title: Clinical efficacy of oral-transdermal clonidine combinations during the perioperative period.
abstract: In an attempt to maintain stable levels of an alpha 2-adrenergic agonist throughout the perioperative period, two different oral-transdermal clonidine dosage regimens were administered according to a randomized, double-blind, placebo-controlled study in patients undergoing abdominal surgery. We determined the clinical efficacy of a high- and a low-dose clonidine regimen on sedation, hemodynamic parameters, anesthesia, and analgesia. The low-dose clonidine group of patients (n = 14) received a 7-cm2 clonidine transdermal patch (Catapres-TTS #2), which was supplemented with oral doses of clonidine approximately 3 micrograms.kg-1 on the evening prior to surgery and on the morning of surgery. The high-dose clonidine group (n = 14) received a 10.5-cm2 clonidine transdermal patch (Catapres-TTS #3) with oral clonidine approximately 4.5 micrograms.kg-1 at bedtime and 6.0 micrograms.kg-1 on the morning of surgery. Placebo-treated (control) patients received the same occlusive patch without active ingredient and oral placebo tablets at bedtime and on the morning of surgery. Preanesthetic medication included midazolam 50 micrograms.kg-1 intramuscularly (im). Anesthesia was induced with alfentanil 30 micrograms.kg-1 intravenously (iv), thiopental 3 mg.kg-1 iv, and vecuronium 0.1 mg.kg-1 iv, and was maintained with 70% nitrous oxide in oxygen and a continuous infusion of alfentanil 0.5 microgram.kg-1.min-1. Isoflurane was added when the blood pressure exceeded 110% of the patient's prestudy value. For pain relief postoperatively, the patients received morphine, 1-2-mg iv boluses, via a patient-controlled analgesia pump. The low-dose clonidine patient group had mean plasma clonidine concentrations that varied from 1.47 ng.ml-1 (preoperative) to 1.32 ng.ml-1 (postoperative day 2).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Stanford University, California.
authors.forename: I S
authors.initials: IS
authors.lastname: Segal
authors.forename: D J
authors.initials: DJ
authors.lastname: Jarvis
authors.forename: S R
authors.initials: SR
authors.lastname: Duncan
authors.forename: P F
authors.initials: PF
authors.lastname: White
authors.forename: M
authors.initials: M
authors.lastname: Maze
mesh_terms: D000759:Adjuvants, Anesthesia / Q000008:administration & dosage* / Q000097:blood; D000279:Administration, Cutaneous; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D015760:Alfentanil; D000771:Anesthesia, Intravenous; D003000:Clonidine / Q000008:administration & dosage* / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage; D010149:Postoperative Pain / Q000188:drug therapy; D013514:Surgical Procedures, Operative
chemical_list: D000759:Adjuvants, Anesthesia; D006993:Hypnotics and Sedatives; D015760:Alfentanil; D009020:Morphine; D003000:Clonidine