A comparative study of three different doses of levobupivacaine for spinal anaesthesia in cesarean section

The aim of this study was to compare the motor and sensorial block and the hemodynamic effects of three different low doses of intrathecally administered % 0.5 levobupivacaine combined with 25 µg fentanyl for cesarean section.Ninety women scheduled for cesarean section were randomly divided into 3 groups of patients who received a spinal injection of either 6.5 mg (group 1) , 7.5 mg (group 2) or 8.5 mg (group 3) plaine levobupivacaine 0.5 % all combined with 25 µg fentanyl. After intrathecal injection of the study drug using the combined spinal epidural technique, sensorial and motor block level as well as blood pressure and heart rate were recorded every 2 minutes for the first 20 minutes and every 5 minutes thereafter until 45th minute. When sensorial block didn?t reach T4 before surgical incision or when patients experienced intraoperative pain, rescue local anaesthetic was administered through the epidural catheter.When compared with the baseline values, in each group there was a statistically significant fall in blood pressure and heart rate (p<0.05). There was however no difference in the frequency of hypotension and bradycardia or administration of ephedrine and atropin between the groups (p>0.05). Except one patient in group 1 all patients reached sensorial block of T4. In the same group 6 patients experienced intraoperative pain and received rescue analgesia via the epidural catheter (p<0.05). Twelve patients in group 1, 3 patients in group 2 and 4 patients in group 3 didn?t develope any motor block. This and the regression to Bromage 0 was also different between the groups (p<0.05). There was no difference according to side effects.Based on our data, spinal anaesthesia with 6.5 mg 0.5 % levobupivacaine combined with 25 µg fentanyl didn?t offer efficient anaesthesia for cesarean section. However 7.5 mg and 8.5 mg levobupivacaine 0.5 % combined with fentanyl 25 µg were both equal in regard to intraoperative pain and motor block and as a lower dosis 7.5 mg may be prefered.Key words: levobupivacaine, fentanyl, cesarean sectio, spinal anaesthesia