Head rotation of 45° in anaesthetised apnoeic adults significantly increases the efficiency of mask ventilation compared with the neutral head position. Head rotation is an effective alternative to improve mask ventilation if airway obstruction is encountered.

In this study, we observed the effect of head rotation on VTE was greatest in patients with airway obstruction and low VTE during the neutral head position.

We originally defined these two subgroups because these populations are those most in need of some rescue manoeuvres during mask ventilation.

As normal tidal volume is 5 to 7 ml kg−1 during spontaneous breathing at rest, we selected 6 ml kg−1 as the cut-off value for low VTE, although this value may not represent sufficient mask ventilation to the extent that adequate preoxygenation is obtained when difficult tracheal intubation is not suspected.

Read More