Q2: Explain the effect of supplemental oxygen on the arterial blood gas result (point A to point B; see fig 1 on p 242) Increasing the inspired oxygen has improved the oxygenation; however, the carbon dioxide and bicarbonate have risen further. This is because compensation for metabolic alkalosis involves hypoventilation, leading to respiratory acidosis. The degree of hypoventilation is limited...

Background: There is a significant burden of sleep disordered breathing (SDB) in patients living with severe and complex obesity undergoing pre-bariatric surgery assessment. This longitudinal observational study evaluated the hypoventilation syndrome (OHS) this cohort therapeutic compliance commenced on positive airway pressure treatment.

We report on a 70-year-old man with severe respiratory failure caused by obesity hypoventilation syndrome due to abdominal adiposis. Obesity hypoventilation syndrome is a severe condition that is diagnosed when all of the following criteria are satisfied: body-mass index >30 kg/m(2); apnea hypopnea index >30; PaCO2 >45 mm Hg (in the daytime); and marked daytime somnolence. Abdominoplasty, which...

Obesity hypoventilation syndrome (OHS) is defined as obesity (body mass index, >30 kg/m2) with daytime hypoventilation (PCO2, >45 mmHg) that is not secondary to cardiopulmonary or neurologic disease. Around 80–90% of the patients with OHS have obstructive sleep apnea and severe arterial oxygen desaturation. Obstructive sleep apnea has been found to be associated with a variety of eye diseases, ...

A 3-year-old boy presented with brainstem astrocytoma and central alveolar hypoventilation syndrome. Contrast MRI of the brain showed that the tumor involved the cerebellum, with compression of brainstem, and resolved after surgical resection. Polysomnography performed before and after total tumor resection showed significant improvement in nocturnal respiratory rate, respiratory disturbance in...

OHS is also known as Pickwickian syndrome, named for a character—a “fat boy” who is constantly falling asleep—in The Posthumous Papers of the Pickwick Club by Charles Dickens. Salient features of OHS are: Obesity (body mass index ≥ 30 kg/m • 2) Sleep-disordered breathing (most patients with • OHS are morbidly obese and have severe obstructive sleep apnea1) Chronic daytime alveolar hypoventilati...

Diagnostic or therapeutic flexible bronchoscopy is often necessary in severely ill patients. These patients often have comorbidities that increase the risk of bronchoscopy-related complications. Noninvasive ventilation might decrease the risk of these complications in patients with severe refractory hypoxemia, postoperative respiratory distress, or severe emphysema, and in pediatric patients. N...

We describe a case of the juvenile form of Pompe's disease that presented as primary alveolar hypoventilation due to respiratory muscle involvement. This 17-year-old girl had been asymptomatic until this admission, although she had a delayed puberty. Arterial blood gas analysis, pulmonary function test as well as physical findings were compatible with chronic alveolar hypoventilation syndrome. ...

Central Congenital Hypoventilation Syndrome (CCHS) is a rare diagnosis that presents with various forms of autonomic dysfunction. The disease is characterized by reduced chemoreflexes and severe hypoventilation during sleep. Several case reports have noted that patients with CCHS have been found to suffer from hypoglycemic episodes, which frequently present as a seizure. In this report, we will...

Nocturnal hypoventilation is a common feature of disorders affecting the function of the diaphragm or central respiratory drive mechanisms. The ensuing change in gas exchange is initially confined to rapid eye movement (REM) sleep, but over time buffering of the raised carbon dioxide produces a secondary depression of respiratory drive that will further reduce ventilation not only during sleep ...