On admission, patients presented with a paO 2 /FiO 2 ratio of 58 to 79 (Murray score > 3.0; Table 1 ). After institution of SHFJV, oxygenation improved in all patients within 24 h (paO 2 /FiO 2 ratio 105-306) with a PEEP of 8 to 15 mbar, P peak < 30 mbar, and P mean 15-18 mbar. Therefore, the institution of SHFJV allowed improved oxygenation with adequate DO 2 and a simultaneous reduction of lung injury, inducing high peak and mean pressures at the same time. Spontaneous breathing was set during 8 h after admission. Three patients required jet ventilation for up to 72 h. One patient required prolonged jet ventilation due to concomitant mycoplasma pneumonia, and the other due to persistent H1N1 pneumonia.