title: Epinephrine decreases postoperative requirements for continuous thoracic epidural fentanyl infusions.
abstract: Epidural thoracic fentanyl infusions provide effective preoperative analgesia after thoracotomy; however, side effects can limit the effectiveness of this technique. This study evaluates epinephrine as an adjunct to continuous thoracic epidural fentanyl infusions after thoracotomy. Thirty-eight patients were studied in a prospective, randomized, double-blind trial comparing fentanyl alone to fentanyl with epinephrine 1:300,000. Epidural infusion rates were titrated to equivalent pain relief using a visual analog scale. With the addition of epinephrine, there was a significant reduction in fentanyl requirements (0.82 +/- 0.07 vs 1.19 +/- 0.11 micrograms.kg-1.h-1, P = 0.005, repeated-measures analysis of variance) and in plasma fentanyl concentrations (steady state: 0.91 +/- 0.13 vs 1.65 +/- 0.23 ng/mL, P = 0.007, repeated-measures analysis of variance). There were no differences in pain scores, side effects, spirometry, patient satisfaction scores, or hemodynamic variables. This study demonstrates that adding epinephrine 1:300,000 to continuous thoracic epidural infusions decreases fentanyl requirements titrated for effective analgesia. The reduction in fentanyl requirements was associated with reduced fentanyl plasma concentrations.
authors.affiliation: Department of Anesthesia and Surgery, University of Manitoba, Winnipeg, Canada.
authors.forename: C M
authors.initials: CM
authors.lastname: Baron
authors.forename: S E
authors.initials: SE
authors.lastname: Kowalski
authors.forename: R
authors.initials: R
authors.lastname: Greengrass
authors.forename: T A
authors.initials: TA
authors.lastname: Horan
authors.forename: H W
authors.initials: HW
authors.lastname: Unruh
authors.forename: C L
authors.initials: CL
authors.lastname: Baron
mesh_terms: D015360:Analgesia, Epidural / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000008:administration & dosage*; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage* / Q000097:blood; D005541:Forced Expiratory Volume; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care / Q000379:methods*; D011446:Prospective Studies; D013903:Thoracic Surgery / Q000379:methods*
chemical_list: D005283:Fentanyl; D004837:Epinephrine