Cannulation for CPB

• Aortic Cannulation: A cannula is inserted into the ascending aorta, which carries oxygenated blood away from the heart. This cannulation site is typically used for arterial drainage during CPB.

• Venous Cannulation: Venous cannulas are placed in the right atrium or superior vena cava to return deoxygenated blood from the body to the CPB circuit. Common sites for venous cannulation include the right atrium and superior vena cava.

• Additional Cannulation: In some cases, additional cannulas may be required, such as ventricular venting cannulas to decompress the heart or coronary sinus cannulas for myocardial protection.

The size of the cannulas used depends on the patient's age, size, and the specific surgical procedure. Larger cannulas are used for adults, while smaller ones are used for pediatric patients.

• The choice of cannulation technique depends on the surgeon's preference, patient anatomy, and the specific procedure. Common techniques include direct cannulation and side-arm graft cannulation.

• Direct cannulation involves inserting the cannula directly into the vessel. This technique is often used for the aortic cannula.

• Side-arm graft cannulation involves creating a small incision in the vessel and attaching the cannula with a graft to provide a secure connection.

During CPB, various monitoring devices, such as pressure sensors and flow meters, are used to control and maintain blood flow, pressure, and oxygenation. This helps ensure adequate perfusion to the body's organs and tissues.

To prevent blood clotting within the CPB circuit, anticoagulants like heparin are administered to the patient. The dosage is carefully monitored to maintain an appropriate level of anticoagulation. Click here to learn more about heparin.

During CPB, the heart is often arrested temporarily using a cardioplegia solution. This allows the surgeon to work on the heart while it is not beating. The solution is delivered through the coronary sinus cannula or directly into the coronary arteries.

After the surgical procedure is completed, the cannulas are carefully removed, and the circulatory system is gradually weaned off CPB support. The heart is typically restarted, and the patient's natural circulation is restored.

​

​Cannulation for cardiopulmonary bypass is a critical step in ensuring the safety and success of cardiac surgeries. It requires careful planning, precise placement of cannulas, and vigilant monitoring throughout the procedure to maintain the patient's well-being. The goal is to provide optimal support to the circulatory system while allowing the surgeon to perform the necessary cardiac repairs.