The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts


Carl Haas1, Jackie Acree1, Tim Hess1, Dee Wild1, Paul Loik1

Background: Ventilator settings can influence patient outcome. ARDSNet reported that a VT of 6 mL/kg of predicted body weight (PBW) with a Pplat ≤30 cmH2O improved survival in ALI/ARDS patients. Gajic reported VT>12 mL/kg increased likelihood of developing ALI and that females were ventilated with VT's larger than males. In 2002 a table was laminated on our ventilator flow-boards to assist calculating PBW and in June 2007 therapists began documenting VT in mL/kg PBW once per shift.

Study Objectives: To determine whether charting VT in mL/kg PBW impacted the size of delivered VT and the pattern of delivery by gender. Study Design: A retrospective review of a departmental database for 6 quarters prior to and 3 quarters following policy change. Data included patient gender, height, and ventilator settings. PBW was calculated from ARDSNet formula and used to compute VT in mL/kg PBW. Data from the first full day of MV was analyzed.

Results: During the pre-period, a mean VT of 8.9 mL/kg PBW was used vs 8.1 in the post-period. Females were ventilated with a 13.9% (range 11-26%) larger VT than males in the pre-period vs 8.5% (range 8-10%) in the post-period.

Conclusion: Awareness of VT size in mL/kg PBW was associated with in a reduction in VT for both genders and the gap between VT sizes between genders was narrowed. Whether this translates to reduced ALI rate is unknown.