Question

Given the information below please choose the correct answer with an explanation of why you chosed that answer.

Case 2 – New data set: ABP = 90/60 mm Hg, HR 145 Beats/min, cardiac output = 3 l/min, CVP = 12 mm Hg, PAP = 45/30 mm Hg, PCWP = 18 mm Hg, Ejection Fraction = 20%.

Mean arterial pressure (MAP)	70                mmHg
Systemic vascular resistance (SVR)	1547          dynes
Mean pulmonary artery pressure (PA mean)	17          mm Hg
Pulmonary vascular resistance (PVR)	453                  dynes
Stroke volume (SV)	21                      ml

***Regarding Case 2. The cardiac output is most likely lower than normal because:

preload is low

afterload is low

contractility is low

tachycardia is preventing adequate time during diastole to allow adequate filling of the ventricles

Answer 1

Answer: The cardiac output is most likely lower than normal because tachycardia is preventing adequate time during diastole to allow adequate filling of the ventricles.

This is because increase in the heart rate causes more blood flow and hence decrease in heart rate lowers the cardiac output.