Clonidine-ephedrine combination reduces pain on injection of propofol and blunts hemodynamic stress responses during the induction sequence.
OBJECTIVE
To evaluate the effects of clonidine and ephedrine on propofol-induced pain and on hemodynamic changes during the induction sequence.


METHODS
This was a prospective, randomized, double-blind study.


METHODS
The study was conducted at a university hospital.


METHODS
200 ASA physical status I or II adult patients scheduled for elective surgery.


METHODS
Patients were randomly allocated to one of 4 groups (50 patients per group): clonidine-ephedrine (CE), clonidine-saline (CS), diazepam-ephedrine (DE), and diazepam-saline (DS). Thirty seconds after the administration of ephedrine or saline, propofol 2 mg/kg was infused at a rate of 18.3 mL/min.


METHODS
Patients were asked whether they had pain due to propofol injection. A blinded investigator evaluated the pain score: 0 = no pain, 1 = mild pain, 2 = severe pain without behavioral signs such as grimace or arm withdrawal movement, and 3 = severe pain accompanied by behavioral signs. Mean arterial blood pressure (MAP) and heart rate (HR) were measured at 1-minute intervals from just before the administration of ephedrine or saline to 5 minutes after the tracheal intubation.


RESULTS
Median pain score in CE was significantly lower than those in the other groups (P < 0.0001). Pain scores in CS and DE were significantly lower than that in DS (P < 0.05). Ephedrine increased HR in CE and DE (P < 0.05), but clonidine did not augment the effect. Mean arterial blood pressure before tracheal intubation decreased to comparable values in all groups. After the intubation, mean arterial blood pressure and HR in CE and CS were significantly lower than those in DE and DS (P < 0.05).


CONCLUSIONS
Combination of clonidine and ephedrine effectively reduced propofol-induced pain, but did not prevent propofol-induced hypotension. Clonidine did not augment low dose of ephedrine-induced increase in HR and produced stable hemodynamic condition during the induction sequence.
Ishiyama
Tadahiko
T
Department of Anesthesiology, Faculty of Medicine, University of Yamanashi, Japan. ishiyama@yamanashi.ac.jp
Kashimoto
Satoshi
S
Oguchi
Takeshi
T
Furuya
Atsushi
A
Fukushima
Hisashi
H
Kumazawa
Teruo
T
D000700:Analgesics / Q000494:pharmacology*; D018686:Anesthetics, Intravenous / Q000009:adverse effects*; D003000:Clonidine / Q000494:pharmacology*; D004809:Ephedrine / Q000494:pharmacology*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D015742:Propofol / Q000009:adverse effects*; D011446:Prospective Studies; D013312:Stress, Physiological / Q000188:drug therapy*
D000700:Analgesics; D018686:Anesthetics, Intravenous; D004809:Ephedrine; D003000:Clonidine; D015742:Propofol