TRIPASS XR تري باس

 

Chapter 33 ■ Extracorporeal Membrane Oxygenation Cannulation and Decannulation 219

A. Double-Lumen VV Catheters

1. Kendall 14-Fr catheter (Kendall Health Care Products,

Mansfield, Massachusetts)

2. OriGen 12-, 15-, and 18-Fr catheters (OriGen

Biomedical, Austin, Texas)

3. Avalon Elite DLC, 13- to 31-Fr catheter (Avalon

Laboratories LLC, Rancho Dominguez, California)

Note: The Avalon catheter requires insertion under

ultrasound or fluoroscopy guidance; refer to company

recommendations at www.avalonlabs.com

B. Advantages of VV Bypass

1. Provides excellent pulmonary support

2. Avoids carotid artery ligation

3. Oxygenated blood enters pulmonary circulation.

4. Particles coming from the ECMO circuit enter the

venous circulation instead of the arterial circulation.

C. Disadvantages of VV Bypass

1. Lack of cardiac support

2. ECMO support is dependent on the patient’s cardiac

function.

3. Catheter position and rotation are extremely critical.

4. Amount of recirculation

D. Cannulation Technique

The cannulation technique for VV ECMO is essentially

the same procedure as venous cannulation for VA ECMO,

with the following exceptions.

1. Both internal jugular vein and carotid arteries are identified and dissected free, although the internal jugular

vein is the only vessel cannulated with the doublelumen VV catheter. Both vessels are isolated in case a

rapid conversion to VA bypass becomes necessary. A

silastic loop may be tied loosely around the artery to

facilitate potential conversion to VA flow.

2. The cannula is advanced with the lumen, which will

carry oxygenated blood (“arterial side”) upward and

anterior to the venous side of the double-lumen

(Fig. 33.8).

Caution: Avoid bending the catheter or creating a

“crimp” in the catheter.

Correct positioning of the catheter helps direct the

oxygenated blood return toward the tricuspid valve,

thus minimizing the recirculation of the oxygenated

blood back to the ECMO circuit.

3. The proximal end of the internal jugular vein is also

cannulated for cephalad drainage, that is, a jugular

bulb catheter. This catheter is connected to the venous

tubing of the ECMO circuit via a Luer connector. For

this, we use a custom-made Carmeda heparin-coated

Bio-Medicus venous catheter, made specifically for use

as a cephalad catheter.

This allows additional venous drainage to the

ECMO circuit, prevents venous congestion, and also

allows for cephalic venous saturation measurement.

4. If using a jugular bulb catheter to measure cerebral

saturations, care should be used when entering the circuit; air will draw into the venous side of the circuit

rapidly if a stopcock is loose or is left open.

E. Placing Patient on the Extracorporeal

Membrane Oxygenation Circuit

The circuit has been previously primed with packed cells/

albumin. The priming procedure and the surgical placement of the ECMO catheters should be timed so that the

two are completed at the same time. Priming of the circuit

is beyond the scope of this chapter.

1. Fill catheters with sterile saline. Connect them to the

ECMO circuit by inserting the 0.25- × 0.25-inch connectors into the tubing as the assistant drips sterile

saline into the ends of the circuit tubing and the catheter, to ensure that all residual air is eliminated prior to

connection.