title: Interest of an objective evaluation of cough during weaning from mechanical ventilation.
abstract: OBJECTIVE
  This study aimed to evaluate an objective measure of cough strength, the peak cough expiratory flow (PCEF), as a predictive criterion of success or failure of extubation.
  
  
  METHODS
  Patients under mechanical ventilation for more than 24 h who successfully passed the spontaneous breathing trial were included in the study. Just before extubation, PCEF was measured with an electronic flowmeter.
  
  
  RESULTS
  A total of 130 patients were included. The median duration of mechanical ventilation before extubation was 8 days (4-17). Fourteen patients (10.8%) failed extubation. The sole factor significantly associated with extubation failure was the measure of PCEF. The patients who did not cough at order had a higher rate of extubation failure than those who did (P = 0.03). The mean PCEF of patients who failed extubation (36.3 +/- 15 l/min) was significantly lower than the one of patients who succeeded (63.6 +/- 32 l/min) (P < 0.001). The optimal cut-off value of PCEF was 35 l/min. Overall, an inability to cough at order or a PCEF < or =35 l/min predicted extubation failure with a sensitivity of 79% and a specificity of 71%. The risk of extubation failure was 24% for the patients who did not cough at order or with a PCEF < or =35 l/min and 3.5% for those with a PCEF >35 l/min [RR = 6.9 (95% CI, 2-24); P = 0.002].
  
  
  CONCLUSIONS
  This study confirmed the interest of measuring the PCEF to predict extubation outcome in patients having successfully passed the spontaneous breathing trial.
authors.affiliation: Intensive Care Unit, Centre Hospitalier Roanne, 28 rue de Charlieu, 42328 Roanne, France. pascal.beuret@ch-roanne.fr
authors.forename: Pascal
authors.initials: P
authors.lastname: Beuret
authors.forename: Christophe
authors.initials: C
authors.lastname: Roux
authors.forename: Annie
authors.initials: A
authors.lastname: Auclair
authors.forename: Karim
authors.initials: K
authors.lastname: Nourdine
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Kaaki
authors.forename: Marie-Jose
authors.initials: MJ
authors.lastname: Carton
mesh_terms: D000368:Aged; D003371:Cough; D005260:Female; D005540:Forced Expiratory Flow Rates / Q000502:physiology; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D015300:Ventilator Weaning / Q000592:standards*