SUCTION OUT CO2 The suction setup that will end up under the cataract patient's drape and remove the accumulated CO2.

CATARACTS + CAPNOGRAPHY
Avoid Inaccurate CO2 Capnography Readings

Cataract extractions usually involve covering the patient with a full-length drape that exposes only the operative eye. These cases are often performed under IV sedation, which obligates us anesthesia providers to closely monitor respiratory status. Nowadays, we often use capnography and measure the end-tidal CO2 via a specialized nasal cannula. But the patient's exhaled CO2 tends to accumulate under the surgical drape. This accumulation can result in "re-breathing" and inaccurate CO2 readings, especially inhaled CO2 readings, on the capnograph. This inhaled level of CO2 is often above the limit set on most gas monitors and can cause alarms to sound repeatedly. I came up with an easy way to eliminate accumulated CO2 under the surgical drape:

• Connect a suction tubing to continuous low suction.
• Clip it to the patient's gown in the chest area.
• To prevent occlusion, place a small paper or plastic cup on the end of the tubing.

Charles A. DeFrancesco, MD
Delmont Surgery Center
Greensburg, Pa.
[email protected]