[Epidural anesthesia for femoral head replacement in a spinocerebellar ataxia patient: a case report].

Perioperative management of a spinocerebellar ataxia patient by epidural anesthesia is reported. A 67-year-old woman with left femur neck fracture underwent femoral head replacement. An epidural catheter was placed without difficulty at the L3-4 interspace using the loss of resistance technique. A total of 1% mepivacaine 13 ml was administered in divided doses to obtain bilateral T5 analgesic level. Hypotension (79 mmHg systolic) was observed transiently, and ephedrine 8 mg was administered which successfully elevated blood pressure. Overall, hemodynamics and respiratory status were stable. Postoperative analgesia was maintained by infusion of 0.2% ropivacaine at 2 ml x hr(-1). The patient's postoperative course was uneventful, and her neurologic conditions remained unchanged.

[Continuous infusion of low-dose remifentanil for palliation of pain with epidural catheterization].

BACKGROUND: To prospectively determine the safety and effectiveness of continuous infusion of low-dose remifentanil for the reduction of pain in patients for epidural catheterization. METHODS: This study was approved by the institutional review board. Written informed consent was obtained. Fifty two patients (27 men, 25 women, age range 16-96 years, mean age 68 years) were given continuous infusion of various rates of application (none, 0.02, 0.05, and 0.07 microg x kg -1 x hr-1) of remifentanil. Blood pressure, heart rate, pulse oximetry oxygen saturation and respiratory rate were recorded during the procedure of epidural catheterization. Pain score was measured with the visual analogue scale (VAS), and complications including muscle stiffness, nausea and vomiting, and depressed level of consciousness were monitored. RESULTS: Every rate of application, pulse oximetry oxygen saturation and systemic blood pressure were decreased but the reduction was not marked. The muscle stiffness, nausea and vomiting, and depressed level of consciousness were not observed in all the cases. No other serious complications were observed. CONCLUSIONS: Continuous infusion of low-dose remifentanil is a safe and effective method for palliation of pain in epidural catheterization.

Effects of systemic deep hypothermia and subarachnoid block on the longitudinally conducting evoked spinal cord potentials in man.

The present study reports the effects of systemic deep hypothermia (SDH) and subarachnoid block (SAB) on the longitudinally conducting evoked spinal cord potential (conducting ESCP) in man. Before induction of anesthesia, a pair of bipolar catheter electrodes was introduced to the epidural space: one at the level of the cervical enlargement and the other at the lumbosacral enlargement. The conducting ESCP was produced by electrical stimulation through the upper electrode and recorded through the lower electrode, and vice versa. SDH Study: Subjects were 6 patients who underwent replacement surgery of an aortic aneurysm with deep hypothermia anesthesia. The peak latency of the ESCP was gradually prolonged and the duration was widened with cooling via extracorporeal circulation. The amplitude of ESCP showed a biphasic change over the course of cooling with a turning point of around 30 degrees C in esophageal temperature. The ESCP was well observed until blood temperatures as low as near 10 degrees C. The result shows that ESCP is available as an intra-operative monitoring parameter of the spinal function even under SDH. SAB Study: Subjects were 7 patients, 6 of whom had SAB and the remaining 1 intravenous application of a local anesthetic. The conducting ESCP was markedly depressed or disappeared completely even after SAB with clinical doses of various local anesthetics, while it was hardly affected by the intravenous application. The result implies that SAB causes, at least partially, the conduction block within the spinal cord.

Induction of neuronal tolerance by electroconvulsive shock in rats subjected to forebrain ischemia.

We have examined ischemic tolerance induced by electroconvulsive shock before exposure to forebrain ischemia. Subjects were 40 rats, which were randomly allocated to control, single ECS (sECS), repeated ECS (rECS) or sham group. sECS group and rECS group received ECS only once 2 days before the subsequent 8-min forebrain ischemia and once a day for 9 consecutive days until 2 days before the exposure to ischemia, respectively. Forebrain ischemia was produced by modified bilateral carotid artery occlusion technique. Control group underwent brain ischemia without ECS pretreatment. Sham group received ECS without following exposure to ischemia. Pyramidal cell injury of the hippocampal CA1 sector was microscopically examined on the 7th day after the ischemic exposure or the sham operation. Damage of the pyramidal cells was assessed by the injury ratio, which was ratio of non-viable pyramidal cells to the whole pyramidal cells. The injury ratios of CA1 pyramidal cells in sECS, rECS and control groups were 30.5 +/- 10.8 (n=10), 42.3 +/- 18.4% (n=10) and 90.4 +/- 2.9% (n=9), respectively. The injury ratios in sECS and rECS groups were lower than the ratio in control group (p<0.01), while the ratios of sECS and rECS groups were not different. The pyramidal cells in sham group were intact. Our results indicate that both preconditionings of sECS and rECS have a potency to induce delayed tolerance against temporary forebrain ischemia, though the potency was not different between sECS and rECS. Electroconvulsive shock may be added to the list of preconditioning stimuli to protect brain against ischemic neuronal damage.

[Two cases of gravity dependent atelectasis after laparoscopic nephrectomy].

Two patients developed postoperative pulmonary atelectasis after receving laparoscopic nephrectomy in the lateral kidney position. In both patients, the trachea was intubated with a single lumen tube and the lateral kidney position was kept over 9 hours. Because the pulmonary atelectasis had developed on the lower side of the lungs, we considered it as the gravity dependent atelectasis (GDA). We have also described treatments and prophylaxis for GDA in this case report.