Gas transport resulting from plasma-scalpel surgery

The extent of absorption and the intravascular itinerary of plasma-scalpel operating gas have been investigated by monitoring the intravascular and exhaled argon partial pressures during canine hepatic surgery. The blood-gas analysis was performed continuously, using a mass spectrometer to measure dissolved argon, and, periodically, using a gas chromatograph to quantify all argon ingested, including emboli. To quantify the amount of argon lost through the pulmonary circulation, monitoring took place in the right atrium and the aorta. Experimental results show that the amount of argon absorbed at the incision site and transported through the bloodstream may increase the dissolved argon concentration in the right atrium by as much as 150%. The results also indicate that argon may be present as emboli in the bloodstream, but that argon storage in the tissues is insignificant. The argon concentration in the aorta does not noticeably increase; hence the excess argon is exhaled within one circulation through the pulmonary circuit. These observations were substantiated by the use of an ultrasonic Doppler flowmeter to check for the presence of gas emboli at various locations.