Outcome measurement methodology
Professor Henrik Kehlet
Professor of perioperative therapy and Head of Section of Surgical Pathophysiology,
Rigshospitalet, Copenhagen University, Denmark
Optimized perioperative pain treatment has besides its humanitarian value been hypothesized to
improve early perioperative organ dysfunctions and morbidity as well as to have a potential effect
on long-term persistent pain problems. Although these hypotheses are still valid, the literature
unfortunately had several inadequates in design of outcome studies limiting interpretation. This
applies to many interventions such like the effect of regional anesthetic techniques and outcome,
including the Master trial, the use of minimal invasive surgery techniques to improve outcome, the
effect of preemptive or preventive analgesia on early postoperative pain and on persistent
postsurgical pain. The reason hereto is that such unimodal interventional studies have been
simplified in contrast to the multimodality problem of perioperative outcome. Furthermore, most
studies have had limited assessment of the pain-related functional consequences.
In summary, there continues to be a design problem and development of procedure-specific painrelated outcomes for both acute and persistent postsurgical pain is urgently required.
References
Kehlet H, Dahl JB. Anaesthesia, surgery, and challenges in postoperative recovery. Lancet 2003;
362:1921-1928.
McCarthy M, Jr., Jonasson O, Chang CH, Pickard AS, Giobbie-Hurder A, Gibbs J et al.
Assessment of patient functional status after surgery. J Am Coll Surg 2005; 201:171-178.
Franneby U, Gunnarsson U, Andersson M, Heuman R, Nordin P, Nyren O et al. Validation of an
Inguinal Pain Questionnaire for assessment of chronic pain after groin hernia repair. Br J
Surg 2008; 95:488-493.
Kehlet H, Wilmore DW. Evidence-based surgical care and the evolution of fast-track surgery.
Ann Surg 2008; 248:189-198.
White PF, Kehlet H. Improving postoperative pain management: what are the unresolved issues?
Anesthesiology 2010; 112:220-225.
Srikandarajah S, Gilron I. Systematic review of movement-evoked pain versus pain at rest in
postsurgical clinical trials and meta-analyses: a fundamental distinction requiring
standardized measurement. Pain 2011; 152:1734-1739.
Kehlet H, Dahl JB. Assessment of postoperative pain--need for action! Pain 2011; 152:16991700.
Wildgaard K, Ravn J, Nikolajsen L, Jakobsen E, Jensen TS, Kehlet H. Consequences of
persistent pain after lung cancer surgery: a nationwide questionnaire study. Acta
Anaesthesiol Scand 2011; 55:60-68.