Type II Respiratory failure is characterised by (Davidson)

(Low PaO2/High PaCO2) (1684 -H17th)Respiratory failure - PaO2 <8.0 kPa (60mmHg) and PaCO2 > 6.5 kPa (50 mmHg)Type 1 - PaO2 low, PaCO2 normal or lowType II - PaCO2 raised, PaO2 low - Ventilatory failure* Most important - cause in chronic type II respiratory failure is - chronic bronchitis