Hypocapnia attenuates the sweat response normally seen in hyperthermic resting subjects, but its effect on the blood flow response in their nonglabrous skin under the same hyperthermic conditions remains unclear. In the present study, we investigated whether hypocapnia induced by voluntary hyperventilation affects the blood flow response to heat stress in the nonglabrous skin of resting humans....

The aim of the study was to examine the predisposing and precipitating factors in the development of hyperventilation syndrome in males during military training in Taiwan. The participants included 110 young males who visited the emergency room of a teaching hospital in southern Taiwan because of an episode of acute hyperventilation during military training. Another 53 males, who had the same m...

Pulmonary and systemic arterial carbon dioxide tensions (Pco2) were measured at cardiac catheterization in I.f patients with left-to-right circulatory shunts and in irS patients with valvular heart disease. The measurements were performed under resting conditions and at 5-sec intervals during a 30-sec period of hyperventilation. In both groups the systemic arterial Pco2 fell significantly durin...

Research is reviewed which suggests that hyperventilation syndrome is an underdiagnosed disorder for the presentation of many patients experiencing apparent anxiety states. In a test of this hypothesis, 21 normal individuals (9 female) underwent a 2 min period of intentional hyperventilation following a 10 min baseline phase. Hyperventilation was accompanied by increased subjective anxiety and ...

The precise contribution of the CO2-dependent respiratory rhythm to sinus arrhythmia in eupnea is unclear. The respiratory rhythm and sinus arrhythmia were measured in 12 normal, unanesthetized subjects in normocapnia and hypocapnia during mechanical hyperventilation with positive pressure. In normocapnia (41 +/- 1 mmHg), the respiratory rhythm was always detectable from airway pressure and ins...

Seventy-two healthy young individuals were subjected to controlled, moderate hyperventilation with room air and with 4.9 percent CO2 in air, and monitored electrocardiographically. Significant summed frontal T-wave changes with hyperventilation (sigmaT1,2,3 larger than or equal to 1.5 mm) were observed in 12 patients. Six subjects (8.3 percent) showed T-wave depression. It was reversed in five ...

A recently developed CO2 pulse technique was used to test for ventilatory sensitivity to CO2 in four normal men following 2 min voluntary hyperventilation down to an end-tidal CO2 tension (PETCO2) of 20 mmHg (2.7 kPa). Pure CO2 was injected into the inspiratory limb of a breathing circuit at 0.4 l.min-1 for 30 s and any small ventilatory response was detected against background noise by ensembl...