Research and development of semi-automatic circulation control system for cardiopulmonary bypass

Abstract

Asako Tokumine is amongst a number of researchers who believe automation marks the next step in cardiac surgery, with both safety and cost benefits to be reaped. The actual flow and oxygenation of blood is critical during cardiac surgery and even small changes can have profound effects. Automation has reached some areas of surgery and is seen as the future of the field, including secondary processes such as blood control. However, many supporting parts of these procedures are still controlled by humans, making them expensive and time-consuming, but this may soon change. Automation of surgical procedures is regarded as a huge step forward, but also one that carries significant risk, since the patient is placed in the hands of a non-human system. Plainly, medical automation is an effective means of ensuring trouble-free operation provided the system is sufficiently robust and any problem areas are resolved prior to commercial operation. The positive aspects of robotic surgical theatres don't end there either. Aside from high precision surgical techniques, the use of robot arms is already leading to smaller theatres that are easier to maintain and keep sterile, while minimising risk to the patient. This also applies to secondary systems too, and there is now much work being conducted on automating areas such as atmosphere control, imaging systems, and increasingly, life support. The circulation control system is one of the most important non-invasive control systems used alongside the actual surgical unit, and this is an area in which Tokumine believes automation would be of huge benefit. Tokumine's background is in the cardiopulmonary field, having made extracorporeal circulation her main area of study since graduation. Having been at the forefront of the development of a ventricular assist device (VAD) - an implantable pump system designed to help suffers with weakened hearts to live fuller lives - she has now turned her attention to designing a semi-automatic blood handling and delivery system that could be used within the surgical environment. Cardiopulmonary bypass is used in coronary bypass heart surgery to remove the added difficulty of operating on the moving heart. Operations requiring the opening of the chambers of the heart require the use of a bypass machine to support the circulation during the procedure. The machine pumps the blood, and, using an oxygenator, allows red blood cells to pick up oxygen, as well as allowing carbon dioxide levels to decrease. This effectively mimics the function of the heart and lungs and maintains life systems for the patient.