Abstracts
1998 Digestive Disease Week

#968

INTRATRACHEAL LONG-TERM PH MONITORING: A NEW METHOD TO EVALUATE EPISODES OF SILENT ASPIRATION IN PATIENTS AFTER ESOPHAGECTOMY AND GASTRIC PULL UP. Kauer WKH, Stein HJ, Bartels HJ, Siewert JR Department of Surgery, Technical University Munich, Germany.

The aspiration of gastric contents is dangerous and often difficult to recognize but can lead to postoperative pulmonary complications in patients who had undergone esophagectomy and gastric pull up. We investigated, whether intratracheal long-term pH monitoring is a feasible and reliable method to evaluate aspiration of gastric contents in these patients.

Intratracheal pH monitoring was performed in 16 patients (m:f=13:3, median age 59.5 years, range 44-69 years) with esophageal carcinoma following esophagectomy (transmediastinal n=9, transthoracic n=7) and gastric pull up (anterior mediastinum n=6, posterior mediastinum n=7) Long-term pH monitoring was carried out during the first 72 hours postoperatively. Immediately after transferring the patient to the Intensive Care Unit a glass pH probe was inserted 1 cm below the distal end of the naso-tracheal tube. After extubation (generally 24 hours postoperatively) the probe was positioned 1 cm distal of the vocal chords under bronchoscopic guidance. Analysis of the data was done utilizing commercially available software. An aspiration episode was defined by a drop of the pH under 4.

All patients except one tolerated the probe without any difficulties. In 12/15 patients (80%) aspiration episodes could be detected (5/8 patients after transmediastinal esophagectomy, 7/7 after transthoracic esophagectomy; 2/5 with reconstruction in the anterior mediastinum, 10/10 with reconstruction in the posterior mediastinum). The number of aspiration episodes was significantly higher during the first postoperative day (p=0.03) compared to the second and third day. Two patients developed a pneumonia later in the postoperative course. Both patients had aspiration episodes detected by pH monitoring immediately postoperatively or after extubation.

Intratracheal pH monitoring is a safe, feasible and well tolerated method to detect aspiration episodes in patients after esophagectomy and gastric pull up. Aspiration of gastric contents is a common phenomenon especially after transthoracic esophagectomy and gastric pull up in the posterior mediastinum. It seems to correlate with the development of postoperative pneumonia.

Copyright 1996 - 1998, SSAT, Inc. Revised 29 June 1998.