[Intramuscular and oral clonidine in premedication of the heart surgery patient: hemodynamic effects and interaction with high-dose fentanyl induction].
OBJECTIVE
The aim of the study was to evaluate the efficacy of oral and i.m. clonidine as premedication in reducing the requirements of fentanyl for induction and to analyze its effects on the hemodynamics of patients with ischemic heart disease.


METHODS
University Hospital.


METHODS
The authors considered 30 patients (27 male and 3 female) undergoing CABG. Patients were premedicated 60-90 min before induction of anesthesia and were randomly distributed in three groups: Group A: oral diazepam 0.1 mg x kg -1; Group B: oral diazepam 0.1 mg x k-1 + oral clonidine 5 micrograms x kg-1; Group C: oral oral diazepam 0.1 mg kg-1 + i.m. clonidine 4 micrograms x kg-1. Induction of anesthesia was realized with fentanyl at speed of 500 mcg x min-1 until loss of consciousness was reached (no answer to three consecutive questions).


METHODS
Hemodynamic data were recorded at TO(baseline), T1(induction of anesthesia), T2(3 min after intubation), T3(3 min. after skin incision). Results were analyzed by utilizing the average comparison Student "t" test and paired "t" test. A value of p < 0.05 was regarded as statistically significant.


RESULTS
In groups B and C the inductive dose of fentanyl was much lower (p < 0.001) compared to control group (B = 19.23 +/- 3.57 micrograms x kg-1; C = 19.92 +/- 4.15 micrograms x kg-1; A = 28.39 +/- 6.4 micrograms x kg-1). This difference remained statistically significant (p < 0.001) also at T2 and T3 (T1: A = 42.79 +/- 3.21 mcg x kg-1; B = 29.07 +/- 6.18 micrograms x kg-1; C = 29.84 +/- 5.46 micrograms x kg-1; T2: A = 57.28 +/- 5.32 micrograms x kg-1; B = 43.22 +/- 3.87 micrograms x kg-1; C = 43.48 +/- 4.25 micrograms x kg-1). Considering the hemodynamic data, we report the heart rate in group B increased at T2 (p < 0.01), and systolic artery pressure raised in groups A (p < 0.05) and C (p < 0.01) at T2. Compared to baseline cardiac index showed a decrement at T3 in all groups of patients (p < 0.05). Systemic vascular resistance increased in all groups at T3 compared to baseline (p < 0.05).


CONCLUSIONS
Clonidine proved to be useful to reduce narcotic requirements and to provide hemodynamic stability.
Menichetti
A
A
Università degli Studi di Roma La Sapienza.
Tritapepe
L
L
Marino
P
P
Cogliati
A
A
Di Giovanni
C
C
Pacilli
M
M
Arzilla
R
R
Di Marco
P
P
D000284:Administration, Oral; D006348:Cardiac Surgical Procedures; D003000:Clonidine / Q000008:administration & dosage*; D004347:Drug Interactions; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage*; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D011229:Preanesthetic Medication
D003000:Clonidine; D005283:Fentanyl