Soru

A 31-year-old woman, gravida 1, para 0, at 27 weeks gestation comes to the office for a routine prenatal visit. She mentions feeling "short of breath" over the past two weeks, especially when resting or sitting down. She has no history of asthma or cardiopulmonary disease. She denies chest pain, cough, palpitations, or lightheadedness. Her current medications include a prenatal vitamin and iron supplementation. Vital signs show a blood pressure of $110/68$ mm Hg, a pulse of $84$/min, and respirations of $18$/min. Pulse oximetry is $99\%$ on room air. Physical examination shows a gravid uterus appropriate for gestational age. Lungs are clear to auscultation bilaterally. Cardiac examination shows a normal $S_1$ and $S_2$ with a grade $2/6$ systolic ejection murmur at the left upper sternal border. There is trace bilateral lower extremity edema. The physician reassures the patient that her symptoms are due to normal physiologic adaptations to pregnancy. If an arterial blood gas analysis were performed, which of the following sets of values would most likely be observed?