Using the formula PVR = (PAP - PAOP)/CO × 80, calculate the pulmonary vascular resistance for a patient with PAP 20 mm Hg, PAOP 12 mm Hg, and CO 4 L/min.

Using the formula PVR = (PAP - PAOP)/CO × 80, calculate the pulmonary vascular resistance for a patient with PAP 20 mm Hg, PAOP 12 mm Hg, and CO 4 L/min.

• A. 40 dynes-sec-cm-5
• B. 80 dynes-sec-cm-5
• C. 160 dynes-sec-cm-5
• D. 200 dynes-sec-cm-5

Answer: (C)

PVR reflects the right ventricle’s afterload and is calculated from the transpulmonary pressure gradient divided by flow, with a conversion factor to convert to dynes·sec·cm^-5. Start by finding the gradient: 20 minus 12 equals 8 mmHg. Then divide by the cardiac output: 8 / 4 = 2 mmHg·min/L. Multiply by 80 to convert to the standard unit: 2 × 80 = 160 dynes·sec·cm^-5. The pulmonary vascular resistance is 160 dynes·sec·cm^-5.

PVR reflects the right ventricle’s afterload and is calculated from the transpulmonary pressure gradient divided by flow, with a conversion factor to convert to dynes·sec·cm^-5. Start by finding the gradient: 20 minus 12 equals 8 mmHg. Then divide by the cardiac output: 8 / 4 = 2 mmHg·min/L. Multiply by 80 to convert to the standard unit: 2 × 80 = 160 dynes·sec·cm^-5. The pulmonary vascular resistance is 160 dynes·sec·cm^-5.