A 70 year old lady presents with shortness of breath 3 days after surgery for an abdominal mass.Vital signs:

BP 100/60

HR 90/min

RR 30/min

Her blood tests show:

pH 7.20

pCO2  54 mmHg

HCO3  21 mmol/l

BE  -7

Na  141

K  2.9

Cl  105

Lactate  6.6

Glu  7.6

Describe and interpret the venous gas