title: Effects of Leak Compensation on Patient-Ventilator Synchrony During Premature/Neonatal Invasive and Noninvasive Ventilation: A Lung Model Study.
abstract: BACKGROUND
  During both nasal noninvasive ventilation (NIV) and invasive ventilation of neonates, the presence of air leaks causes triggering and cycling asynchrony.
  
  
  METHODS
  Five ICU ventilators (PB840, PB980, Servo-i, V500, and Avea) were compared in available invasive ventilation and NIV ventilator modes (pressure control continuous spontaneous ventilation [PC-CSV] and pressure control continuous mandatory ventilation [PC-CMV]). The V500 and Avea do not provide PC-CSV and PC-CMV in NIV. The Servo-i and Avea were tested with and without their proximal flow sensor. The ASL 5000 lung model (version 3.5) was used to simulate 4 neonatal scenarios (body weight 0.5, 1, 2, and 4 kg). The ASL 5000 was ventilated via endotracheal tube (invasive ventilation) or nasal cannula (NIV) with 4 different leaks.
  
  
  RESULTS
  The Avea (without flow sensor) during invasive ventilation and Servo-i and PB840 during NIV were not triggered by inspiratory efforts of the ASL 5000 at the baseline leak in the 0.5 kg scenario. In invasive ventilation, overall (median) asynchrony index was significantly lower with the PB980 (1%) and V500 (3%) than with the Servo-i (with flow sensor, 50%; without flow sensor, 50%) and Avea (with sensor, 50%; without sensor, 62%) (P < .05 for all comparisons). The PB840 (33%) was significantly different from all ventilators (P < .05). In NIV, the asynchrony index was significantly lower in PB980 (2%) than in the Servo-i (with sensor, 100%; without sensor, 100%) and PB840 (75%) (P < .05 for both). There was no difference in asynchrony index between PC-CSV and PC-CMV in all tested conditions and ventilators.
  
  
  CONCLUSIONS
  The ability of leak compensation to prevent asynchronous breathing varied widely between ventilators and lung mechanics. The PB980 and V500 were the only two ventilators to acclimate to all leak scenarios in invasive ventilation, and PB980 was the only ventilator to acclimate to all leak scenarios in NIV.
authors.affiliation: Department of Respiratory Care, Massachusetts General Hospital, Boston, Massachusetts.|Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Taiga
authors.initials: T
authors.lastname: Itagaki
authors.affiliation: Department of Respiratory Care, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Chenelle
authors.affiliation: Department of Respiratory Care, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Desmond J
authors.initials: DJ
authors.lastname: Bennett
authors.affiliation: Department of Respiratory Care, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Fisher
authors.affiliation: Department of Respiratory Care, Massachusetts General Hospital, Boston, Massachusetts. rkacmarek@mgh.harvard.edu.|Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Kacmarek
mesh_terms: D003198:Computer Simulation; D003422:Critical Care; D004867:Equipment Design; D004868:Equipment Failure; D019544:Equipment Failure Analysis; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000502:physiology*; D008954:Models, Biological; D063087:Noninvasive Ventilation / Q000295:instrumentation*; D012121:Respiration, Artificial / Q000295:instrumentation*; D012122:Ventilators, Mechanical / Q000592:standards
keywords: acute care ventilator; invasive ventilation; leak compensation; neonatal ventilation; noninvasive ventilation