The Bicircuit System: Innovative Perfusional Options for Surgical Treatment of the Thoracic Aorta

Purpose: Surgical treatment of the thoracic aorta may become challenging when a rapid switch from left heart bypass (LHB) to cardiopulmonary bypass (CPB) is required.

Description: We designed a BICIRCUIT system using a centrifugal pump, a heparinized CPB circuit with a hollow fiber oxygenator, two 3/8 x 3/8 x 3/8 connectors (one placed at the bell inlet draining blood from the left atrium or the venous reservoir and the second placed at the bell outlet directing blood to the oxygenator or femoral artery). Our priming volume was 1100 mL; when switching from LHB to CPB, no additional priming volume was required. The inlet cannula was inserted in the left atrium (for LHB) or femoral vein (for CPB); the outlet cannula was placed in the femoral artery.

Evaluation: We used the BICIRCUIT in 18 patients: 7 patients with a thoracoabdominal aneurysm, 7 patients with a traumatic rupture of isthmic aorta, and 4 patients with a Stanford type B aortic dissection. Conversion to CPB was required in 3 patients because of hemodynamic deterioration and in 1 patient because of hypothermic circulatory arrest. As we observed progressive worsening of blood gases in another patient during LHB, we also used the blood oxygenator without changing the position of the cannulas. No system failures were observed. Postoperative spinal disturbances did not develop in any patients. All patients were successfully discharged.

Conclusions: Our BICIRCUIT system offers three different options: LHB, LHB along with blood oxygenation, and CPB. Each option can be safely achieved and adds to the armamentarium of surgeons and perfusionists in caring for patients with pathology of the thoracic aorta.