How Do We Keep People Alive During Heart Transplants?
In heart transplants, one of the most complex and critical procedures in medicine, ensuring patient survival is paramount. This is primarily achieved through the use of a heart-lung machine, also known as cardiopulmonary bypass, a technology that has evolved significantly over the past 75 years.
Heart-Lung Machine: A Lifeline During Heart Transplants
The heart-lung machine is a critical tool that supports the patient during a heart transplant. It temporarily takes over the functions of the native heart and lungs, allowing the medical team to perform the transplant without the risk of insufficient blood flow or oxygenation. The machine pumps blood, oxygenates it, and circulates it throughout the body until the new heart is implanted and restarted.
Key Techniques for Safeguarding Patient Life During Heart Transplants
Several advanced techniques have been developed to maintain cellular life and support the patient during the operation. Stopping the Heart: The native heart is stopped, and the heart-lung machine takes over its functions. Cooling the Heart: The heart and body are cooled to slow down cellular metabolic processes, reducing the risk of damage. Timeliness in Surgery: Surgical techniques are developed to complete the necessary procedures efficiently, minimizing risks. Reversing Cooling: After the surgery, the cooling process is reversed, and the heart is restarted to ensure it functions correctly.
The Development of Cardiopulmonary Bypass
The use of cardiopulmonary bypass in heart transplants is not a recent innovation. It has evolved over several decades, with its roots in animal experiments and early human applications. As surgical techniques and equipment improved, more complex surgeries became feasible, and success rates rose. Over time, what was once a groundbreaking procedure has become routine in medical practice.
Techniques for simple operations were first developed, and as experience grew, more advanced equipment was designed to handle complex procedures. This evolution has led to a significant increase in the success rates of heart transplants, making them a more viable option for patients with severe heart conditions.
Monitoring and Maintaining Patient Life
During the process, the heart-lung machine is used to circulate and oxygenate the blood for a period of about two hours, providing temporary support until the new heart takes over. In cases where there is no heart transplant and the heart is not beating, the heart-lung machine provides the necessary support to ensure the patient's survival and brain perfusion.
Conclusion: Heart transplants are complex and risky, but with the right surgical techniques and equipment, the risk of patient death has significantly decreased. The heart-lung machine plays a crucial role in this process, ensuring that patients can undergo the procedure safely and successfully.