The effects of halothane, enflurane and isoflurane on hepatic function in 50 Sprague-Dawley rats in the presence of acute mild hypoxic(oxygen 14%) condition were compared. Anesthetics were administered in 1 MAC halothane (1%), enflurane(2.2%), isoflurane(1.4%) with 40% oxygen for 1 hour, 24 hours later serum alaninie aminotransferase(ALT) and asparate aminotransferase(AST) measured. There were no statistically significant differences of ALT among study groups. There were significant differences of AST between hypoxic group and halothane, enflurane and isoflurane groups.

This study shows that admintistration of 40% oxygen with 1 MAC halothane, enflurane and isoflurane in acute mild hypoxic condition was not harmful on hepatic function.

Brain ischemia due to a critical reduction in cerebral blood flow is a common cause of irreversible brain damage. Ischemia is invariably accompanied by an increase in tissue lactate concentration due to anaerobic metabolism of glucose and energy failure.

Despite new insights into the pathophysiologic mechanism of cerebral ischemia, the clinical therapeutics of cerebral ischemia is usually limited to agressive anticoagulation and supportive measures.

But. recently, new pharmacological agents including calcium channel blocking agent, perfluorocarbon, free radical scavenger and opiate antagonist are considered as possible therapeutic application for restoration of blood flow to areas of focal ischemia in both laboratory and clinical trials.

Naloxone, an opiate antagonist, has been reported to improve neurological function, spinal blood flow and somatosensory evoked potentials after spinal injury. Thus, Endogenous opioids might play a role in pathophysiology of central nervous system ischemia and that opiate antagonist might be of benefit in the treatment of experimental stroke.

But, on the other hand. there are many evidences that naloxone is not benefical. So use of naloxone for the treatnebt of ischemia insult is controverial.

Therefore, The present investigation was undertaken to elucidate the effects naloxone on cerebral ischemia by measurement of the cerebral energy metabolites concentration.

Cerebral ischemia was produced in spontaneously hypertensive rat(SHR) by bilateral common carotid artery ligation. Naloxone(1mg/kg) was administered intraperitoneally 30 min after the carotid artery ligation.

The results obtained were as follows :

1) There were no differences in the concentration of APT and lactete between normotensive Sprague-Dawley rats and SHR.

2) In bilateral common carotid artery ligated SHR, the concentration of APT was considerable decreased and that lactate was slightly increased.

3) Naloxon didn'y change the cerebral energy metabolism in ischemic model. These data indicated that naloxone had no benefical effect on cerebral ischemia but for definite conclusion, more controlled experiments must be performed.

A major problem with general anesthesia for Cesarean section is the incidence of maternal awareness and unpleasant recall occasioned by the use small doses and low concentrations of anesthetics to minimize neonatal effect.

To reduce awareness, various measures have been attempted. The purpose of study is to assess the influence of ketamine, halothane and enflurane on the maternal awareness and neonatal depression under N₂O for Cesarean section. This study group consisted of 48 patients undergoing Cesarean section under general anesthesia.

Anesthesia was induced by thiopental, succinylcholine chloride injected, and maintained until baby delivery with according to divided group.

Group 1: thiopental, 50% N₂0

Group 2: thiopental, 50% N₂O and ketamine(0.25mg/kg)

Group 3: thiopental, 50% N₂O and 0.5% halothane

Group 4: thiopental, 50% N₂0 and 0.6% enflurane

The results were as follows :

1. The incidence of awareness of 50% N₂O group was 66.7%.

2. The incidence of awareness of ketamine, halothane and enflurane group was 8.3%.

3. When induction-delivery time is 8 minutes or less, there was no correlation between induction-delivery time and awareness.

4. There was no neonatal depression.

The use of ketamine, halothane and enflurane appears to be effective in preventing awareness when induction-delivery time is 8 minutes or less.

Diazepam(Valium), a benzodiazepine derivative, has been widely used for the treatment of anxiety and seizures. Recently, diazepam has been used as preanesthetic medication, preparation for endoscopy, bronchoscopy, cardiac catheterization, arteriography, and to supplement local anesthetic during surgery. One patient who suffered cardiopulmonary arrest after receiving small doses of diazepam intravenously is reported in view of the frequent intravenous use of diazepam. Small doses of intravenous diazepam can cause respiratory arrest. We suggest that equipment and personnel trained in cardiopulmonary resuscitation and physostigmine be available a whenever diazepam is administered intravenously.

Vasovagal syncope is one of the most common causes of transient syncope during anesthesia for elective surgery in patients with a history of syncope and requires special attention and management of anesthetics. The causes and pathophysiological mechanism of this condition are poorly understood, but it has a benign clinical course and recovers spontaneously. However, in some cases, this condition may cause cardiovascular collapse resulting in major ischemic organ injury and be life threatening. Herein we report a case and review literature, regarding completing anesthesia safely during an elective surgery of a 59-year-old female patient with history of loss of consciousness due to suspected vasovagal syncope followed by cardiovascular collapse and cardiac arrest, which required cardiopulmonary resuscitation and insertion of a temporary pacemaker and intra-aortic balloon pump immediately after a fine-needle aspiration biopsy of a lung nodule located in the right middle lobe.