Big breathing: the complex interaction of obesity, hypoventilation, weight loss, and respiratory function

Abstract

Obesity places a significant load on the respiratory system, affecting lung volumes, respiratory muscle function, work of breathing, and ventilatory control. Despite this, most morbidly obese individuals maintain eucapnia. However, a subgroup of morbidly obese individuals will develop chronic daytime hypercapnia, described as the obesity hypoventilation syndrome (OHS). While obesity is obviously a crucial component of this syndrome, the relationship between excess fat accumulation and the development of awake hypercapnia is complex and extends beyond simply impairments of pulmonary mechanics and lung volumes as a consequence of obesity. Various compensatory mechanisms operate to maintain eucapnia even in the presence of extreme obesity. However, if compensation is impaired, hypoventilation will ensue. While obesity alone does not account for the development of hypoventilation, weight loss will produce significant improvements in lung function and awake gas exchange. Such improvements have the potential to substantially reduce morbidity and mortality in these individuals. Nevertheless, many individuals remain overweight despite substantial weight loss, with persistence of upper airway obstruction. Attention to this residual abnormality is important given the high incidence of cardiovascular abnormalities, including pulmonary hypertension, in individuals with OHS.

Tele-monitoring of ventilator-dependent patients: a European Respiratory Society Statement

“…The potential of tele-monitoring in hypoventilation syndrome has been less studied and no clear recommendations exist in clinical protocols [39,87,[91][92][93][94][95][96] or procedures [91,97]. Indeed, ICT seems to have a great potential in this field.…”

Efectos de un programa de ejercicio físico estructurado sobre los niveles de condición física y el estado nutricional de obesos mórbidos y obesos con comorbilidades

“…Si bien la cirugía bariátrica parece ser una intervención clínicamente eficaz y rentable para personas con obesidad severa (24), la disminución de peso antes de esta se asocia con una reducción importante del riesgo de complicaciones postoperatorias (25). Reducir el peso corporal disminuye los factores de riesgo cardiovascular (26) y la sintomatología depresiva (27), además de producir mejoras en la función pulmonar (28).…”

The Necessity of Preoperative Pulmonary Function Screening in Patients Scheduled for Bariatric Surgery

“…Secondly, do we need to screen obese patients for the presence of Obstructive Sleep Apnoea Syndrome (OSAS)? [5,6] Because OSAS occurs frequently untreated and might lead to postoperative complications [7][8][9][10].…”