Analgesic and hemodynamic effects of epidural clonidine, clonidine/morphine, and morphine after pancreatic surgery--a double-blind study

Anesth Analg. 1995 May;80(5):869-74. doi: 10.1097/00000539-199505000-00003.

Abstract

This study characterizes analgesia an hemodynamics after epidural clonidine 8 micrograms/kg (Group C) or clonidine 4 micrograms/kg+morphine 2 mg (Group CM) in comparison to epidural morphine 50 micrograms/kg (Group M). Forty-five patients scheduled for pancreatectomy in combined general/epidural anesthesia were studied. The study drugs were administered 75 min postoperatively and for 10 h pain intensity (visual analog scale [VAS]), heart rate (HR), mean arterial pressure (MAP), and cardiac output (CO) were measured; filling pressures were kept > 5 mm Hg. Adequate analgesia could be achieved within 1 h in all patients of Groups C and CM, but only in six patients of Group M (P < 0.001). Quality of analgesia was comparable in all groups (VAS reduction 82% +/- 20%, mean +/- SD) but duration of analgesic action was longer in Groups CM (586 +/- 217 min) and M (775 +/- 378 min) compared to Group C (336 +/- 119 min) (P < 0.001). In Group M, no hemodynamic alterations occurred. In Groups C and CM, HR, CO, and MAP were reduced significantly compared to baseline within the first 15-90 min, while stroke volume and systemic vascular resistance remained stable. We conclude, that hemodynamic alteration after epidural clonidine under conditions of stable filling pressures is caused mainly by a decrease in HR. It is not an effect of analgesia but of the intrinsic antihypertensive action of clonidine.

Publication types

  • Clinical Trial
  • Comparative Study
  • Controlled Clinical Trial

MeSH terms

  • Analgesia, Epidural*
  • Clonidine* / administration & dosage
  • Clonidine* / pharmacology
  • Double-Blind Method
  • Female
  • Hemodynamics / drug effects*
  • Humans
  • Male
  • Middle Aged
  • Morphine* / administration & dosage
  • Morphine* / pharmacology
  • Pain Measurement
  • Pain, Postoperative / therapy*
  • Pancreatectomy*
  • Prospective Studies

Substances

  • Morphine
  • Clonidine