Abstract
Objective: To investigate the effect of continuous axial rotation (CAR) treatment on the degree of pulmonary oedema (extravascular lung water [EVLW]) and arterial oxygenation in mechanically ventilated patients with acute lung injury (ALI). Design: Prospective investigation in a 12-bed intensive care unit (ICU) of a university hospital. Patients: Sixteen patients with ALI requiring mechanical ventilation. Methods: Random allocation into two groups. In the CAR group (n =8), patients were treated in a kinetic bed for a period of 72 h. In the control group (n =8), patients were treated in a 'conventional' bed. Intrathoracic blood volume (ITBV) and EVLW were assessed by the thermal dye dilution method at baseline (T0) and at 12, 24, 48, and 72 h after baseline. Additionally, arterial oxygenation, serum albumin levels and colloid osmotic pressure values in the serum were measured. Results: After 48 h of treatment, mean EVLW was significantly lower in the CAR group (6.3 ± 1.6 ml/kg [standard deviation, SD]), compared with the control group (11.2 ± 4.9 ml/kg) (p<0.05). In the control group, EVLW tended to increase during the study period. Arterial oxygenation (PaO2/FIO2-ratio) improved continuously during axial rotation therapy and was significantly higher after 24 h of treatment compared with the control group (32 ± 7.5 kPa vs. 21.2 ± 6.6 kPa, p<0.05, respectively). Serum albumin levels, ITBV, and colloid-osmotic pressures in the serum did not show any difference between the two groups during the experimental protocol. Conclusions: Continuous axial rotation caused a reduction of EVLW in patients with ALI. This may be due to continuous changes in intrathoracic pressures during kinetic therapy.