Impaired oxygenation during sleep at high altitude in Sherpa.

Arterial oxygenation during sleep in Sherpa highlanders has been relatively unexplored. This study was designed to investigate arterial oxygen saturation (Sa(O(2))) and pulse rate (PR) during sleep in 61 Sherpa (29 men, 32 women) who had lived at 3,450-3,850 m in Nepal, from adolescence through old age, and to estimate the relative effects of aging on arterial oxygenation during sleep. The mean Sa(O(2)) during sleep (mSa(O(2))) was found to decrease with age, and to negatively correlate with the mean PR during sleep.

Volume acceleration as an index of respiratory drive during exercise.

In order to evaluate the applicability of volume acceleration (A(I)) at the onset of inspiration as an index of neuromuscular output, CO(2) rebreathing in six healthy subjects and incremental-load exercise in eight healthy subjects was performed while measuring A(I) and mouth occlusion pressure (P(0.1)). During CO(2) rebreathing, A(I) increased linearly with end-tidal CO(2) partial pressure and P(0.

Control of upper airway function in response to hypoxia in patients with obstructive sleep apnea syndrome.

To clarify the characteristics of upper airway muscles under hypoxic condition in obstructive sleep apnea syndrome (OSAS), we performed the isocapnic progressive hypoxia test during wakefulness in 8 controls and 7 OSAS patients. Electromyographic activities were recorded from the genioglossal muscle (EMG(GG)) and diaphragm (EMG(DIA)) with ventilatory variables. Minute EMG (peak integrated EMG x respiratory rate) activity against P(ET)O2 was calculated by exponential equation, and its response slope represented the hypoxic sensitivity of each muscle, slope(GG) and slope(DIA).

Compensatory excretion of prostacyclin and thromboxane metabolites in obstructive sleep apnea syndrome.

Since obstructive sleep apnea syndrome (OSAS) is often linked with systemic hypertension, we sought to clarify the characteristics of prostanoid metabolism in OSAS. In 7 OSAS patients (apnea-hypopnea index, 51.0 +/- 23.

[Alpha 1-antitrypsin deficiency with bronchiectasis in two sisters].

Two sisters with alpha 1-antitrypsin deficiency and bronchiectasis are reported. The 53-year-old older sister (propositus) had pneumonia 3 times during her forties. She developed dyspnea on exertion in February, 1988, and a few months later she was seen at our hospital.