The patients, scheduled for more than 6 hours of elective abdominal surgery, were randomized to two groups. Sixteen patients in Veen F (V) group received Mg²⁺ - free acetated Ringer's solution. Fourteen patients in Physio140 (P) group received acetated Ringer's solution containing 1mmol·l ^-1 Mg²⁺. In the V group, ionized magnesium concentrations were gradually decreased, but the reduction in ionized magnesium concentrations was significantly inhibited in the P group. In the P group, the ionized chloride concentration was significantly increased 6 hours after the start of the surgery. In the V group, the reduction ratio of ionized magnesium from start to end of anesthesia was well-correlated to the volume of fluid infusion, not to the volume of blood loss, transfusion, or urine. The acetated Ringer's solution containing 1mmol·l ^-1 Mg²⁺ is useful to inhibit the decrease in ionized magnesium concentrations during long (over 6 hours) elective abdominal surgery.

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  We often use both general and epidural anesthesia for pediatric surgery in abdominal or lower extremities for intraoperative and postoperative analgesia. But local anesthetic intoxication (LAI) tends to be overlooked under general anesthesia. We retrospectively reviewed LAI induced by epidural anesthesia for pediatric patients during the last decade. Neurological signs and symptoms of LAI induced by mepivacaine were observed in 17 cases (0.002%) in the operating room and the general wards. They were treated with oxygen inhalation, mask ventilation and administration of anticonvulsants. They recovered rapidly without neurological damage after treatment. It was suggested that the main cause was not the intravascular injection but the accumulation of mepivacaine due to its excessive or long-term administration. Anesthetists should administer an appropriate dose of local anesthetic in order to avoid LAI during epidural anesthesia for pediatric patients.

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  BIS sensors have been developed as three or four electrodes placed on the forehead. The manufacturer recommends that BIS sensors should be placed in predetermined positions in the frontal region. However, for certain neurosurgical operations, the operating field does not allow frontal placement of the BIS sensor. We have already compared BIS values obtained from frontal and occipital areas during surgery, and BIS showed a strong correlation between frontal and occipital montages. This time, we report 2 cases undergoing Awake Craniotomy with BIS sensors placed on their occipital areas. We were able to get stable recordings of BIS, and evaluate and change the depth of anesthesia during surgery. It may be a significant procedure in Awake Craniotomy to measure BIS with the sensor on the occipital area.

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  Carboplatin (CP) is commonly used for the treatment of ovarian carcinoma. Anaphylactic reaction to CP is rare, but it could be life-threatening. The risk of hypersensitivity reactions to CP increases during the course of frequent treatments for relapsed ovarian carcinoma. Although several investigators have reported hypersensitivity reactions to intravenously administered CP, few case reports have been presented regarding hypersensitivity reactions to intraperitonealy administered CP. We report here a case of an intraoperative anaphylactic reaction to intraperitonealy administered CP in a 57-year-old woman who had received ten courses of CP treatment.

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  Over the last two decades, transcranial doppler sonography (TCD) has been used for measuring cerebral blood flow velocity and also for diagnosing and evaluating cerebral ischemia in patients with vasospasms after subarachnoid hemorrhage and in many individuals with ischemic cerebrovascular disease. TCD has also been reported as a useful tool for preventing cerebral ischemia during reconstructive surgery of the cervical artery such as a carotid endarterectomy, or an aortic arch reconstruction under cardiopulmonary bypass. Although clinical examiners require specific knowledge and skills to perform TCD, intraoperative TCD is recognized as a beneficial method for predicting cerebral ischemia that has a relatively high degree of sensitivity and specificity. Because TCD monitoring is non-invasive and has real-time characteristics, continuous assessment can be performed in the majority of patients in whom the occurrence of cerebral ischemia is anticipated. This article describes the principle of TCD and the usefulness of the procedure in various clinical settings, and reviews the factors that need to be considered when monitoring blood flow and interpreting the results.

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  In critically ill, brain-damaged patients, it is difficult to directly evaluate cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRO₂) , because their circulatory instability sometimes Iimits radiological examinations, especially magnetic resonance spectroscopy. However, oxygen saturation of jugular vein (SjvO₂) is an index of the balance between CBF and CMRO₂. Because the fiberoptic jugular venous catheter makes continuous monitoring of SjvO₂ possible, this catheter is useful especially in exhibiting changes in cerebral oxygen demand/supply balance. Changes in fiberoptic SjvO₂ in response to therapeutic maneuvers provide valuable information about ongoing pathophysiology in the brain and the appropriateness of planned therapeutic goals. SjvO₂ is important from the standpoint of brain-oriented therapu but also from that of a systemic therapeutic approach, because SjvO₂ is affected by respiratory, circulatory and body fluid parameters: arterial carbon dioxide tension, arterial oxygen tension, mean arterial blood pressure, and hemoglobin concentration. Jugular venous blood is also a source of information on pH, carbon dioxide tention, blood lactate, blood glucose and temperature. Comparison of these parameters in jugular venous blood with those obtained from arterial blood gives further information concerning cerebral ischemia. SjvO₂, especially fiberoptic SjvO₂, along with the other parameters obtained by jugular venous sampling, is of value in critically ill brain-damaged patients, because signals from the brain are very limited in these patients.

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  Near-infrared spectroscopy (NIRS) is a non-invasive, real-time method for monitoring cerebral oxygenation. We used in three cases to detect brain ischemia intraoperatively. We successfully monitored cerebral oxygenation during a carotid endarterectomy and an endovascular repair of an aortic arch aneurysm. In the third case, NIRS revealed no abnormal patterns of cerebral oxygenation during an aortic arch replacement. Nevertheless, this case was complicated by the locked-in syndrome postoperatively. In conclusion, NIRS monitoring is useful for the detection of regional cerebral oxygenation, but it does not reflect cerebral oxygenation in all areas. This limitation should be noted when NIRS is applied to intraoperative monitoring of cerebral oxygenation.

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  We monitored blood flow insufficiency using motor-evoked potential (MEP) during intracranial aneurysm surgery. The study population consisted of 220 patients with intracranial aneurysms who underwent surgery with intraoperative MEP monitoring. Anesthesia was maintained by the continuous infusion of propofol. All patients received a bolus injection of vecuronium bromide followed by drip-infusion to maintain a stable level of neuromuscular blockade. There was no postoperative motor paresis in 193 patients whose MEP remained unchanged. Of the other 27 patients, 25 manifested transient MEP changes. Of these 25 patients, 14 did not present with postoperative motor paresis ; transient motor paresis was recognized in the other 11. In two patients, MEP disappeared and did not recover. These patients developed severe hemiparesis and a postoperative computerized tomography scan revealed a new low-density area in the internal capsule.

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  The purpose of this study was to examine the indication and problems of intraoperative spinal cord monitoring using spinal cord-evoked potentials (SCEP). We reviewed 616 cases of spinal surgery and 60 cases of intraoperative spinal cord monitoring. Intraoperative spinal cord injury occurred in the following surgeries, anterior decompression through the posterior approach for thoracic spinal cord compressive disorders, resection and/or coagulation of spinal arteriovenous malformation, resection of intramedullary spinal cord tumor, posterior occipitocervical fusion, anterior fusion of thoracolumbar spine, posterior decompression of thoracic spinal cord, and scoliosis surgery. These procedures might be an indication for spinal monitoring. Problems of spinal cord monitoring using SCEP are: 1) difficulty in prevention of posterior cord injury during resection of intramedullary spinal cord tumor, 2) impossible to predict gray matter injury, 3) imperfect detection of motor pathways disorder, 4) misidentification of neurological dysfunction.

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  The authors evaluated the relation between radiographic and analgesic spread during epidural block. An epidural catheter was inserted in 90 patients. The analgesic area was determined by pinprick after a 5-ml injection of 1.5% lidocaine, and epidurography was performed after a 5-ml injection of 240 mgI·ml ^-1 iotrolan. Patients were assigned to three groups according to catheter tip position (group C: C-T4; group T: T5-T10; group L: T11-L) , and patterns of spread were compared. The total radiographic spread correlated well with analgesic spread (right side: Y=0.81X+0.16, r=0.92, p<0.01; left side: Y=0.78X+0.46, r=0.91, p<0.01) . The mean distance between the predicted catheter tip and radiographically determined positions was 1.0 +/- 0.8 segments: the value in group T was significantly larger than that in groups C (p<0.05) and L (p<0.01) . Although the correlation of radiographic spread with age was statistically significant (r=0.39, p<0.01) , great individual variation in spreading pattern was seen in all groups. Epidurography is useful for indicating epidural catheter position and can help to predict the exact dermatomal distribution of analgesic block.

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  The author overviewed the reports that covered the relationship between epidural pressure and the spread of epidural anesthesia, and found no evidence that the patency of the intervertebral foraminae was directly related to the epidural pressure after epidural anesthetic injection. Epidural compliance and epidural resistance may have an important role in determining the epidural pressure after epidural anesthetic injection.

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  Many investigators have described the differences in dose requirement of local anesthetics for epidural anesthesia from patient to patient. We discussed the possible mechanisms for relationships between the epiduroscopic findings and the spread of epidural anesthesia. Epiduroscopy showed the alterations in its findings according to age, vertebral regions, pregnancy and histories of previous epidural anesthesia. The alteration of the epidural structure may affect the spread of local anesthetics in the epidural space.

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  Assessing the surgical level of epidural anesthesia is difficult. Several techniques have been proposed to assess the level even under general anesthesia. However, there are many factors that affect the level (i.e., time after injection, dosage and concentration of anesthetic, general anesthetic technique, and so forth) , and, thus, no perfect methods exist. Anesthesiologists should be aware of the possibility that sensory level or the depth of anesthesia is not sufficient especially when epidural anesthesia is combined with general anesthesia. It is recommended that larger concentrations of local anesthetic be used.

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