1. Left and Right Ventricular Assist With the Bio-Medicus Centrifugal Pump 
Nevin M. Katz 
Operative Techniques in Thoracic and Cardiovascular Surgery 
Volume 4, Issue 4, Pages (November 1999)
DOI: /S (07)70123-X
Copyright © 1999 Elsevier Inc. Terms and Conditions

2. 1
The patient is on cardiopulmonary bypass with the arterial perfusion cannula in the ascending aorta and a two-stage venous drainage cannula in the right atrium and inferior vena cava. An intra-aortic balloon pump has been placed via a femoral artery, using the percutaneous Seldinger technique or by direct exposure of the femoral artery. Intra-aortic balloon pumping is continued throughout the period of centrifugal pump assist, as it is felt that the arterial pulsation from the intra-aortic balloon pump may be beneficial.
Operative Techniques in Thoracic and Cardiovascular Surgery 1999 4, DOI: ( /S (07)70123-X)
Copyright © 1999 Elsevier Inc. Terms and Conditions

3. 2
The purse-string suture for the left atrial cannula is placed at the junction of the right superior pulmonary vein with the left atrium or into the body of the left atrium above the level of the inferior pulmonary vein. Additional space for placement of the purse-string suture can be obtained by dissection of the interatrial groove as in mitral valve surgery. The 3-0 polypropylene purse-string suture can be placed as a double-U stitch with a pledget on each side or as a diamond with pledgets at four corners. A second purse-string suture is placed as well, and, in the case of the U stitch, the second purse-string suture is placed at right angles so that pledgets enforce the purse-string sutures at each quadrant. The cannula for pulmonary venous drainage can be placed alternatively in the left atrial appendage or the left ventricular apex. The purse-string suture in the ascending aorta is generally placed on the right anterolateral aspect to facilitate the passage of the cannula around the curve of the arch. Again, two purse-string sutures are placed with pledgets at the four corners. The purse-string sutures for the pulmonary artery cannula are placed just above the level of the pulmonary valve. Again, pledgets are placed at the four quadrants. Generally, the two-stage venous drainage cannula already being used for cardiopulmonary bypass is used for the systemic venous drainage. A second purse-string suture with pledgets may be placed at the cannulation site.
Operative Techniques in Thoracic and Cardiovascular Surgery 1999 4, DOI: ( /S (07)70123-X)
Copyright © 1999 Elsevier Inc. Terms and Conditions

4. 3
The perfusion circuit is assembled and primed by the perfusionist with the lines kept sterile by plastic wrapping. Once the lines are filled and passed onto the surgical field, the lines are divided, and the two segments used for filling the circuits are discarded. Left and right heart lines are distinguished by labels or colored tape.
Operative Techniques in Thoracic and Cardiovascular Surgery 1999 4, DOI: ( /S (07)70123-X)
Copyright © 1999 Elsevier Inc. Terms and Conditions

5. 4
Left atrial cannulation is performed first with the perfusionist adjusting circulatory volume so the heart is relatively filled. A no. 32 straight cannula or a specialized assist cannula can be used. The cannula is filled with the anesthesiologist applying positive pulmonary pressure. Pulmonary artery cannulation is performed next. A noncuffed 6.0- or 6.5-mm Mallinckrodt endotracheal tube (Mallinckrodt Medical, St Louis, MO), or a more specialized cannula, is used. Aortic cannulation is carried out with a long curved cannula so that the tip can be positioned beyond the left subclavian artery. A 6.0-mm or 6.5-mm Mallinckrodt pediatric uncuffed endotracheal tube, or a 24F wire wound arterial perfusion cannula can be employed.
Operative Techniques in Thoracic and Cardiovascular Surgery 1999 4, DOI: ( /S (07)70123-X)
Copyright © 1999 Elsevier Inc. Terms and Conditions

6. 5
Connections are now made except for the right venous drainage connection. Lines are carefully deaired with the anesthesiologist applying positive pressure and saline being poured over the connecting sites. Cardiopulmonary bypass is now discontinued, and left ventricular assist is started. The cannula for the two-stage venous drainage is now disconnected from the tubing of the pump oxygenator and connected to the RVAD circuit of the centrifugal pump. The flows of both pumps are gradually increased, monitoring arterial blood pressure and left atrial pressure and right atrial or central venous pressure. Atrial, ventricular, or atrioventricular pacing may be valuable.
Operative Techniques in Thoracic and Cardiovascular Surgery 1999 4, DOI: ( /S (07)70123-X)
Copyright © 1999 Elsevier Inc. Terms and Conditions

7. 6
The mediastinum is closed using a silastic sheet with the cannulae exiting directly from the mediastinum under the silastic sheet. Usually, posterior and anterior mediastinal drainage tuhes have been brought out through separate incisions. The rubber shod clamps on the tourniquets have been replaced with several large metal clips. The silastic covering is sutured in place with polypropylene. Vaseline gauze is tucked in around the cannula exit sites. Betadine-impregnated ointment is applied to the edges of the silastic covering. A sterile surgical towel is placed over the silastic covering, and the area is then covered with an Ioban Steridrape (3M Health Care, St Paul, MN).
Operative Techniques in Thoracic and Cardiovascular Surgery 1999 4, DOI: ( /S (07)70123-X)
Copyright © 1999 Elsevier Inc. Terms and Conditions