单项选择题

A.PaO2<60mmHg或PaCO2>50mmHg
B.血清Na+>155mmol/L或<135mmol/L
C.血清K+<3.0mmol/L或HCO-3<20mmol/L
D.BUN>17.85mmol/L或>50mg/dl
E.Scr>265.2μmol/L或>3mg/dl(正常为45~120μmol/L或0.5~1.4mg/dl)