YOUNG

Clinical Question

In mechanically ventilated adults patients with suspected hypoxic ischaemic encephalopathy does conservative oxygen therapy when compared with usual oxygen therapy decrease the risk of dying or surviving with an unfavourable neurological outcome at 180 days?

Critical Appraisal

Key findings

Primary outcome: Death or survival with an unfavourable neurological outcome at 180 days –
no significant difference Unfavourable neurological outcome = Extended Glasgow Outcome Scale (GOS-E)
category 1-4

Critique

Conservative oxygen therapy was not associated with a statistically
significant reduction in death or unfavourable neurological outcome at day
180 compared with usual oxygen therapy. Statistically significant increases in number of ventilator and vasopressor
free days in patients in conservative oxygen therapy group. However it is
important to recognise that ventilator/vasopressor free days are also a
reflection of mortality and the fact that the date is not normally
distributed. All deaths had zero ventilator/vasopressor free days and
therefore if the mortality if over 50%, the median number of
ventilator/vasopressor free days must be 0. If mortality is less than 50%,
the median number of free days can be much higher. Therefore the magnitude
of difference demonstrated (21.1 vs 0) is less dramatic than it initially
appears

Outcome Results

Not recorded