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Fumio Nishihara

Publications and source records attributed to Fumio Nishihara.

8 recordsLinked to original sources
PubMed2006

Carbon dioxide exhalation temporarily increases during electroconvulsive therapy.

Electroconvulsive therapy induces hypermetabolism and elevates oxygen and energy demands, while more carbon dioxide is produced than usual. The purpose of the present study was to determine the elevated carbon dioxide exhalation and the adequate ventilation volume during electroconvulsive therapy. Carbon dioxide exhalation during an electrically induced seizure was continuously monitored by capnography and spirography in 15 patients with endogenous depression. A laryngeal mask airway was used to measure the airway gas flow. Data were collected during a total of 80 electroconvulsive therapy trials. The carbon dioxide exhalation at 1 min after electrical stimulation was higher than the control value (2.8 +/- 0.4 versus 2.3 +/- 0.3 ml.min(-1).kg(-1), mean +/- SD; P < 0.05). The ventilation volume was increased for 3 min after the electrical stimulation to maintain the end-tidal carbon dioxide partial pressure at 35-40 mmHg. The results showed that increasing the ventilation volume by approximately 20% may be necessary to compensate for the increased carbon dioxide exhalation during electroconvulsive therapy.

Adult↗
PubMed2005

Landiolol and esmolol prevent tachycardia without altering cerebral blood flow.

PURPOSE: Several ss-adrenergic-blocking drugs have been used during electroconvulsive therapy (ECT) to stabilize the hemodynamic alterations following electrical stimulation. The effects of two ultra-short acting ss-adrenergic-blocking drugs, esmolol and landiolol, on systemic and cerebral circulation were studied during ECT. METHODS: In the first study (n = 15), dose-dependent hemodynamic changes were studied when landiolol was administered immediately after induction of anesthesia. In the second study (n = 12), effects of esmolol and landiolol on systemic and cerebral circulation were compared. Patients in Study 1 received three doses of landiolol, and patients in Study 2 received two types of ss-adrenergic-blocking drugs, in a randomized cross-over design in a series of ECT trials. RESULTS: In the first study, 0.25 to 0.5 mg.kg(-1) landiolol induced a lower heart rate after the electrical stimulation compared to vehicle (P < 0.01). Landiolol did not have significant effects on blood pressure. In the second study, heart rate was stabilized by 1.0 mg.kg(-1) esmolol iv or 0.5 mg.kg(-1) landiolol iv. Increase in mean blood pressure was ameliorated by esmolol (P < 0.01), but not by landiolol. Mean cerebral blood flow velocity in the middle cerebral artery increased at one to two minutes after the electrical stimulation regardless of the use of ss-adrenergic-blocking drugs (P < 0.01). Muscular and electroencephalographic seizure durations were not significantly altered by the ss-adrenergic-blocking drugs. CONCLUSION: Landiolol suppresses heart rate elevation during ECT without affecting blood pressure. Cerebral blood flow velocity in the middle cerebral artery is not affected by the use of either esmolol or landiolol.

Adrenergic beta-Antagonists↗
PubMed2005

Relationship between arterial oxygen saturation and heart rate variability at high altitudes.

Autonomic nervous systems have important roles for survival of victims under hypobaric hypoxic condition. In the present study, we assessed the correlation between arterial oxygen saturation (Sp O 2 ) and heart rate variability (HRV) to identify the autonomic nervous responsiveness among trekkers at high altitude (n = 21). HRV was analyzed by the maximum entropy method. Sp O 2 among subjects at 3456 m (495 mm Hg) was 80% +/- 5% (mean +/- SD; range, 69%-93%). Sp O 2 and percentile entropy, and Sp O 2 and low-frequency variability, had positive correlation ( r = 0.455 and 0.518, respectively). Sp O 2 value among subjects with mountain sickness symptoms was not different from that among subjects without the symptoms. In conclusion, autonomic responses among high-altitude trekkers may be blunted under hypobaric hypoxic conditions. Deterioration of autonomic function measured by HRV might be more sensitive to hypoxia than clinical symptoms at high altitudes.

Adult↗
PubMed2003

Benefits of the laryngeal mask for airway management during electroconvulsive therapy.

Accumulation of carbon dioxide (CO2) can disturb systemic hemodynamics and increase the seizure threshold in patients receiving electroconvulsive therapy (ECT). The purpose of this study was to investigate the effects of the laryngeal mask on blood gas, hemodynamics, and seizure duration during ECT under propofol anesthesia. Ventilation was assisted using either a face mask (n=23) or laryngeal mask (n=23) and 100% oxygen. There was no significant difference in PaO2 between the two groups. PaCO2 was greater in the face mask group than the laryngeal mask group at 3 minutes (54 +/- 11 mm Hg, 41 +/- 8 mm Hg, respectively) and 5 minutes (52 +/- 11 mm Hg, 43 +/- 15 mm Hg, respectively) after electrical stimulation (p<0.01). Mean blood pressure was higher than the corresponding preanesthesia value at 1 to 5 minutes after electrical stimulation in the face mask group and at 1 to 3 minutes after electrical stimulation in the laryngeal mask group. Mean seizure duration in the face mask group was significantly shorter than that in the laryngeal mask group (33 +/- 11 seconds, 42 +/- 10 seconds, respectively p<0.01). The change in PaCO2 was minor in the laryngeal mask group compared with the face mask group and seizure duration was longer in the laryngeal mask group. Laryngeal mask may be suitable for airway management during ECT anesthesia, especially when fitting a face mask is difficult.

Adult↗
PubMed2002

G-protein coupled receptor kinase 2 is altered during septic shock in rats.

BACKGROUND: One of the key mechanisms leading to beta-adrenergic receptor-specific desensitization is the phosphorylation of agonist-occupied receptors by the specific beta-adrenergic receptor kinase (GRK2). The present study examines whether GRK2 is altered during septic shock in rats. MATERIALS AND METHODS: Male Wistar rats (7 weeks) weighing between 250 and 300 g were anesthetized with pentobarbital (10 mg/kg ip). Escherichia coli endotoxin (10 mg/kg in 0.3 mL of saline) or saline (0.3 ml) was injected intravenously via the dorsal vein. Hemodynamic parameters and humoral mediators were measured at 2 h after the administration of endotoxin. The hearts were immediately excised to examine beta-adrenergic receptor density and GRK2 level. We also studied the inotropic response to isoproterenol at the same time in other animals. RESULTS: Myocardial beta-adrenergic receptor density in the membrane fraction was decreased after an intravenous administration of 10 mg/kg LPS (LPS group: baseline value; 82 +/- 11 fmol/mg protein; 120 min after LPS; 58 +/- 11 fmol/mg protein, P < 0.05). GRK2 levels in the membrane and cytosolic fraction of the control group did not change. In the LPS group, GRK2 levels in the membrane fraction were increased at 60 and 120 min after the treatment (60 min; control, 4.5 +/- 0.4; pithed control, 4.4 +/- 0.6; LPS group, 6.2 +/- 0.3; pithed LPS group, 5.5 +/- 0.4; 120 min: control, 4.4 +/- 0.3; pithed control, 4.9 +/- 0.7; LPS group, 7.1 +/- 0.3; pithed LPS group, 5.9 +/- 0.4; densitometric unit, respectively: P < 0.05). CONCLUSIONS: GRK2 levels in the membrane fraction are increased during septic shock in rats. GRK2 might play a role in the impairment of the beta-adrenergic receptor signal transduction system.

Adrenergic beta-Agonists↗
PubMed2002

Physical condition among middle altitude trekkers in an aging society.

The number of alpine accidents has markedly increased among elderly trekkers in an aging society, Japan. We evaluated the physical condition of 176 trekkers by interview and physical examination on a popular middle altitude mountain. Heart rate, noninvasive blood pressure and arterial oxygen saturation (SpO2) were measured using a portable life monitor. It was revealed that more than 70% of the trekkers were over 50. Seventy-five percent of trekkers over 70 had some pre-existing medical problems. Systolic and diastolic blood pressure before the start of trekking, increased with age. However, such age-dependent differences were not apparent at the summit hut. SpO2 values decreased slightly but significantly with age. In conclusion, many elderly people enjoy nonchallenging middle altitude trekking in an aging society. Alpine accidents caused by health problems tend to arise more frequently in this population. Alpine rescue teams should be well-prepared for the alpine accidents of elderly trekkers.

Adolescent↗
PubMed2002

Pre-ictal bispectral index has a positive correlation with seizure duration during electroconvulsive therapy.

UNLABELLED: Propofol anesthesia increases the seizure threshold of patients receiving electroconvulsive therapy. Excessive neuronal suppression could result in an unacceptably short seizure. We sought to identify the correlation between the pre-ictal bispectral index (BIS) score and seizure duration in patients receiving electroconvulsive therapy under propofol anesthesia. BIS was monitored in 38 psychotically depressed patients. Anesthesia was induced by a bolus injection of 1 mg/kg of propofol. The duration of muscular and electroencephalographic seizure was measured during the therapy. The BIS immediately before the electrical shock was 54 +/- 13. Both muscular and electroencephalographic seizure durations had a positive correlation with pre-ictal BIS (r = 0.68 and 0.73, respectively; P < 0.01). After the electrically induced seizure, BIS decreased to 30 +/- 8, reflecting post-ictal suppression. BIS scores when the patients had awakened after the seizure had a wide variation (range, 29-81; mean, 45; SD, 13). In conclusion, seizure duration has a positive correlation with BIS immediately before electrical shock; however, BIS may not be an accurate predictor of awakening after electrical shock. IMPLICATIONS: Pre-ictal bispectral index had a positive correlation with seizure duration and could be useful to prevent an unacceptably short seizure in electroconvulsive therapy under propofol anesthesia.

Adult↗