Sudden Increase in EtCO2 During Upper Endoscopy Under General Endotracheal Anesthesia Suggests the Presence of Tracheoesophageal Fistula: A Case Report.

The authors reported a case where they were able to diagnose  tracheoesophageal fistula in a patient with lung cancer status post palliative chemoradiotherapy and esophageal stenting for malignant stenosis.   The provisional diagnosis of  tracheoesophageal fistula could not be confirmed by barium esophagram, which is performed as a standard procedure.  The patient received general anesthesia for subsequent esophagogastroduodenoscopy.  the presence of a fistula was verified by capnography, given extreme elevations in end-tidal CO₂ concentrations during endoscopic CO₂ insufflation.

Comment Bhavani Shakar Kodali MD

The end tidal PCO2 concentrations dramatically increased to 200 mm Hg due to the flow of CO2 gas from esophagus and stomach into the trachea.  The discussion between the anesthesiologist and the gastroenterologist prompted a good look at the esophagus and a  tracheoesophageal fistula was confirmed.  This is yet another advantage of using capnography in all gastroenterology procedures.