Use of lower tidal volumes (VT) is recommended for patients suffering from ALI/ARDS. We previously reported on a simple ’intervention’ aiming at lowering VT in our institution (goal: VT 6-8 ml/kg): this intervention existed of feedback and education on the use of lower VT, during which special attention was paid to the importance of closely adjusting VT to predicted body weight (PBW) in stead of actual bodyweight (Wolthuis, Intensive Care Med 2005).
To determine the longstanding effects of the above-mentioned intervention, we (a) compared data on VT-settings of mechanically ventilated patients before feedback and education (June 2003, N = 30) with VT-settings 15 months later (September 2004, N = 103); in addition, we (b) collected data on VT-settings of patients recruited in two consecutive randomized controlled ALI/ARDS- trials: the first trial was performed in 10-month period before the intervention (March 2002 –December 2002, N = 12), the second was performed in a 10-month period after the intervention (July 2003 –May 2004, N = 8). Statistical analysis: Mann-Whitney U test. P-value < 0.05 was considered to represent a significant difference.
(a) Before intervention, VT was 9.6 ± 1.8 ml/kg PBW; VT declined shortly after the intervention (8.0 ± 1.8 ml/kg PBW), and remained low (7.8 ± 1.3 ml/kg PBW) 15 months after the intervention. (b) VT in the second randomized controlled trial was significantly lower as compared with VT in the first study on ALI/ARDS-patients: while in the majority of patients in the first study VT was > 10 ml/kg at all times, in the second study almost all VT were between 6 and 8 ml/kg.
Feedback and education caused a sustained decline in VT in mechanically ventilated patients in our institution.
These results possibly underscore the importance of the use of PBW, instead of actual bodyweight, to adjust VT.
Marcus Schultz, None.