Nitrous oxide increases the incidence of bowel distension in patients undergoing elective colon resection.

Abstract

BACKGROUND:

Nitrous oxide rapidly inflates gas-filled spaces such as the intestines; but whether the resulting bowel distension is clinically important remains unclear. We therefore tested the hypothesis that nitrous oxide produces clinically important bowel distension.

METHODS:

Patients scheduled for colon resection were anesthetized with isoflurane and 35% oxygen and randomly assigned to 65% nitrous oxide (n = 175) or 65% nitrogen in air (n = 169). At the end of surgery, blinded surgeons rated the degree of bowel distension as none, mild, moderate, or severe. Patients reported pain, and nausea and vomiting (PONV) 2 h after surgery. Data are reported as means (SD). P < 0.05 was statistically significant.

RESULTS:

Morphometric and demographic data were similar in the groups. The duration of surgery was 3.0 (1.2) h in the nitrous oxide group and 3.4 (1.5) h in the air group (P = 0.017). Postoperative self-reported pain scores (visual analog scale, 0-100 mm) were greater in the nitrous oxide group (43 [30] mm) than in the air group (35 [31] mm, P = 0.018). Although the incidence of PONV was similar in the groups, VAS scores for nausea were significantly greater in the nitrous oxide group (P = 0.040). Moderate-to-severe bowel distension was observed in 23% of nitrous oxide patients, but in only 9% of patients in the air group (P < 0.001). The number-needed-to-harm for moderate or severe bowel distension from nitrous oxide was thus seven.

CONCLUSIONS:

Our results suggest that avoiding nitrous oxide administration during prolonged bowel operations will minimize bowel distension and possibly reduce postoperative pain related to it.

• Authors: O Akca, R Lenhardt, E Fleischmann, T Treschan, R Greif, R Fleischhackl, O Kimberger, A Kurz, D I Sessler
• Journal: Acta anaesthesiologica Scandinavica (Acta Anaesthesiol Scand) Vol. 48 Issue 7 Pg. 894-8 (Aug 2004) ISSN: 0001-5172 [Print] England
• PMID: 15242436 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Nitrous Oxide

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Colon (surgery)
• Female
• Humans
• Incidence
• Intestinal Diseases (chemically induced, epidemiology)
• Male
• Middle Aged
• Nitrous Oxide (adverse effects)
• Postoperative Nausea and Vomiting (epidemiology)
• Pressure