title: Impact of Initial Ventilatory Strategy in Hematological Patients With Acute Respiratory Failure: A Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  Acute respiratory failure in hematological patients is related to a high mortality. Noninvasive mechanical ventilation may benefit a subset of these patients, but the overall effect on mortality and the risks derived from its failure are unclear. Our objective was to review the impact of initial ventilatory strategy on mortality and the risks related to noninvasive mechanical ventilation failure in this group of patients.
  
  
  METHODS
  Data sources, including PubMed and conference proceedings, were searched from the year 2000 to January 2015.
  
  
  METHODS
  We selected studies reporting mortality and the need for mechanical ventilation in hematological patients with acute respiratory failure.
  
  
  METHODS
  Two trained reviewers independently conducted study selection, abstracted data, and assessed the risk of bias. Discrepancies between reviewers were resolved through discussion and consensus. The outcomes explored were all-cause mortality after mechanical ventilation and incidence of noninvasive mechanical ventilation failure.
  
  
  RESULTS
  A random-effects model was used in all the analysis. Thirteen studies, involving 2,380 patients, were included. Use of noninvasive mechanical ventilation was related to a better outcome than initial intubation (risk ratio, 0.74; 95% CI, 0.65-0.84). Failure of noninvasive mechanical ventilation did not increase the overall risk of death (risk ratio, 1.02; 95% CI, 0.93-1.13). There were signs of publication bias and substantial heterogeneity among the studies. Compensation of this bias by using the trim-and-fill method showed a significant risk of death after noninvasive mechanical ventilation failure (risk ratio, 1.07; 95% CI, 1.00-1.14). Meta-regression analysis showed that the predicted risk of death for the noninvasive mechanical ventilation group acted as a significant moderator, with a higher risk of death after noninvasive mechanical ventilation failure in those studies reporting lower predicted mortality.
  
  
  CONCLUSIONS
  Noninvasive mechanical ventilation is associated with a lower risk of death in hematological patients with respiratory failure. Noninvasive mechanical ventilation failure may worsen the prognosis, mainly in less severe patients.
authors.affiliation: 1Área de Gestión Clínica de Medicina Intensiva, Hospital Valle del Nalón, Langreo, Spain. 2Departamento de Biología Funcional, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain. 3Servicio de Hematología, Hospital Universitario Central de Asturias, Oviedo, Spain. 4Departamento de Medicina, Universidad de Oviedo, Oviedo, Spain. 5Servicio de Medicina Intensiva, Hospital Universitario Central de Asturias, Oviedo, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Amado-Rodríguez
authors.forename: Teresa
authors.initials: T
authors.lastname: Bernal
authors.forename: Inés
authors.initials: I
authors.lastname: López-Alonso
authors.forename: Jorge
authors.initials: J
authors.lastname: Blázquez-Prieto
authors.forename: Emilio
authors.initials: E
authors.lastname: García-Prieto
authors.forename: Guillermo M
authors.initials: GM
authors.lastname: Albaiceta
mesh_terms: D000208:Acute Disease; D006402:Hematologic Diseases / Q000150:complications* / Q000401:mortality; D006801:Humans; D012121:Respiration, Artificial / Q000379:methods*; D012131:Respiratory Insufficiency / Q000209:etiology / Q000401:mortality / Q000628:therapy*