Maternal and Neonatal Effects of Thiopental Sodium-Enflurane-N2O and Propofol-N2O Anesthesia for Cesarean Section / 대한마취과학회지

BACKGROUND: In anesthesia for cesarean section, thiopental sodium is regarded as the standard induction agent. Propofol, 2,6 di-isopropyl phenol, is a relatively new intravenous anesthetic agent and has been used for induction and maintenance of general anesthesia or total intravenous anesthesia. Propofol has properties which suggest that it might be useful alternative to thiopental. METHODS: Forty patients (ASA physical status 1,2) scheduled for cesarean section were randomized to either propofol (n=20) or thiopental group (n=20). In thiopental group anesthesia was induced with thiopental 4-5 mg/kg intravenously and maintained by inhalation of enflurane and nitrous oxide. In propofol group anesthesia was induced with propofol 2 mg/kg intravenously and maintained by continuous infusion of propofol 6-10 mg/kg/hr and inhalation of nitrous oxide. RESULTS: Systolic and mean arterial pressure were increased significantly in both groups at 1 min after intubation, but degree of increase were less in propofol group. There was no significant difference in diastolic pressure in both groups. Heart rate was increased significantly in both groups at afterinduction, but degree of increase were less in propofol group. The Apgar scores of the neonates and blood gas analyses of umbilical vein were not significantly different in both groups. Maternal recovery from anesthesia was quicker in propofol group. CONCLUSIONS: A propofol infusion coupled with nitrous oxide was proved to be clinically satisfactory anesthesia for cesarean section with no adverse effect on both mother and fetus. Conclusively, propofol would be an excellant alternative to thiopental sodium and inhalation anesthetic in general anesthesia for cesarean section.

Analgesic Effect with Epidural Bupivacaine and Verapamil in Lower Abdominal Surgery / 대한마취과학회지

BACKGROUND: Activation of N-methyl-D-aspartic acid (NMDA) receptors leads to Ca++ entry into the cell and initiates a series of central sensitization such as wind up and longterm potentiation in the spinal cord. Therefore, it can be postulated that the central sensitization would be prevented by blocking Ca++ entry with verapamil. In this double-blind study, we administered lumbar epidural bupivacaine or bupivacaine plus verapamil to verify whether preoperative epidural anesthesia can preempt postoperative pain and to investigate the possible role of calcium channel blocker, verapamil, in the central sensitization. METHODS: Sixty patients (ASA class I-II) scheduled for lower abdominal surgery were randomly assigned to one of three groups of equal size. Group 1 (PR) is preincisional epidural bupivacaine group. Group 2 (PO) is postincisional epidural bupivacaine group. Group 3 (PRV) is preincisional epidural bupivacaine and verapamil group. Visual analogue pain and mood scores, Prince Henry Scores, sedation scores, cumulative PCA (patient controlled analgesia) morphine consumptions, and the incidence of side effects were assessed at 2, 6, 12, 24, 48 hours after operation. RESULTS: Cumulative PCA morphine consumptions in PRV group was significantly lower than in PR and PO group at 24, 48 hours after surgery. The incidence of side effects had no difference among three groups. CONCLUSIONS: Preoperative epidural anesthesia with 10ml of bupivacaine would be insufficient to preempt postoperative pain in lower abdominal surgery. However, addition of verapamil to preoperative epidural bupivacaine would decrease postoperative pain possibly by preventing the establishment of central sensitization.

Changes of N2O Concentration in the Intestinal Lumen and Bowel Distension During General Endotracheal Anesthesia / 대한마취과학회지

During the course of anesthetic administration, appreciate volume of nitrous oxide can move into closed gas spaces. The use of nitrous oxide during abdominal surgery may cause distension of the intestine and make difficulty in operating procedure. We studied 29 patients undergoing elective colorectal surgery and they were classified into two groups -N2O group and Air group, N2O group was administered with air-oxygen-enflurane before peritoneal opening and administered with N2O- oxygen-enflurane after peritoneal opening. Air group was administered with air-oxygen-enflurane throughout the surgery. We measured N2O concentration in the terminal ileum, the degree of distension in the small and large intestine during anesthesia, and the time of postoperative flatulence and feces passage. The N2O concentration in the intestine increased throughout the time course in N2O group. The distension score of the small and large bowel had a tendency to increase in N2O group. There were no significant differences between the two groups in postoperative bowel motility. These results suggest that a long-term N2O administration in patients undergoing colorectal surgery may interfere surgical conditions of the intestine because of the bowel distension.

Comparison of an Ephedrine Injection with Crystalloid Infusion for Prevention of Hypotension During Spinal Anesthesia in Geriatric Patients / 대한마취과학회지

This study was designed to compare the efficacy of an ephedrine intramuscular injection with crystalloidadministration for the prevention of hypotension during spinal anesthesia in geriatric patients undergoing hip fracture surgery. Twenty-seven ASA II patients scheduled for the .arthroplasty of femoral neck fracture under spinal anesthesia were randomly allocated to receive either 15 ml/kg of Ringer's lactated solution (crystalloid group) or an ephedrine intramuscular injection (ephedrine group). Spinal anesthesia was performed in a lateral decubitus position. According to the patient's height, 10-12 mg of hyperbaric 0,5% tetracaine was injected through a 23-25 gauge spinal needle at the L3-4 or L4-5 interspace. Patients in crystalloid group received Ringer's lactated solution 15 mVkg, over 20 minutes before spinal anesthesia. Patients in the ephedrine group were injectede 30 mg of ephedrine I.M immediately after spinal anesthesia. The incidence of hypotension was 8/12 (66%) in the crystalloid group and 6/15 (40%) in the ephedrine group (p<0.01). There was no significant difference between the groups in the level of anesthesia or heart rate, and hypertension did not occur in either group. The result of this study suggests that the intramuscular injection of ephedrine may be more effective than crystalloid infusion for the prophylaxis of hypotension associated with spinal anesthesia in geriatric patients.

Comparison of an Ephedrine Injection with Crystalloid Infusion for Prevention of Hypotension During Spinal Anesthesia in Geriatric Patients / 대한마취과학회지

This study was designed to compare the efficacy of an ephedrine intramuscular injection with crystalloidadministration for the prevention of hypotension during spinal anesthesia in geriatric patients undergoing hip fracture surgery. Twenty-seven ASA II patients scheduled for the .arthroplasty of femoral neck fracture under spinal anesthesia were randomly allocated to receive either 15 ml/kg of Ringer's lactated solution (crystalloid group) or an ephedrine intramuscular injection (ephedrine group). Spinal anesthesia was performed in a lateral decubitus position. According to the patient's height, 10-12 mg of hyperbaric 0,5% tetracaine was injected through a 23-25 gauge spinal needle at the L3-4 or L4-5 interspace. Patients in crystalloid group received Ringer's lactated solution 15 mVkg, over 20 minutes before spinal anesthesia. Patients in the ephedrine group were injectede 30 mg of ephedrine I.M immediately after spinal anesthesia. The incidence of hypotension was 8/12 (66%) in the crystalloid group and 6/15 (40%) in the ephedrine group (p<0.01). There was no significant difference between the groups in the level of anesthesia or heart rate, and hypertension did not occur in either group. The result of this study suggests that the intramuscular injection of ephedrine may be more effective than crystalloid infusion for the prophylaxis of hypotension associated with spinal anesthesia in geriatric patients.