Immediate postoperative pain in orthopedic patients is more intense and requires more analgesia than in post-laparotomy patients

Abstract

Objective: To compare the immediate postoperative pain intensity between orthopedic and general surgery patients and evaluate the extent of severe pain in each group.

Design: Observational, open-label study.

Setting: Post-anesthesia care unit (PACU) in a tertiary, university-affiliated hospital.

Patients: Patients undergoing orthopedic surgery or laparotomy under general anesthesia over a one-year period.

Interventions: Follow-up of patient self-rated pain visual analog scale (VAS, 0-10), and observation of the efficacy of the routine analgesic protocol of morphine, ketamine, and diclofenac administration in the PACU.

Outcome measures: We followed pain scores and sorted patients according to morphine requirements during the PACU immediate postoperative stay. Patients whose pain was controlled with ≤120 µg/kg intravenous morphine were considered pain-controllable. Where this amount was insufficient to control pain (VAS ≥5/10), patients were categorized as suffering from severe pain. They were further treated with repeated doses of 1 mg morphine plus 350 µg/kg ketamine (M+K) and eventually diclofenac. PACU follow-up lasted 3 hours.

Results: The overall rate of immediate severe postoperative pain within the entire cohort (3,460 patients) was 9.4%: 123 (6.6%) of laparotomy patients and 202 (12.7%) of orthopedic patients. Pain in the laparotomy patients identified as suffering from severe pain was controlled with 1.21±0.45 doses of M+K compared with 1.37±0.62 (P<0.0001) in the orthopedic counterparts. One-fifth of these laparotomy patients demanded more than one injection of M+K compared with one-third of the orthopedic subgroup (P=0.045). Twenty-seven orthopedic vs nine surgical patients (P=0.036) required diclofenac.

Conclusions: More orthopedic than laparotomy patients suffered from severe immediate postoperative pain. They required more analgesia than that dictated by existing PACU analgesia protocols. Ketamine and morphine co-administration proved effective in controlling severe postoperative pain after each type of surgery.