How Long Should a Patient Stay in Lateral Position for Unilateral Spinal Anesthesia with Hyperbaric Bupivacaine? / 대한마취과학회지

BACKGROUND: In searching for a differential spinal block between dependent and nondependent sides, we evaluated the influence of the duration of lateral decubitus on the spread of hyperbaric bupivacaine during spinal anesthesia. METHODS: Spinal anesthesia with 1.2 ml of hyperbaric 0.5% bupivacaine (6 mg) was administered with a 25-gauge Whitacre unidirectional needle to 50 ASA 1 patients undergoing unilateral knee arthroscopy. The patients were allocated randomly to three groups according to the duration of lateral decubitus after spinal injection in the lateral position operation side dependent: Group 1, 10 min in lateral decubitus then supine; Group 2, 20 min in lateral decubitus then supine; Group 3, 30 min in lateral decubitus then supine. Sensory and motor block (pinprick/modified Bromage scale) as well as skin temperature were compared between the dependent and nondependent sides. Circulatory variables were recorded for 10 min after being turned supine. RESULTS: The sensory block between dependent and nondependent sides were significantly different in Group 3. In Group 1, the level of maximum sensory block was higher than Group 3 on nondependent side. There was no difference in the number of patients having achieved Grade 3 and 0 motor block among three groups on dependent and nondependent sides. The skin temperature in lateral decubitus was significantly higher on the dependent side than nondependent side in three groups. In Groups 1 and 2, the skin temperatures of nondependent side were increased after turned supine, but that was maintained during supine position in Group 3. The circulatory variables were stable in all 50 patients. CONCLUSIONS: We conclude that when a small dose of 0.5% hyperbaric bupivacaine is injected into patients in the lateral position, complete unilateral spinal anesthesia is achieved when the patients arekeep in a lateral position for more than 30 min after spinal injection.

Hypoxia from Erroneous Connection of a Nitrogen Tank for an Oxygen Tank: A case report / 대한마취과학회지

We present a case of hypoxia which occurred during the onset of general anesthesia in a small hospital. It was found that one of the oxygen tank which formed the central pipeline gas supply had been erroneously replaced by a nitrogen tank. Lack of strict observance of Compressed Gas Supply Standards by the gas supplier and the hospital personnel allowed it. We also emphasize that the oxygen analyzer should be counted as an essential monitor in every anesthesia. Oxygen analyzer detects the supply of intraoperative hypoxic gas admixture promptly and effectively.

Hypoxia from Erroneous Connection of a Nitrogen Tank for an Oxygen Tank: A case report / 대한마취과학회지

We present a case of hypoxia which occurred during the onset of general anesthesia in a small hospital. It was found that one of the oxygen tank which formed the central pipeline gas supply had been erroneously replaced by a nitrogen tank. Lack of strict observance of Compressed Gas Supply Standards by the gas supplier and the hospital personnel allowed it. We also emphasize that the oxygen analyzer should be counted as an essential monitor in every anesthesia. Oxygen analyzer detects the supply of intraoperative hypoxic gas admixture promptly and effectively.

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.