The hospitals in which those procedures are carried out are designed and built by human beings. They design, manufacture, and maintain all the equipment used in the diagnosis of patients, and in their anaesthetic, surgical and intensive care. Human beings decide if a child will or will not undergo pediatric cardiac surgery.
Human beings make errors.
We make errors in the design and construction of systems. Thus, the health-care system represents everything from patients, personnel, the equipment and the environment within which care is provided, the organizations that provide that care, and the regulatory agencies, such as the government, that legislate or otherwise regulate the provision of health care. We make errors in the design and construction of technology used in the system, and we make errors when we maintain those technologies. We make errors when we plan and when we execute plans. We make errors when we execute individual tasks that are part of a larger plan.