Comparing with the simple general anesthesia, the combine thoracic epidural and general anesthesia generally provide with more improved regional endocardial perfusion, reduced myocardial oxygen consumption, eventually reduced postoperative
morbidity and
mortality.
Patients undergoing thoracotomy have severe pain and related cardio-respiratory impairment postoperatively, so large amount of the analgesics are usually administered systemically.
Recently, the method using using epidural injection of the local anesthetics and/or analgesics is prefered during and after the operation because of its excellent analgesic action and advantage of lowering the need for anesthetics and systemic
analgesics but has remaining problems such as cardiopulmonary and CNS depression and reduced motor function and so on.
So, in an attempt to reduce the untoward effects of epidural injection, we planned to evaluate the validity of the mixing local anesthetic, bupivacaine, and narcotic analgesic, fentanyl, in a given concentration and infusion rate and randomized
70
patients undergoing thoracotomy into 4 groups.
Group A(n=20): Intermittent intramuscular injection of nalbuphine hydrochloride in a dose of 0.2mg/kg
Group B(n=15): Continuous epidural infusion of fentanyl citrate, 2~5ml/hr of 5 mcg/ml solution
Group C(n=15): Continuous epidural infusion of bupivacaine hydrochloride, 2~5ml/hr of 0.15% solution
Group D(n=20): Continuous epidural infusion of mixtures of fentanyl and bupivacaine, 2~5ml/hr of same concentrations
We observed the visual analogue pain scale perioperatively and measured the hemodynamic parameters such as cardiac output, cardiac index, systemic vascular resistance, stroke volume, mean arterial pressure and heart rate.
@ES The results were as follows:
@EN 1) The postoperative analgesic outcome was best in group D as compared with other groups.
2) The cardiac output decreased postoperatively in group A, B and C while group D showed an increase but there was no statistical significance.
3) The cardiac index decreased significantly in group B and showed a trend of decreasing in group C, increasing in group D, and no change in group A.
4) The stroke volume decreased postoperatively in group A and B but the significance was only in group A.
5) The systemic vascular resistance showed significant postoperative increase in group B.
6) The mean arterial pressure decreased in group D and increased in other groups.
7) The heart rate increased during and immediate after the operation in group B.
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