Effect of Intrathecal Clonidine in Hyperbaric Bupivacaine Spinal Anesthesia / 대한마취과학회지

BACKGROUND: Vasoconstrictors have been used as an adjunct to local anesthetics to prolong the duration of spinal anesthesia. Recently, clonidine, an 2-receptor agonist has been shown to prolong the duration of spinal anesthesia following intrathecal administration. Bupivacaine has been used for spinal anesthesia and compared with tetracaine in recent studies. We have undertaken this study to further evaluate the effect of clonidine in hyperbaric 0.5% bupivacaine spinal anesthesia. METHODS: Thirty patients who were scheduled for lower limb or urologic operation were divided into 2 groups: Group A (hyperbaric bupivacaine 13 mg, 2.6 ml + N/S 1 ml), Group B (hyperbaric bupivacaine 13 mg, 2.6 ml + clonidine 150 g, 1 ml). We used standardized techniques and injected above drugs to group A and B intrathecally for spinal anesthesia. We investigated the onset and the duration of spinal anesthesia along with hemodynamic changes (blood pressure and heart rate) in patients. RESULTS: There were no significant differences in the onset of spinal anesthesia and hemodynamic changes between two groups. The time taken to recover from the nerve block was more prolonged in the group B (touch 225, pain 262, foot dorsiflexion 271, knee flexion 290 minutes) than group A (touch 154, pain 188, foot dorsiflexion 198, knee flexion 216 minutes). There were no significant differences in sedation, and in experiencing dry mouth and other side effects between two groups. CONCLUSION: Intrathecal clonidine 150 g has been proved to prolong the duration of hyperbaric 0.5% bupivacaine spinal anesthesia without neurotoxicity or dangerous hemodynamic depression. Therefore, clonidine can be used as an effective adjunct in hyperbaric bupivacaine spinal anesthesia.

Influence of Clonidine on the Postoperative Analgesic Effect of Epidural Bupivacaine and Fentanyl / 대한마취과학회지

BACKGROUND: Epidural clonidine reduces pain after surgery. The aim of this study was to evaluate the effect of adding low-dose clonidine to continuous epidural local anesthetics and fentanyl on pam relief. METHODS: 100 patients scheduled for gynecologic low abdominal surgery were investigated. All patients were given 10cc of 0.25% bupivacaine with fentanyl 100 ug through epidural catheter. Group I was infused with combined 0.15% bupivacaine and fentanyl 5 ug/ml at a rate of 2cc/hr. Group II was infused with combined 0.15% bupivacaine and fentanyl 5 ug/ml and 150 ug of clonidine at a rate of 2cc/hr. Pain was assessed on a visual analogue pain scale for 2 postoperative days. Changes in blood pressure, heart rate, and incidence of side effects were observed. RESULTS: VAS observed 20min, 1hr, 1day, 2days after operation were significantly lower in Group II than Group I . Blood pressure and heart rates were significantly changed in Group II but not in Group I for 2 hours after epidural injection. The incidence of side effects was similar between Group I and Group II. CONCLUSIONS: Continuous low-dose epidural clonidine infusion reduces blood pressure and heatt rates significantly but enhances postoperative analgesic effect of combined epidural bupivacaine and fentanyl without increased side effects.

Epidural Morphine-Bupivacaine versus Fentanyl-Bupivacaine for postoperative pain control / 대한마취과학회지

The fallowing study was performed in 100 patients undergoing gynecologic lower abdominal surgery. Analgesic efficacy, changes in arterial blood pressure and heart rate, and incidence of side effect were observed after epidural injection of the drugs. The patients were devided into two groups (N=50). Group I was given a bolus dose of 1 mg morphine in 10 ml of 0.25% bupivacaine followed by continuous epidural infusion of morphine 0.05 mg/ml in 0.15% bupivacaine at 2 ml/hr. Group II was given a bolus dose of 100 ug fentanyl in 10 ml of 0.25% bupivacaine followed by continuous epidural infusion of fentanyl 5 ug/ml in 0.15% bupivacaine at 2 ml/hr. The results were as follows. 1) The pain score (visual analogue pain scale) measured at postoperation 1 hr was significantly decreased in Group II (1.51+/-1.0) compared to group I (2.20+/-1.1). Percentage of patients needed supplemental analgesics within postoperation 20 min was significantly lower in Group II (4%) than Group I (16%). 2) The cardiovascular changes for 2 hrs after epidutal injection were not occurred significant in both groups. 3) The incidence of nausea or vomiting was significantly lower in Group II (8%) than Group I (28%). Pruritus occurred also significantly less often in Group lI (6%) than group I (30%). Urinary retention and respiratory depression were not observed.