient-controlled analgesia for postoperative pain management in colorectal surgery.

Introduction: Postoperative pain management is crucial for recovery from surgery. Patient-controlled analgesia (PCA) with morphine and fentanyl are commonly used, but their comparative efficacy remains uncertain. This study aims to evaluate opioid consumption and pain control in patients receiving PCA morphine versus PCA fentanyl after colorectal surgery.

Methodology: A retrospective analysis of adult patients undergoing elective colorectal surgery was conducted. Patients were divided into two groups based on PCA morphine or PCA fentanyl use. Outcomes measured were opioid consumption in morphine equivalents, numerical pain scores expressed as Numerical Rating Scale (NRS), patient demand, and side effects within the first 48 hours postoperatively.

Results: Of 370 patients screened, 152 met the inclusion criteria. No significant differences were found in total opioid consumption (median: 38 vs. 28.5 mg, p = 0.095), patient demand (median: 46.5 vs. 35, p = 0.156), or NRS (median: 4 vs. 3.5, p = 0.348). Side effects were comparable between groups. Subgroup analysis revealed higher opioid consumption and demand in females taking fentanyl compared to morphine. Age was negatively correlated with pain-related outcomes, and smokers showed higher opioid consumption and higher pain scores.

Conclusions: PCA morphine and fentanyl provide similar postoperative pain relief in colorectal surgery patients, with no significant differences in opioid consumption or side effects. Female patients may respond better to morphine, and age and smoking status significantly influence pain management outcomes. Further prospective studies are recommended to better define these findings and inform postoperative pain strategies.