medical procedure is a medical procedure
which is carried outside the body.
It is usually a procedure in which blood is taken from a patient's circulation to have a process applied to it before it is returned to the circulation. All of the apparatus carrying the blood outside the body is termed the extracorporeal circuit
It is also used to refer to extracorporeal shock wave lithotripsy
(ESWL), which is unrelated to other extracorporeal therapies, in that the device used to break up the kidney stones is held completely outside the body, whilst the lithotripsy itself occurs inside the body.
It is also used in extracorporeal radiotherapy, where a large bone a tumour is removed and given a dose far exceeding what would otherwise be safe to give to a patient.