Calculate the P/F ratio using the following:

P-Pa02 82

F-F102 60%

The P/F ratio is used to assess the degree of hypoxemia in patients, particularly those with acute respiratory distress syndrome (ARDS). A P/F ratio of less than 300 suggests mild ARDS, less than 200 suggests moderate ARDS, and less than 100 indicates severe ARDS.

Given:

PaO₂ (Partial pressure of oxygen in arterial blood) = 82 mm Hg

FiO₂ (Fraction of inspired oxygen) = 60% = 0.60 (in decimal form)

A. ST segment elevation: ST segment elevation is a classic sign of myocardial injury, indicating that a portion of the heart muscle is not receiving enough oxygen and is actively injured.

B. Q wave: A Q wave typically appears later, representing a previous myocardial infarction (necrosis), not acute injury.

C. Inverted T wave: This indicates myocardial ischemia, which is a precursor to injury but not indicative of injury itself.

D. ST segment depression: This is typically associated with ischemia or subendocardial infarction, not full-thickness myocardial injury.

A. An increase in O2 saturation to greater than 90%: An increase in oxygen saturation is typically a positive sign and does not indicate worsening heart failure.

B. The onset of atrial fibrillation: The development of atrial fibrillation (AFib) in a patient with heart failure is a sign of worsening heart failure, as it indicates increased atrial pressure and the potential for further hemodynamic compromise.

C. Louder S1 and S2 heart sounds: Louder heart sounds do not specifically indicate worsening heart failure. They may vary based on other factors such as body habitus or the position of the patient.

D. A decrease in heart rate to 66 bpm: A heart rate of 66 bpm is within the normal range and does not suggest worsening heart failure.