Peroperative titration of morphine improves immediate postoperative analgesia after total hip arthroplasty

Purpose: To determine the Influence of peroperative titrated morphine on po stoperative pain control. Methods: Forty patients received general anesthesia for total hip arthropla sty (THA) and were divided into two groups of 20. In the Peroperative group (Perop group;) morphine was titrated at the end of surgery (3 mg iv every 5 or 10 min) in spontaneously breathing intubated patients, until the respi ratory rate (RR) decreased. No morphine was administered to Postop group. I n the Post Anesthesia Care Unit (PACU) patients in Perop and Postop groups received morphine until adequate pain relief VAS less than or equal to 30 m m. Patients used patient-controlled analgesia (PCA) for the next 24 hr. In the PACU, the delay for analgesia, doses of morphine used and incidence of side effects were recorded. Results: In the Perop group, patients received 10.3 +/- 1.3 mg (2-20 mg) as peroperative titration and had achieved adequate analgesia more rapidly th an in the Postop group (42 +/- 7 min vs 76 +/- 7 min); P = 0.0026). Analges ia in the PACU in the Postop group required larger doses of morphine (15.4 +/- 1.5 mg;) than in the Perop group(7.3 +/- 1.3 mg; P = 0.0004). The respi ratory rate decrease during peroperative morphine titration was correlated to the morphine dose needed in the PACU (P = 0.035). Respiratory depression in the PACU was more common in the Postop group than in the Perop group (f ive patients vs nb patient P = 0.017). Conclusion: This study demonstrated that the peroperative administration of morphine can facilitate immediate postoperative pain management.