Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial

Table 2 Intraoperative ventilator settings for the PROVAR trial

	Conventional ventilation	Variable ventilation
F _I O ₂	0.35	0.35
PEEP	5 cmH₂O	5 cmH₂O
V _T	8 ml/kg	Mean value of 8 ml/kg, breath by breath variability with a CV V_T of 30%
RR	Adjusted according normocapnia (4.6-6.0 kPa)	Adjusted according normocapnia (4.6 to 6.0 kPa)
I:E	1:1	1:1
Flow	30 L/min, adjusted in case of flow limitation	30 L/min, adjusted in case of flow limitation
P _max	40 cmH₂O	40 cmH₂O

F_IO_2, fraction of inspired oxygen; PEEP, positive end-expiratory pressure; V_T, tidal volume; RR, respiratory rate; I:E, ratio of inspiratory to expiratory time; Flow, air flow; P_max, maximum of inspiratory pressure; CV V_T, coefficient of variation of tidal volume.

ISSN: 1745-6215