Hyperthermia during prolonged exercise leads to hyperventilation, which can reduce arterial CO2 pressure (PaCO2 ) and, in turn, cerebral blood flow (CBF) and thermoregulatory response. We investigated 1) whether humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise and 2) the effects of voluntary breathing control on PaCO2 , CBF, sweating, and skin blood flow. ...

Since methotrimeprazine proved to be both an effective tranquilizer and analgesic, its effect in a tranquilizing dose of 0.15 mg/kg on the arterial blood gases was determined in human volunteers. Because of the known potentiating effect of some phenothiazines on the narcotic-analgesic induced respiratory depression and analgesia, the effect of methotrimeprazine on the meperidine-induced respira...

1. In 12 unselected outpatients with chronic obstructive pulmonary disease and six controls, arterial pH, PaO2, PaCO2 and oxygen saturation (SaO2), forced expiratory volume in 1.0 s (FEV1.0) and vital capacity were measured. Subjects were grouped into those with or without obstruction based on the Tiffenau index. The Baseline Dyspnoea Index was employed to objectify the severity of dyspnoea and...

STUDY OBJECTIVES The degree and duration of respiratory stimulation of medroxyprogesterone acetate (MPA) in postmenopausal women. DESIGN A placebo-controlled single-blind trial. SETTING University hospital in Turku, Finland. PATIENTS Fourteen postmenopausal women with permanent or previous episodic hypercapnic or hypoxemic respiratory failure. INTERVENTIONS A 12-week trial including 14-...

UNLABELLED BACKGROUND AND METHDS: Alveolar recruitment maneuver (ARM) is indicated in the treatment of intraoperative atelectasis. The objective of the present study was to compare two techniques of ARM using the response of the PaO2/FiO2 ratio and [PaO2 + PaCO2] in patients with grade III obesity. METHODS This was an open prospective study with adult patients with grade III obesity who under...

Inactive forearm muscle oxygenation has been reported to begin decreasing from the respiratory compensation point (RCP) during ramp leg cycling. From the RCP, hyperventilation occurs with a decrease in arterial CO2 pressure (PaCO2). The aim of this study was to determine which of these two factors, hyperventilation or decrease in PaCO2, is related to a decrease in inactive biceps brachii muscle...

This study examined the role of alterations in the chemoreflex control of breathing, acidbase balance and their interaction in postmenopausal ventilatory adaptations. A modified iso-oxic hyperoxicand hypoxic-CO2 rebreathing procedure was employed to evaluate central and peripheral chemoreflex drives to breathe, respectively, in 15 healthy postmenopausal (POST) and 20 premenopausal (PRE) women o...

BACKGROUND Although respiratory exacerbations are common in patients with quadriplegic cerebral palsy (CP), little is known about the factors that are related to increased exacerbation risk. This study aimed to identify the clinical and pulmonary function variables signaling risk of exacerbation in this type of patient. METHODS Thirty-one children and young adults with quadriplegic CP underwe...

The exercising Thoroughbred horse (TB) is capable of exceptional cardiopulmonary performance. However, because the ventilatory equivalent for O2 (VE/VO2) does not increase above the gas exchange threshold (Tge), hypercapnia and hypoxemia accompany intense exercise in the TB compared with humans, in whom VE/VO2 increases during supra-Tge work, which both removes the CO2 produced by the HCO buffe...

Transcutaneous oxygen (TcPo2) and carbon dioxide (TcPco2) tensions were compared with arterial values in 23 children aged 4 months to 14 years, all requiring some form of respiratory support, but not in shock. Electrodes were placed on the upper chest and were heated to 45 degrees C. For TcPo2 and arterial oxygen (Pao2) a tight linear correlation over the range 6 to 14 kPa was found. Arterial c...