title: In COPD patients on prolonged mechanical ventilation heart rate variability during the T-piece trial is better after pressure support plus PEEP: a pilot physiological study.
abstract: OBJECTIVE
  To evaluate heart rate variability (HRV), hemodynamics, mechanics, dyspnea and blood gases following different mechanical ventilation (MV) settings.
  
  
  BACKGROUND
  No study has evaluated physiological changes during T-piece trials following different MV settings.
  
  
  METHODS
  In 8 COPD patients on prolonged MV we applied in random order two MV settings: i) pressure support (PS) 20 cm H2O + positive end-expiratory pressure (PEEP) 0 cm H2O (setting-1) and ii) PS 15 cm H2O + PEEP 5 cm H2O (setting-2), each followed by a 30 min T-piece trial.
  
  
  RESULTS
  Setting-1 induced greater minute ventilation, tidal volume/inspiratory time and lower pulmonary artery occlusion pressure; setting-2 reduced intrinsic PEEP. Mechanics and hemodynamics data did not differ, but all HRV time domain indices were reduced only after setting-1, suggesting a decreased parasympathetic and increased sympathetic cardiac modulation.
  
  
  CONCLUSIONS
  The T-piece trial following setting-2 seems less stressful on neural control of HRV. Future studies on T-piece trials should consider the residual effect of the MV setting.
authors.affiliation: Respiratory Rehabilitation Division, Salvatore Maugeri Foundation IRCCS, Lumezzane, (BS), Italy. Electronic address: michele.vitacca@fsm.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Vitacca
authors.affiliation: Telemedicine Service, Salvatore Maugeri Foundation IRCCS, Lumezzane, (BS), Italy.
authors.forename: Simonetta
authors.initials: S
authors.lastname: Scalvini
authors.affiliation: Cardiac Rehabilitation Department, IRCCS San Raffaele Pisana, Roma, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Volterrani
authors.affiliation: University of Modena-Reggio Emilia, DU of Medical and Surgical Sciences, (MO), Italy; Ospedale Villa Pineta, Rehabilitation Unit, Pavullo n/F, (MO), Italy.
authors.forename: Enrico Maria
authors.initials: EM
authors.lastname: Clini
authors.affiliation: Respiratory Rehabilitation Division, Salvatore Maugeri Foundation IRCCS, Lumezzane, (BS), Italy.
authors.forename: Mara
authors.initials: M
authors.lastname: Paneroni
authors.affiliation: Cardiac Rehabilitation Division, Salvatore Maugeri Foundation IRCCS, Lumezzane, (BS), Italy.
authors.forename: Amerigo
authors.initials: A
authors.lastname: Giordano
authors.affiliation: Pulmonary Rehabilitation and Weaning Unit, Auxilium Vitae, Volterra, (PI), Italy.
authors.forename: Nicolino
authors.initials: N
authors.lastname: Ambrosino
mesh_terms: D000368:Aged; D018592:Cross-Over Studies; D006339:Heart Rate / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011175:Positive-Pressure Respiration / Q000379:methods*; D011312:Pressure; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000628:therapy*; D012121:Respiration, Artificial / Q000379:methods*; D013990:Tidal Volume
keywords: COPD; Difficult weaning; Mechanical ventilation; Spontaneous breathing trial; Tracheostomy