Laparoscopic surgery may be associated with severe pain and high analgesia requirements in the immediate postoperative period

Abstract

Objective: To assess the immediate (0-4 hours) postoperative pain level in patients after laparoscopy and laparotomy whose analgesic requirement in the Post-Anesthesia Care Unit (PACU) exceeds standard morphine therapy.

Background data: Clinical observation has raised the suspicion that laparoscopic surgery may be associated with more intense immediate postoperative pain than expected.

Methods: This prospective study assessed the 24-hour pain intensity and analgesia requirements in patients who underwent similar abdominal surgery via laparoscopy or laparotomy under standardized general anesthesia and whose pain in the PACU was resistant to 120 microg/kg intravenous morphine.

Results: Of 145 sampled PACU patients, 67 were in pain (> or =6 of 10 VAS) within a 30-minute postoperative period. They were then given up to 4 intravenous boluses of 15 microg/kg morphine + 250 microg/kg ketamine. The pain VAS of 36 laparotomy patients was 4.14 +/- 2.14 (SD) and 1.39 +/- 0.55 at 10 and 120 minutes, respectively, after 1.33 +/- 0.59 doses of morphine + ketamine; the pain VAS of 31 laparoscopy patient was 6.06 +/- 1.75 and 2.81 +/- 1.14, respectively (P < 0.0005) following 2.0 +/- 0.53 doses (P = 0.0005). Diclofenac 75 mg intramuscular usage was similar (P = 0.43) between the groups up to 9 hours after surgery but was higher in the laparotomy group by 24 hours (P = 0.01). Pain scores at 24 hours after surgery were lower for the laparoscopy patients (3.01 +/- 0.87) compared with their laparotomy counterparts (4.45 +/- 0.98, P < 0.001).

Conclusions: Among patients after abdominal surgery with severe immediate (0-4 hours) postoperative pain, laparoscopic patients are a significant (46%) proportion, and their pain is more intense, requiring more analgesics than painful patients (54%) do after laparotomy. By 24 hours, the former are in less pain than the latter.

Figures

FIGURE 1. A, Self-rated (by 0–10 VAS) pain intensity (median, ranges, minimum and maximum values, and 25–75 percentiles). Dotted boxes are laparotomy-collected, and solid line boxes represent laparoscopy patient data. *P = 0.001 (by Mann-Whitney U test) except for times 0 and 9 hours. B, Self-rated (by 0–10 VAS) 4-hour cumulative pain intensity (median, ranges, minimum and maximum values, and 25–75 percentiles). *P = 0.009 (by Mann-Whitney U test).

FIGURE 2. Self-rated levels (by 1–10 VAS) of wakefulness (lower half) and feeling of well-being (upper half) (mean ± SD). *P = 0.03 between the groups (by ANOVA) between 20 and 60 minutes (wakefulness), and from 30 minutes on (feeling), respectively. **P < 0.01 between the groups (by Mann-Whitney U test).

FIGURE 3. Nurse-assessed respiratory rate (upper half) and fingertip-derived arterial blood saturation on air (lower half) (mean ± SD). *P = 0.04, †P = 0.02 between groups (by ANOVA) within the first 20 minutes (respiration) and between 5 and 25 minutes (saturation), respectively.