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Katsuyuki Miyasaka

Publications and source records attributed to Katsuyuki Miyasaka.

14 recordsLinked to original sources
PubMed2006

Pediatric anesthesia practice and training in Japan: a survey.

BACKGROUND: Pediatric anesthesia in Japan is in the developing stage. The aim of this study was to review pediatric anesthesia training in Japan and to discuss the future prospects for this field. METHODS: We sent questionnaires to assess current pediatric anesthetic practice and training to all 106 university hospitals [UHs; response rate, 66% (70/106)] and all 17 children's hospitals [CHs; response rate, 87.5% (15/17)] in Japan. We also sent questionnaires to assess attitudes towards pediatric anesthetic training, to all 280 representatives of the Japanese Society of Anesthesiologists [JSA; response rate, 57.9% (162/280)]. RESULTS: The hospital survey revealed the number of pediatric anesthesia cases encountered in 15 CHs (25,009 cases) to be almost equivalent to that in 70 UHs (29,031 cases). In 19 of these UHs, there were no newborn surgical cases. Forty-nine UHs reported that no special training program existed for pediatric anesthesia, and only five UHs mandated training at CHs. Sixty-six percent of the representative JSA members considered it premature for pediatric anesthesia to become a subspecialty, but 87% considered experience in pediatric anesthesia mandatory for anesthesia board qualification. CONCLUSIONS: This survey revealed that although pediatric anesthesia training is considered mandatory, university hospitals lack adequate numbers of pediatric cases and children's hospitals suffer from a shortage of staff positions and anesthesiologists, and hence are unable to satisfy this demand. Most representative members of our society consider it too early to subspecialize pediatric anesthesia in Japan.

Age Factors↗
PubMed2006

Manifestation of mirror syndrome after fetoscopic laser photocoagulation in severe twin-twin transfusion syndrome.

Mirror syndrome is a preeclampsia-like disease first described in a case of severe hydrops fetalis caused by rhesus isoimmunization, later reported in some cases of nonimmunological fetal hydrops. Twin-twin transfusion syndrome (TTTS) is a severe complication associated with monochorionic pregnancies, in particular, severe TTTS with one hydropic fetus leading to a poor prognosis. We report here a case of mirror syndrome that occurred after selective fetoscopic laser photocoagulation in severe TTTS at 24 weeks' gestation.

Adult↗
PubMed2005

Brain tissue oxygenation index measured by near infrared spatially resolved spectroscopy agreed with jugular bulb oxygen saturation in normal pediatric brain: a pilot study.

OBJECTIVES: This observational, prospective pediatric human study was performed to determine the agreement between brain tissue oxygenation indices (TOI) measured by near infrared spatially resolved spectroscopy and jugular bulb oxygen saturation values (SjO(2)). METHODS: Five cardiac patients without neurological impairment who were admitted into the critical care unit after open-heart surgery with jugular bulb venous catheters were enrolled. Their mean age was 8.6 months and mean body weight was 6.7 kg. Simultaneous measurements of brain TOI using NIR0-300 (Hamamatsu Photonics, Hamamatsu City, Japan) and SjO(2) values from blood samples were recorded. RESULTS: The TOI range was 59+/-9% and the SjO(2) range was 58+/-17%. The correlation coefficient R was 0.64 (p=0.11; n=14). Bland-Altman plotting revealed a bias of -3.4%, and precision of 7.2% (n=14). Intra-class correlation reliability analysis showed kappa of 0.55. CONCLUSION: Statistically, brain TOI was in reasonable agreement with SjO(2) in pediatric patients with normal brain within the measurement range from 50 to 70%.

Blood Gas Analysis↗
PubMed2004

Cardiac output measurement by pulse dye densitometry using three wavelengths.

OBJECTIVES: Pulse dye densitometry (PDD), based on the principles of pulse oximetry and dye-dilution technique, is a less invasive method of measuring cardiac output (CO). We have developed prototype equipment to measure CO in pediatric patients using this technique. The purpose of our study was to evaluate the accuracy of this new PDD system using three wavelengths for pediatric application by comparing measurement with an ultrasound flowmeter. DESIGN: Laboratory investigation. SETTING: Hospital physiology research laboratory. SUBJECTS: A total of 15 young piglets weighing approximately 10 kg each. INTERVENTIONS: Measurement of CO by PDD was performed using general anesthesia. Indocyanine green, 0.2 mg/kg, was administered intravenously, and CO was calculated from the dye dilution curve obtained by the PDD system. The ultrasound flowmeter probe was placed on the ascending aorta in the animal, and CO was simultaneously calculated. MEASUREMENTS AND MAIN RESULTS: The two CO values, simultaneously obtained by the ultrasound flowmeter and PDD, were compared during various hemodynamic states. The bias between the CO measured by the ultrasound flowmeter and the CO measured by the PDD system using the reflection-type probe at the central site was 33.8 mL/min and the precision was 293.4 mL/min, indicating that CO measured by PDD had a good correlation with measurements obtained with the ultrasonic method. CONCLUSION: We measured CO in young piglets at an acceptable level of bias and precision using a prototype PDD device. CO measurement by this new PDD system using three wavelengths can be useful and beneficial for critically ill infants and children. It is simple to perform, requiring an injection of dye into a peripheral intravenous catheter, and it will provide a less invasive bedside measurement of CO.

Animals↗
PubMed2004

Prolonged nitric oxide inhalation during recovery from chronic hypoxia does not decrease nitric oxide-dependent relaxation in pulmonary arteries.

STUDY OBJECTIVE: To investigate the effects of long-term nitric oxide (NO) inhalation on the recovery process of right ventricular hypertrophy (RVH) and functional alterations in the NO-cyclic guanosine monophosphate (cGMP) relaxation pathway in rat conduit pulmonary arteries (PAs) in established chronic hypoxic pulmonary hypertension. MATERIALS AND METHODS: A total of 35 rats were exposed to chronic hypobaric hypoxia (380 mm Hg, 10% oxygen), and 39 rats were exposed to air for 10 days. Both groups were then exposed to 3 or 10 days of NO 10 ppm, NO 40 ppm, or air (control groups for each NO concentration), resulting in a total of 16 groups. Acetylcholine- and sodium nitroprusside (SNP)-induced relaxation were evaluated in precontracted PA rings. RVH was assessed by heart weight ratio of right ventricle to left ventricle plus septum. RESULTS: NO inhalation had no effect on either the regression of RVH or the recovery process of impaired relaxation induced by acetylcholine or SNP in a endothelium-intact hypertensive conduit extrapulmonary artery or intrapulmonary artery (IPA). In a normal endothelium-intact conduit IPA, 40 ppm NO inhalation for 10 days partially augmented SNP-induced relaxation, but not that induced by acetylcholine. CONCLUSION: Continuous NO inhalation did not affect the regression process of either established RVH or the impaired endogenous NO-cGMP relaxation cascade in a conduit PA in rats during the recovery period after chronic hypoxia.

Acetylcholine↗
PubMed2003

Pressure-flow relationship and longitudinal distribution of pulmonary vascular resistance in heartworm-infected dogs.

The pressure-flow relationships and the longitudinal distributions of pulmonary vascular resistance in normal and heartworm-infected (HWI) dogs were compared in an isolated, blood perfused preparation. The pulmonary circulation was partitioned into pulmonary arterial, middle, and venous segment based on the concept of a five element lumped model. The pulmonary arterial pressure-flow relationships were found to be non-linear and convex to the pressure axis in both normal and HWI lungs. The pressure-flow relationships of the pulmonary arterial and venous segment were linear and these slopes in the HWI lungs were significantly higher than the normal lungs. The pressure gradient of the middle segment was increased as flow increased at lower flow range, however, it was not increased during higher perfusion range in both lungs. At higher flow, the pressure gradient of the middle segment in the HWI lungs was significantly higher than the normal lungs. These results suggest that the ohmic resistance was almost equal to the sum of the two slopes of the pressure-flow relationships of the pulmonary arterial and venous segment because the pressure gradient of the middle segment was not altered as flow increased during higher perfusion rate. Because the slopes of the pressure-flow relationships of the pulmonary arterial and venous segment were increased with heartworm infection, the ohmic resistance of HWI lungs would be higher than normal lungs. The intercept pressure on the pressure axis of the linear portion of the pulmonary arterial pressure-flow relationship, a critical closing pressure, was regarded as pressure gradient of the middle segment during higher perfusing rate because the intercept pressures of pressure-flow relationships of pulmonary arterial and venous segment were almost equal to zero. Therefore, the critical closing pressure of HWI lungs would be higher than normal lungs. The pulmonary hypertension of filariasis appears to be due to an increase in ohmic resistance and elevated critical closing pressure.

Animals↗
PubMed2002

Pulse oximetry in the management of children in the PICU.

The noninvasive and continuous nature of pulse oximetry is a considerable asset inpatient monitoring in the PICU. Its use in the PICU is constantly challenged by the combined presence of vigorous body motion and poor peripheral circulation, conditions which demand special consideration in developing a better pulse oximeter. This is a point of fierce competition among manufacturers.

Anesthesia↗
PubMed2002

The theory and applications of pulse spectrophotometry.

Opening of the first door of pulse photometry gave us pulse oximeter. The next door opens to multiwavelength pulse photometry. It will give us a high performance pulse oximeter, providing a wide variety of clinical information simultaneously. This next generation of pulse photometry should further improve bedside monitoring and patient care.

Densitometry↗