added nbme12 tag, card helps directly helps answer the Q:
A woman is brought to the emergency department 30 minutes after an episode of syncope at a shopping mall. She says she had shortness of breath and was sweating before she passed out. She currently has panic disorder and gastroesophageal reflux disease. Current medications include sertraline, omeprazole, and an oral contraceptive. On arrival, she is alert and oriented to person, place, and time. Her temperature is 37.4°C (99.3°F), pulse is 110/min, and blood pressure is 90/60 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 90%. Exam shows no abnormalities.
Laboratory studies show:
Hemoglobin 12 g/dL
Leukocyte count 9000/mm
Arterial blood gas:
pH 7.46
Pco 30 mm Hg
Po 62 mm Hg
Which of the following is the most likely explanation for these findings?
Ans: Pulmonary Embolism
Arterial blood gas analysis most typically shows acute respiratory alkalosis, hypoxemia, and an increased A-a gradient caused by ventilationperfusion mismatch