A nurse is interpreting a client's ECG strip. Which of the following components of the ECG should the nurse examine to determine the time it takes for ventricular depolarization and repolarization?

D. A pulmonary artery catheter is used to monitor hemodynamic status. It provides valuable information about cardiac function, preload, afterload, and cardiac output. By measuring parameters such as pulmonary artery pressure, pulmonary artery wedge pressure, and central venous pressure, a pulmonary artery catheter helps assess the effectiveness of cardiac function and guide management in critically ill patients, especially those with conditions such as heart failure, shock, or pulmonary hypertension.

A. A pulmonary artery catheter, also known as a Swan-Ganz catheter, is not used to monitor intracranial pressure. Instead, it is primarily used to assess hemodynamic status and cardiac function by measuring parameters such as pulmonary artery pressure, pulmonary artery wedge pressure, central venous pressure, and cardiac output.

B. A pulmonary artery catheter is not used to directly monitor renal function. While changes in hemodynamic status can impact renal perfusion and function, the primary purpose of a pulmonary artery catheter is to assess cardiac function and hemodynamics, rather than renal function.

C. A pulmonary artery catheter is not used to monitor spinal cord perfusion. Although alterations in hemodynamic status can affect spinal cord perfusion indirectly, the main purpose of a pulmonary artery catheter is to evaluate cardiac function and hemodynamics.

A. The insertion of a pulmonary artery catheter can help in assessing hemodynamic parameters and distinguishing between these two conditions. It provides direct measurement of pulmonary artery pressures, which can be elevated in the case of heart failure.

B. A ventilation-perfusion (V/Q) scan is used to evaluate ventilation and perfusion in the lungs. While it can help identify areas of ventilation-perfusion mismatch, it may not be the most appropriate initial test for distinguishing between ARDS and pulmonary edema.

C. Drawing blood for arterial blood gases is also a critical step as it helps in assessing the severity of hypoxemia and respiratory failure.

D. A chest x-ray can show the presence of bilateral opacities, which are indicative of ARDS when cardiac failure or fluid overload is not the primary cause. However, transthoracic echocardiography (TTE) is often performed to seek evidence of cardiac dysfunction when cardiogenic pulmonary edema cannot be excluded by clinical evaluation, laboratory findings, or imaging.