Managing a venous air embolism

Nursing, Oct 1998 by Jones, Robert C

WHENEVER YOU INSERT OR REMOVE A CENTRAL VENOUS catheter, your patient is at risk for a potentially fatal venous air embolism. Most air emboli occur when air enters the vascular system through a central venous catheter (rarely through a peripheral I.V. line). Here's what happens: A break occurs in the I.V. system above the level of the heart. If the patient coughs, sneezes, cries, laughs, or takes a deep breath, the change in intrathoracic pressure can draw 10 to IS cc of air into the venous system as a bolus.

Once air enters the venous system, it travels to the heart. There, it creates a lock at the pulmonic valve, preventing blood from being ejected from the right atrium.

A patient with a venous air embolism will exhibit respiratory distress, increased heart rate, cyanosis, a drop in BP, and a sudden change in level of consciousness and may complain of back or shoulder pain. On auscultation, you may hear a churning murmur over the precordium.

If you suspect that your patient has an air embolism, pinch off the catheter or otherwise cover the catheter insertion site to prevent more air from entering the venous system. Place the patient on his left side in Trendelenburg's position to keep the air in the right atrium. Call for help and have a colleague get the physician and a respiratory therapist. Check your patient's vital signs and administer oxygen. Attach your patient to a portable cardiac monitor and a pulse oximeter.

The physician may aspirate the air from the right atrium using an intracardiac needle. Monitor the patient closely.

The best defense against air embolism is prevention. Prime the I.V. tubing before starting an infusion and use twist-lock connections or tape all connections securely. Use infusion pumps with air-in-line alarms and air-elimination filters. When changing tubing, clamp the catheter. During insertion or removal of a central I.V. line or tubing changes, have the patient lie flat and ask him to perform a Valsalva maneuver.

After removing a central venous catheter, use a gel-based antibiotic ointment or petroleum jelly gauze to cover the insertion site and area just around it. Cover with a dressing. Inspect the site for epithelization every 24 hours, and document your findings. A scab, once formed, will seal the site.

BY ROBERT C. JONES, RN, BSN

Associate Clinical Educator

Perivascular Nurse Consultants, Inc.

Rockledge, Pa.