Suction catheter as a guide for nasotracheal intubation under general anesthesia: randomized clinical trial of efficacy.

The aim of this study was to evaluate the efficacy of the suction catheter-guided ETT during NTI under general anesthesia. It was hypothesized that suction catheter guided method would reduce the injuries to nasal passage and improve the navigability. The study was designed as a single-site, randomized clinical trial with equal randomization (1:1), double-blinded (participants and primary outcome assessor) and parallel design. The primary outcomes were the incidence and extent of bleeding. Records from the videolaryngoscope (GlideScope®) during intubation were reviewed. Only bleeding observed at posterior pharyngeal area, originating from trauma during the attempt to pass the ETT through the nasal passage, was accounted for. Bleeding was scored at its most severe state observed from the insertion to the removal of the videolaryngoscope after successful intubation, using a 4-point scale: 0 (no bleeding); 1 (blood-stained tube and/or cuff); 2 (blood-stained posterior pharyngeal wall; 3 (blood pooling at the posterior pharyngeal wall). Secondary outcomes included ease of navigation through the nasal passage, first-pass success rate, number of attempts, and nasal passage time. Ease of navigation was graded as follows: smooth (no resistance, no adjustments needed); slight resistance (resistance encountered, requiring manipulation more than once); and impinged (unable to pass through, requiring a change of nostril). The first-pass success rate was defined as the rate of successful nasal pass without changing nostrils. The number of attempts referred to the times the ETT needed to be withdrawn completely in order to find a new angulation, change nostrils or decrease the tube size before successful intubation. Nasal passage time was measured from when the ETT or suction catheter entered the anterior nares until the ETT passed into the pharynx or the suction catheter was completely withdrawn from the ETT.本研究旨在评估全身麻醉下经鼻气管插管（Nasal Tracheal Intubation, NTI）中，吸引导管引导气管导管（Endotracheal Tube, ETT）方法的有效性。研究假设该吸引导管引导法可减轻鼻腔通路损伤，并提升插管操控性。本研究为单中心、1:1均等随机化、双盲（受试者及主要结局评估者设盲）、平行对照的随机临床试验。 主要结局为出血发生率及出血程度。本研究回顾了插管过程中视频喉镜（GlideScope®）记录的影像数据，仅统计经鼻腔通路置入气管导管时所致创伤引发的咽后壁出血。出血评分采用4分制，以成功插管后视频喉镜置入至拔除期间观察到的最严重出血状态进行评定：0分（无出血）；1分（导管及/或套囊染血）；2分（咽后壁染血）；3分（咽后壁血液蓄积）。次要结局包括鼻腔通路操控难度、首次插管成功率、插管尝试次数及鼻腔通路耗时。其中，操控难度分级如下：顺畅（无阻力，无需调整）；轻度阻力（遇阻力，需多次操作）；受阻（无法通过，需更换鼻腔）。首次插管成功率定义为无需更换鼻腔即可成功经鼻置入气管导管的比率。插管尝试次数指成功插管前，需完全拔出气管导管以调整角度、更换鼻腔或减小导管型号的次数。鼻腔通路耗时指从气管导管或吸引导管进入前鼻孔起，至气管导管进入咽部或吸引导管完全从气管导管内撤出为止的时长。