UNIVERSITY OF ARKANSAS FOR MEDICAL SCIENCES           PROCEDURE:     176

MEDICAL CENTER                                          EFFECTIVE:        12/07

REVISION:

PROCEDURE                                               APPROVED:        12/07

PROCEDURE FOR CENTRAL VENOUS/RIGHT ATRIAL PRESSURE MONITORING USING WATER MANOMETER METHOD

PURPOSE:      To ensure standardization of CVP Measurement Using Water Manometer Method

EQUIPMENT:   

1.  Water Monitoring System

2.  IV Pole/IV Fluid (Normal Saline-500mg)

3.  Water Manometer

4.  Indelible Marker

5.  Level 

NURSING ACTION:

PROCEDURE STEPS:

1.      Wash Hands

2.      Locate the phlebostatic axis

A.     Identify the fourth intercostal space on the edge of the sternum. 

B.     Draw an imaginary line along the forth ICS laterally, along the chest wall.

C.     Draw a secondary imaginary line from the axilla downward, midway between the anterior and posterior chest walls. 

D.     Where these two lines cross is the level of the phlebostatic axis.

KEY POINT:  Once the phlebostatic axis has been identified, the nurse should mark the patient’s skin with an indelible marker at the level.  This will ensure that future readings are taken at the same location. 

3.      Position the patient in the supine position with the head elevated.

4.      Attach the water manometer to the CVP tubing system and flush the tubing with normal saline while the system is off to the patient.

5.      Place the zero level of the water manometer at the level of the phlebostatic axis

KEY POINT:  Level the water manometer for accurate measurements.  Ensures accuracy in measurement.

6.      Turn the water manometer stopcock open to the flush solution

7.      Open the IV tubing roller clamp so that fluid flows from the IV fluid solution into the water manometer.

A.     Fill the manometer two-thirds full or above the level of the expected CVP measurement.

B.     Ensure that there are no air bubbles in the manometer

C.     Close the roller clamp on the IV tubing.

KEY POINT:  Underfilling the water manometer will result in an inaccurate measurement. 

8.      Turn the water manometer stopcock open to the patient and closed to the IV solution

9.      Observe the fluid column closely.  It should fluctuate with the patient’s respiratory cycle

KEY POINT:  If the manometer is allowed to empty, air may enter the patient. 

10.  The fluid column should fall quickly and then fluctuate gently at the point where the fluid column equalizes with the right atrial pressure.  Measure the CVP reading at the end expiration.

11.  Turn the water manometer stopcock open to the flush solution and the patient, and reestablish the IV fluid infusion.

12.  Wash hands. 

REFERENCES:  American Association of Critical Care Nurses (2005). AACN Procedure Manual for

Critical Care (5^th ed).    St. Louis, Missouri: Elsevier Saunders. Pg. 506-513, 591-601.

RESOURCE PERSON(S):  Pat House, RN