The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts


Carl Haas1, Kimberly Bauser1, Linda Folk1, Susan Henning1, Paul Loik1, Bob McClish1, Michael Bandy1, Sue Hieber1

Background: Ventilator settings can influence patient outcome. ARDSNet demonstrated that a VT of 6 mL/kg of predicted body weight (PBW) with a Pplat ?30 cmH2O improved survival in ALI/ARDS patients. Studies suggest using VTs >10-12 mL/kg PBW may increase the likelihood of developing ALI/ARDS. Study Objectives: To determine: 1) tidal volume in mL/kg PBW, 2) VT vs Pplat relationship, and 3) PEEP levels used over a 4-year period.

Methods: A retrospective review of a departmental database from 2004-2007. Data included patient gender and height, and ventilator settings and airway pressures. PBW was calculated from the ARDSNet formula and used to compute VT in mL/kg PBW. Data from the first full day of MV was analyzed.

Results: Mean VT decreased each year. Mean VT in 2004 for 3 of 6 adult ICU's was >10 mL/kg PBW vs <9 mL/kg for all six ICUs in 2007. Females were ventilated with larger VTs than males by 10-13%. Mean Pplat remained constant. PEEP levels increased slightly each year; 12% of patients used >8 cmH2O in 2004 vs >30% in 2007. The % of patient with VT <10 mL/kg & Pplat <30 increased each year, while those with a VT >12 mL/kg decreased.

Conclusion: VT declined each year. To help ensure clinician awareness of the specific VT delivered, therapists are required to chart VT in mL/kg PBW. Whether these changes impacted development of ALI is unknown.