A trocar assembly including an obturator, an access cannula, and a reservoir is provided. The access cannula defines a lumen therethrough configured to selectively receive the obturator. The reservoir is configured to be selectively coupled to the obturator such that the reservoir is in fluid communication with a hollow interior portion of the obturator. An obturator is also provided including an elongate body and a connection point. The elongate body extends between proximal and distal portions and is configured to be received within an access cannula. The elongate body defines a hollow interior portion therein. The connection point is disposed on an exterior portion of the elongate body and is configured to be selectively coupled to a fluid reservoir. Rapid expansion of fluid within the hollow interior portion causes tissue in contact with the access cannula to freeze thereto. A method of performing surgery is also provided.