Hemodynamics Flashcards
Hemodynamic monitoring
The measurement of pressure, flow, and oxygenation within the cardiovascular system
CVP
term only
Central venous pressure
CVP = RAP
PAWP
Term only
Pulmonary artery wedge pressure
Cardiac output (CO)
The volume of blood in liters pumped by the heart in 1 minute.
Cardiac index
The measurement of the CO adjusted for body surface area (BSA)
Stroke volume (SV)
The volume ejected with each heartbeat
Stroke volume index
The measurement of SV adjusted for BSA
SV
Term only
Stroke volume
SVR
Systemic vascular resistance
- resistance of the systemic vascular bed
- opposition encountered by the left ventricle
PVR
Pulmonary vascular resistance
- resistance of the pulmonary vascular bed
- opposition encountered by the right ventricle
Preload
The volume within the ventricle at the end of diastole
Left ventricular end diastolic pressure (LVEDP)
Left ventricular preload
- Not measured directly; measured in pulmonary artery (PAWP)
PAWP
Pulmonary artery wedge pressure
- measurement of pulmonary capillary pressure
- reflects left ventricular end-diastolic pressure under normal conditions
- Norm: 6-12 mmHg
Contractility
Describes the strength of contractions of the heart
- said to increase when preload is unchanged yet the heart contracts more forcefully
Drugs that increase/improve contractility (+ inotropes)
Epinephrine; norepinephrine [Levophed] Isoproterenol (Isuprel) Dopamine (Intropin) Dobutamine (Dobutrex) Digitalis-like drugs Calcium Milrinone
Drugs that reduce contractility (negative inotropes)
Alcohol Calcium channel blockers Beta-adrenergic blockers Anesthetics, sedatives, barbiturates Some chemo agents
Impedance cardiography (ICG)
A continuous or intermittent, noninvasive method of obtaining CO and assessing thoracic fluid status.
Ejection fraction
Amount of blood pumped out of heart compared to how much is remaining
Normal CO value range
4-8 L/min
HR norm range
60-100 beats/min
Stroke volume (SV) normal range
60-150 mL/beat
PAWP normal range
6-12 mm Hg
CVP/RAP normal range
2-8 mmHg
SVR = ?
[(MAP - RAP) / CO] x 80
Norm CVR: 800-1200 dynes/sec/cm-5
SVR norm range
800-1200 dynes/sec/cm-5
CO = ?
SV x HR
Norm CO: 4-8 L/min
ml/min) = (beats/min) x (ml/beat