Effects of continuous remifentanil administration on intra-operative subcutaneous tissue oxygen tension.

Author(s): Kabon B, Kugener A, Gruenberger T, Niedermayr M, Fleischmann E, Freissmuth M, Kurz A

Affiliation(s): Department of Anaesthesiology and Intensive Care Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria. barbara.kabon@meduniwien.ac.at

Publication date & source: 2007-11, Anaesthesia., 62(11):1101-9.

Publication type: Randomized Controlled Trial; Research Support, Non-U.S. Gov't

Surgical stress response markedly increases sympathetic nerve activity and catecholamine concentrations. This may contribute to peripheral vasoconstriction, reduced wound perfusion and subsequent tissue hypoxia. Opioids are known to depress the hypothalamic-adrenal response to surgery in a dose-dependent manner. We tested the hypothesis that continuous remifentanil administration produces improved subcutaneous tissue oxygen tension compared to fentanyl bolus administration. Forty-six patients undergoing major abdominal surgery were randomly assigned to receive either fentanyl bolus administration or continuous remifentanil infusion. Mean subcutaneous tissue oxygen values over the entire intra-operative period were significantly higher in the remifentanil group, when compared to the fentanyl group: 8 (2) kPa vs 6.7 (1.5) kPa, % CI difference: - 2.3 kPa to - 0.3 kPa, p = 0.013. Continuous intra-operative opioid administration may blunt vasoconstriction caused by surgical stress and adrenergic responses more than an equi-effective anaesthetic regimen based on smaller-dose bolus opioid administration.