Risk factors affecting the difficulty of fiberoptic nasotracheal intubation

Abstract

Background: The success rate of intubation under direct laryngoscopy is greatly influenced by laryngoscopic grade using the Cormack-Lehane classification. However, it is not known whether grade under direct laryngoscopy can also affects the success rate of nasotracheal intubation using a fiberoptic bronchoscpe, so this study investigated the same. In addition, we investigated other factors that influence the success rate of fiberoptic nasotracheal intubation (FNI). Methods: FNI was performed by 18 anesthesiology residents under general anesthesia in patients over 15 years of age who underwent elective oral and maxillofacial operations. In all patients, the Mallampati grade was measured. Laryngeal view grade under direct laryngoscopy, and the degree of secretion and bleeding in the oral cavity was measured and divided into 3 grades. The time required for successful FNI was measured. If the intubation time was > 5 minutes, it was evaluated as a failure and the airway was managed by another method. The failure rate was evaluated using appropriate statistical method. Receiver operating characteristic (ROC) curves and area under the curve (AUC) were also measured. Results: A total of 650 patients were included in the study, and the failure rate of FNI was 4.5%. The patient's sex, age, height, weight, Mallampati, and laryngoscopic view grade did not affect the success rate of FNI (P > 0.05). BMI, the number of FNI performed by residents (P = 0.03), secretion (P < 0.001), and bleeding (P < 0.001) grades influenced the success rate. The AUCs of bleeding and secretion were 0.864 and 0.798, respectively, but the AUC of BMI, the number of FNI performed by residents, Mallampati, and laryngoscopic view grade were 0.527, 0.616, 0.614, and 0.544, respectively. Conclusion: Unlike in intubation under direct laryngoscopy, in the case of FNI, oral secretion and nasal bleeding had a significant effect on FNI difficulty than Mallampati grade or Laryngeal view grade.

Learning curve for flexible bronchoscope-guided orotracheal intubation for anesthesiology residents: A cumulative sum analysis

“…The nasal route is often used on patients with poor mouth opening or a large tongue as it courses past the nasopharynx with less obstruction by the tongue [ 21 ]. Awake flexible bronchoscope-guided intubation is strongly recommended in patients with anticipated difficult airways [ 2 , 6 , 22 , 23 ]. In this study, orotracheal intubation was performed in anesthetized apneic patients with normal airways as it is considered more difficult than nasal intubation of the awake patient.…”

“…A previous study showed anesthesiologists achieved competence (first-attempt intubation success rates > 90% and intubation time of ≤ 2 minutes) in fiberoptic laryngoscopy and intubation in anesthetized patients with normal airways after 10 procedures [ 22 ], and all the trainees learned at the same rate. Several reasons may explain the disparate findings between the prior report and the present study.…”

A learning curve of a novel multimodal endotracheal intubation assistant device for novices in a simulated airway: a prospective manikin trial with cumulative sum method

“…Due to the limitation of the manikin, the tongue was unable to be inflated to simulate tongue edema. At the same time, it also cannot simulate the clinical scenario of sputum and secretions blocking the view field ( 36 ), so the advantage of multimodal tracheal intubation aids was not fully realized. The initial prototype MEIAD used in this study has not yet been put into production and clinical application.…”

Nasotracheal Intubation After Transsphenoidal Surgery: A Case Report

“…However, the surgical procedure, including tracheostomy and a submental approach, may have potential complications, including bleeding, infection, and hypertrophic scarring [12], which can be relatively notable in patients who undergo elective orthognathic surgery. Fiberoptic nasotracheal intubation was also considered; however, anatomical abnormalities, bleeding, and secretion in the oral and pharyngeal cavity can cause the failure of intubation or accidental intracranial placement of the fiberoptic scope itself [16,19]. Therefore, we devised a simple and safe technique using a balloon catheter as an alternative to fiberoptic intubation.…”

“…Submental intubation can also cause hemorrhage, infection, orocutaneous fistula, and injury to the sublingual or lingual nerves [8,12]. Fiberoptic nasotracheal intubation is a standard technique for the management of patients with problematic airways [13]; however, the failure rate of fiberoptic intubation when performed by skillful and experienced anesthesiologists is still 4-5% [14], which is caused by anatomical abnormalities, bleeding, and secretions in the oral and pharyngeal cavities [15,16]. Thus, alternative options for nasotracheal intubation in patients with basal skull defects are needed.…”