Electrosurgery-induced generation of gases: comparison of in vitro rates of production using bipolar and monopolar electrodes.
OBJECTIVE
To compare rates of production of gases generated by VersaPoint bipolar hysteroscopic vaporizing electrodes using normal saline and monopolar vaporizing electrodes using 1.5% glycine.


METHODS
In vitro study (Canadian Task Force classification II-1).


METHODS
Laboratory.


METHODS
Bovine cardiac muscle.


METHODS
Fresh morbid bovine cardiac muscle was fully immersed in normal saline for the bipolar system and in 1.5% glycine for monopolar systems. Loop and bulk vaporizing electrodes were activated by radiofrequency electrosurgical units (ESUs) appropriate for each system, at standard powers and at settings higher than those in clinical use.


RESULTS
Rates of gas production were calculated and data analyzed by analysis of variance. For bulk vaporizing electrodes, the highest gas production rates at standard settings occurred with monopolar electrodes and the Force 2 generator at 300 W, and the Force FX at 200 W. At slightly higher than standard 200-W settings, the VersaPoint bipolar bulk vaporizing electrode was associated with lowest gas production rates in this category. Although there were statistically significant differences between loop electrodes, the magnitude remained small at similar ESU settings, and differences are thought to be clinically insignificant.


CONCLUSIONS
Rates of gas production in this model appeared to vary most with ESU power output settings and relatively little with electrosurgical modality (bipolar or monopolar).
Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California, Los Angeles, USA.
Malcolm G
MG
Munro
Andrew I
AI
Brill
Thomas
T
Ryan
Scott
S
Ciarrocca
D000818:Animals; D002417:Cattle; D046508:Culture Techniques; D004566:Electrodes / Q000009:adverse effects*; D004598:Electrosurgery / Q000009:adverse effects* / Q000379:methods; D004618:Embolism, Air / Q000209:etiology / Q000517:prevention & control*; D004869:Equipment Safety; D005740:Gases; D015907:Hysteroscopy / Q000009:adverse effects; D023421:Models, Animal; D009206:Myocardium; D018570:Risk Assessment
D005740:Gases