Which of the following insufflation gases should not be used with radiofrequency (RF) electrosurgery ?

CO2 is the most commonly used gas for peritoneal insufflation, but alternative gases are available. Nitrous oxide has been used for procedures performed under local anesthesia because it does not cause the acid-base disturbances associated with CO2 pneumoperitoneum and may cause less postoperative pain. However, it suppos combustion, and its use is not recommended in procedures that require RF electrosurgery. Use of ine gases, such as helium and argon, also prevents acid-base problems; however, these agents are rarely used because they are expensive and have low solubility, which may increase the risk for gas embolism.