Introduction Intubation failure (IF) occurs when a trained endoscopist is unable to progress via the oropharynx and into the upper oesophagus. The incidence is unknown, but estimated at 1.8%.^[1] There have been no studies exploring IF and follow-up findings. We aimed to assess the incidence, causes and predictors of IF, and follow-up findings.

Method We retrospectively identified all gastroscopies performed at a district general hospital between August 2010–2016, and reviewed cases with IF. Procedural data were collected, and patients allocated into groups based on ‘failure to tolerate’ (e.g. pulling out scope, anxiety) or ‘failure to progress’. Barium, computed tomography (CT), and repeat gastroscopy findings were reviewed to assess for structural causes of IF. Statistical analyses were made using Pearson’s chi².

Results The incidence of IF was 0.95% (248/26130). 238 patients were identified, with a mean age of 63.2 (SD 16.1), with ‘failure to progress’ in 41 and ‘failure to tolerate’ in 197. Subsequent investigations included barium radiology (59.7%, n=142), CT (21%, n=50), repeat gastroscopy (29.4%, n=70) and no further investigations (19.7%, n=47). Structural pharyngeal abnormalities were detected in 41 (28.9%), comprising of cricopharyngeal hypertrophy (CPH) [49%], Zenker’s diverticulum (ZD) [14.6%], pharyngeal web (12.2%), ZD with CPH (9.8%), cervical spondylosis (7.3%) and other (7.3%). Endoscopist status was a predictor of IF (OR for medical vs. non-medical endoscopist 0.7, 95% CI: 0.5–0.9, p=0.007). Within the IF cohort, predictors of structural causes on barium radiology included: dysphagia (OR 5.5, 95% CI: 2.5–11.8, p<0.001), failure to progress (OR 5.2, 95% CI: 2.3–12.0, p<0.001) and age ≥65 (OR 4.0, 95% CI: 1.8–8.9, p<0.001). Repeat gastroscopy was successful in 63/70 (2 using nasendoscope) after increasing midazolam dosage (mean increase=1.5 mg, 95% CI: 1.0–2.0 mg, p<0.001). Diagnostic yield for barium radiology, CT and repeat gastroscopy were 69.0%, 54.0% and 64.3% respectively. The concordance of endoscopic indication and pathology on further investigation for IF was 110/192 (57.3%). In patients undergoing barium radiology and repeat gastroscopy, the false negative rate for endoscopy was 17/30 (56.7%), consisting of pharyngeal pathology (n=9), dysmotility (n=4) and significant reflux (n=4).

Conclusion We present novel data regarding IF, and report an incidence of ≈1%. Patients should be investigated further owing to high risk of underlying pathology, particularly if associated with age ≥65, dysphagia, and failure of endoscopic progression. Barium radiology is comparable to repeat gastroscopy in terms of diagnostic yield, and may be more helpful in evaluating pharyngeal and functional pathology.

Reference

1. . Ponchon T, GIE, April2000;51(4):AB275.

Disclosure of Interest None Declared