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F Kunimoto

Publications and source records attributed to F Kunimoto.

33 records · Page 2Linked to original sources
PubMed1997

Availability of nasal mask BiPAP systems for the treatment of respiratory failure after cardiovascular surgery.

BACKGROUND: The availability of nasal mask bi-level positive airway pressure (BiPAP) support in managing respiratory failure following cardiovascular surgery was studied. MATERIALS AND METHODS: BiPAP support was used for eight patients requiring postoperative prolonged respiratory support of 72 hours or longer. Their mean age was 65 years of age and the mean periods of postoperative endotracheal intubation was 12+/-5 days. BiPAP support was removed within 48 hours in six out of eight patients. Reintubation of an endotracheal tube was not necessary in all eight patients after the BiPAP treatment. RESULTS: The respiratory rates during the BiPAP management remained unchanged. The values of the respiratory index significantly (p<0.01) improved after BiPAP management (1.5+/-0.2 --> 0.9+/-0.2). A-aDO2 and Qs/Qt decreased (p<0.1) after the BiPAP management. There were no significant differences in central venous pressure and circulatory states during BiPAP support. CONCLUSIONS: In conclusions, BiPAP support is a noninvasive management technique for postoperative respiratory failure and may also prevent prolonged endotracheal intubation.

Aged↗
PubMed1996

Impairment of the brain beta-adrenergic system during experimental endotoxemia.

Brain dysfunction is observed clinically in patients suffering from prolonged endotoxic shock. However, the etiology of brain dysfunction during sepsis is not clear. Certain researchers have reported that the decrease in brain catecholamines concentration during septic shock might be etiologically important in brain dysfunction. Therefore, we hypothesized that the beta-adrenergic receptor system undergoes a change during septic shock, and plays a role in the pathogenesis of septic encephalopathy. In this study, we examined two models of septic shock in rats, each of which has a different time course for the shock state. Male Wistar rats were divided into four groups: (1) Control--0.9% saline vehicle, (2) Lipopolysaccharide (LPS) i.v.-- Escherichia coli endotoxin 1.0 mg/ml i.v. bolus, (3) Sham-operated, and (4) Cecal ligation and puncture (CLP) model. The rats were killed by decapitation at 3, 12, or 24 hr after the treatments, and the brains were removed and subdivided into three areas: the forebrain, cerebellum, and brain stem. In the LPS i.v. group, the brain tissue norepinephrine (NE) concentration had decreased in the forebrain and brain stem and the tissue epinephrine (E) concentration had decreased in the brain stem by 3 hr after treatment. In the CLP group, the brain tissue NE concentration had decreased in the forebrain, cerebellum, and brain stem (P < 0.05), and the tissue E concentration had decreased in the forebrain and brain stem by 24 hr after treatment (P < 0.05). An alteration in beta-adrenergic receptor density in the forebrain was observed at 24 hr in the CLP group (control, 237.0 +/- 14.0 fmole/mg protein; LPS i.v., 233.2 +/- 3.0 fmole/mg protein; sham-operated, 236.0 +/- 3.0 fmole/mg protein; CLP, 177.0 +/- 4.2 fmole/mg protein). These alterations in transmitter concentrations and beta-adrenergic density in the forebrain may be an important factor in septic encephalopathy.

Animals↗
PubMed1996

Gastric intramucosal pH and hepatic venous oximetry after cardiopulmonary bypass in valve replacement patients.

To determine splanchnic perfusion after cardiopulmonary bypass, gastric intramucosal pH (pH(i)) and hepatic venous oxygen saturation (SHVO2) were measured in 14 patients with cardiac valve replacement. Blood samples were analysed at 6, 12 and 24 h after admission to an intensive care unit. Gastric pH(i) increased significantly (P < 0.01) from 7.21 at 6 h to 7.31 at 12h and increased to 7.37 at 24 h while SHVO2 increased significantly (P < 0.05) from 48% at 6 h to 57% at 12 h and 24 h. Cardiac index was > 4 l/min per m2 and mixed venous oxygen saturation > 70%. Despite sufficient cardiac output, splanchnic perfusion decreased after cardiopulmonary bypass and recovered within 24 h after admission to the intensive care unit. It is concluded that gastric pH(i) and SHVO2 are useful parameters for monitoring postoperative splanchnic perfusion in patients with open-heart surgery.

Acid-Base Equilibrium↗
PubMed1996

Immediate application of hyperbaric oxygen therapy using a newly devised transportable chamber.

A transportable hyperbaric chamber called the Gamow bag has been reported as an effective means of treating high-altitude illness. The pressure limit of the original bag is set at 2 psi because of the fragility of the fabric. However, improvement of the hardware to make the bag capable of withstanding higher pressures has made it possible to perform standard hyperbaric oxygen therapy with the newly devised portable chamber, the Chamberlite 15. In this study, the safety of the new bag was examined using healthy human volunteers, and the bag was shown to be usable in clinical emergency cases, such as CO intoxication and decompression sickness. The effectiveness of emergency hyperbaric oxygen therapy was also examined using the CO intoxication model of the rat. It was suggested that hyperbaric therapy was especially beneficial if applied during the first 30 minutes of rescue work. It was concluded that the transportable chamber was a promising emergency tool for CO intoxication.

Animals↗
PubMed1996

[Comparison of the effects of halothane, isoflurane and sevoflurane in the treatment of severe asthmatic attack: a case report].

A 19-year-old woman suffered from a severe asthmatic attack. She did not respond to any of the conventional therapies and eventually lapsed into a state of unconsciousness. We administered isoflurane 1-2% via an endotracheal tube, but, she still required a ventilator. This study was carried out in order to compare the effects of halothane, isoflurane and sevoflurane in the treatment of a severe asthmatic patient. The inhalation of isoflurane, halothane and sevoflurane decreased the airway resistance and systemic vascular resistance in direct relationship to the dosage administered. Because the patient's metabolic rate is low and the occurrence of arrhythmias is rare with isoflurane, we concluded that isoflurane is the best alternative for the patient with asthma.

Adult↗
PubMed1996

[Changes in gastric intramucosal pH and hepato-splanchnic oxygen extraction ratio after heart surgery].

The Do2/VO2 balance of splanchnic organs after heart surgery was evaluated using two different methods; the measurement of hepato-splanchnic oxygen extraction ratio (OERspl) and gastric intramucosal pH (pHi) employing a hepatic venous catheter and a gastric tonometric catheter. Systemic oxygen extraction ratio was within normal ranges during the 24 hours of the experiment, but pHi decreased and OERspl increased significantly at 6 hours after admission to the ICU. Both pHi and OERspl returned gradually to normal levels after 24 hours. We conclude that a period of 24 hours is required to restore sufficient blood flow in the visceral organs to meet oxygen demand and that the pHi reflects the splanchnic DO2/VO2 balance as well as OERspl.

Adult↗
PubMed1995

Extracorporeal membrane oxygenation for respiratory failure.

We report herein our experience with extracorporeal membrane oxygenation (ECMO) for respiratory failure over a 3-year period. ECMO was employed in seven patients: in five for respiratory failure caused by adult respiratory distress syndrome (ARDS), Goodpasture's syndrome, hypoxia after ventricular septal defect closure, interstitial pneumonia, or lung metastasis from choriocarcinoma; and in two for tracheal obstruction. Nafamostat mesilate was used as the main anticoagulant with a small amount of heparin. The period of ECMO support for the five patients with respiratory failure ranged from 54 to 251 h, with an average time of 125 h. Five of the seven patients were able to be weaned from ECMO, and the two who had tracheal obstruction survived. The other three patients who were weaned from ECMO died of underlying diseases or complications 1-25 days after weaning. The complications which occurred during ECMO support were an abnormal electroencephalogram, multiple organ failure, and mediastinitis. Thus, we conclude that ECMO needs to be induced early to obtain a better outcome in patients with respiratory failure, and that it is particularly effective for transient airway obstruction.

Adult↗
PubMed1995

[Hemodynamic effects of amrinone on patients with moderate and severe cardiac dysfunction after open heart surgery].

Hemodynamic effects of amrinone and the changes in pulmonary shunt were studied in patients for open heart surgery. Eighteen patients were allocated into two groups (group L, H) on the first day of surgery. Group L consisted of 10 patients who received moderate-dose catecholamine (DOA + DOB < 12 micrograms.kg-1.min-1) and group H consisted of 8 patients who needed high-dose catecholamine (DOA + DOB > or = 12 micrograms.kg-1.min-1) to maintain normal hemodynamics. After baseline measurement, amrinone infusion was started and the dose was increased by every 2 hours (5, 10, 20 micrograms.kg-1.min-1). At dose of 20 micrograms.kg-1.min-1, cardiac index increased significantly in group L but not in group H. SVRI and PVRI decreased by dose related fashion in both groups. Systemic arterial pressure was unaltered in group L while it decreased significantly in group H. PaO2 decreased and pulmonary shunt increased in both groups. These results suggest that inotropic response of amrinone depends on the basal level of myocardial contractility although vasodilative property and the effect on the pulmonary shunt are almost similar in both groups.

Adult↗
PubMed1989

Exacerbation of hypercapnia and acidosis of central venous blood and tissue following administration of sodium bicarbonate during cardiopulmonary resuscitation.

Administration of sodium bicarbonate during cardiopulmonary resuscitation (CPR) is controversial, and our aim was to elucidate whether or not its administration is beneficial by analyzing the acid-base status and the level of carbon dioxide in central venous blood during CPR, and their changes following administration of sodium bicarbonate. Six patients were studied. They had all been admitted to the intensive care unit (ICU), had already had pulmonary arterial or central venous catheters inserted, and had acute episodes of circulatory collapse during their stay in the ICU. The following phenomena were observed: 1) hypercapnia and acidosis of central venous blood were prominent during both cardiogenic shock and CPR, although arterial hypocapnia was maintained by hyperventilation; 2) administration of sodium bicarbonate during cardiogenic shock and CPR induced exacerbation of hypercapnia and acidosis of central venous blood; 3) when arterial hypercapnia was present due to disturbed ventilation, administration of sodium bicarbonate exacerbated hypercapnia and acidosis of both arterial and central venous blood; 4) administration of sodium bicarbonate did not induce hypercapnia of central venous blood in a septic shock patient in whom the septic hyperdynamic state was prevalent in spite of low systemic perfusion pressure. It was concluded that hypercapnia and acidosis of the central venous blood and tissues were exacerbated by administration of sodium bicarbonate during CPR, and that such an effect might be dependent on the severity of the decrease in tissue perfusion.

Acid-Base Equilibrium↗
PubMed1987

Inhibition of lipid peroxidation improves survival rate of endotoxemic rats.

The accumulation of lipoperoxide (LPO) is reported to occur in the organs of animals with endotoxemia, where it is accompanied by an activation of xanthine oxidase (XOD) and a depletion of superoxide dismutase (SOD). In the present study, three measures of preventing LPO accumulation, ie, prior treatment with a XOD inhibitor, exogenous supply of enzymatic scavengers, and supplementation with chemical quenchers, were investigated to determine how to improve the survival rate of rats with lethal endotoxemia. Thirty minutes after treatment with various doses of allopurinol, SOD, catalase (CAT), vitamin E (VE), and reduced glutathione (GSH), adult male Wistar rats were subjected to endotoxemia by an intraperitoneal injection of 0.4 mg/100 g of Escherichia coli endotoxin. Allopurinol did not improve survival rates, denoting a lower level of XOD and an almost normal level of SOD in the liver. SOD (9,000 U/100 g) with or without CAT (4,000 U/100 g) markedly increased the survival rate of rats, with complete inhibition of hepatic LPO accumulation and suppression of XOD activity. CAT alone had no salutary effects on survival rate or hepatic LPO. Large amounts of VE (100 mg/100 g) or GSH (50 mg/100 g) slightly suppressed the accumulation of LPO in the liver but had no effect on survival rate. In that exogenous SOD has been considered not to penetrate the cellular membrane because of its high molecular weight, the results suggest that the extracellular spaces are the site of SOD action. Lipid peroxidation of the biomembrane initiated by oxygen free radicals released into extra-cellular space from phagocytes may play an important role in the development of lethality in experimental endotoxemia.

Allopurinol↗
PubMed1982

Changes in hepatic lipoperoxide concentration in endotoxemic rats.

Wistar strain rats were treated with E. coli endotoxin by intraperitoneal injection (1 mg/100g body weight). Three hours after injection, the livers were excised to determine lipoperoxide concentration and superoxide dismutase activity. A significant elevation of lipoperoxide concentration and a marked reduction of superoxide dismutase activity were observed. Treatment with xanthine oxidase inhibitor were observed. Treatment with xanthine oxidase inhibitor allopurinol (10 mg/100g) 20 minutes prior the injection of endotoxin inhibited the elevation of lipoperoxide and the reduction of superoxide dismutase induced by endotoxin. Pretreatment of free radical scavengers such as reduced glutathione and alpha-tocopherol prevented the accumulation of lipoperoxide in the liver. Reduced glutathione protected the hepatic superoxide dismutase from decrease by endotoxin treatment. However, alpha-tocopherol did not maintain liver superoxide dismutase activity following the injection of endotoxin. These results indicate that endotoxemia gives rise to the accumulation of hepatic lipoperoxide by the activation of a production system and impairment of an elimination system of superoxide radicals.

Allopurinol↗
PubMedDate not supplied

Noninvasive nasal mask BiPAP management for prolonged respiratory failure following cardiovascular surgery.

The purpose of this study was to assess the efficacy of nasal mas bi-level positive airway pressure (BiPAP) support in managing respiratory failure following cardiovascular surgery. A total of 20 patients requiring postoperative prolonged respiratory support of 72 hours or longer were studied. BiPAP support was used for eight patients (BiPAP group); the other 12 patients were managed using ordinary oxygen mask treatment (control group). The mean age of the BiPAP group and control group was 65 and 58 years of age, respectively. The mean period of postoperative endotracheal intubation of the BiPAP group and control group was 12 +/- 5 days and 7 +/- 1 days, respectively. Reintubation was necessary in two patients of the control group. The BiPAP group patients required no reintubation. BiPAP support was discontinued within 48 hours in 6 out of 8 patients. The respiratory rates of control group increased (p < 0.1) 24 hours after extubation, however, the respiratory rates of the BiPAP group remained unchanged. The values of the respiratory index of the BiPAP group improved significantly (p < 0.01) after BiPAP management (from 1.5 +/- 0.2 to 0.9 +/- 0.2). The values of the control group, however, remained unchanged. A-aDO2 and Qs/Qt decreased (p < 0.1) in the BiPAP group. There were no significant differences in central venous pressure or circulatory status between the two groups. In conclusion, BiPAP support is a noninvasive management technique for postoperative respiratory failure and may also prevent prolonged endotracheal intubation.

Aged↗
PubMedDate not supplied

Impaired blood rheology in critically ill patients in an intensive care unit.

Critically ill patients are at increased risk of thromboembolic complications. Japanese patients admitted to the intensive care unit of Gunma University Hospital were divided into critically ill (high score) and moderately ill (low score) groups according to mean Acute Physiology and Chronic Health Evaluation (APACHE) II score. White blood cell count, potassium, creatinine, immunoglobulin G and blood passage time, measured using the microchannel method, were significantly higher and the platelet aggregation score and platelet count were significantly lower in the high-score group than in the low-score group, but other haemorheological parameters did not differ significantly between the two groups. White blood cell count, potassium, creatinine, APACHE II score and levels of immunoglobulins G, A and M were positively correlated with blood passage time in all patients. Critically ill patients had impaired blood rheology, which could result from increased white blood cell count, potassium, creatinine and immunoglobulins and may be associated with the pathophysiology of the thromboembolic process.

Adolescent↗