Pentax-AWS Airwayscope Research Articles

Manual laryngeal fixation facilitates tracheal intubation during chest compression: A randomized crossover manikin study

PurposeWe compared the effectiveness of external manual laryngeal fixation (MLF) for tracheal intubation during chest compression using three laryngoscopes, the Macintosh laryngoscope (McL), McGRATH® MAC (McGRGTH), and Pentax-AWS Airwayscope® (AWS) on an adult manikin. MethodsSixteen novice doctors and 15 experienced anesthesiologists performed tracheal intubation during chest compression on an adult manikin using the McL, McGRATH, and AWS with or without MLF. Tracheal intubation time and intubation success rate were measured. ResultsIn the AWS trial, all novice and experienced doctors successfully secured the airway with or without MLF during chest compression. In McL and McGRATH trials, MLF significantly improved the rate of successful intubation during chest compression compared to without MLF for novice doctors. While intubation time did not significantly differ with or without MLF in the AWS trial, MLF significantly shortened intubation time in McL and McGRATH trials for both novice and experienced doctors. ConclusionThese findings suggest that MLF facilitates tracheal intubation with the McL and McGRATH during chest compression.

Evaluation of gum-elastic bougie combined with direct and indirect laryngoscopes in vomitus setting: A randomized simulation trial

PurposeVideolaryngoscopes may not be useful in the presence of vomitus due to blurred images on the monitor. The objective of our study is to compare the utility of gum-elastic bougie (GEB) application for tracheal intubation with the Macintosh laryngoscope (McL), which is a direct laryngoscope, with that of the Pentax-AWS Airwayscope® (AWS) and McGRATH® MAC (McGRATH) in simulated vomitus settings. MethodsSixteen novice doctors performed tracheal intubation on an adult manikin using McL, AWS, and McGRATH with or without GEB under normal and vomitus simulations. ResultsIn the normal setting the tracheal intubation was successful with the three laryngoscopes regardless of GEB application. In the vomitus setting, the intubation success rate did not significantly improve using McL, while it did using McGRATH or AWS. In the normal settings, GEB application significantly lengthened the intubation time in all three laryngoscopes. By contrast, in the vomitus settings, GEB application significantly shortened the intubation time in all three laryngoscopes. For the comparison of three laryngoscopes, the intubation time did not differ significantly in normal setting, while it was significantly longer in McG and AWS trials than McL trial. ConclusionThe GEB application facilitates the tracheal intubation in the vomitus setting using McGRATH and AWS in adult simulation.

Comparison of cricoid pressure effect between McGRATH® MAC and Pentax-AWS Airwayscope®: A prospective randomized trials

Comparison of cricoid pressure effect between McGRATH® MAC and Pentax-AWS Airwayscope®: A prospective randomized trials

Abstract PR538

Background & Objectives: The appropriate pillow height for tracheal intubation with the Pentax-AWS Airwayscope® (AWS) has not been assessed. This randomised clinical trial aimed to compare pillow height for tracheal intubation with the AWS in patients undergoing elective surgery. Materials & Methods: This study was listed in the UMIN Clinical Trials Registry under registration number UMIN000018208. After obtaining approval from the Research Ethics Committee, 90 patients were assessed for study eligibility from September 2015 to January 2016. Of 90 patients, four refused to participate and six were excluded in accordance with eligibility criteria. 80 patients aged 20 to 85 years who were scheduled to undergo general anesthesia in the supine position were randomly assigned to one of two groups: intubation with a high pillow (HP group, 12-cm pillow height; 40 patients) or low pillow (LP group, 4-cm pillow height; 40 patients). Anesthesia was induced with propofol and remifentanil. Intubation time, number of attempts required for Intlock insertion and tracheal tube progression through the glottis, percentage of glottis opening, subjective difficulty of laryngoscopy and tube passage through the glottis using a visual analogue scale (VAS), and postoperative hoarseness and pharyngeal pain were assessed. P<0.05 was considered significant. Results: Intubation time was significantly shorter in the LP group than in the HP group (LP group: 27.9±12.3 s vs. HP group: 46.2±15.0 s; P<0.001). The number of Intlock insertions, Cormack classifications, and POGO scores did not differ between groups (P=0.14, P=0.69, P=0.38, respectively). The number of attempts for tracheal tube progression to the glottis was significantly smaller in the LP group than in the HP group (P=0.003). VAS scores for laryngoscopy and tube passage through the glottis were significantly smaller in the LP group than in the HP group (P=0.001 and P<0.001). Conclusion: Low pillow height facilitates tracheal intubation with the AWS by reducing intubation time, smoothing tracheal tube progression through the glottis, and diminishing postoperative hoarseness in anesthetised patients. Disclosure of Interest: None declared

Cricoid Pressure Impedes Tracheal Intubation With the Pentax-AWS Airwayscope®

Abstract Background It is unclear how cricoid pressure affects tracheal intubation with the Pentax-AWS Airwayscope® (AWS). We conducted a prospective randomized clinical trial in anaesthetized patients. Methods Sixty patients were allocated to either the cricoid pressure (CP) group (n+30) or the sham group (n+30). We compared the two groups with regard to intubation time, number of attempts required for insertion of the Intlock blade (disposable blade of the AWS) and tracheal intubation, percentage of glottic opening (POGO) score, and subjective difficulty of both laryngoscopy and passage of a tube through the glottis. Results Intubation time was significantly longer in the CP group (median 45[IQR40–59] s) than in the sham group (32[28–45] s) (P+0.003, 95% CI for median difference 5–24 s). The number required for insertion of the Intlock blade did not differ between the groups (P+0.08), but the number for tracheal intubation was significantly higher in the CP group (1 attempt in 14 patients, 2 in 7, 3 in 9) than in the sham group (1 attempt in 24 patients, 2 in 6; P+0.002). POGO score did not differ significantly between the groups (P+0.60), nor did the subjective difficulty of laryngoscopy (P+0.06). The visual analogue scale score for passage of a tube through the glottis was significantly higher in the CP group than in the sham group (P Conclusions Cricoid pressure impedes tracheal intubation using the AWS, and is associated with longer intubation time, which can be attributed to increased difficulty in the passage of a tube through the glottis. Clinical Trial registry number UMI18209.

Cricoid pressure impedes tracheal intubation with the Pentax-AWS Airwayscope®: a prospective randomized trial

BackgroundIt is unclear how cricoid pressure affects tracheal intubation with the Pentax-AWS Airwayscope® (AWS). We conducted a prospective randomized clinical trial in anaesthetized patients. MethodsSixty patients were allocated to either the cricoid pressure (CP) group (n+30) or the sham group (n+30). We compared the two groups with regard to intubation time, number of attempts required for insertion of the Intlock blade (disposable blade of the AWS) and tracheal intubation, percentage of glottic opening (POGO) score, and subjective difficulty of both laryngoscopy and passage of a tube through the glottis. ResultsIntubation time was significantly longer in the CP group (median 45[IQR40–59] s) than in the sham group (32[28–45] s) (P+0.003, 95% CI for median difference 5–24 s). The number required for insertion of the Intlock blade did not differ between the groups (P+0.08), but the number for tracheal intubation was significantly higher in the CP group (1 attempt in 14 patients, 2 in 7, 3 in 9) than in the sham group (1 attempt in 24 patients, 2 in 6; P+0.002). POGO score did not differ significantly between the groups (P+0.60), nor did the subjective difficulty of laryngoscopy (P+0.06). The visual analogue scale score for passage of a tube through the glottis was significantly higher in the CP group than in the sham group (P<0.001). ConclusionsCricoid pressure impedes tracheal intubation using the AWS, and is associated with longer intubation time, which can be attributed to increased difficulty in the passage of a tube through the glottis. Clinical Trial registry numberUMIN000018209.

A successful case of pediatric tracheal tube exchange utilizing gum-elastic bougie and videolaryngoscope.

Here we report on our experiences with successful pediatric tracheal tube exchange utilizing the gum-elastic bougie (GEB; SmithMedical, USA) and videolaryngoscope (Pentax-AWS Airwayscope®; Hoya, Japan) with an infant-size Intlock in a ventilated child, whose condition was complicated by pneumonia and dilated cardiomyopathy. A 2-year-old female (height 77 cm; weight 8.8 kg) was transferred to our emergency department due to severe dyspnea and vital sign collapse. She was diagnosed with cardiac failure due to dilated cardiomyopathy associated with pneumonia. We performed emergent tracheal intubation with a tracheal tube with an internal diameter (ID) of 3.5 mm, and sedated her with midazolam and dexmedetomidine. Intensive care was continued with antibiotics and mechanical ventilation, and catecholamine support with dobutamine was added. Demands for secretion management and ventilator weaning dictated tracheal tube exchange with a larger size tube. To avoid cardiopulmonary collapse associated with tube exchange or prolonged hypoxia, we decided to perform tracheal tube exchange with

Influence of clinical experience of the Macintosh laryngoscope on performance with the Pentax-AWS Airway Scope(®), a rigid video-laryngoscope, by paramedics in Japan.

We sought to establish the clinical utility of the Pentax-AWS Airway Scope(®) (AWS) when used by paramedics to intubate the trachea, and to evaluate whether their performance was influenced by previous clinical experience with the Macintosh laryngoscope (ML). Twenty paramedics attempted tracheal intubation using the AWS in five patients each in the operating room. We recorded the success rate, the number of intubation attempts, and the time for intubation and adverse events, and compared these based on the paramedics' previous clinical experience with the ML. Ten paramedics had no prior clinical experience of the ML (group A) and 10 had used it on more than 30 occasions (group B). The intubation success rate was 99 % (99/100). Notably, 96 % (47/49) of intubations were achieved on the first attempt by the inexperienced paramedics in group A, compared with 64 % (32/50) by the experienced paramedics in group B (p = 0.0001). The time to intubation (mean ± SD) was significantly shorter in group A than in group B (37 ± 24 vs. 48 ± 21 s, p = 0.002). There were marked variations in the times taken to intubate, but no apparent improvement as the intubators gained experience between their first and fifth cases. No complications were encountered in either group. We found that paramedics could achieve a high tracheal intubation success rate using the AWS independent of previous airway management experience. Better intubation performance with the AWS was observed in paramedics without clinical experience with the ML.

Comparison of tube-guided and guideless videolaryngoscope for tracheal intubation during chest compression in a manikin: a randomized crossover trial

Previous studies have shown the utility of indirect glottis viewing videolaryngoscopes for tracheal intubation during chest compression, but the efficacy of a videolaryngoscope with tube guide has not been sufficiently validated. We compared the utility of two videolaryngoscopes, the KingVISION(®) (KingV) with or without tube guide blade and Pentax-AWS Airwayscope(®) (AWS), which contain tube guide function, during chest compressions on an adult manikin. Twenty-five novice doctors and 22 experienced anesthesiologists performed tracheal intubation on an adult manikin using the AWS and KingV with or without chest compressions. The KingV trials were performed either with a tube guide 'channeled blade' (KingV-Guided) or without, using a 'standard blade' (KingV-Guideless). In the KingV-Guideless trial, all novice doctors successfully secured the airway without chest compressions but seven failed with chest compressions (p < 0.05), while no experienced doctors failed without chest compression and two did during chest compression. In the AWS and KingV-Guided trials, all participants succeeded both with and without chest compressions performed by both novice doctors and experienced anesthesiologists. Intubation time was lengthened significantly by chest compressions in the KingV-Guideless trial (p < 0.05), but not in the AWS or KingV-Guided trials performed by both novice doctors and experienced anesthesiologists. The intubation time for KingV-Guided during chest compression was significantly smaller by experienced anesthesiologists compared to by novice doctors. These findings suggest that the AWS and KingV-Guided devices are more effective than the KingV-Guideless for airway management with chest compressions in adult simulations, especially performed by novice doctors. The tube guide function may contribute to successful airway management during chest compression by the added videolaryngoscopy function.

A comparison of the force applied on oral structures during intubation attempts between the Pentax-AWS airwayscope and the Macintosh laryngoscope: a high-fidelity simulator-based study

ObjectiveWe sought to determine whether the use of Pentax-AWS Airwayscope (AWS) applied less force on oral structures during intubation attempts than a conventional direct laryngoscope (DL).DesignProspective cross-over study.ParticipantsA total of...

Is Airwayscope more effective than Macintosh laryngoscope?

To the Editor: In a manikin study comparing the Pentax-AWS Airwayscope (AWS) and the Macintosh laryngoscope (MLS) during chest compressions, Kohama et al. [1] showed that the AWS was superior to the MLS. Also, they reported the same results in previous manikin studies simulating chest compressions. However, their results are not supported by a randomized controlled trial in prehospital patients primarily with cardiac arrest, in which the AWS was inferior to the MLS in intubation time, success rate, and difficulty of intubation [2]. In this clinical study, an important cause of failed intubation with AWS on the first attempt is oral contamination, which occurs in 45 of 109 patients. When the AWS lens is obscured by contamination, it needs to be removed and cleaned. Obviously, this requires extra time and affects intubation time and success rate. During intubation with MLS, however, use of a suction device to clean oral contamination is easy, and the MLS does not need to be removed to clean the contamination. Actually, vomitus or secretions cannot be modeled by simple or even sophisticated manikins. Rai and Popat [3] have pointed out that manikin studies often reveal results that are impossible to interpret or are even contradictory to subsequent human studies. Thus, we wish to echo Behringer and Kristensen [4] that manikin studies are of negligible value as sole predictor of any given airway device’s value in the clinical setting.

In reply: Is Airwayscope more effective than Macintosh laryngoscope?

To the Editor: We thank Dr. Xue and colleagues [1] for interest in our manuscript. They claim that the utility of the Pentax-AWS Airwayscope (AWS) in our simulation was not clinically validated, which is inaccurate for the following reasons. We performed our study in ‘in-hospital’ cardiac arrest simulation, which is apparently different from other ‘outof-hospital’ clinical trials that they cite. In fact, a previous clinical randomized trial conducted in the emergency ward ‘in-hospital’ setting demonstrated the superiority of the AWS [2]. There are several differences between ‘in-hospital’ and ‘out-of hospital’ CPR in clinical setting, resuscitation equipment, training of rescuers, and environmental factors. There are several aspects of the video laryngoscope that warrant improvements for outdoor usage such as in darkness or fog, and future simulations and clinical studies should address these problems [3]. As we describe in the manuscript, a simulation study utilizing a manikin has some limitations. Further clinical studies leading to meta-analysis may clarify the utility of video laryngoscopes in several situations during resuscitation.

Utility of the Pentax-AWS Airwayscope and Macintosh laryngoscope for airway management during chest compressions in 27° left-lateral tilt: a manikin simulation study of maternal cardiopulmonary resuscitation

American Heart Association (AHA) 2010 cardiopulmonary resuscitation guidelines recommend high-quality chest compressions (minimum interruption, a pace >100 compressions/min, and a depth more than 5 cm). They propose minor changes for pregnant women: manual left deviation of the uterus or a left-lateral incline of 27°-30° to alleviate pressure on the inferior vena cava. We examined the performance of the Pentax-AWS Airwayscope (AWS) and Macintosh laryngoscope (McL) for airway management during chest compressions on a 27° left-lateral tilt (27 LLT) operating table. The study included 18 novice doctors in our anesthesia department. They performed tracheal intubation on a manikin positioned on a 27 LLT operating table using the AWS or McL with or without chest compressions. We measured the intubation time and success rate for tracheal intubation. Intubation success rate with the McL decreased with chest compressions compared to without chest compressions (12/18 vs. 18/18, P < 0.05). Intubation time with the McL was lengthened with chest compressions compared to without chest compressions (18.9 ± 4.0 s vs. 11.1 ± 1.0 s, P < 0.05). Intubation success rate was the same for the AWS with and without chest compressions (18/18 in both cases), and intubation time did not increase significantly without compressions compared to with compressions (11.6 ± 1.4 s vs. 12.6 ± 1.2 s, NS). The AWS is an effective tool for airway management during chest compressions in 27 LLT in a manikin, suggesting that the AWS may be a useful device for airway management during maternal resuscitation.

Comparison of Pentax-AWS Airwayscope, Airtraq and Miller laryngoscope for tracheal intubation by novice doctors during infant cardiopulmonary resuscitation simulation: a randomized crossover trial

Recent guidelines for infant cardiopulmonary resuscitation emphasize that all rescuers should minimize interruption of chest compressions, even for endotracheal intubation. We compared the utility of the Pentax-AWS Airway Scope (AWS) with an infant-sized Intlock (AWS-I), Airtraq laryngoscope (ATQ) and Miller laryngoscope during chest compressions on an infant manikin. Twenty-three novice doctors performed tracheal intubation on an infant manikin using the AWS-I, ATQ and Miller laryngoscope, with or without chest compressions. In Miller laryngoscope trials, one participant failed to secure the airway without chest compressions, while nine failed with compressions (P < 0.05). In ATQ trials, none of the participants failed without compressions, while six failed with compressions (P < 0.05). In AWS-I trials, all participants succeeded regardless of chest compressions. Intubation time was significantly longer with chest compressions with the Miller laryngoscope and ATQ, but not with the AWS-I. The AWS-I is an effective device for endotracheal intubation during chest compressions in infant simulations managed by novice doctors.

AHA-ACLS2010年版ガイドラインにおける気道管理と間接声門視認型喉頭鏡エアウェイスコープの可能性

AHA-ACLS2010年版ガイドラインにおける気道管理と間接声門視認型喉頭鏡エアウェイスコープの可能性

Comparison of the Pentax-AWS Airway Scope with the Macintosh laryngoscope for nasotracheal intubation: a randomized, prospective study

Study ObjectiveTo evaluate the effectiveness of the Pentax-AWS Airway Scope (AWS) in comparison to the Macintosh laryngoscope during nasotracheal intubation. DesignProspective randomized study. SettingOperating room of a university-affiliated hospital. Patients90 ASA physical status 1 and 2 adults, aged 18 to 72 years, scheduled for orthodontia surgery requiring nasotracheal intubation. InterventionsPatients were randomly assigned to three groups to undergo tracheal intubation with a Macintosh laryngoscope (Group Mac; n = 30), AWS with its tip inserted into the vallecula for indirect elevation of the epiglottis (Group AWS-I; n = 30), or AWS with its tip positioned posterior to the epiglottis for direct elevation of the epiglottis (Group AWS-D; n = 30). MeasurementsPercentage of glottic opening (POGO) score at the time of laryngeal exposure, time required for intubation, and intubation difficulty scale (IDS) were measured. The frequency of postoperative sore throat and hoarseness also were noted. Main ResultsPatient demographics did not differ among the groups. In Groups AWS-I and AWS-D, IDS scores were reduced significantly, and the percentages of glottic opening were significantly improved, compared with the Macintosh group. Time to place the endotracheal tube was significantly shortest in Group AWS-I. In one case from each group, intubation within two attempts failed and a different approach was required. ConclusionThe AWS offers better intubation conditions than the Macintosh laryngoscope during nasotracheal intubation. The AWS may be used to elevate the epiglottis both directly and indirectly for nasotracheal intubation.

Parker Flex-Tip Tube® provides higher intubation success with the Pentax-AWS Airwayscope® despite the AWS tip being inserted into the vallecula

The Parker Flex-Tip(®) tube, in combination with the Pentax-Airwayscope(®) (AWS), is anecdotally reported to facilitate intubation when the AWS tip fails to be inserted behind the epiglottis. We examined whether the Parker tube facilitates intubation when the AWS tip is inserted into the vallecula. Forty patients were randomly assigned into either the standard or Parker tube group. Following general anesthesia induction, AWS intubation was attempted with the blade tip inserted into the vallecula. After obtaining an optimal laryngeal view, the tube was advanced toward the glottis. The laryngoscopist allowed additional adjustment of the blade tip direction when the first tube insertion failed because of involvement or folding of the epiglottis resulting from advancement of the tube. The primary outcome was defined as the success rate for intubation and secondary outcome as the time needed for tube placement. The Parker tube provided both a higher intubation success rate (17/20 vs. 4/20, P<0.01), and a faster intubation time (17±5 s vs. 25±4 s, P<0.01), than the standard tube. We conclude the use of the Parker tube in combination with the AWS is an optional technique allowing the laryngoscopist to obtain more reliable intubation success despite insertion of the AWS tip into the vallecula.

Comparison of Pentax-AWS Airwayscope video laryngoscope, Airtraq optic laryngoscope, and Macintosh laryngoscope during cardiopulmonary resuscitation under cervical stabilization: a manikin study

The 2010 American Heart Association or European Resuscitation Council guidelines for cardiopulmonary resuscitation emphasize that rescuers should minimize interruption of chest compressions, even for endotracheal intubation. Cervical stabilization should also be maintained during traumatic cardiac arrest. The utility of the Pentax-AWS Airwayscope (AWS) video laryngoscope and Airtraq (ATQ) optic laryngoscope for airway management has been reported under cervical stabilization. We first evaluated ATQ utility during chest compression with or without cervical stabilization and then compared the AWS, ATQ, and Macintosh laryngoscope (McL) during chest compressions under cervical stabilization in a manikin. In the first trial, 19 novice doctors performed tracheal intubation with ATQ during chest compression with or without cervical stabilization. In the second trial, 21 novice doctors performed tracheal intubation on a manikin with cervical stabilization using AWS, ATQ, and McL with or without chest compression in a manikin. The rate of successful intubation, time to intubation, and subjective difficulty of use (visual analog scale) were recorded. In the first trial, intubation time during chest compression was significantly shortened under cervical stabilization compared to without cervical stabilization (P < 0.05). In the second trial, using McL, 3 participants failed to perform tracheal intubation without chest compression and 11 failed during chest compression (P < 0.05). Using ATQ, all intubations were successful without chest compression, but 5 failed during chest compression (P < 0.05). Intubation time was significantly prolonged by chest compression using McL or ATQ (P < 0.05). All participants successfully secured the airway with AWS regardless of chest compression, and chest compression did not prolong intubation time. Chest compression worsened the score on the visual analog scale of laryngoscopy in the McL trial (P < 0.05), but not in ATQ or AWS trials. Difficulty of tube passage through the glottis increased with chest compression with the McL and ATQ (P < 0.05) but not with AWS. The AWS was superior to McL and ATQ for endotracheal intubation during simulated cervical stabilization and chest compression.

Efficacy of Bronchofiberscope Combined with Pentax-AWS Airwayscope in Patients with Unanticipated Difficult Airway with Lingual Tonsil Hyperplasia

33歳，男性．171cm，60kg．鼻中隔側弯症に対し，鼻中隔矯正術が予定された．開口3横指，後屈は軽度制限あり．口腔内診察において，扁桃肥大II度，舌の肥大を認め，問診にて睡眠時無呼吸症候群が疑われた．フェンタニル100μg，プロポフォール60mgで全身麻酔の導入を行ったが，換気困難であり，経口エアウェイ挿入を要した．通常のマッキントッシュ型喉頭鏡では挿管が困難なため，気管支ファイバースコープ（BFS）の挿管を経口的に試みたが，声門の視認ができず，マッキントッシュ型喉頭鏡での喉頭展開補助下で行うも不成功であった．次にエアウェイスコープ®（AWS）を挿入したが，喉頭蓋と声門の一部は視認できるものの喉頭展開ならびに気管挿管は不可能であった．ほかの麻酔科医にAWSを保持してもらいながら，BFSを口腔内で誘導し挿管に成功した．挿管困難の原因として喉頭蓋の肥厚，咽喉頭肥大と併せて，舌扁桃肥大（lingual tonsil hyperplasia）が疑われた．本症例では，BFS挿管が困難であり，AWS単独にても挿管は不可能であった．AWSにてBFS挿管の誘導を行うことはそれぞれ単独での挿管困難症例に有効であった．

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

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. 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. 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. 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.