COMPARISON OF 3 MORPHINE REGIMENS IN POSTSURGICAL PATIENTS USING PATIENT-CONTROLLED ANALGESIA

OBJECTIVE: To compare the efficacy and toxicity of three patient-contr olled analgesia (PCA) morphine DESIGN: A prospective, randomized, pilo t study of three PCA morphine regimens: (1) 1 mg with 6-minute lockout (n=10), (2) 2 mg with 12-minute lockout (n=12), and (3) 2 mg with 20- minute lockout (n=12). SETTING: Large teaching institution. PARTICIPAN TS: Thirty-four patients undergoing cholecystectomy or hysterectomy.MA IN OUTCOME MEASURES: Pain scores (0=no pain, 1=mild pain, 2=moderate p ain, 3=severe pain), sedation scores, analgesic consumption, and patie nt attempts (patient activation of PCA device) and injections (doses a ctually delivered) were evaluated using analysis of covariance. Distri bution of pain and sedation scores and adverse effects were assessed u sing Fisher's exact test. RESULTS: Data on 24 patients were evaluable. Six patients withdrew for poor pain control (2 in group 1, 1 in group 2. and 3 in group 3). Three other patients withdrew because of advers e effects and 1 withdrew because of pump problems. Mean morphine consu mption did not differ significantly among the groups. Distribution of pain and sedation scores and the number of patients with nausea were s imilar across treatment groups. The mean injection to attempt ratio wa s significantly smaller in group 3 (0.71 +/- 0.11) compared with group s 1 and 2 (0.9 +/- 0.06 and 0.83 +/- 0.09. respectively; p=0.001 Adver se events occurred similarly among treatment groups. CONCLUSIONS: No s ignificant differences in the efficacy or toxicity of the three morphi ne PCA regimens were identified.