Mechanical ventilation is indicated for which of the following ABG results?

a. pH 7.56; PaCO2 27; HCO3 23; PaO2 63
b. pH 7.23; PaCO2 63; HCO3 26; PaO2 52
c. pH 7.36; PaCO2 79; HCO3 43; PaO2 61
d. pH 7.52; PaCO2 51; HCO3 40; PaO2 46

B
When an increased PaCO2 is accompanied by acidemia (decreased pH), acute ventilatory failure, or respiratory acidosis, is said to exist. Clinically, this is a medical emergency that may require mechanical ventilation.