The initial distribution volume of glucose and cardiac output after haemorrhage in dogs

The purpose of the study was to evaluate the role of insulin in glucose kinetics after glucose administration using an insulinogenic index to indicate the magnitude of insulin response. The initial distribution volume of glucose (IDV-G) was calculated with a one-compartment model from repeated measurements of plasma glucose concentration three to seven minutes after administration of 100 mg.kg-1 glucose. The IDV-G was compared with the insulin response and the thermodilution assessments of cardiac output, measured simultaneously both before and after induced haemorrhage (30 ml.kg-1 over 30 min) in 12 adult mongrel dogs. The plasma insulin concentration was measured during the procedure and insulinogenic indices were calculated. There was no correlation between the IDV-G and insulinogenic indices, but there was a correlation between the IDV-G and thermodilution cardiac output before and after induced haemorrhage (r = 0.85, n = 24, P < 0.001). We conclude that the initial distribution volume of glucose is an indication of cardiac output in normo- and hypovolaemic dogs. Modification of glucose kinetics by the insulin response to glycaemic stimuli was negligible in that short period of time.

[A marked elevation in serum CPK following sevoflurane anesthesia]

A one year-old girl with an arachnoid cyst received an arachnoid cystperitoneal shunt operation two tims, firstly under sevoflurane anesthesia, and secondarily under isoflurane anesthesia. After sevoflurane anesthesia, her serum CPK level increased markedly up to 7550 mU.ml-1, but such an increase was not observed following isoflurane anesthesia. The perioperative management was almost identical on these two occasions. A combination of sevoflurane anesthesia and succinylcholine might cause a significant increase in the serum CPK level.

[An application of a study of medical history to clinical medicine - for better understanding of medical history and its application to clinical medicine]

A study of medical history aims to correctly understand the progress in basic and clinical medical science and to effectively offer better medical service to our patients. The study of medical history has several important advantages, such as; 1) to understand the present medical science in depth and to shorten the duration of time needed to understand the present medicine, 2) to understand the disadvantages of the present medical sciences realizing that they are not perfect, 3) to correctly understand literature and historical documents on medical science, 4) to make and maintain accurate medical records and documents, 5) to create new concepts and 6) to prevent us from developing a rigid way of thinking. Two cases of the application of medical history to clinical medicine are shown. The first is in regard to perioperative blood transfusion. As it was suggested to me by a report that preoperative blood transfusion caused suppression of immune response in kidney transplantation, I thought a routine use of blood transfusion for surgical patients with malignant tumors would lead to a high postoperative recurrence rate of malignancy. Therefore, such a routine use of blood has been avoided inn our institution for these twenty years. The second case is in regard to excitement during the induction of inhaled anesthetics. At present the excitement is considered to be caused by inhibition of the cerebral cortical function. However, our recent clinical study based on Dr. Maeda's report published in 1935 has revealed that the excitement observed during the induction of inhaled anesthesia is caused mainly by stimulation of the trigeminal nerves. The importance of medical history should be much more stressed for medical training of students and residents as well as physicians. It should be widely and deeply applied to the clinical practice of medicine, though it is not so easy to do this. Otherwise, the study of medical history may be considered as only a hobby for retired physicians.

[Clinical study on total intravenous anesthesia with droperidol, fentanyl and ketamine--20. Summary of three thousand cases and the future of this anesthetic method]

Total intravenous anesthesia with droperidol, fentanyl and ketamine (DFK) was given to over three thousand patients during four years from April 1989 through March 1993. The patients ranged in age from three months to eighty seven years. They underwent surgical, orthopedic, gynecological, thoracic, plastic and otolaryngeal surgeries, but patients who underwent craniotomy and obstetric operations were excluded. None of them developed any serious complications primarily due to DFK. DFK has many advantages such as the broad safety margin for three agents employed in DFK, no accident by N2O, no air pollution, empty bowels, no increase in middle ear pressure etc, while this has disadvantages such as high blood pressure, slow awakening from anesthesia and unpleasant dreams. Calcium channel blockers are very effective for antagonizing high blood pressure, and rapid recovery from anesthesia can be easily obtained by reducing ketamine dose given and also by application of epidural block. Intraoperative dreams may be avoided by concomitant use of benzodiazepines. Thus we are convinced that DFK can be a good as well as convenient anesthetic method for clinical anesthesia.

[Clinical study on intraoperative hyperketonemia in non-diabetic surgical patients under general anesthesia]

We measured plasma 3-hydroxybutyrate (3-OHBA) concentrations in 925 non-diabetic surgical patients who underwent various surgical procedures under various types of general anesthesia. Lactated Ringer's solution only was used as an intraoperative fluid. Among them, 46 patients (4.9%) developed high 3-OHBA levels of over 500 microM.l-1 during surgery. The causes of observed hyperketonemia would be surgical stress and preoperative fasting irrespective of 8 types of general anesthesia. Blood glucose, lactic acid, base excess and pH were not influenced by hyperketonemia. Prolonged recovery from anesthesia was not observed in any patients with hyperketonemia. Without any specific treatments, plasma 3-OHBA levels were unchanged or rather decreased in 70% of the patients whose 3-OHBA levels were over 500 microM. The results suggest that hyperketonemia below 500 microM.l-1 is not always disadvantageous in nondiabetic patients under general anesthesia.

[Effects of sevoflurane anesthesia on serotonin metabolism in rat brain]

To elucidate the mechanism of general anesthesia, effects of sevoflurane anesthesia on serotonin metabolism in rat brain were studied. Three percent sevoflurane was administered for twenty minutes to Wistar male rats weighing 230-270g under spontaneous respiration. The rats were sacrificed by decapitation and the brains were rapidly removed. They were dissected into nine discrete regions, locus coeruleus, pons plus medulla oblongata, hypothalamus, thalamus, basal ganglia, midbrain, hippocampus, amygdala and cerebral cortex. The contents of serotonin (5-HT) and one of its major metabolites, 5-hydroxyindole-3-acetic acid (5-HIAA) were measured by high performance liquid chromatography with the dual-cell coulometric detector before anesthesia, 20 minutes after the start of anesthesia and at the recovery from anesthesia. Significant increases in 5-HT levels were observed in the pons, hypothalamus, midbrain, amygdala and cerebral cortex by sevoflurane anesthesia as compared with the control group. 5-HIAA levels decreased significantly in the thalamus by sevoflurane anesthesia, while an appreciable increase in 5-HIAA levels was observed in the basal ganglia at the recovery from anesthesia. It is concluded that 5-HT metabolism is significantly suppressed in the pons, hypothalamus, thalamus, midbrain, amygdala and cerebral cortex during sevoflurane anesthesia and this change in 5-HT metabolism may be associated with a mechanism of sevoflurane anesthesia.

[Medical aspect of the winter march of the Fifth Regiment of the Eighth Military Division in the winter of 1902 - particularly concerning the cause of Major Yamaguchi's death]

Two hundred and ten military soldiers of the Fifth Regiment of the Eighth Division of the Japan Imperial Army joined a marching practice in the end of January, 1902, but 193 soldiers out of 210 died due to severe frost-bite during stormy weather and only seventeen, including Major Yamaguchi, were rescued to survive and brought to the Veteran's Administration Hospital at Aomori. This accident was most tragic and world-shaking for the Japanese people as well as for the Japanese Imperial Army. In December of 1991, an admission record of the Veteran's Administration Hospital at Aomori was found in the residence of Dr. Murakami of Aomori City. Judging from its handwriting, this record was written by a military physician Ki-ichi Murakami, Dr. Murakami's uncle. The record describes the details of seventeen patients, most of whom were severely injured and frost-bitten during the winter march. The content of this newly discovered record is similar to the report written by the military physicians of the Fifth Regiment which appeared in the Japan Imperial Military Medical Journal, but a more detailed description about Major Yamaguchi's vital signs, and symptoms of his frost-bite were found in the former. In the journal, Major Yamaguchi was reported to have died because of sudden cardiac arrest but Jiro Nitta described in his novel "Death March on Mount Hakkoda" that he committed suicide using his gun. However, this record strongly tells us that both of his hands, as well as both lower extremities, were severely frost-bitten and swollen and that he could not pull the trigger of his gun with his fingers. Since Jiro Nitta's novel has been published, it is widely accepted that Major Yamaguchi committed suicide with his gun. But we do not have any definite proof to substantiate his suicide. The present detailed survey on the medical references strongly suggests that he could not have pulled his gun's trigger by himself.

[EEG pattern during total intravenous anesthesia with droperidol, fentanyl and ketamine]

We evaluated EEG pattern during total intravenous anesthesia with droperidol, fentanyl and ketamine (DFK). Four surgical patients, ranged in age from 35 to 43, were the subjects of this study. Two male underwent oral or orthopedic surgery and the other two female patients underwent gynecological surgery. They were all free from hepato-renal dysfunction and central nervous system disorders. For the induction of anesthesia, droperidol 0.06-0.1 ml.kg-1, fentanyl 2-4 micrograms.kg-1, and ketamine 1.0-1.5 mg.kg-1 were slowly administered intravenously. A total dose of 5-15 micrograms.kg-1 of fentanyl was given intravenously with continuous infusion of ketamine 2 mg.kg-1.h-1 during the surgical procedure. The total amounts of fentanyl and ketamine administered were 4.9-22.2 micrograms.kg-1 and 240-340 mg.kg-1, respectively. We used HZI'Brain Function Monitoring system to evaluate their EEG patterns. When adequate depth of anesthesia was obtained as clinically evaluated by vital signs, theta wave pattern was dominant on the EEG tracings in any of these patients. DFK anesthesia would provide a stable anesthetic course, if those drugs are administered adequately considering vital signs including systemic blood pressure, heart rate, lacrimation and involuntary muscle movements of the face and extremities.

[Perioperative management of patients on long-term administration of psychotropic drugs]

We experienced perioperative management of thirty two surgical patients complicated with either schizophrenia or depression on long-term administration of psychotropic drugs during a period of three years from 1989 through 1991. They underwent various operative procedures under either general anesthesia or epidural anesthesia. Mental confusion was most frequently encountered in immediate postoperative period. The longer the patients had been treated with psychotropic drugs, the more postoperative complications were observed. We lost four patients within two weeks postoperatively. They all underwent laparotomy and had been treated with psychotropic drugs for a prolonged period. No significant association between the types of anesthesia and postoperative complications was observed. Surgical patients on long-term administration of psychotropic drugs should be managed carefully particularly during postoperative period.

[Intensive care of a postpartum patient complicated with HELLP syndrome]

We reported our intensive care experience of a postpartum patient with HELLP syndrome. We administered haptoglobin immediately after the delivery in order to prevent renal insufficiency following hemoglobinuria. Continuous veno-venous hemofiltration was undertaken and plasma exchange was also employed to overcome hepatorenal insufficiency. After these procedures an improvement was observed in her hepatic and renal functions. Administration of haptoglobin and blood purification would be beneficial for patients complicated with HELLP syndrome.

[Anesthetic experience of emergency cesarean section for a patient with myotonic dystrophy]

We report an anesthetic experience of a 28-year-old female patient complicated with myotonic dystrophy who underwent emergency Cesarean section due to threatened abortion. Anesthesia was induced with intravenous thiopental followed by topical spray of 4% lidocaine 5 ml to intubate trachea and maintained with neuroleptanesthesia with droperidol, fentanyl and nitrous oxide in oxygen. No muscle relaxant was used. The course of anesthesia and emergence from anesthesia were uneventful. However, the female infant, with Apgar score of 1 point at five minutes after delivery, died due to multiple organ failure three weeks after the delivery. Anesthetic management of a patient with myotonic dystrophy was also discussed with a literature review.

[Effects of ketamine on pituitary-adrenal axis in rats]

We examined the effects of ketamine (20 mg.kg-1) on plasma ACTH, Comp. B, aldosterone and ir-ANP levels in unstrained rats. We divided rats into two groups, saline group as control (saline group) and ketamine group (ketamine treated rats). Plasma samples were taken before ketamine or saline infusion to determine a pre-treatment value, and samples were also taken at 15, 30, 60 minutes after the infusion. ACTH, aldosterone and ir-ANP were measured by radioimmunoassay. Comp. B was determined by a fluorometric method. We obtained the following results: 1) Plasma ACTH levels increased significantly in the ketamine group, while there was no such a marked increase in the saline group. The slight increase in ACTH in the saline group could have resulted from handling during i.v. infusion or psychic stress; 2) Plasma corticosterone and aldosterone levels increased markedly in both groups. However, the magnitude of the adrenocortical response was significantly greater than in the saline group; 3) Plasma ir-ANP showed no significant change in both groups. These results suggest that ketamine stimulated pituitary-adrenal axis, and the adrenal stimulation produced by ketamine are greater than those induced by the stress of handling or psychic stress.

[Anxiolytic effect of preoperative showing of "anesthesia video" for surgical patients]

Over 60% of preoperative surgical patients are reported to suffer from preoperative anxiety. Since 1986, an anesthesia video, explaining our routine anesthesia procedures has been shown to elective surgical patients preoperatively at our clinic. In 1990, as our anesthesia method was modified, we revised this video and evaluated the effect of this video on their preoperative anxiety. Female patients, in general, have much more anxiety than male patients, and the female patients of 30-59 years of age were the most anxious about their surgical operations not about anesthesia per se. The patients who were to undergo a major surgery, such as gynecological patients also belonged to the most anxious patient group. After demonstrating the video any patient group including gynecological patients of 30-59 years of age was less anxious about the upcoming anesthesia and surgery.

[Clinical study on total intravenous anesthesia with droperidol, fentanyl, and ketamine--18. Effect on peripheral circulation as judged by core-peripheral temperature gradient]

Effect of total intravenous anesthesia with droperidol, fentanyl and ketamine (DFK) on peripheral circulation was studied by examining core-peripheral temperature gradient in twenty five patients who underwent abdominal surgery. A core temperature probe was attached on the forehead and peripheral probe on the palm of the hand of the side on which the blood pressure cuff was not applied. The temperature gradient was less than three degrees centigrade in 60% of the patients and the gradient was significantly less as compared with that of isoflurane anesthesia even at 300 minutes after the start of surgical operation. This advantage would have been caused by such factors as circulatory stimulating effect of ketamine, sympathetic blocking effect by droperidol and adequate postoperative analgesia by fentanyl and norketamine, a metabolite of ketamine. The results suggest that DFK would exert a beneficial effect on peripheral circulation, particularly during prolonged surgical procedures.

[Excessive nitrous oxide exhalation by postoperative patients in the recovery room]

Expired nitrous oxide from patients in the recovery room is considered to be the major source of air pollution. We measured expired concentrations of nitrous oxide in three patients and three volunteers. After only 5 minute inhalation of 50% nitrous oxide, it took over 2 hours for exhaled N2O concentration to decrease to 25 ppm in volunteers and after 30 minute inhalation, it took over 4 hours. The patients inhaled 50% nitrous oxide for 60, 165, 150 minutes, respectively and all patients expired nitrous oxide, the concentrations of which exceed 100 ppm over 3 hours. As to the patient who inhaled nitrous oxide for 150 minutes, expired nitrous oxide over 25 ppm was detected 10 hours after the end of anesthesia, and it was 4 ppm even after 20 hours. Any personnel including anesthesiologists and nurses working in the operating room can be exposed to high concentrations of nitrous oxide exceeding the permissible limit of 25 ppm, whenever they take care closely of their patients. We do not have any effective measures to protect us from this kind of air pollution except employing total intravenous anesthesia.

[A case report of total intravenous anesthesia for renal transplantation]

A 20-year-old female patient with chronic renal failure received renal transplantation under total intravenous anesthesia with droperidol, fentanyl and ketamine. Anesthesia was induced with droperidol 12.5 mg, fentanyl 100 micrograms, ketamine 100 mg and vecuronium bromide 5 mg, and maintained with fentanyl and ketamine. Ketamine was given continuously at a rate of 2.0 mg.kg-1.h-1. After the renal artery and vein of the donor kidney were anastomosed with the patient's internal iliac artery and vein, the urine output of 7.7 ml.min-1 was obtained. The patient recovered from anesthesia smoothly and her postoperative course was uneventful. Although plasma epinephrine, cortisol and ADH levels showed significant changes during anesthesia mainly due to surgical stress, they returned to normal values after the end of operation. We conclude that this method of anesthesia would be a choice for renal transplantation.

[An emergency operation for a Jehovah's Witness with ruptured thoracic saccular aneurysm]

A 49-year-old male "Jehovah's Witness" was transferred to our hospital with hypotension, abdominal pain, and abdominal distension, and a diagnosis of ruptured thoracic saccular aneurysm was made. He and his family insisted on having an emergency operation for his ruptured aneurysm without blood transfusion. After an intensive discussion among the patient, his family, surgeons, and the director of the hospital, we performed the operation without blood transfusion. The operation using cardiopulmonary bypass took about five hours under enflurane anesthesia, but he died of circulatory collapse fifteen hours after the end of operation. As there may be various opinions concerning how we should take care of Jehovah's Witness patients, we have to manage them case by case.

[Plasma levels of isosorbide dinitrate and its metabolites during intravenous infusion in surgical patients--effect of preoperative administration of isosorbide dinitrate]

Nineteen patients with ischemic heart disease were studied to determine plasma levels of isosorbide dinitrate (ISDN) and its metabolites, isosorbide-2-mononitrate (2-ISMN) and isosorbide-5-mononitrate (5-ISMN) for 6 hrs during intravenous administration of ISDN, using gas chromatography. Differences in plasma levels of these substances were also evaluated in patients with or without preanesthetic medication of ISDN. These patients ranging in ages from 42 to 80 years were administered ISDN intravenously at a rate of 1 micrograms.kg-1 x min-1 during anesthesia and surgery. Preanesthetic administration of ISDN consisted of transdermal application of 40 mg dose. Surgery included gastrectomy, pneumonectomy, extended cholecystectomy, radical mastectomy and so on under either enflurane anesthesia or neuroleptanesthesia. Plasma ISDN levels increased and reached a plateau 3 hrs after the start of intravenous infusion of ISDN in patients of both groups. Plasma 2-ISMN levels increased gradually and reached a plateau 5 hrs after the commencement of intravenous administration of ISDN in patients of both groups. Plasma 5-ISMN levels increased gradually reaching the peak 6 hrs after the start of intravenous infusion of ISDN in both groups. Plasma ISDN, 2-ISMN and 5-ISMN levels were slightly higher in patients who received preanesthetic ISDN than in those who did not receive preanesthetic ISDN. However, there were no statistical differences in plasma ISDN or 2-ISMN levels between the groups except prior to the infusion. On the contrary, plasma 5-ISMN levels were significantly higher in patients who received preanesthetic ISDN than in those who did not receive preanesthetic ISDN for 3 hrs after the start of the infusion.

[Clinical study of total intravenous anesthesia with droperidol, fentanyl and ketamine--effects of nicardipine, diltiazem and nifedipine on intraoperative hypertension]

Effects of Ca ion channel blockers, nicardipine, diltiazem and nifedipine on intraoperative hypertension were evaluated clinically in ninety surgical patients who received various surgical procedures under total intravenous anesthesia with droperidol, fentanyl and ketamine. When the systemic blood pressure exceeded 160 mmHg systolic at least for ten minutes, even though they received a total dose of 10-15 micrograms.kg-1 of fentanyl, one of the following three antihypertension drugs was administered:nicardipine 0.5-1.0 micrograms i.v., diltiazem 5-10 mg i.v. and nifedipine 5-10 mg intranasally. The effects were evaluated by measuring the systemic blood pressure, heart rate and rate pressure product, before the administration as well as 5, 15, 20 and 30 minutes after the administration. Following the injection of the drug a significant 10-20% reduction in the mean systemic blood pressure was observed in the nifedipine group, while less decrease was observed in the diltiazem and nicardipine groups. The mean heart rate in the nifedipine group increased slightly, while a slight decreases was observed in the other two groups. Therefore the rate pressure product was reduced significantly in three groups, but there was no significant difference among them. No adverse episodes such as ischemic changes on E.K.G. and deterioration of the cardiovascular system were encountered in any patients. We conclude that any of these drugs, particularly nifedipine would be appropriate to control hypertension during total intravenous anesthesia with droperidol, fentanyl and ketamine.

The initial distribution volume of glucose and cardiac output in the critically ill

Blood or plasma glucose concentration can be measured accurately and rapidly. However, after a glucose challenge metabolism may modify glucose kinetics, so that glucose has not been used as an indicator for dilution volumetry. To test the hypothesis that the initial distribution volume of glucose (IDVG) reflects cardiac output rather than glucose metabolism in the critically ill, the relationship between IDVG and thermodilution cardiac output was evaluated at 27 points in 13 non-surgical, critically ill patients without congestive heart failure. The IDVG was calculated from incremental plasma glucose concentrations using a one compartment model. Correlations were obtained between the IDVG and cardiac output (r = 0.89, n = 27, P < 0.001), and between the incremental plasma glucose concentrations three minutes after the injection and the IDVG (r = 0.94, n = 27, P < 0.001). No difference was found between the IDVG with or without continuous insulin infusions. The results indicate that the IDVG reflects cardiac output rather than glucose metabolism in patients without congestive heart failure.

[Hemodynamic and endocrine responses to prostaglandin E1 induced hypotension during enflurane anesthesia in surgical patients--evaluation by transesophageal echocardiography]

This study was undertaken to find a relationship between cardiac function indices and endocrine functions during prostaglandin E1 induced hypotension in surgical patients. Thirteen patients who underwent either orthopedic or gynecologic surgery were the subjects of the study. Systolic blood pressure decreased to 80 torr with prostaglandin E1 infusion (0.5-2 micrograms.kg-1 x min-1) under enflurane-N2O anesthesia. The cardiac function were judged by transesophageal echo-cardiography. Plasma ANP and ADH levels were measured by radioimmunoassay. Significant reductions in the left atrial diameter and A/R and significant increases in cardiac output were observed, but there were no significant changes in fractional shortening and pulmonary vein flow. Plasma ANP concentrations decreased significantly from 45.3 +/- 5.1 pg.ml-1 (mean +/- SE) of pre-hypotension to 32.6 +/- 2.2 pg.ml-1 of control, but plasma ADH levels increased significantly during hypotension (P < 0.05). We could not find any significant correlation between the cardiac function indices and plasma hormone levels. Transesophageal echocardiography is an excellent monitor during induced hypotension. It is difficult to predict the ANP and ADH levels by measuring cardiac function as judged by TEE.

[Effects of intravenous infusion of isosorbide dinitrate on hemodynamics during anesthesia and surgery]

Ninety nine patients with ischemic changes of the heart on preoperative and intraoperative ECG tracings were studied to evaluate effects of intravenous infusion of isosorbide dinitrate on hemodynamics during anesthesia and surgery. These patients ranging in ages from 24 to 80 years were administered intravenous isosorbide dinitrate at a rate of either 0.5 or 1 microgram.kg-1 x min-1 during anesthesia and surgery. Arterial blood pressure was not influenced with intravenous isosorbide dinitrate at the speed of 0.5 microgram.kg-1 x min-1 during anesthesia and surgery. The arterial pressure of the patients decreased slightly but significantly 30 min after the start of 1 microgram.kg-1 x min-1 of isosorbide dinitrate infusion, but it recovered to the control level at the end of administration of isosorbide dinitrate. Heart rate was unchanged with intravenous isosorbide dinitrate during anesthesia and surgery in both groups, except a mild increase at the end of isosorbide dinitrate infusion of 1 microgram.kg-1 x min-1. Arterial blood oxygen tension showed no decrease during the administration of isosorbide dinitrate and no adverse reactions associated with administration of the drug was detected in this study. Significant improvement of ischemic changes on ECG tracings were observed in about 25% of the patients who received 1 micrograms.kg-1 x min-1 of intravenous isosorbide dinitrate.

[Effects of sevoflurane anesthesia on dopamine metabolism in the rat brain]

To elucidate the mechanism of general anesthesia, effects of sevoflurane anesthesia on dopamine metabolism in rat brain were studied. Sevoflurane 3% was administered for 20 minutes to Wistar male rats weighing 230-270 g under spontaneous respiration. The rats were sacrificed by decapitation and the brains were rapidly removed. They were dissected into nine discrete regions, locus coeruleus, pons plus, medulla oblongata, hypothalamus, thalamus, basal ganglia, midbrain, hippocampus, amygdala and cerebral cortex. The contents of dopamine (DA) and its major metabolites, 3, 4-dihydroxyphenyl acetic acid (DOPAC) and homovanillic acid (HVA) were measured by high performance liquid chromatography with the dual-cell coulometric detector before anesthesia, 20 minutes after the start of anesthesia and at the recovery from anesthesia. Significant increases in DA levels were observed in the pons, hypothalamus, thalamus and amygdala by sevoflurane anesthesia as compared with the control group. DOPAC levels increased significantly in the pons, hypothalamus, basal ganglia and cerebral cortex at the recovery from anesthesia. A significant increase in HVA levels was observed in amygdala by sevoflurane anesthesia, while an appreciable decrease in HVA levels was observed in hippocampus at recovery from anesthesia. It is concluded that DA metabolism is significantly suppressed in the pons, hypothalamus, thalamus, basal ganglia, midbrain and amygdala during sevoflurane anesthesia and this change in DA metabolism may be associated with the mechanism of sevoflurane anesthesia.

[Pharmacokinetics of ketamine and pentazocine during total intravenous anesthesia with droperidol, pentazocine and ketamine]

Pharmacokinetics was studied in ten surgical patients who underwent various operative procedures of about 4 hours under total intravenous anesthesia with droperidol, pentazocine and ketamine (DPK). Plasma levels of ketamine, its metabolites and pentazocine were determined thirteen times during and after DPK. During anesthesia, ketamine (KO) and norketamine (KMI) levels ranged from 0.7 to 1.0 micrograms.ml-1 and from 0.09 to 0.74 micrograms.ml-1, respectively. A small amount of dehydronorketamine (KM II) was detected only 90 min after the start of DPK anesthesia. Plasma half-lives of ketamine were calculated to be 33 min for distribution phase (alpha phase) and 60 min for elimination phase (beta phase), respectively. Pentazocine levels decreased 300 min after the induction of DPK to 10% of the control level measured 5 min after its injection. Plasma half-lives of pentazocine were 60 min for alpha phase and 140 min for beta phase, respectively. The data obtained in this clinical study show that pharmacokinetics of ketamine during DPK is almost similar to that of DFK.

[Effect of M1 blocker or H2 blocker on gastric secretion during anesthesia and surgery]

Effect of pirenzepine, famotidine or a combination of both agents on gastric secretion during anesthesia and surgery was evaluated in 42 surgical patients ranged in age from 17 y to 70 y. They underwent orthopedic, ophthalmic, ENT, plastic, oral or non-abdominal surgery under either neuroleptanesthesia or enflurane anesthesia. They received either pirenzepine 10 mg, famotidine 20 mg or the combination of both agents intravenously just before the induction of anesthesia. Volume and acidity of gastric juice were measured during 3 hours after the administration of these agents. A continued decrease in volume and acidity of gastric juice was observed 3 hrs after the administration of the agents both in the pirenzepine group and in the famotidine group. Efficacy of the combination of pirenzepine and famotidine on gastric secretion tended to be more prominent than that of either pirenzepine or famotidine alone.