The objective of the present study was to investigate the possibility of measuring lung tissue oxygen pressure (PtO2) distributions at the microvascular level, and also if a change in the lung tissue oxygenation could be detected during hypoventilation (50% reduction in ventilatory settings). Experiments were carried out on eight mechanically ventilated ketamine-anaesthetised pigs. A thoracotom...

BACKGROUND Non-invasive positive-pressure ventilation (NPPV) is an established, effective, long-term treatment for patients with amyotrophic lateral sclerosis (ALS), but the correct indicators for the establishment of NPPV have not been defined. METHODS In this retrospective study, records (spirometry, nocturnal polygraphy, nocturnal blood gases) of 131 patients with ALS were reviewed in orde...

The aim of the study was to determine the dependence of changes in the electrical stability of the heart on the light-dark cycle (LD cycle) in disorders of pulmonary ventilation. The ventricular arrhythmia threshold (VAT) was measured in female Wistar rats (adaptation to the light regime 12:12 h, ketamine/xylazine anesthesia 100 mg/15 mg/kg, i.m., open chest experiments). The conditions of the ...

OBJECTIVE To identify the spectrum of respiratory disturbances during sleep in patients with obesity hypoventilation syndrome (OHS) and to examine the response of hypercapnia to treatment of the specific ventilatory sleep disturbances. DESIGNS AND METHODS Twenty-three patients with chronic awake hypercapnia (mean [+/- SD] PaCO(2), 55 +/- 6 mm Hg) and a respiratory sleep disorder were retrospe...

Piper AJ, Grunstein RR. Big breathing: the complex interaction of obesity, hypoventilation, weight loss, and respiratory function. J Appl Physiol 108: 199–205, 2010. First published October 29, 2009; doi:10.1152/japplphysiol.00713.2009.— Obesity places a significant load on the respiratory system, affecting lung volumes, respiratory muscle function, work of breathing, and ventilatory control. D...

BACKGROUND High levels of exhaled carbon monoxide (eCO) are a marker of airway or lung inflammation. We investigated whether hypo- or hyperventilation can affect measured values. METHODS Ten healthy volunteers were trained to achieve sustained end-tidal CO2 (etCO(2)) concentrations of 30 (hyperventilation), 40 (normoventilation), and 50 mmHg (hypoventilation). As soon as target etCO(2) values...

BACKGROUND Rapid-onset obesity with hypothalamic dysfunction, hypoventilation and autonomic dysregulation (ROHHAD) is a rare disease with a high mortality rate. Although nocturnal hypoventilation (NH) is central to ROHHAD, the evolution of sleep disordered breathing (SDB) is not well studied. The aim of the study was to assess early manifestations of SDB and their evolution in ROHHAD syndrome. ...

Sleep hypoventilation (SH) may be important in the development of hypercapnic respiratory failure in chronic obstructive pulmonary disease (COPD). The prevalence of SH, associated factors, and overnight changes in waking arterial blood gases (ABG), were assessed in 54 stable hypercapnic COPD patients without concomitant sleep apnoea or morbid obesity. Lung function assessment, anthropomorphic m...

BACKGROUND Sleep disordered breathing (SDB) is common in neuromuscular diseases but its relationship to respiratory function is poorly defined. A study was undertaken to identify distinct patterns of SDB, to clarify the relationships between SDB and lung and respiratory muscle function, and to identify daytime predictors for SDB at its onset, for SDB with continuous hypercapnic hypoventilation,...