Determine frequency by clinical condition - use your judgement
In general, it takes 30 mins for blood gases to stabilise following a ventilator change
PCO2 can fall rapidly changing from conventional to HFOV
Use oxygen sats and ETCO2 (need plateau in trace to be reliable) to reduce gas sampling frequency
Too much O2 is harmful - reduce FiO2 to maintain pO2 in the mid-teens.
Low pCO2 causes poor cerebral perfusion: if pCO2 < 4.5kPa: immediately change ventilation and repeat blood gas in 30 mins.
There is no need to order daily routine CXR on all patients. Use your clinical judgement.
In general if a patient has stable or decreasing ventilation, there is no need for a daily CXR
Consider CXR daily if on HFOV, checking to ensure the degree of inflation is appropriate.