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We surveyed anesthetic practices and the use of cerebral monitoring and brain protective therapies during cerebral aneurysm surgery by sending a questionnaire to 822 hospitals in Japan. Three hundred and fifty four hospitals responded. For induction, 51% used thiopental, 41% used propofol, and 94% supplemented induction with fentanyl. For maintenance 45% used isoflurane, 29% used sevoflurane, and 26% used propofol. Only 6% used EEG and/or evoked potentials in most of their patients. Specific brain protective measures were used in most of the hospitals. If used, 97% used mannitol, 43% used steroids and 23% used a certain level of induced hypothermia. When mild hypothermia was used, 39% used 33-34 degrees C, 59% used>34 degrees C, 2% used <33 degrees C, and only 4% used mild hypothermia in every patient. During temporary clipping, 18% kept the blood pressure equal to the level when awake, while 56% used induced hypotension. To control blood pressure during extubation, 72% used nicardipine or nitroglycerine. The use of intraoperative brain protective therapies were common but brain monitoring was not the standard.

We have used spinal cord stimulation (SCS), diazepam and nitrous oxide for maintenance of general anesthesia. Blood pressure was maintained by bolus administration of nicardipine for the removal of pheochromocytoma. Both SCS and nicardipine reduced systemic vascular resistance and SCS increased cardiac output. However, neither SCS nor nicardipine could inhibit the release of norepinephrine. SCS proved to be useful as one of anesthetic technique during the removal of pheochromocytoma, and also in the management of postoperative pain and the prevention of complications.

A 480 g, 38-day-old female infant underwent ventriculo-peritoneal shunt surgery for hydrocephalus after intra-ventricular hemorrhage. The patient was born at a gestational age of 25 weeks and 5 days, weighing 600 g, as one of twins by a cesarean section. Although respiratory distress syndrome developed, it was relieved with surfactant. The esophagus was easily perforated by a gastric tube. At the age of 7 days, PDA was closed conservatively with indomethacin. Anesthesia was induced and maintained with fentanyl (induction dose 4 micrograms.kg-1, total dose 6 micrograms.kg-1) and vecuronium. Ventilation was controlled with oxygen and air (FIO2 0.21-0.25). The main problems encountered by anesthetists in the perioperative period were; fluid management (hyperkalemia, hyponatremia, infusion volume), bradycardia due to increased intracranial pressure, body temperature control (hypothermia), and transport to the operating room. In anesthesia for extremely low birth weight (extremely premature) infants, utmost care and proficient procedure are required because of their immaturity, fragility and smallness.

The first patient with hypoplastic left heart syndrome who was treated successfully by palliative surgery at our hospital is reported. Soon after birth, the female infant showed tachypnea and cyanosis, and was transferred to our institution under a presumptive diagnosis of HLHS. Although cardiologists confirmed the diagnosis by two-dimensional echocardiography, the surgery was postponed for one month because it was possible to keep the ductus arteriosus open without PGE1, and the patient showed no deterioration. Fortunately, an abnormal vessel connecting the left atrium with the superior vena cava relieved severe pulmonary venous congestion by diverting the blood flow. During the pre-CPB period, frequent adjustment of the oxygen concentration and ventilator setting was required in order to keep the blood gas values optimal compared with the values before surgery. After CPB, adequate blood pressure using catecholamines and hyperventilation with 100% oxygen was necessary to increase the pulmonary blood flow and to decrease the pulmonary vascular resistance. It is concluded that preservation of the balance between PVR and SVR during the perioperative period, and adequate systemic arterial pressure after CPB are crucial. Furthermore, constant and intense observation is mandatory to facilitate immediate treatment even after surgery in case of systemic hypoperfusion due to excessive pulmonary blood flow.