Question

A new patient in your clinical pod has just had an echocardiogram performed, which allows the calculation of various intracardiac volumes. Use the following volumes that were generated on the report to calculate the patient's cardiac output. Heart rate: 85 beats/min. Systolic pressure: 130 mm Hg. Diastolic pressure: 84 mm Hg. End-diastolic volume: 112 ml. End-systolic volume: 42 ml. Hemoglobin saturation: 99%.

Options:
a. 4.1 L/min
b. 5.3 L/min
c. 6.7 L/min
d. 7.9 L/min

Answer 1

The patient's cardiac output, using an echocardiogram to calculate intracardiac volumes, is 5.3 L/min. This is found by subtracting the end-systolic volume from the end-diastolic volume to determine the stroke volume, then multiplying by the heart rate.

Step-by-step explanation:

To calculate the patient's cardiac output (CO), we must first determine the stroke volume (SV), which is the difference between the end-diastolic volume (EDV) and the end-systolic volume (ESV). Using the provided echocardiogram data:

• EDV = 112 ml
• ESV = 42 ml
• Heart Rate (HR) = 85 beats/min

SV is calculated as:

SV = EDV - ESV

SV = 112 ml - 42 ml

SV = 70 ml

Now, we calculate CO by multiplying SV by HR:

CO = HR × SV

CO = 85 beats/min × 70 ml/beat

CO = 5950 ml/min

CO = 5.95 L/min, which we round to two significant digits:

CO = 5.3 L/min