Your patient is admitted to the hospital and is to undergo brain surgery.

The patient is very anxious and scared of the upcoming surgery.

She begins to hyperventilate and becomes very dizzy.

The client loses consciousness and the STAT ABGs reveal pH 7.61, PaCO2 22 mmHg, and HCO3 25 mEq/L. What is the ABG interpretation based on the findings?

Choice A rationale

Metabolic acidosis is characterized by a primary decrease in bicarbonate (HCO3), typically below the normal range of 22-26 mmol/L, leading to a reduction in pH. Partial compensation would involve a compensatory decrease in PaCO2, normally 35-45 mm Hg. The given arterial blood gas values do not align with these characteristics, as the pH is elevated and HCO3 is within normal limits.

Choice B rationale

Respiratory alkalosis is defined by a primary decrease in PaCO2, below the normal range of 35-45 mm Hg, resulting in an elevation of pH above 7.45. Uncompensated respiratory alkalosis means the bicarbonate level (normal range 22-26 mmol/L) remains within normal limits as the kidneys have not yet had time to excrete bicarbonate to compensate. The provided pH of 7.6 and PaCO2 of 31 mm Hg, with HCO3 of 25 mmol/L, perfectly match these criteria.

Choice C rationale

Respiratory acidosis is characterized by a primary increase in PaCO2, above the normal range of 35-45 mm Hg, leading to a decrease in pH below 7.35. Partial compensation would involve a compensatory increase in bicarbonate. The given arterial blood gas values, particularly the elevated pH and decreased PaCO2, directly contradict the definition of respiratory acidosis.

Choice D rationale

Metabolic alkalosis is defined by a primary increase in bicarbonate (HCO3), typically above the normal range of 22-26 mmol/L, leading to an elevation of pH above 7.45. Partial compensation would involve a compensatory increase in PaCO2. The given arterial blood gas values do not show an elevated bicarbonate level that would indicate a primary metabolic issue.

Choice A rationale

A positive sputum culture definitively identifies the pathogenic microorganisms responsible for the infection within the lungs. This microbiological evidence is crucial for confirming the presence of pneumonia and guiding appropriate antibiotic therapy, distinguishing VAP from other pulmonary issues.

Choice B rationale

A new fever indicates a systemic inflammatory response, often triggered by an infection. In the context of a ventilated patient, a new onset of fever, particularly above 38°C (100.4°F), strongly suggests the presence of a new infection, such as ventilator-associated pneumonia.

Choice C rationale

An SpO2 of 98% indicates excellent oxygen saturation. While desirable, it does not rule out VAP, as patients can initially maintain good oxygenation despite developing an infection, especially if the pneumonia is localized or mild in its early stages.

Choice D rationale

A respiratory rate of 14 breaths per minute is within the normal range. A normal respiratory rate does not indicate the presence or absence of VAP, as patients with early or localized pneumonia might not exhibit significant changes in their respiratory patterns initially.

Choice E rationale

New infiltrates on a Chest X-Ray indicate areas of consolidation or fluid accumulation within the lung tissue. These radiological findings are highly suggestive of pneumonia, as the inflammatory process associated with infection leads to alveolar filling and opacities visible on imaging.