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A comparison of transnasal and transoral endoscopy with small-diameter endoscopes in unsedated patients
1Department of Gastrointestinal Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
Background:
The aim of this study was to compare use and tolerance of transnasal and transoral diagnostic endoscopy with small-diameter endoscopes in unsedated patients.
Methods:
Patients being seen for diagnostic endoscopy were randomly assigned to have an unsedated transnasal or transoral procedure. Two prototype narrow-diameter endoscopes (a 5.3 mm fiberoptic endoscope and a 5.9 mm videoendoscope) were used.
Results:
Of 170 patients (64 women and 106 men) enrolled, 86 underwent transoral and 84 underwent transnasal endoscopy. The procedure was successfully completed using the transoral route in 85 of 86 patients and using the transnasal route in 74 of 84 patients (p = 0.004). Sixteen patients experienced mild epistaxis after transnasal endoscopy. The larger videoendoscope, when compared with the fiberoptic endoscope, accounted for a significantly higher proportion of failures (8 of 41 vs. 2 of 43, p = 0.046) and cases of epistaxis (12 of 33 vs. 4 of 41, p = 0.007). The time taken for transoral endoscopy was shorter than the transnasal route (oral mean 13.7 +/- 0.5 minutes, nasal mean 15.2 +/- 0.6 minutes, p = 0.054). There was no difference between the 2 groups with respect to tolerance of the procedure. From the endoscopist's perspective, the only statistically significant difference between the 2 groups was that endoscope insertion was easier by the oral route (p = 0.007).
Conclusions:
Unsedated transnasal endoscopy with the videoendoscope was less successful compared with the transnasal fiberoptic instrument or when compared with either instrument passed transorally. Use of the larger diameter videoendoscope also resulted in significantly more epistaxis in the transnasal endoscopy group. Endoscopists find transoral introduction of the endoscope easier; this may reflect their relative unfamiliarity with the nasal route. Once intubation has been successfully achieved for either route, patient tolerance is the same.
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