Arterial blood gas tensions, hydrogen ion, and electroencephalogram during sleep in patients with chronic ventilatory failure.

Overlap syndrome between chronic obstructive pulmonary disease and obstructive sleep apnoea in a Southeast Asian teaching hospital

“…Objective electroencephalography evidence from many studies suggest that there is poor quality sleep in patients with COPD, with long periods of wakefulness contributed to by increased arousals. (38)(39)(40)(41)(42) Similar to our study, the SHHS study also found that, among other things, patients with overlap syndrome had higher AI than patients with obstructive airways disease. (4) Our study also showed that our study cohort, as a whole, had a significantly high PLMI, which again was not a novel finding.…”

Sleep-related O2 desaturation and daytime pulmonary haemodynamics in COPD patients with mild hypoxaemia

“…These results do not support the hypothesis that sleep-related hypoxaemia favours the development of pulmonary hypertension. Eur Respir J 1997;10: 1730-1735 The worsening of hypoxaemia during sleep in patients with chronic obstructive pulmonary disease (COPD) has been documented since the early 1960s [1], and has since been confirmed by polysomnographic studies [2,3], which have included continuous monitoring of oxygen saturation from the late 1970s [4][5][6][7][8][9][10]. It must be emphasized that most of these studies have included patients with severe COPD exhibiting marked daytime hypoxaemia.…”

Slow wave sleep in patients with respiratory failure

“…To our knowledge, this phenomenon has not previously been reported in observational studies, although few clinical studies have reported SWS data in respiratory failure samples. [11][12][13][14] In a study conducted in 1976, the authors reported "greater than expected stage 4 sleep" (>11%) in 4 out of 10 chronic ventilatory failure patients which is "surprising for their age group"(48-66 yrs). 11 The 10 patients had an average awake PCO 2 of 57mmHg which is similar to our patient group (mean PCO 2 58±10.9 mmHg).…”

“…[11][12][13][14] In a study conducted in 1976, the authors reported "greater than expected stage 4 sleep" (>11%) in 4 out of 10 chronic ventilatory failure patients which is "surprising for their age group"(48-66 yrs). 11 The 10 patients had an average awake PCO 2 of 57mmHg which is similar to our patient group (mean PCO 2 58±10.9 mmHg). The authors did not discuss this observation further, possibly due to small sample size.…”

“…10 A few studies of patients with nocturnal respiratory failure have quantified SWS but none have reported this phenomenon. [11][12][13][14] Interestingly, previous animal studies have shown that hypercapnia, acute or chronic, can lead to slowing of EEG in eels 15 , rats 16 , rabbits 17 , and dogs 18 . Extreme hypercapnia can produce an isoelectric EEG in cats 19 and this has also been observed in a single case report in humans.…”