A styletted tracheal tube with a posterior-facing bevel reduces epistaxis during nasal intubation: a randomized trial

Epistaxis is a common complication of nasal intubation. Ease of insertion of the tracheal tube may be influenced by bevel orientation and tip bending. We examined ease of insertion and epistaxis with two tubes with different orientations and with or without a stylet to modify tip bending.

Two hundred patients scheduled to undergo oral or maxillofacial surgery were randomized into four groups according to method of nasal intubation used after induction of anesthesia. In one group, a Portex(®) tracheal tube was inserted with bevel facing left (Portex Group). In the second group, a Parker Flex-Tip(®) tube (Parker Group) was inserted with the bevel facing posteriorly, and in the last two groups, a stylet bent at 60° anteriorly was used with the Portex tube (Stylet-Portex Group) or Parker tube (Stylet-Parker Group). When the tube advanced without resistance, insertion was defined as "smooth", and when resistance was encountered, insertion was defined as "impinged". Severity of epistaxis was evaluated as none, mild, moderate, or severe.

Smooth insertion was observed in 60% of patients in the Portex Group; 80% in the Parker Group; 100% in the Stylet-Portex Group; and 100% in the Stylet-Parker Group. Epistaxis was found in 50%, 24%, 20%, and 4% of patients, respectively. The styletted tip (difference: 30%; 95% confidence interval [CI]: 20.3 to 38.5; P < 0.0001) was found to improve ease of insertion. Both the posterior-facing bevel (difference: 21%; 95% CI: 9.0 to 32.1; P = 0.0005) and stylet (difference: 25%; 95% CI: 13.1 to 35.9; P < 0.0001) contributed significantly to absence of epistaxis.

Using a styletted tracheal tube with a posterior-facing bevel improves ease of insertion through the nasopharynx and decreases the severity of epistaxis during nasal intubation.

UMIN Clinical Trials Registry (UMIN-CTR), UMIN000011327.