Biotelemetry and patient monitoring are two fields closely related, and should contribute to the contiuous measurement of physiological parameters from patients with little impediment. In anesthesia the requirement of minimal impediment is less important. Here wireless transmission has two advantages of great importance, namely: minimization of the risk of electricl shock by the incorporation of batteries and a complete separation of the patient and the recording equipment, and the possibility of connecting the patient to the measuring equipment before transporting him into the operating theatre. The telemetry of several parameters, especially of the cardiovascular and respiratory system is described, including the telemetry of blood-pressure, blood flow, cardiac output, ECG and arterial PO2, as well as respiratory flow, respiratory PO2 and its derived values, such as tidal volume, ventilation and oxygen uptake.