Biomedical subjects

T Iwakawa

Publications and source records attributed to T Iwakawa.

12 recordsLinked to original sources

PubMed2001

Daily changes of the area of density in the dependent lung region - evaluation using transesophageal echocardiography.

OBJECTIVE: To evaluate the daily changes of the area of density using transesophageal echocardiography (TEE) in acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) patients. DESIGN: Retrospective observational study. SETTING: General ICU in a university hospital. PATIENTS: Fifteen patients with ARDS or ALI who underwent TEE examination for more than 5 days. MEASUREMENTS: Densities in the lower left lung region were observed through the descending aorta by TEE. Daily changes of the area of density were evaluated. The areas of density estimated by TEE were compared with those obtained by computed tomography (CT). The relation between the area of density and PaO(2)/FIO(2)was calculated. RESULTS: The area of density in the dependent lung region measured by TEE was 11.1+/-5.7 cm(2) (mean +/- SD) at the mid-esophageal position. The area of density in ARDS patients changed daily from 12.0+/-2.8 cm(2) to 8.5+/-6.7 cm(2). The areas of density evaluated using TEE in the left lung correlated significantly with those estimated using CT ( r=0.72, p<0.01). In addition, we found a significant correlation between PaO(2)/FIO(2) and the area of density estimated by TEE ( r=-0.53, p<0.05). CONCLUSION: Using TEE, we could evaluate daily changes of the area of density in the dependent lung region in the intensive care situation. The areas of density in ARDS patients changed from day to day following the changes of oxygenation.

Adult↗

PubMed2001

A new galloylglucoside from Cleyera ochnacea DC.

A new galloylglucoside, 3-hydroxy-5-methylphenol 1-O-beta-D-(6'-galloyl)glucopyranoside (1) was isolated from Cleyera ochnacea DC. (Theaceae). Its structure was elucidated on the basis of chemical and spectral analysis. Compound 1 showed inhibitory activity against rat cerebellar nitric oxide synthase (NOS).

Animals↗

PubMed2000

Reaction of 3-acetonyl-5-cyano-1,2,4-thiadiazole with phenylhydrazine hydrochlorides: indolization and phenylpyrazolation.

Treatment of 3-acetonyl-5-cyano-1,2,4-thiadiazole (1) with 4-methyl or 4-methoxyphenylhydrazine hydrochloride provided 5-cyano-3-(2,5-dimethylindol-3-yl)-1,2,4-thiadiazole (2) or 5-cyano-3-(5-methoxy-2-methylindol-3-yl)-1,2,4-thiadiazole (3) as the sole product, respectively. In contrast, treatment of 1 with phenylhydrazine hydrochloride resulted in the formation of 5-cyano-3-(2-methylindol-3-yl)-1,2,4-thiadiazole (4) and the unexpected 5-cyano-3-(3,5-dimethyl-1-phenylpyrazol-4-yl)-1,2,4-thiadiazole (5). In a similar manner, when 1 was treated with 4-chlorophenylhydrazine hydrochloride, indolization was suppressed by phenylpyrazolation giving rise to 5-cyano-3-(5-chloro-2-methylindol-3-yl)-1,2,4-thiadiazole (6) and 5-cyano-3-[1-(4-chlorophenyl)-3,5-dimethylpyrazol-4-yl]-1,2,4-thia diazole (7). The reaction mechanism is discussed. Compounds 4, 5 and 6 exhibited weak antimicrobial activity against Helicobacter pylori.

Anti-Bacterial Agents↗

PubMed1999

Does indocyanine green accurately measure plasma volume independently of its disappearance rate from plasma in critically ill patients?

OBJECTIVE: To determine whether plasma volume determined by the indocyanine green (ICG) dilution method (PV-ICG) is equally accurate independently of its disappearance rate from plasma in the critically ill. DESIGN: Retrospective clinical investigation. SETTING: Intensive care unit of a university teaching hospital. PATIENTS AND METHODS: 192 adult patients were initially enrolled. The PV-ICG and the initial distribution volume of glucose (IDVG) were calculated utilizing a one-compartment model by simultaneous administration of ICG 25 mg and glucose 5 g on the first day of measurement in each patient. Twenty-one patients were excluded from the study because of a higher PV-ICG/IDVG ratio (> 0.45) indicating apparent overestimation of the PV-ICG associated with the generalized protein capillary leakage. The remaining 171 patients were divided into four groups according to the magnitude of their disappearance rate of ICG from plasma (Ke-ICG). RESULTS: Convergence was assumed consistently in each ICG or glucose decay curve, even in the lower Ke-ICG less than 0.10/min. The relationship between the two volumes was not statistically different among groups. CONCLUSIONS: The results suggest that the measurement of the PV-ICG can be equally accurate independently of its disappearance rate from plasma unless there is generalized protein capillary leakage.

APACHE↗

PubMed1998

Ratio of indocyanine green and glucose dilutions detects capillary protein leakage following endotoxin injection in dogs.

This study was designed to determine whether endotoxin-induced generalized capillary protein leakage can be detected using the ratio of indocyanine green (ICG) and glucose dilutions. Plasma volume determined by the ICG dilution method (Vd-ICG) and the initial distribution volume of glucose (IDVG) were assessed simultaneously before and after either the administration of lipopolysaccharide (LPS) 0.3 mg kg-1 or equal amounts of isotonic saline in two groups of eight dogs, using a one-compartment model after simultaneous infusions of both ICG 0.5 mg kg-1 and glucose 100 mg kg-1. The IDVG has been shown to indicate the extracellular fluid volume of highly perfused organs including plasma. All post-treatment values decreased compared with the pre-treatment values (P < 0.05), except Vd-ICG in the LPS group, even though the post-treatment total plasma protein concentration of the LPS group decreased significantly compared with the pre-treatment value (P < 0.05). The post-treatment Vd-ICG/IDVG ratio of the saline group remained unchanged compared with that of the pre-treatment, and the post-treatment ratio of the LPS group increased significantly (P < 0.01). It can be concluded that overestimation of the Vd-ICG can occur after endotoxin injection, which can be detected by simultaneous measurements of the Vd-ICG and the IDVG.

Animals↗

PubMed1998

Measurements of extracellular fluid volume in highly perfused organs and lung water in hypo- and hypervolaemic dogs.

The purpose of this study was to identify whether the central extracellular fluid volume status following hypo- and hypervolaemia can be measured by the initial distribution volume of glucose or by the extravascular lung water. These two estimates were compared with the initial distribution volume of sucrose which has been used as an indicator for the measurement of the extracellular fluid volume. The above three estimates were determined by the administration of glucose, chilled saline and sucrose solutions, before and after haemorrhage (30 mL kg-1), and subsequent fluid load (lactated Ringer's solution 90 mL kg-1). The distribution volumes of glucose and sucrose decreased after haemorrhage and increased after fluid load compared with normovolaemic values, and a linear correlation was obtained between these two distribution volumes (r = 0.93, P < 0.001, n = 36). However, the extravascular lung water remained statistically unchanged throughout the procedure, despite a weak linear correlation with the sucrose distribution volume (r = 0.38, n = 33, P < 0.05). These results indicate that the initial distribution volume of glucose is more useful as an indicator of the central extracellular fluid volume status than the extravascular lung water.

Animals↗

PubMed1994

[Changes in rectal temperature during tympanoplasty under general anesthesia].

We measured rectal temperature of 35 patients who underwent tympanoplasty under various types of general anesthesia. They were allocated at random to three groups according to the types of general anesthesia; 10 patients of enflurane-N2O (enflurane group); 10 patients of neuroleptic anesthesia with droperidol, pentazocine-N2O (NLA group); 15 patients of total intravenous anesthesia with droperidol, fentanyl and ketamine (DFK group). After the induction of anesthesia, their rectal temperature was continuously monitored with an electric thermometer of NEC San-ei throughout the surgical procedure. Increase in rectal temperature was observed in all three groups, and increase in DFK group was significant compared with other two groups. It is possible that the significant increase in rectal temperature in DFK group is supposedly due to normally maintained hypothalamic thermoregulatory function as well as direct surgical stimulation to central nervous system.

Adult↗

PubMed1994

[Effect of pirenzepine on gastric secretion during anesthesia and surgery].

Effect of pirenzepine on gastric secretion during anesthesia and surgery was evaluated in 46 surgical patients ranged in age from 18 to 68 years. The patients underwent orthopedic, ophthalmic, ENT, plastic or non-abdominal general surgery under neuroleptanesthesia except two patients who had enflurane or isoflurane anesthesia. They received either pirenzepine 10 mg, 20 mg or the combination of pirenzepine 10 mg and famotidine 20 mg intravenously just before the induction of anesthesia. Volume and acidity of gastric juice were measured for 3 hours after the administration of these agents. Decrease in volume and acidity of gastric juice after pirenzepine 10 mg as well as after pirenzepine 20 mg continued for more than 3 hrs after the administration of the agents. Efficacy of the combination of pirenzepine and famotidine on gastric secretion was more prominent than that of pirenzepine alone in a double dose.

Adolescent↗

PubMed1993

[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.

3-Hydroxybutyric Acid↗

PubMed1993

[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.

Abdomen↗

PubMed1993

[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.

Adult↗

PubMedDate not supplied

Elimination of FK-506 by continuous hemodiafiltration in a liver transplant patient.

A liver transplant patient who developed renal failure postoperatively was treated using continuous hemodiafiltration (CHDF). Doses ranging from 0.01 to 0.06 mg/kg/day of FK-506 had been administered intravenously. FK-506 concentrations before and after the filter, and in the ultradiafiltrate were 45.3 +/- 2.9, 56.0 +/- 5.3, and 9.1 +/- 3.1 ng/ml (mean, +/- S.D.), respectively. The filtration rate was 23.6 +/- 6.4%, and extracted FK-506 amounted to 522.0 micrograms (11.3% of administered dose). A part of the FK-506 administered was eliminated through the filter during CHDF.

Acute Kidney Injury↗