Cardiopulmonary bypass

Cardiopulmonary Bypass

Cardiopulmonary bypass (CPB) is a technique that temporarily takes over the function of the heart and lungs during cardiac surgery, maintaining the circulation of blood and the oxygenation of the body. This process is facilitated by a heart-lung machine, allowing surgeons to perform intricate procedures on the heart while it is stopped.

A heart-lung machine used during cardiopulmonary bypass surgery.

Purpose

The primary purpose of cardiopulmonary bypass is to provide a bloodless field and a motionless heart for the surgeon to perform precise and complex surgical procedures on the heart, such as coronary artery bypass grafting (CABG), heart valve repair or replacement, and congenital heart defect correction.

Components

The CPB circuit consists of several key components: - Oxygenator: Replaces the gas exchange function of the lungs by adding oxygen to the blood and removing carbon dioxide. - Pump: Acts as the heart by propelling blood through the circuit and back into the body. - Heat Exchanger: Controls the temperature of the blood, allowing for hypothermia or normothermia as required by the surgical procedure. - Filters: Remove air bubbles and particulate matter from the blood to prevent embolism.

Process

The process of cardiopulmonary bypass involves: 1. Cannulation, where tubes are inserted into the heart or great vessels to divert blood away from the heart to the heart-lung machine. 2. Initiation of CPB, where blood is oxygenated and circulated by the machine, bypassing the heart and lungs. 3. Maintenance of physiological parameters, including blood pressure, oxygen and carbon dioxide levels, and body temperature, throughout the surgery. 4. Weaning off CPB, gradually transferring the circulatory and respiratory functions back to the patient's heart and lungs.

Risks and Complications

While CPB is a lifesaving procedure, it is associated with several potential risks and complications, including: - Systemic inflammation response syndrome (SIRS) - Coagulation disorders - Neurological complications, including stroke and cognitive deficits - Organ dysfunction, such as renal failure or pulmonary complications

Advancements

Recent advancements in cardiopulmonary bypass technology focus on minimizing the adverse effects associated with CPB. These include the development of miniaturized CPB circuits, which reduce the amount of blood contact with foreign surfaces, and techniques for reducing inflammation and organ dysfunction.

External Links

• The Society of Thoracic Surgeons - Cardiac Surgery and Cardiopulmonary Bypass
• American Heart Association - Cardiovascular Disease

References

Cardiopulmonary bypass Resources
Latest articles Most recent articles Ongoing trials	Wikipedia