title: [Hypercapnic respiratory failure. Pathophysiology, indications for mechanical ventilation and management].
abstract: BACKGROUND
  Acute hypercapnic respiratory failure is mostly seen in patients with chronic obstructive pulmonary disease (COPD) and obesity hypoventilation syndrome (OHS). Depending on the underlying cause it may be associated with hypoxemic respiratory failure and places high demands on mechanical ventilation.
  
  
  OBJECTIVE
  Presentation of the current knowledge on indications and management of mechanical ventilation in patients with hypercapnic respiratory failure.
  
  
  METHODS
  Review of the literature.
  
  
  RESULTS
  Important by the selection of mechanical ventilation procedures is recognition of the predominant pathophysiological component. In hypercapnic respiratory failure with a pH < 7.35 non-invasive ventilation (NIV) is primarily indicated unless there are contraindications. In patients with severe respiratory acidosis NIV requires a skilled and experienced team and close monitoring in order to perceive a failure of NIV. In acute exacerbation of COPD ventilator settings need a long expiration and short inspiration time to avoid further hyperinflation and an increase in intrinsic positive end-expiratory pressure (PEEP). Ventilation must be adapted to the pathophysiological situation in patients with OHS or overlap syndrome. If severe respiratory acidosis and hypercapnia cannot be managed by mechanical ventilation therapy alone extracorporeal venous CO2 removal may be necessary. Reports on this approach in awake patients are available.
  
  
  CONCLUSIONS
  The use of NIV is the predominant treatment in patients with hypercapnic respiratory failure but close monitoring is necessary in order not to miss the indications for intubation and invasive ventilation. Methods of extracorporeal CO2 removal especially in awake patients need further evaluation.
authors.affiliation: Abteilung für Pneumologie, Schlaf- und Beatmungsmedizin, Lungenklinik Hemer, Theo-Funccius-Str. 1, 58675, Hemer, Deutschland.
authors.forename: U
authors.initials: U
authors.lastname: Kreppein
authors.affiliation: Abteilung für Pneumologie, Schlaf- und Beatmungsmedizin, Lungenklinik Hemer, Theo-Funccius-Str. 1, 58675, Hemer, Deutschland.
authors.forename: P
authors.initials: P
authors.lastname: Litterst
authors.affiliation: Abteilung für Pneumologie, Schlaf- und Beatmungsmedizin, Lungenklinik Hemer, Theo-Funccius-Str. 1, 58675, Hemer, Deutschland. michael.westhoff@lkhemer.de.|Universität Witten/Herdecke, 58448, Witten, Deutschland. michael.westhoff@lkhemer.de.
authors.forename: M
authors.initials: M
authors.lastname: Westhoff
mesh_terms: D000142:Acidosis, Respiratory / Q000503:physiopathology / Q000628:therapy; D002658:Developmental Disabilities / Q000503:physiopathology / Q000628:therapy; D005385:Fingers / Q000002:abnormalities / Q000503:physiopathology; D006801:Humans; D006935:Hypercapnia / Q000503:physiopathology* / Q000628:therapy*; D000860:Hypoxia / Q000503:physiopathology / Q000628:therapy; D008607:Intellectual Disability / Q000503:physiopathology / Q000628:therapy; D008168:Lung / Q000503:physiopathology; D008831:Microcephaly / Q000503:physiopathology / Q000628:therapy; D009123:Muscle Hypotonia / Q000503:physiopathology / Q000628:therapy; D009216:Myopia / Q000503:physiopathology / Q000628:therapy; D063087:Noninvasive Ventilation / Q000379:methods; D009765:Obesity / Q000503:physiopathology / Q000628:therapy; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology / Q000628:therapy; D012121:Respiration, Artificial / Q000379:methods*; D012131:Respiratory Insufficiency / Q000503:physiopathology* / Q000628:therapy*; D012162:Retinal Degeneration
keywords: Acidosis, respiratory; Mechanical ventilation; Noninvasive ventilation; Obesity hypoventilation syndrome; Pulmonary disease, chronic obstructive