Cardiopulmonary complications during gastroscopy in patients with chronic respiratory failure undergoing long-term home oxygen therapy

Background and Study Aims: Gastric ulcer and hemorrhage are major complicat ions in patients with chronic respiratory failure, but upper GI endoscopy t ends to be avoided because of possible cardiopulmonary events. This study w as designed to evaluate hypoxemia and subsequent cardiac complications duri ng gastroscopic procedures in patients with chronic respiratory failure und ergoing long-term home oxygen therapy (LHOT). Patients and Methods: Gastroscopy was carried out in 10 patients undergoing LHOT and 10 age-matched control subjects without pulmonary diseases. Oxyge n saturation and cardiac arrhythmias before and during gastroscopy were mon itored, Patients were given 10 mg intramuscular scopolamine butylbromide an d local anesthesia using 100-300 mg lidocaine gel 15 minutes before the pro cedure. Each patient continued to receive oxygen via a nasal cannula in the same dosage as their daily use. Results: Decrease in oxygen saturation during endoscopic procedure was sign ificantly greater in patients undergoing LHOT (from 95.9 +/- 0.9 to 93.4 +/ - 1.7%) compared with control subjects (from 96.7 +/- 0.4 to 96.2 +/- 0.4%) . There was a significant correlation between the degree of hypoxemia and t he oxygen dosage required for their daily treatment in the patients (r = 0. 727, P < 0.02). Conclusions: These results indicate that the degree of respiratory failure influences the degree of decrease in oxygen saturation during gastroscopy. It is suggested that use of the nasal route for oxygen supply may be one of the major causes of the hypoxemia.