Karki Sauharda Bikram, Kale Suniti, Saigal Deepti
Department of Anaesthesiology and Critical Care, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India.
Anesth Essays Res. 2022 Jan-Mar;16(1):115-120. doi: 10.4103/aer.aer_36_22. Epub 2022 Jun 29.
The application of manual in-line stabilization (MILS) for minimizing spinal cord injury is known to increase difficulty in airway management.
The study aims to assess the change in Modified Cormack-Lehane (CL) laryngoscopic view with the application of MILS from the early morning sniffing position (EMSP) in adult patients.
This was a prospective, interventional, self-controlled study conducted on 220 patients aged 18-65 years, belonging to the American Society of Anesthesiologists Physical Status Class I or II, having a normal airway, and scheduled for elective surgery under general anesthesia.
After inducing general anesthesia, MILS was applied to the patient's neck, and a Modified CL view of the vocal cords was recorded under direct laryngoscopy. The view was again noted after applying backward-upward-rightward pressure (BURP). MILS and BURP were released. The view was obtained again with and without BURP in EMSP.
Normality of data was tested by Kolmogorov-Smirnov test. Wilcoxon ranked-sum test for quantitative variables and Chi-square test for qualitative variables were used.
On application of MILS, the majority of patients had Modified CL Grade 3a (121 patients) and 3b (53 patients) views. The majority of patients had Modified CL Grade 1 (114 patients) and 2a (71 patients) views on placing in EMSP. These findings were statistically significant ( < 0.0001). Consequent to the placement of BURP upon MILS, patients with lower CL Grade views (2b: 101 patients) were significantly higher ( < 0.0001) in comparison with MILS alone.
In patients with a normal airway, MILS leads to a significantly greater incidence of higher grades of laryngoscopic views in comparison to EMSP. Use of BURP after MILS causes significantly less incidence of higher grades of laryngoscopic view when compared with MILS alone. All patients requiring MILS should be considered to be a difficult airway, and hence, preparation should be done accordingly.
已知应用手动在线稳定（MILS）以尽量减少脊髓损伤会增加气道管理的难度。
本研究旨在评估成年患者从清晨嗅物位（EMSP）应用MILS后改良Cormack-Lehane（CL）喉镜视野的变化。
这是一项前瞻性、干预性、自身对照研究，对220例年龄在18 - 65岁之间、属于美国麻醉医师协会身体状况分级I或II级、气道正常且计划在全身麻醉下进行择期手术的患者进行。
诱导全身麻醉后，对患者颈部应用MILS，并在直接喉镜检查下记录声带的改良CL视野。在施加向后 - 向上 - 向右压力（BURP）后再次记录视野。释放MILS和BURP。在EMSP下有和没有BURP的情况下再次获取视野。
数据的正态性通过Kolmogorov-Smirnov检验进行测试。使用Wilcoxon秩和检验分析定量变量，使用卡方检验分析定性变量。
应用MILS时，大多数患者的改良CL分级为3a（121例患者）和3b（53例患者）视野。置于EMSP时，大多数患者的改良CL分级为1级（114例患者）和2a级（71例患者）视野。这些发现具有统计学意义（<0.0001）。在MILS基础上施加BURP后，与单独使用MILS相比，CL分级较低视野（2b：101例患者）的患者显著增多（<0.0001）。
在气道正常的患者中，与EMSP相比，MILS导致更高等级喉镜视野的发生率显著更高。与单独使用MILS相比，MILS后使用BURP导致更高等级喉镜视野的发生率显著降低。所有需要MILS的患者都应被视为困难气道，因此应相应做好准备。
