Trachway in assistance of nasotracheal intubation with a preformed nasotracheal tube in patients undergoing oral maxillofacial surgery

Abstract

Editor—The advantages of Trachway over cuff-supplement Macintosh laryngoscope for nasotracheal intubation (NTI) have been shown by measurement of intubation time spent, scores of modified nasotracheal intubation difficulty scales (MNIDS), intubation-related side-effects, and complications. From December 2012 to August 2013, we studied 100 patients undergoing oro-maxillofacial surgery with NTI (KMUH-IRB-20120320 and ClinicalTrials.gov Identifier: NCT01917409). Patients with potential difficult airway were excluded. Cocaine 4% 1 ml was sprayed into the nostril by an atomization device (MAFgic™, UT, USA). Induction agents were administered in the following order: fentanyl 2 μg kg−1, thiamylal 5 mg kg−1, rocuronium 0.6 mg kg−1, and propofol 1 mg kg−1. A preformed double-curve nasotracheal tube (RAE Nasal, Athlone, Ireland) was provided; for men, 7.0 mm inner diameter (ID) and for women, 6.5 mm ID. In the laryngoscope group, a Macintosh no. 3 standard curved blade was used. Two attempts of tube advancement from the nasopharynx space to trachea were allowed and then supplements with 15 ml air cuff inflation or a backward, upward, right-sided pressure (BURP) manoeuvre were used to assist intubation. In the Trachway group (n=50), a malleable video stylet (Trachway, Tai-Chung, Taiwan), which was 42.5 cm long, 0.5 cm in diameter with anterior bending length 10 cm, and bending angle 70°, was loaded into the nasotracheal tube as a Trachway-tube assembly and stylet tip left behind the Murphy eye. The total intubation time was summed up by Time 1 (T1, from removal of the face mask to tube tip in the nasopharynx), Time 2 (T2, from using tools either laryngoscope or handling Trachway to advancing the tube into the trachea), and Time 3 (T3, from removal of tools to appearance of a series of three plateau E CO2′ waveforms). Epistaxis was assessed anteriorly by nostril bleeding and posteriorly by grading of blood in the oropharynx (0, none; 1, minimal; 2, slight; 3, moderate; 4, severe). MNIDS scored intubation conditions were assessed as follows: N1, additional intubation attempts; N2, number of supplementary operators, directly but not assisted; N3, alternative intubation techniques such as change of head position, cuff inflation, or Magill forceps intervention; N4, glottic exposure grading as Cormack–Lehane1Cormack RS Lehane J Difficult tracheal intubation in obstetrics.Anaesthesia. 1984; 39: 1105-1111Crossref PubMed Scopus (1946) Google Scholar minus 1; N5, lifting force; N6, glottic exposure with BURP manoeuvre; N7, vocal cords position. The MNIDS scores were categorized as easy (0), minor difficulty (0<scores≤5), major difficulty (5<scores), and impossible intubation or failed intubation (scores=∞).2Adnet F Borron SW Racine SX et al.The intubation difficulty scale (IDS): proposal and evaluation of a new score characterizing the complexity of endotracheal intubation.Anesthesiology. 1997; 87: 1290-1297Crossref PubMed Scopus (481) Google Scholar There were no statistical differences between the groups on patient characteristic data, haemodynamic responses to intubation, and side-effects. One patient unexpectedly failed intubation and one tube advancement into retropharyngeal mucosa in the laryngoscope group were excluded from the final analysis. The total intubation time and T2 time spent were significantly shorter in the Trachway group (Table 1). In the laryngoscope group, six patients were considered as major difficulty in intubation. The median score of MNIDS was three in the laryngoscope group and zero in the Trachway group. Some patients in the laryngoscope group needed cuff inflation or BURP manoeuvre during intubation, but none in the Trachway group.Table 1.Intubation-related data including of attempts, intubation time intervals, MNIDS scores, and intubation auxiliary tools used. Time intervals values are shown as mean (sd) *Values shown as median with 95% confidence interval.Laryngoscope (n=50)Trachway (n=50)P-valueIntubation attempts 135 (70%)50 (100%)<0.001 213 (26%)0 (0%) Failed2 (4%)0 (0%)MNIDS score*3.0 (2.21–3.50)0.00 (0.0–0.30) IDS score =011 (22%)50 (100%)<0.001 IDS score 1–531 (62%)0 (0%) IDS score >56 (12%)*0 (0%) IDS score ∞2 (4%)0 (0%)Time interval (s)Laryngoscope (n=48)Trachway (n=50) T18.17 (6.11)6.78 (1.52)0.124 T229.6 (11.34)12.62 (4.72)<0.001 T314.15 (2.92)12.86 (2.93)0.32 Total time (Tt)51.92 (14.13)32.26 (5.24)<0.001Inflate cuff No/yes31 (62%)/17 (38%)50 (100%)/0 (0%)<0.001BURP manoeuvre No/yes21 (46%)/27 (54%)50 (100%)/0 (0%)<0.001Nostril bleeding No/yes48/050/0Blood in oropharynx No/yes18 (37.5%)/30 (62.5%)29 (58%)/21 (42%)0.042 Open table in a new tab In this study, the Trachway-tube assembly provided a smooth advancement from selected nostril through the nasopharynx into trachea and needed no opening of the patient's mouth. By using the Macintosh laryngoscope, the mean total intubation time spent took nearly 2 min for trainees3Hirabayashi Y GlideScope videolaryngoscope facilitates nasotracheal intubation.Can J Anaesth. 2006; 53: 1163-1164Crossref PubMed Google Scholar and around 1 min for experienced intubators with Magill forceps.4Jones PM Armstrong KP Armstrong PM et al.A comparison of glidescope videolaryngoscopy to direct laryngoscopy for nasotracheal intubation.Anesth Analg. 2008; 107: 144-148Crossref PubMed Scopus (97) Google Scholar This is in line with our findings. In the Trachway group, however, a mean total intubation time was 32.3 s along with easy intubation conditions. Using the Trachway technique to establish a nasal airway with a preformed double-curved nasotracheal tube is feasible and an efficient technique. None declared.