70: Central Venous/Right Atrial Pressure Monitoring

Published on 06/03/2015 by admin

Filed under Critical Care Medicine

Last modified 06/03/2015

Print this page

rate 1 star rate 2 star rate 3 star rate 4 star rate 5 star
Your rating: none, Average: 2 (1 votes)

This article have been viewed 1391 times

PROCEDURE 70

Central Venous/Right Atrial Pressure Monitoring

PREREQUISITE NURSING KNOWLEDGE

• Knowledge of the normal anatomy and physiology of the cardiovascular system is needed.

• Knowledge of the principles of aseptic technique and infection control is necessary.

• Knowledge is needed of the principles of hemodynamic monitoring.

• The central venous pressure (CVP)/right atrial pressure (RAP) represents right-sided heart preload or the volume of blood found in the right ventricle at the end of diastole.

• CVP/RAP influences and is influenced by venous return and cardiac function. Although the CVP/RAP is used as a measure of changes in the right ventricle, the relationship is not linear. Because the right ventricle has the ability to expand and alter its compliance, changes in volume can occur with little change in pressure.

• The CVP/RAP normally ranges from 2 to 8 mm Hg in the adult.

• The central venous catheter is inserted in a central vein with the tip of the catheter placed in the proximal superior vena cava.

• Knowledge is needed of the setup, leveling, and zeroing of the hemodynamic monitoring system (see Procedure 76).

• Understanding of a, c, and v waves is necessary. The a wave reflects right atrial contraction. The c wave reflects closure of the tricuspid valve. The v wave reflects the right atrial filling during ventricular systole. The CVP/RAP measurement is the mean of the a wave.

• CVP/RAP values are useful in evaluation of volume status, effect of medication therapy (especially medication that decreases preload), and cardiac function (Table 70-1).

Table 70-1

Central Venous Pressure

Conditions Causing Increased CVP

Elevated intravascular volume

Depressed right-sided cardiac function (RV infarct, RV failure)

Cardiac tamponade

Constrictive pericarditis

Pulmonary hypertension

Chronic left ventricular failure

Conditions Causing Decreased CVP

Reduced intravascular volume*

Decreased mean arterial pressure (MAP)

Venodilation

RV, Right ventricular.

*Although the measured CVP is low, cardiac function may be depressed, normal, or hyperdynamic when there is reduced vascular volume.

• Monitoring parameters from the femoral catheter is not recommended. The catheter is too distant from the right atrium to produce reliable data.