And the risk for EDS is even increased when OSA is associated with obesity.Due to all the consequences and symptoms it generates, OSA in children lead to a significant decrease in the quality of life, the decrease being even higher when obesity is present. The quality of life can however be improved with the treatment of OSA. SBD have also been linked to a higher rate of internalizing disorders such as anxiety and depression. Indeed, depressive symptoms have shown to be higher in children with OSA, especially in males. Once again, the severity of depressive symptoms is positively correlated with the severity of the SBD. It also interacts with obesity as obese children have higher risk to show depressive symptoms and obesity can cause OSA. The link can also go the other way around with the depression inducing obesity (due to overeating) which worsens the OSA. Adenotonsillectomy can decrease the intensity of the depressive symptoms.Other consequences of a disturbed sleep in children with OSA comprise anhedonia increased fatigue and decreased interest in daily activities, which in turn can affect the childs social relationships. In adults
While there are some similarities between adults and children, OSA does not have the same consequences in both populations. Examples of similarities are the snoring – which is the most common complaint in both pediatric OSA and OSA in adults – variability of blood pressure and cardiovascular morbidities.
Hypoventilation in COPD involves multiple mechanisms, including decreased responsiveness to hypoxia and hypercapnia, increased ventilation-perfusion mismatch leading to increased dead space ventilation, and decreased diaphragm function secondary to fatigue and hyperinflation. Chronic respiratory acidosis also may be secondary to obesity hypoventilation syndrome (i.e., Pickwickian syndrome), neuromuscular disorders such as amyotrophic lateral sclerosis, and severe restrictive ventilatory defects as observed in interstitial lung disease and thoracic deformities. Lung diseases that primarily cause abnormality in alveolar gas exchange usually do not cause hypoventilation but tend to cause stimulation of ventilation and hypocapnia secondary to hypoxia. Hypercapnia only occurs if severe disease or respiratory muscle fatigue occurs. Physiological response
Mechanism
Metabolism rapidly generates a large quantity of volatile acid (H2CO3) and nonvolatile acid. The metabolism of fats and carbohydrates leads to the formation of a large amount of CO2. The CO2 combines with H2O to form carbonic acid (H2CO3). The lungs normally excrete the volatile fraction through ventilation, and acid accumulation does not occur. A significant alteration in ventilation that affects elimination of CO2 can cause a respiratory acid-base disorder. The PaCO2 is maintained within a range of 35–45 mm Hg in normal states. Alveolar ventilation is under the control of the respiratory center, which is located in the pons and the medulla. Ventilation is influenced and regulated by chemoreceptors for PaCO2, PaO2, and pH located in the brainstem, and in the aortic and carotid bodies as well as by neural impulses from lung stretch receptors and impulses from the cerebral cortex. Failure of ventilation quickly increases the PaCO2.