Emergency medical personnel transport an elderly resident from an assisted living facility to the acute medical unit. The staff reported a three-day decline in functional status, noting increased thirst, frequent urination, and an escalating, non-productive cough. Medical records indicate long-standing insulin-requiring diabetes mellitus and severe chronic obstructive pulmonary disease.
Upon arrival, the patient is somnolent but appropriately follows simple commands. Vital signs reveal a temperature of 37.0°C (98.6°F), heart rate of 118/min, blood pressure of 105/62 mm Hg, and a respiratory rate of 28/min with shallow, labored breathing. Oxygen saturation is 90% on ambient air. Physical examination demonstrates poor skin turgor, prominent use of accessory muscles of respiration, and diffuse expiratory wheezing with a prolonged expiratory phase. Jugular venous pressure is estimated at 4 cm H2O.
Initial laboratory studies are obtained:
| Test | Result |
|---|---|
| Serum sodium | 134 mEq/L |
| Serum potassium | 4.9 mEq/L |
| Serum chloride | 96 mEq/L |
| Serum bicarbonate | 12 mEq/L |
| Blood urea nitrogen | 42 mg/dL |
| Serum creatinine | 1.8 mg/dL |
| Serum glucose | 540 mg/dL |
Arterial blood gas analysis on ambient air:
| Test | Result |
|---|---|
| pH | 7.15 |
| PaCO2 | 38 mm Hg |
| PaO2 | 65 mm Hg |
In addition to intravenous fluid resuscitation and a continuous regular insulin infusion, which of the following is the most appropriate next step in the management of this patient?
- Initiation of noninvasive positive pressure ventilationAnswer
- BAdministration of intravenous sodium bicarbonate
- CIntravenous administration of furosemide
- DEmpiric therapy with intravenous piperacillin-tazobactam
- EMeasurement of serum thyroid-stimulating hormone and free thyroxine