title: Postoperative pain trajectories in cardiac surgery patients.
abstract: Poorly controlled postoperative pain is a longstanding and costly problem in medicine. The purposes of this study were to characterize the acute pain trajectories over the first four postoperative days in 83 cardiac surgery patients with a mixed effects model of linear growth to determine whether statistically significant individual differences exist in these pain trajectories, and to compare the quality of measurement by trajectory with conventional pain measurement practices. The data conformed to a linear model that provided slope (rate of change) as a basis for comparing patients. Slopes varied significantly across patients, indicating that the direction and rate of change in pain during the first four days of recovery from surgery differed systematically across individuals. Of the 83 patients, 24 had decreasing pain after surgery, 24 had increasing pain, and the remaining 35 had approximately constant levels of pain over the four postoperative days.
authors.affiliation: Pain Research Center, Department of Anesthesiology, School of Medicine, University of Utah, 615 Arapeen Drive, Suite 200, Salt Lake City, Utah 84108, USA.
authors.forename: C Richard
authors.initials: CR
authors.lastname: Chapman
authors.forename: Ruth
authors.initials: R
authors.lastname: Zaslansky
authors.forename: Gary W
authors.initials: GW
authors.lastname: Donaldson
authors.forename: Amihay
authors.initials: A
authors.lastname: Shinfeld