Automated tracheal intubation in an airway manikin using a robotic endoscope: a proof of concept study

Robotic endoscope-automated via laryngeal imaging for tracheal intubation (REALITI) has been developed to enable automated tracheal intubation. This proof-of-concept study using a convenience sample of participants, comprised of trained anaesthetists and lay participants with no medical training, assessed the performance of a robotic device for the insertion of a tracheal tube into a manikin. A prototype robotic endoscope device was inserted into the trachea of an airway manikin by seven anaesthetists and seven participants with no medical training. Each individual performed six device insertions into the trachea in manual mode and six in automated mode. The anaesthetists succeeded with 40/42 (95%) manual insertions (median (IQR [range]) 17 (12–26 [4–132]) s) and 40/42 (95%) automated insertions (15 (13–18 [7–25]) s). The non-trained participants succeeded in 41/42 (98%) manual insertions (median (IQR [range]) 18 (13–21 [8–133]) s) and 42/42 (100%) automated insertions (16 (13–23 [10–58])] s). The duration of insertion did not differ between groups. An effect of increasing experience was observed in both groups in manual mode. A Likert scale for ‘ease of use’ (0 = very difficult to 10 = very easy) showed similar results within the two groups; the mean (SD) was 5.9 (2.1) for the anaesthetists and 6.9 (1.3) for the non-trained participants. We have successfully performed the first automated tracheal device insertion in a manikin with comparable results in a convenience sample of anaesthetists and lay participants with no medical training.     

Evaluation of tracheal intubation in several positions by the Pentax-AWS Airway Scope: a manikin study

Purpose

In emergency situations, rescuers must occasionally secure the airway while the patient is in a restricted position rather than in the ideal supine position. We hypothesized that the Pentax-AWS Airway Scope (AWS) may be useful for emergent tracheal intubation in such positions.

Methods

Thirteen non-anesthesia residents performed tracheal intubation on a simulated manikin in the supine (Supine), left-lateral decubitus (Left-LT), right-lateral decubitus (Right-LT), prone (Prone), and sitting (Sitting) position, respectively, to assess AWS performance.

Results

Intubations were successful in all five positions. The time needed to secure the airway did not differ significantly between the Left-LT and Supine positions. Doctors required significantly more time to secure the airway in the Prone, Sitting, and Right-LT positions than in the Supine position. Visual analog scale (VAS) scoring of the subjective difficulty of laryngoscopy was lower in the Supine position rather than in the Right-LT, Prone, and Sitting positions. The VAS score of subjective difficulty of tracheal tube passage through the glottis was significantly higher in the Sitting position than in the other four positions.

Conclusion

Although tracheal intubations with AWS in all five positions tested were successful, intubation with the patient in the Sitting, Right-LT, and Prone positions was more difficult and required more time than that in the Supine position.     

Evaluation of the new Viewmax laryngoscope in a simulated difficult airway

BACKGROUND: In this study, we evaluated the learning curve and performance of the Viewmax laryngoscope during simulated difficult laryngoscopy in an intubation manikin (Laerdal Airway Management Trainer). METHODS: To determine the learning curve, 25 anaesthesiologists without previous experience with the Viewmax laryngoscope performed 10 successive intubations in an intubation manikin with a normal airway. Time to intubation and failed intubation attempts were recorded. Another manikin was modified to enable comparison of the Viewmax laryngoscope with Macintosh and McCoy laryngoscopes. The time to intubation, number of failed intubation attempts, modified Cormack and Lehane (MCL) laryngeal view grading, percentage of glottic opening (POGO score), use of gum elastic bougie and subjective rating of degree of difficulty were recorded. RESULTS: The learning curve for the Viewmax laryngoscope showed a progressive decrease in time to successful intubation and reached a plateau at the sixth attempt. In simulated difficult laryngoscopy, the Viewmax laryngoscope demonstrated significantly better laryngeal view than the Macintosh and McCoy laryngoscopes in terms of MCL grading (Macintosh, P = 0.01; McCoy, P < 0.01) and POGO score (Macintosh, P < 0.01; McCoy, P < 0.01). The time required for intubation in simulated difficult laryngoscopy for the Viewmax laryngoscope was significantly longer than that for the Macintosh (P = 0.02) and McCoy (P < 0.01) laryngoscopes. There was no significant difference in the degree of difficulty, number of failed intubations and use of gum elastic bougie. CONCLUSION: When compared with the Macintosh and McCoy laryngoscopes in a manikin, the Viewmax laryngoscope appears to improve the view of the larynx but requires a longer time for tracheal intubation.     

Comparison of tracheal intubation by the Macintosh laryngoscope and Pentax-AWS (Airway Scope) during chest compression: a manikin study

To compare tracheal intubation with the Pentax Airway Scope (AWS) and the Macintosh laryngoscope (McL) during chest compression, 25 anesthesiologists (including 12 specialists having >5 years of experience and 13 trainees having <2 years of experience) performed tracheal intubation using either the McL or the AWS, with or without chest compression, on a manikin. Using the McL, both specialists and trainees took a significantly longer time (P < 0.01) to secure the airway with chest compression (17.3 ± 3.7 and 22.5 ± 8.0, respectively) and than without chest compression (11.3 ± 2.9 and 13.9 ± 4.4 s, respectively). No significant difference was observed in time needed to secure the airway using the AWS with or without chest compression in both groups. From the standpoint of experience, time to complete intubation for specialists using the McL during chest compression was significantly shorter than that for trainees. In contrast, the difference in time to complete intubation with the AWS during chest compression was not significantly different between the two groups. Based on these results, we conclude that the use of the AWS may reduce the time needed to secure the airway during chest compression.     

Anesthesia of a patient with an obstructing tracheal mass: a new way to manage the airway

A case of upper airway obstruction due to thyroid tumor requiring surgery is presented. Successful establishment of an open tracheal airway was achieved by the insertion of an endotracheal stent and was followed 10 days later by tracheal resection and anastomosis.     

可视喉镜在新生儿手术气管插管中的应用

目的探讨可视喉镜在新生儿手术气管插管中的应用。方法选择2013-07—2013-12间行新生儿手术50例为研究对象,随机分为可视喉镜组(A组)25例和直接喉镜组(B组)25例,比较两组新生儿气管插管时声门暴露时间,完成气管插管的时间,插管一次成功率和新生儿插管前3 min、插管时及插管后3 min的平均动脉压(MAP)、心率(HR)的变化及插管相关不良反应。结果 A组与B组相比,A组声门暴露时间,完成气管插管的时间均明显缩短,A组插管一次成功率96%,B组插管一次成功率80%,差异有统计学意义。两组新生儿插管前和插管后3 min的MAP和HR比较,差异无统计学意义。但与B组相比,插管时A组新生儿MAP和HR明显降低,差异有统计学意义。A组新生儿插管时不良反应明显低于B组,差异有统计学意义。结论可视喉镜可提高新生儿手术气管插管时成功率,缩短声门暴露时间,气管插管的时间,降低插管不良反应,提高新生儿手术麻醉安全性。     

Difficult Airway Society guidelines for awake tracheal intubation (ATI) in adults

Awake tracheal intubation has a high success rate and a favourable safety profile but is underused in cases of anticipated difficult airway management. These guidelines are a comprehensive document to support decision making, preparation and practical performance of awake tracheal intubation. We performed a systematic review of the literature seeking all of the available evidence for each element of awake tracheal intubation in order to make recommendations. In the absence of high-quality evidence, expert consensus and a Delphi study were used to formulate recommendations. We highlight key areas of awake tracheal intubation in which specific recommendations were made, which included: indications; procedural setup; checklists; oxygenation; airway topicalisation; sedation; verification of tracheal tube position; complications; management of unsuccessful awake tracheal intubation; post-tracheal intubation management; consent; and training. We recognise that there are a range of techniques and regimens that may be effective and one such example technique is included. Breaking down the key practical elements of awake tracheal intubation into sedation, topicalisation, oxygenation and performance might help practitioners to plan, perform and address complications. These guidelines aim to support clinical practice and help lower the threshold for performing awake tracheal intubation when indicated.     

Airway lesions caused by prolonged intubation with standard and with anatomically shaped tracheal tubes. A post-mortem study

Two groups of patients intubated for long periods were examined post mortem. In Group A (22 patients) the mean duration of intubation was 4.0 days and in Group B (19 patients) 5.7 days. The mean for the two groups was 4.8 days. In Group A a conventional endotracheal tube was used, and in Group B an anatomically shaped tube. Both tubes had cuffs of the intermediate-volume, low-pressure type. The larynx and trachea, from the epiglottis to the bifurcation, were removed in one piece at autopsy and the inner surface was photographed. The photographs were magnified and from these the size and estimated depth of any lesions were recorded. In the arytenoid and tracheal regions no significant difference was found between the two groups. In the cricoid region, on the other hand, the outcome was significantly more favourable following use of the anatomically shaped tube.     

视频喉镜引导困难气管插管的护理配合

对69例气管插管困难患者在视频喉镜引导下气管插管成功,无一例因护理配合不当出现并发症。提出术前做好用物准备,对患者气管插管困难进行预测及判断患者有无寰椎关节运动受限或张口异常,针对性做好应对措施;术中熟练操作步骤,密切配合,加强生命体征观察,可提高气管插管成功率、减少损伤、增加安全性。     

Comparison of the Airway Scope, gum elastic bougie and fibreoptic bronchoscope in simulated difficult tracheal intubation: a manikin study

We compared the Airway Scope with a gum elastic bougie and fibreoptic bronchoscope in a manikin with a simulated Cormack and Lehane Grade 3 laryngoscopic view. Twenty-seven anaesthetists intubated the trachea of the manikin with these devices and the time required for intubation was measured. They were then asked to rate the subjective difficulty of intubation (1 = very easy; 5 = very difficult). Mean (SD) intubation times were 16.6 (11.2) s with the Airway Scope, 29.4 (10.9) s with the gum elastic bougie (p < 0.0001), and 30.6 (20.0) s with the fibreoptic bronchoscope (p < 0.0001). The median (range) difficulty was 2 (1-4) with the Airway Scope, 3 (2-4) with the gum elastic bougie (p < 0.001), and 2 (1-5) with the fibreoptic bronchoscope (p = 0.014). In Cormack and Lehane grade 3 laryngoscopic views, the Airway Scope may enable faster and easier tracheal intubation than does a Macintosh laryngoscope with a gum elastic bougie or a fibreoptic bronchoscope.     

Comparison of a new video-optical intubation stylet versus the conventional malleable stylet in simulated difficult tracheal intubation

Handling and efficacy of a new video-optical intubation stylet were assessed in a simulated difficult tracheal intubation setting and compared with a conventional malleable stylet. Forty-five anaesthetists performed 10 tracheal intubations using both techniques. Laryngoscopy was performed by the observer, who created a grade 3 view according the classification by Cormack and Lehane. The time taken to place the tracheal tube and the final tracheal tube positions were documented. Mean (SD) intubation time for the video-optical stylet was 20.4 (7.7) s and for the malleable stylet 10.2 (3.3) s (p<0.01). With the video-optical stylet the trachea was correctly intubated in all 225 attempts; with the malleable stylet 44 (19.6%) oesophageal and 44 (19.6%) endobronchial intubations occurred (p<0.01). The video-optical intubation stylet enabled us to recognise inappropriate tracheal tube positions and to correct them immediately. This equipment can be considered a reliable and effective tool for management of the difficult airway.     

The rigid nasendoscope as a tool for difficult tracheal intubation: a manikin study

We examined the use of the 30 degrees rigid nasendoscope in aiding difficult tracheal intubations. A Cormack and Lehane grade 4 difficult intubation (no view of glottis or epiglottis) was set up on a manikin. After 10 s of tuition, 40 anaesthetists attempted to pass a standard gum elastic bougie between the cords, with and without the nasendoscope, in randomised order. A bougie curved to an 'optimal curve' was also tested. Using the standard bougie 13/40 (33%) passed the bougie between the cords without the nasendoscope, compared with 31/40 (78%) when using the nasendoscope (p < 0.001). The 'optimal curve' bougie resulted in 29/40 (73%) and 39/40 (98%) success rates without and with the nasendoscope, respectively (p = 0.004). The nasendoscope is a simple and easy to use tool in grade 4 intubation, and results are improved further by the use of an 'optimal curve' bougie.     

First clinical experience of tracheal intubation with the SensaScope, a novel steerable semirigid video stylet

Background. Problems with tracheal intubation are a major causeof anaesthesia-related morbidity and mortality. Difficulty withtracheal intubation is primarily a consequence of failure tosee the vocal cords with conventional direct laryngoscopy. Wereport our experience with use of the SensaScope^® for trachealintubation in routine clinical practice. Methods. The SensaScope^® is a hybrid steerable semirigidS-shaped video stylet. Its handling and performance were assessedby anaesthetists with a minimum of 1 yr of experience. Theyperformed four intubations each with the device in anaesthetizedelective surgical patients. The view of the glottis with theMacintosh laryngoscope was compared with the view shown on themonitor by the SensaScope^®. The time taken to complete intubation,the final tracheal tube (TT) position and the degree of difficultyof the procedure were recorded. Results. Thirty-two patients were studied. All Macintosh Cormackand Lehane grade 3 patients were converted to grade 1 or 2 withthe SensaScope^®. Mean intubation time was 25 (12) s andcorrect mid-tracheal TT cuff position was achieved in all cases.The degree of difficulty was 3.0 (1.8) on a numerical scaleranging from 0 to 10. All operators rapidly became familiarwith the device and mastered its technique of use. Conclusion. The SensaScope^® is a reliable and effectivedevice for tracheal intubation under vision of the normal airway.It has great potential to facilitate management of difficultairway situations in anaesthetized and paralysed patients.     

Tosight视频喉镜在Klippel-Feil综合征患儿气管插管中的应用

目的探讨Tosight视频喉镜在Klippel-Feil综合征(KFS)患儿气管插管中的应用效果。方法 20例KFS患儿,年龄4~12岁,ASAⅡ或Ⅲ级,随机均分为两组:Tosight可视喉镜组(T组)和Macintosh喉镜组(M组)。记录喉镜下喉部显露分级(Cormack-Lehane分级)、气管插管时间、气管插管次数、插管成功率和并发症发生情况。结果 T组全部完成气管插管,M组完成6例气管插管。T组气管插管时间明显短于、插管次数明显少于M组(P0.05)。两组患儿均无严重并发症发生。结论 Tosight视频喉镜用于KFS患儿气管插管操作简单,声门暴露清晰,插管成功率高,插管时间短,优于Macintosh喉镜。     

A comparison of the Trachway intubating stylet and the Macintosh laryngoscope in tracheal intubation: a manikin study

Purpose

The Trachway intubating stylet (Trachway^®), when used by experienced anesthesiologists, has been shown to be effective for difficult airway management. We evaluated the efficacy of this intubating stylet for tracheal intubation in a manikin when used by experienced laryngoscopists with little experience using this device.

Methods

Thirty-eight nurse anesthesiologists intubated the trachea of a manikin (Laerdal Airway Management Trainer) with a Trachway intubating stylet or a Macintosh laryngoscope in easy and difficult laryngoscopy scenarios. The duration of the intubation attempts, success rates, dental trauma, and ease of use (0 = very easy; 10 = very difficult) were recorded. The primary endpoint was the duration of the successful tracheal intubation attempt in the difficult laryngoscopy scenario. Data are presented as means (SD).

Results

Both devices resulted in similar tracheal intubation performance in the easy laryngoscopy scenario. However, the Trachway intubating stylet provided shorter intubation times (20.8 ± 5.6 vs. 25.5 ± 7.3 s; p = 0.003) and easier intubations (2.4 ± 1.6 vs. 5.7 ± 1.8; p < 0.001) compared with the Macintosh laryngoscope in the difficult laryngoscopy scenario. All tracheal intubations were successful and no dental trauma was observed when using the Trachway intubating stylet.

Conclusion

We concluded that the Trachway intubating stylet, when used by novices, is effective in both easy and difficult laryngoscopy scenarios. In difficult laryngoscopy scenarios, this device provided faster, easier, and less traumatic intubation than the Macintosh laryngoscope.