title: Assisted breathing is better in acute respiratory failure.
abstract: OBJECTIVE
  Mechanical ventilation is usually provided in acute lung injury to ensure alveolar ventilation and reduce the patients' work of breathing without further damaging the lungs by the treatment itself. Although partial ventilatory support modalities were initially developed for weaning from mechanical ventilation, they are increasingly used as primary modes of ventilation, even in patients in the acute phase of pulmonary dysfunction. The aim of this paper is to review the role of spontaneous breathing ventilatory modalities with respect to their physiologic or clinical evidence.
  
  
  RESULTS
  By allowing patients with acute lung injury to breathe spontaneously, one can expect improvement in gas exchange and in systemic blood flow, on the basis of both experimental and clinical trials. In addition, by increasing end-expiratory lung volume, as will occur when airway pressure release ventilation is used, recruitment of collapsed or consolidated lung is likely to occur, especially in juxtadiaphragmatic lung regions. Until recently, traditional approaches to mechanical ventilatory support of patients with acute lung injury have called for adaptation of the patient to the mechanical ventilator using heavy sedation and administration of neuromuscular blocking agents. Recent investigations have questioned the utility of sedation, muscle paralysis, and mechanical control of ventilation. Further, evidence exists that lowering sedation levels will decrease the duration of mechanical ventilatory support, the length of stay in the intensive care unit, and the overall costs of hospitalization.
  
  
  CONCLUSIONS
  On the basis of currently available data, the authors suggest the use of techniques of mechanical ventilatory support that maintain, rather than suppress, spontaneous ventilatory effort, especially in patients with severe pulmonary dysfunction.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Germany. putensen@uni-bonn.de
authors.forename: Christian
authors.initials: C
authors.lastname: Putensen
authors.forename: Rudolf
authors.initials: R
authors.lastname: Hering
authors.forename: Thomas
authors.initials: T
authors.lastname: Muders
authors.forename: Hermann
authors.initials: H
authors.lastname: Wrigge
mesh_terms: D000698:Analgesia / Q000379:methods; D016292:Procedural Sedation / Q000379:methods; D006801:Humans; D011659:Pulmonary Gas Exchange; D012074:Remission Induction / Q000379:methods; D012121:Respiration, Artificial / Q000379:methods*; D012128:Respiratory Distress Syndrome / Q000503:physiopathology* / Q000628:therapy*; D013990:Tidal Volume