title: The effect of targeting scheme on tidal volume delivery during volume control mechanical ventilation.
abstract: BACKGROUND
  Technological advances have increased ventilator mode complexity and risk of operator error.
  
  
  OBJECTIVE
  To compare differences in volume control (VC) ventilation with set-point and dual targeting. Two hypotheses were tested: tidal volume (V(T)) delivery is different  with VC using set-point versus dual targeting during active versus passive breathing; VC with dual targeting delivers V(T) similar to pressure support ventilation (PS) with active breathing.
  
  
  METHODS
  The Ingmar Medical ASL 5000 lung model simulated pulmonary mechanics of an adult  patient with ARDS during active and passive ventilation. Resistance was standardized at 10 cm H(2)O/L/s and compliance at 32 mL/cm H(2)O. Active breathing was simulated by setting the frequency (f) = 26 breaths/min, and adjusting the muscle pressure (P(mus)) to produce  a V(T) of 384 mL. VC was initiated with the Puritan Bennett 840 (set-point targeting) and the Servo-i (dual targeting) at V(T) = 430 mL, mandatory f = 15 breaths/min, and PEEP = 10 cm H(2)O. During PS, cycle threshold was set to 30% and peak inspiratory pressure  adjusted to produce a V(T) similar to that delivered during VC. Expiratory V(T) was collected on 10 consecutive breaths during active and passive breathing with VC and PS. Mean V(T) differences (active vs passive model) were compared using analysis of variance. Statistical  significance was established at P < .05.
  
  
  RESULTS
  The mean ± SD V(T) difference varied with targeting schemes: VC set-point = 37.3 ± 3.5 mL, VC-dual = 77.1 ± 3.3 mL, and PS = 406.1 ± 1.5 mL (P < .001). Auto-triggering occurred during  VC set-point with the active model.
  
  
  CONCLUSIONS
  Dual targeting during VC allows increased V(T), compared to set-point, but not as much as PS.
authors.affiliation: Department of Health Professions, Youngstown State University, Youngstown, Ohio, USA. TVolsko@chmca.org
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Volsko
authors.forename: Justin
authors.initials: J
authors.lastname: Hoffman
authors.forename: Alecia
authors.initials: A
authors.lastname: Conger
authors.forename: Robert L
authors.initials: RL
authors.lastname: Chatburn
mesh_terms: D000328:Adult; D003198:Computer Simulation; D006801:Humans; D011659:Pulmonary Gas Exchange; D012121:Respiration, Artificial / Q000379:methods*; D015656:Respiratory Mechanics / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013990:Tidal Volume / Q000502:physiology*; D014584:User-Computer Interface; D014939:Work of Breathing / Q000502:physiology