title: Physiological effects of meals in difficult-to-wean tracheostomised patients with chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  To evaluate effects of meals in difficult-to-wean tracheostomised patients with chronic obstructive pulmonary diseases during spontaneous breathing or Inspiratory Pressure Support.
  
  
  METHODS
  Prospective, crossover, randomised, and physiological study.
  
  
  METHODS
  Weaning centre.
  
  
  METHODS
  Sixteen COPD undergoing either decreasing levels of pressure support or increasing periods of spontaneous breathing.
  
  
  METHODS
  Each patient underwent monitoring during a 30-min procedure, during and after meals either under pressure support or spontaneous breathing on two consecutive days. Inductance plethysmography was used to monitor respiratory rate and tidal volume. Tidal volume by a flow transducer, arterial oxygen saturation, pulse rate, end-tidal CO2(,) and dyspnoea by a visual analogue scale were also assessed.
  
  
  RESULTS
  ANOVA analysis showed a significant increase under spontaneous breathing for respiratory rate (P<0.001) and for end tidal CO(2) (P<0.03) induced by the meals. Inspiratory pressure support was associated to significantly greater tidal volume (P<0.001), lower respiratory rate (P<0.032), lower respiratory rate/tidal volume (P<0.001), and lower pulse rate (P<0.047) than spontaneous breathing. Under spontaneous breathing but not under pressure support a statistically worsening in meal-induced dispnoea (P<0.001) was found.
  
  
  CONCLUSIONS
  In tracheostomised difficult-to-wean COPD patients: 1) under unassisted breathing, meals may induce an increase in respiratory rate, end-tidal CO(2), and dyspnoea; 2) inspiratory pressure support ventilation prevents dyspnoea from worsening during meals.
authors.affiliation: Pulmonary Unit, Weaning Centre, S. Maugeri Foundation IRCCS, Via Pinidolo 23, 25064 Gussago, Italy. mvitacca@fsm.it
authors.forename: Michele
authors.initials: M
authors.lastname: Vitacca
authors.forename: Giovanna
authors.initials: G
authors.lastname: Callegari
authors.forename: Maria
authors.initials: M
authors.lastname: Sarvà
authors.forename: Luca
authors.initials: L
authors.lastname: Bianchi
authors.forename: Luca
authors.initials: L
authors.lastname: Barbano
authors.forename: Bruno
authors.initials: B
authors.lastname: Balbi
authors.forename: Nicolino
authors.initials: N
authors.lastname: Ambrosino
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D018592:Cross-Over Studies; D004435:Eating / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology* / Q000628:therapy*; D012121:Respiration, Artificial; D014139:Tracheostomy; D015300:Ventilator Weaning