A Simple Cardiovascular Model for the Study of Hemorrhagic Shock

Table 1

Model variables.

Variable	Units	Meaning
	mmHg	Arterial pressure
	#	Sympathetic nervous activity
	#	Stimulating output from baroreflex central processing
	/min	Heart rate in beats per minute
		Total peripheral/systemic vascular hydraulic resistance
	mmHg	Preload recruitable stroke work
	L	Venous unstressed volume at which the pressure induced by wall tension is 0 mmHg
	mmHg	Central venous pressure
	L/min	Arterio-venous capillary blood flow
	min	Duration of diastole
	L/min	Veno-arterial flow (cardiac output)
	L	Arterial volume
	L	Current estimate of end-systolic ventricular volume
	L	Current estimate of end-diastolic ventricular volume
	mmHg	Intraventricular pressure at the end of diastole
	mmHg	Intraventricular pressure at the end of systole
	L	End-systolic ventricular volume
	L	End-diastolic ventricular volume
	L/min	External blood withdrawal from the venous compartment
	L/min	Transcapillary refilling rate
	L	Venous volume