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Correspondence  |   July 2003
Pain Significantly Influences Postoperative Wound Oxygen Tension
Author Notes
  • Carl-Gustav-Carus University Hospital, Dresden, Germany.
Article Information
Correspondence
Correspondence   |   July 2003
Pain Significantly Influences Postoperative Wound Oxygen Tension
Anesthesiology 7 2003, Vol.99, 238. doi:
Anesthesiology 7 2003, Vol.99, 238. doi:
To the Editor:—
Buggy et al.  conducted a very interesting study investigating the influence of epidural or intravenous analgesia on postoperative wound oxygen tension. 1 They found significantly increased values in patients who received epidural analgesic techniques when compared with patients who received intravenous analgesia. In my opinion, the two groups were not comparable, because the patients without neuraxial blockade had significantly higher pain scores. It is known that pain is a major determinant of postoperative subcutaneous oxygen partial pressures. 2 It causes an autonomic response with increased adrenergic nerve activity and plasma-catecholamine concentrations. Hence, according to the presented data it seems unjustified to conclude that epidural techniques improve in general postoperative oxygen wound tension.
The role of neuraxial analgesia to improve postoperative outcome remains to be debated. 3 Randomized trials comparing different perioperative analgesic concepts are often unable to demonstrate the superiority of one of the concepts. This is partially attributable to lack of power and a focus on major morbidities. Buggy et al.  must be congratulated for the aim of their study, but I suggest repeating the investigation while ensuring that patients in both groups receive comparably effective pain treatments. This is not an easy task because patients recovering from surgical interventions often consider pain as normal. They should, therefore, be instructed to use the patient-controlled devices not only to achieve a tolerable level of analgesia but also to aim for an a priori  defined level of analgesia.
References
Buggy DJ, Doherty WL, Hart EM, Pallett EJ: Postoperative wound oxygentension with epidural or intravenous analgesia. A nesthesiology 2002; 97: 952–8Buggy, DJ Doherty, WL Hart, EM Pallett, EJ
Akça O, Melischek M, Scheck T, Hellwagner K, Akiliç CF, Kurz A, Kapral S, Heinz T, Lackner FX, Sessler DI: Postoperative pain and subcutaneous oxygen tension. Lancet 1999; 354: 41–2Akça, O Melischek, M Scheck, T Hellwagner, K Akiliç, CF Kurz, A Kapral, S Heinz, T Lackner, FX Sessler, DI
Kehlet H, Holte K: Effects of postoperative analgesia on surgical outcome. Br J Anaesth 2001; 87: 62–72Kehlet, H Holte, K