Abstract: The present invention reliably provides a lung protection function for an electrocautery device by unitizing an automatic bovie activation/inactivation unit. The lung protection unit utilizes a threshold calculated from the maximum and minimum airway pressure signal in a ventilator or an anesthesia machine to inactivate the bovie before the maximal lung expansion reaches the bovie during a thoracic surgery. Bovie is activated again as soon as the lung expansion level decreases to below the threshold level. This device is an attached optional unit or can be built into a standard electrocautery equipment.

Abstract: A method for determining a patient's left ventricular pressure waveform without placement of a catheter inside the left ventricle, including converting the patient's ejection phase waveform of the peripheral arterial pressure by using a standardized ejection correlation curve, and converting the filling phase waveform of the pulmonary capillary wedge pressure by using a standardized filling correlation curve, into two portions of the left ventricular pressure waveform, and then connecting the two portions together with two straight lines to complete the left ventricular pressure waveform.