The Pentax-AWS®rigid indirect video laryngoscope: clinical assessment of performance in 320 cases

Indirect laryngoscopy is more effective than direct laryngoscopy when tracheal intubation is performed by novice operators: a systematic review, meta-analysis, and trial sequential analysis

PURPOSE

We sought to perform a systematic review and meta-analysis to determine whether indirect laryngoscopy has an advantage over direct laryngoscopy in terms of the tracheal intubation rate, glottic visualization, and intubation time when used by novice operators.

METHODS

We extracted adult prospective randomized trials comparing tracheal intubation with indirect vs direct laryngoscopy in novice operators from electronic databases. We extracted the following data from the identified studies: success rate, glottic visualization, and intubation time. Data from each trial were combined via a random-effects model to calculate the pooled relative risk (RR) or weighted mean difference (WMD) with a 95% confidence interval (CI). We also performed a trial sequential analysis.

RESULTS

We included 15 articles (17 trials) comprising 2,290 patients in the systematic review. Compared with the direct laryngoscopy, indirect laryngoscopy improved success rate (RR, 1.15; 95% CI, 1.07 to 1.24; P = 0.0002; I2 = 88%), glottic visualization (RR, 1.76; 95% CI, 1.36 to 2.28; P < 0.001; I2 = 85%), and intubation time (WMD, -9.06 sec; 95% CI, -16.4 to -1.76; P = 0.01; I2 = 98%) in tracheal intubation. Trial sequential analysis showed that the total sample size was sufficient to analyze the success rate and intubation time.

CONCLUSION

In this systematic review, we found that the tracheal intubation success rate, glottic visualization, and intubation time were improved when novice operators used indirect laryngoscopy rather than direct laryngoscopy. Trial sequential analysis results indicated that the sample size was sufficient for examining the success rate and intubation time.

STUDY REGISTRATION

PROSPERO (CRD42022309045); first registered 4 September 2022.

Implementation of video laryngoscopes and the development in airway management strategy and prevalence of difficult tracheal intubation: A national cohort study

BACKGROUND

We aimed to determine the development in the use of video laryngoscopy over a 9-year period, and its possible impact on airway planning and management.

METHODS

We retrieved 822,259 records of tracheal intubations recorded from 2008 to 2016 in the Danish Anaesthesia Database. The circumstances regarding pre-operative airway assessment, the scheduled airway management plan and the actual airway management concerning video laryngoscopy were reported for each year of observation. Further, the association between year of observation and various airway management related outcomes was evaluated by multivariate logistic regression.

RESULTS

There was a significant increase in airway management with 'advanced technique successfully used within two attempts' from 2.7% in 2008 to 15.5% in 2016 (p < .0001). This predominantly reflects use of video laryngoscopy. The prevalence of tracheal intubations 'scheduled for video laryngoscopy' increased from 3.5% in 2008 to 10.6% in 2016 (p < .0001). We found a significant increase in the prevalence of anticipated difficulties with intubations by direct laryngoscopy from 1.8% in 2008 to 5.2% in 2016 (p < .0001). The prevalence of failed tracheal intubations decreased from 0.14% in 2008 to 0.05% in 2016 (p < .0001).

CONCLUSION

From 2008 to 2016, a period of massive implementation of video laryngoscopes, a significant change in airway management behaviour was recorded. Increasingly, video laryngoscopy is becoming a first-choice device for both acute and routine airway management. Most importantly, the data showed a noticeable reduction in failed intubation over the time of observation.

Recent Advances in Videolaryngoscopy for One-Lung Ventilation in Thoracic Anesthesia: A Narrative Review

Since their advent, videolaryngoscopes have played an important role in various types of airway management. Lung isolation techniques are often required for thoracic surgery to achieve one-lung ventilation with a double-lumen tube (DLT) or bronchial blocker (BB). In the case of difficult airways, one-lung ventilation is extremely challenging. The purpose of this review is to identify the roles of videolaryngoscopes in thoracic airway management, including normal and difficult airways. Extensive literature related to videolaryngoscopy and one-lung ventilation was analyzed. We summarized videolaryngoscope-guided DLT intubation techniques and discussed the roles of videolaryngoscopy in DLT intubation in normal airways by comparison with direct laryngoscopy. The different types of videolaryngoscopes for DLT intubation are also compared. In addition, we highlighted several strategies to achieve one-lung ventilation in difficult airways using videolaryngoscopes. A non-channeled or channeled videolaryngoscope is suitable for DLT intubation. It can improve glottis exposure and increase the success rate at the first attempt, but it has no advantage in saving intubation time and increases the incidence of DLT mispositioning. Thus, it is not considered as the first choice for patients with anticipated normal airways. Current evidence did not indicate the superiority of any videolaryngoscope to another for DLT intubation. The choice of videolaryngoscope is based on individual experience, preference, and availability. For patients with difficult airways, videolaryngoscope-guided DLT intubation is a primary and effective method. In case of failure, videolaryngoscope-guided single-lumen tube (SLT) intubation can often be achieved or combined with the aid of fibreoptic bronchoscopy. Placement of a DLT over an airway exchange catheter, inserting a BB via an SLT, or capnothorax can be selected for lung isolation.

The effect of cricoid pressure on tracheal intubation in adult patients: a systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to assess the impact of cricoid pressure (CP) application on intubation outcomes.

SOURCE

Electronic databases (i.e., MEDLINE, PubMed, Embase, and Cochrane review) were searched from inception to 2 June 2020 for randomized-controlled trials that assessed the intubation outcomes in adult patients using laryngoscopic approaches with and without the application of CP (i.e., CP vs non-CP group). The primary outcome was the successful first-attempt intubation rate (SFAIR), and the secondary outcomes were intubation time, incidences of poor laryngoscopic views (i.e., Cormack and Lehane grade 3-4), airway complications, and pulmonary aspiration.

PRINCIPAL FINDINGS

A total of five trials (published from 2005 to 2018) were included, and all tracheal intubations were performed by anesthesiologists or nurse anesthetists with a video (n = 3) or Macintosh laryngoscope (n = 2) in the operating room. We found no significant difference in SFAIR (risk ratio [RR], 0.98; P = 0.37), incidence of poor laryngoscopic views (RR, 1.49; P = 0.21), and risk of sore throat (RR, 1.17; P = 0.73) between the two groups. Nevertheless, the intubation time on the first successful attempt was slightly longer (weighted mean difference = 4.40 sec, P = 0.002) and risk of hoarseness was higher (RR, 1.70; P = 0.03) in the CP group compared with in the non-CP group. The secondary outcome "pulmonary aspiration" was not analyzed because only one trial was available.

CONCLUSION

The application of CP did not have a negative impact on the SFAIR or laryngoscopic view. Nevertheless, this maneuver may slightly prolong intubation time and increase the risk of postoperative hoarseness.

A comparison of McGrath MAC, Pentax AWS, and Macintosh direct laryngoscopes for nasotracheal intubation: a randomized controlled trial

Purpose

Videolaryngoscopy in nasotracheal intubation has been reported to be better than direct laryngoscopy. The most suitable type of videolaryngoscope remains unknown. This study aimed to compare two videolaryngoscopes (McGrath MAC and Pentax AWS) with a Macintosh laryngoscope during nasotracheal intubation.

Methods

Overall, 123 patients older than 18 with normal airways who needed nasotracheal intubation were randomly allocated into three groups: Macintosh (n=41), McGrath (n=41), and Pentax (n=41). Intubation time was the primary outcome and subdivided into three steps: nose to oropharynx, oropharynx to laryngeal inlet, and laryngeal inlet to trachea. Time required, ease of each step, glottic view grade, modified nasal intubation–difficulty score, and subjective difficulty were evaluated.

Results

Intubation time among the three groups was not significantly different (Macintosh 34.6±8.1 seconds, McGrath 35.2±7.9 seconds, Pentax 36.2±9.7 seconds; p=0.727). While the glottal view was better with videolaryngoscopes (I/IIa/IIb/III 36.6%/36.6%/19.5%/7.3% vs 82.9%/9.8%/7.3%/0%, vs 63.4%/29.3%/4.9%/2.4%, p=0.000), modified nasal intubation–difficulty score and subjective difficulty and ease of each step were not significantly different. However, the Pentax took longest for the second step (11.8±6.3 vs 10.3±3.5 vs 15.1±7.6 seconds, p=0.001) but was shortest for the third step (2.9±2.6 vs 4.4±5.6 vs 1.7±0.7 seconds, p=0.001).

Conclusion

The McGrath MAC and Pentax AWS showed no benefits in intubation time or difficulty, despite better glottal views, compared to the Macintosh laryngoscope in nasotracheal intubation. Additionally, videolaryngoscopes had variable performance at different steps of nasotracheal intubation.

Comparison of Pentax Airway Scope and Macintosh laryngoscope for orotracheal intubation in children: A randomised non-inferiority trial

BACKGROUND

Pentax Airway Scope (AWS) is a recently developed videolaryngoscope for use in both normal and difficult airways, yet its use in paediatric patients has not been established. The purpose of this study was to evaluate the efficacy of the Pentax AWS regarding intubation time, laryngeal view and ease of intubation in paediatric patients with normal airway, compared to Macintosh laryngoscope.

METHOD

A total of 136 paediatric patients aged 1-10 with American Society of Anaesthesiologists physical status I or II undergoing general anaesthesia were randomly allocated into two groups: Macintosh laryngoscope (n = 68) and Pentax Airway Scope (n = 68). Primary outcome was intubation time. Cormack-Lehane laryngeal view grade, application of optimal laryngeal external manipulation, intubation difficulty scale, intubation failure rate and adverse events were also measured.

RESULT

No significant difference was observed between the two groups regarding intubation time (P = 0.713). As for the laryngeal view grade, the Pentax group resulted in lower graded cases compared to the Macintosh group (P = 0.000). No optimal laryngeal external manipulation application was required in the Pentax group. Intubation difficulty scale resulted in lower values for Pentax group (P = 0.001). Failure rate was not different between the two groups (P = 0.619). There were significantly more teeth injury cases in the Pentax group than Macintosh group (P = 0.042).

CONCLUSION

Pentax Airway Scope provided similar intubation time and success rate, while improving laryngeal view, compared to Macintosh laryngoscopy in children with normal airway. When using Pentax AWS in children, however, the risk of teeth injury may increase.

Videolaryngoscopy versus direct laryngoscopy for nasotracheal intubation: A systematic review and meta-analysis of randomised controlled trials

STUDY OBJECTIVE

Nasotracheal intubation (NTI) is a common practice in the oral and maxillofacial surgeries. A systematic review and meta-analysis was performed to determine whether videolaryngoscopy (VL) compared with direct laryngoscopy (DL) can lead to better outcomes for NTI in adult surgical patients.

MEASUREMENTS

Only randomised controlled trials comparing VL and DL for NTI were included. The primary outcome was overall success rate and the second outcomes were first-attempt success rate, intubation time, rate of Cormack and Lehane classification 1, rate of Magill Forceps used, rate of postoperative sore throat, and ease of intubation.

MAIN RESULTS

Fourteen studies with 20 comparisons (n = 1052) were included in quantitative synthesis. The overall success rate was similar between two groups (RR, 1.03; p = 0.14; moderate-quality evidence). VL was associated with a higher first-attempt success rate (RR 1.09; p = 0.04; low-quality evidence), a shorten intubation time (MD-6.72 s; p = 0.0001; low-quality evidence), a higher rate of Cormack and Lehane classification 1 (RR, 2.11; p < 0.01; high-quality evidence), a less use of the Magill forceps (RR, 0.11; p < 0.01; high-quality evidence) and a lower incidence of postoperative sore throat (RR, 0.50; p = 0.03; high-quality evidence). Subgroup analysis based on whether with a difficult airway showed higher overall success (p < 0.01) and first-attempt success rates with VL (p = 0.04) in patients with difficult airways; however, these benefits was not shown in patients with a normal airway (p > 0.05); Subgroup analysis based on operators' experience showed that success rate did not differ between groups (p > 0.05), but intubation time was shortened by more than 50s by non-experienced operators (p < 0.05). Subgroup analysis based on different devices used showed that only non-integrated VL led to a shorter intubation time (p < 0.05).

CONCLUSIONS

The use of VL does not increase the overall success rate of NTI in adult patients with general anesthesia, but it improves the first-attempt success rate and laryngeal visualization, and shortens the intubation time. VL is particularly beneficial for patients with difficult airways.

Comparison of the Karl Storz Video Laryngoscope with the Macintosh Laryngoscope for Intubating Difficult Airway: A Manikin Study

Objective

To compare the Karl Storz video laryngoscope (KSVL) with the conventional Macintosh laryngoscope in simulated difficult airway scenarios, using a Laerdal resuscitation manikin.

Methods

This was a prospective comparative study. The scenarios were normal airway, reduced mouth opening, tongue oedema and cervical spine immobilisation. Thirty-five doctors performed endotracheal intubation with both devices in each of the scenarios. The outcome measures were the successful rate of intubation, time taken for intubation, vocal cord visualisation, and ease of intubation. We also surveyed the doctors' preference for the intubation devices.

Results

The use of the KSVL resulted in significantly better laryngoscopic grading than the Macintosh laryngoscope in all four scenarios. The mean time of intubation in the cervical spine immobilisation scenario was significantly shorter with the KSVL than the Macintosh laryngoscope (12.56 sec and 14.00 sec, respectively; P=0.049). The mean time of intubation in the tongue oedema scenario was shorter with the KSVL than the Macintosh laryngoscope (19.37 sec and 22.04 sec, respectively), although this was not statistically significant (P=0.546). There was no difference in the mean time required for intubation in the normal and reduced mouth opening scenarios. There was no significant difference in the success rate in all four scenarios. The ease of intubation score of the KSVL was significantly better than that of the Macintosh laryngoscope in all three difficult airway scenarios

Conclusions

Our study showed that the KSVL provided a better glottic view in both normal and difficult airways than the conventional Macintosh laryngoscope. It also showed an advantage over the conventional Macintosh laryngoscope in the time required for intubation in patients under cervical immobilisation.

Comparison of the Pentax AirwayScope and McGrath MAC videolaryngoscope for endotracheal intubation in patients with a normal airway

Various videolaryngoscopes (VLs) have been developed to provide a better laryngeal view and facilitate difficult intubations. The goal of this study was to compare 2 VLs, the Pentax AWS and the McGrath VL, with respect to intubation time and ease of intubation.One hundred forty patients aged 19 to 65 years (American Society of Anesthesiologists classification I or II), who required tracheal intubation for elective surgery, were randomly assigned to 1 of the 2 groups: the Pentax AWS (n = 70) or the McGrath VL (n = 70). The primary outcome was time to intubation (TTI) measured by a blind observer. The intubation difficulty scale (IDS), percentage of glottic opening (POGO) scale, glottic grade, use of optimal external laryngeal manipulation (OELM), and ease of intubation were also recorded.The Pentax AWS provided a better laryngeal view than the McGrath VL with respect to the Cormack-Lehane (CL) glottic grade (1/2a/2b) (63/7/0 vs 43/24/3, P < .001) and the POGO scale (median [interquartile range, IQR]) (100 [100-100] vs 100 [80-100], P < .001). The IDS was significantly lower in the Pentax AWS group compared with the McGrath VL group (median [IQR]) (0 [0-0] vs 0 [0-1], P < .001). However, the TTI was similar in both the Pentax AWS and McGrath VL groups (median [IQR]) (30 [27-34] vs 32 [27-35] seconds, P = .440). OELM and ease of intubation were also similar between the 2 groups.The Pentax AWS offered a superior laryngeal view compared with the McGrath VL. There was no significant difference in either the intubation time or ease of intubation using these 2 devices in patients with normal airways.

Effect of availability of video laryngoscopy on the use of fiberoptic intubation in school-aged children with microtia

BACKGROUND

With the increasing popularity of video laryngoscopy during intubation of pediatric patients with normal or difficult airways, fiberoptic-assisted tracheal intubation, traditionally considered the gold standard for difficult intubation, may become underused.

AIM

We aimed to assess the use of airway management techniques before and after introduction of video laryngoscopy in a cohort of school-aged children with microtia, who are at increased risk of difficult intubation.

METHODS

We retrospectively reviewed intubation devices used for all pediatric patients with microtia who had undergone reconstructive ear surgery at a single institution during the period January 2008 to December 2012. In each case, we identified the original airway management technique and success rate, as well as success rate for subsequent rescue techniques. The use of fiberoptic-assisted tracheal intubation was compared before and after introduction of a pediatric blade for the Pentax-AWS video laryngoscope.

RESULTS

This study included 537 consecutive intubation procedures; 264 before and 273 after introduction of the pediatric airway scope. Elective use of fiberoptic-assisted tracheal intubation for anticipated difficult intubation was significantly less after introduction of the pediatric airway scope (before: 19 of 79, 24% vs after: 3 of 79, 4%; odds ratio 8.02; 95% confidence interval, 2.27 to 28.39; P = .0003), which achieved a 100% success rate when used as the primary technique in both routine and difficult airways. All 5 cases of failed direct laryngoscopy were rescued by the pediatric airway scope, thus eliminating emergency use of fiberscopy.

CONCLUSION

Introduction of a pediatric video laryngoscope resulted in a substantial decrease in the use of fiberoptic-assisted tracheal intubation. This change in intubation method might not influence the success rate of intubation in experienced hands but could be relevant for novice users.

Efficacy of Pentax airway scope versus Macintosh laryngoscope when used by novice personnel: A prospective randomized controlled study

Objective

To determine whether intubation education using the Pentax Airway Scope (AWS) in normal airways is more useful than direct laryngoscopy (Macintosh laryngoscope) in novice personnel.

Methods

Eleven intern doctors without intubation experience performed 60 sequential intubations with each device on a manikin and 10 sequential intubations in adult patients. The time required for successful intubation, percentage of glottic opening (POGO) score, number of intubation attempts, and number of dental injuries were analyzed for each intubation technique.

Results

The mean (standard deviation) time required for successful intubation decreased as the number of intubations increased and was significantly shorter with the Pentax AWS than direct laryngoscope [22.6 (7.3) vs. 29.6 (10.0) and 33.0 (8.0) vs. 44.7 (5.6) s, respectively] in both the manikin and clinical studies. The Pentax AWS was also associated with higher POGO scores than the direct laryngoscope [81.7 (8.9) vs. 55.1 (13.2) and 80.9 (9.7) vs. 49.6 (16.5), respectively] and fewer intubation attempts. Fewer dental injuries occurred with the Pentax AWS in the manikin study.

Conclusions

Novices performed intubation more rapidly and easily with an improved laryngeal view using the Pentax AWS. We suggest that intubation education with video laryngoscopy should be mandatory along with direct laryngoscope training.

A comparison of the video laryngoscopes with Macintosh laryngoscope for nasotracheal intubation

Nasotracheal intubation (NTI) is usually required in patients undergoing maxillofacial surgery. Though video-scopes have been demonstrated to perform well in oral endotracheal intubation, limited information is available concerning NTI. The aim of the study is to compare the efficiency of video-scopes and the traditional direct laryngoscopy in NTI. One hundred and eight patients scheduled for elective oro-maxillofacial surgery under nasotracheal intubation general anesthesia were randomly allocated into one of 3 groups of GlideScope, Pentax AirWay Scope, or Macintosh laryngoscope respectively. The primary outcome measures were total intubation time and each separate time interval (time A: for placement for the nasotracheal tube from selected nostril to oropharynx; time B: for use of devices to view the glottic opening; time C: for advancing nasotracheal tube from oropharynx into trachea and removing the scope from the oral cavity). The secondary outcomes were measurement of scores of modified naso-intubation difficulty scale (MNIDS) and attempts at intubation.

RESULTS

Mean total intubation time and time C interval were taken with GlideScope (33.1 s and 9.7 s), Pentax (38.4 s and 12.9 s), and Macintosh (42.2 s and 14.9 s) respectively. There was a significant difference among the groups (total time, P = 0.03; time C, P = 0.02). The median score of MNIDS was significantly lower using GlideScope or Pentax compared with using Macintosh in NTI (P = 0.037) and difficult intubation grading by MNIDS presented as easier in the GlideScope group than in the Macintosh group (0.016). Using GlideScope, intubation was successful at the first attempt in 80% patients whereas only 65% and 72.5% with the Pentax and Macintosh (P = 0.02).

CONCLUSION

As compared with the Macintosh laryngoscope, the GlideScope video laryngoscope facilitated nasotracheal intubations with shortened intubation time and reduced intubation difficulty in patients undergoing oromaxillofacial surgery.

Comparison of glottic views and intubation times in the supine and 25 degree back-up positions

BACKGROUND

We explored whether positioning patients in a 25° back-up sniffing position improved glottic views and ease of intubation.

METHODS

In the first part of the study, patients were intubated in the standard supine sniffing position. In the second part, the back of the operating table was raised 25° from the horizontal by flexion of the torso at the hips while maintaining the sniffing position. The best view obtained during laryngoscopy was assessed using the Cormack and Lehane classification and Percentage of Glottic Opening (POGO) score. The number of attempts at both laryngoscopy and tracheal intubation, together with the use of ancillary equipment and manoeuvres were recorded. The ease of intubation was indirectly assessed by recording the time interval between beginning of laryngoscopy and insertion of the tracheal tube.

RESULTS

Seven hundred eighty one unselected surgical patients scheduled for non-emergency surgery were included. In the back-up position, ancillary laryngeal manoeuvres, which included cricoid pressure, backwards upwards rightward pressure and external laryngeal manipulation, were required less frequently (19.6 % versus 24.6 %, p = 0.004). The time from beginning of laryngoscopy to insertion of the tracheal tube was 14 % shorter (median time 24 versus 28 s, p = 0.031) in the back-up position. There was no significant difference in glottic views.

CONCLUSIONS

The 25° back-up position improved the ease of intubation as judged by the need for fewer ancillary manoeuvres and shorter time for intubation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02934347 registered retrospectively on 14th Oct 2016.

Usefulness of video-laryngoscopy with the Airway Scope for intubation performance and learning: an experimental manikin controlled study

Background

Different video-laryngoscopes (VDLs) for endotracheal intubation (ETI) have recently been developed. We compared the performance of the VDL Airway Scope (AWS) with the direct laryngoscopy by Macintosh (DLM) for ETI success, time and learning.

Methods

We performed an experimental manikin controlled study. Twenty experienced (experts) and 40 inexperienced operators (novices) for DLM-ETI were enrolled. None of them had experience with the use of AWS-VDL. Novices were assigned to start learning with DLM or AWS, and two sub-groups of 20 novices were formed. Experts group constituted the control group. Each participant performed 10 ETI attempts with each device on the same standard manikin. The primary endpoint was the ETI success probability. Secondary endpoints were ETI time, technical validity and qualitative evaluation for each technique. We also assessed the learning order and the successive attempts effects for these parameters.

Results

Overall, 1200 ETI attempts were performed. ETI success probability was higher with the AWS than with the DLM for all operators (98 vs. 81 %; p < 0.0001) and for experts compared to novices using devices in the same order (97 vs. 83 %; p = 0.0002). Overall ETI time was shorter with the AWS than with the DLM (13 vs. 20 s; p < 0.0001) and for experts compared to novices using devices in the same order (11 vs. 21 s; p < 0.0001). Among novices, those starting learning with AWS had higher ETI success probability (89 vs. 83 %; p = 0.03) and shorter ETI time (18 vs. 21 s; p = 0.02). Technical validity was found better with the AWS than DLM for all operators. Novices expressed global satisfaction and device preference for the AWS, whereas experts were indifferent.

Conclusions

AWS-VDL permits faster, easier and more reliable ETI compared to the DLM whatever the previous airway ETI experience and could be a useful device for DLM-ETI learning.

Obstetric Anaesthetists' Association and Difficult Airway Society guidelines for the management of difficult and failed tracheal intubation in obstetrics

The Obstetric Anaesthetists' Association and Difficult Airway Society have developed the first national obstetric guidelines for the safe management of difficult and failed tracheal intubation during general anaesthesia. They comprise four algorithms and two tables. A master algorithm provides an overview. Algorithm 1 gives a framework on how to optimise a safe general anaesthetic technique in the obstetric patient, and emphasises: planning and multidisciplinary communication; how to prevent the rapid oxygen desaturation seen in pregnant women by advocating nasal oxygenation and mask ventilation immediately after induction; limiting intubation attempts to two; and consideration of early release of cricoid pressure if difficulties are encountered. Algorithm 2 summarises the management after declaring failed tracheal intubation with clear decision points, and encourages early insertion of a (preferably second-generation) supraglottic airway device if appropriate. Algorithm 3 covers the management of the 'can't intubate, can't oxygenate' situation and emergency front-of-neck airway access, including the necessity for timely perimortem caesarean section if maternal oxygenation cannot be achieved. Table 1 gives a structure for assessing the individual factors relevant in the decision to awaken or proceed should intubation fail, which include: urgency related to maternal or fetal factors; seniority of the anaesthetist; obesity of the patient; surgical complexity; aspiration risk; potential difficulty with provision of alternative anaesthesia; and post-induction airway device and airway patency. This decision should be considered by the team in advance of performing a general anaesthetic to make a provisional plan should failed intubation occur. The table is also intended to be used as a teaching tool to facilitate discussion and learning regarding the complex nature of decision-making when faced with a failed intubation. Table 2 gives practical considerations of how to awaken or proceed with surgery. The background paper covers recommendations on drugs, new equipment, teaching and training.

Comparison of McGrath Series 3 and Macintosh Laryngoscopes for Tracheal Intubation in Patients With Normal Airway by Inexperienced Anesthetists: A Randomized Study

Difficult and failed intubations account for the major causes of morbidity and mortality in current anesthetic practice. Several devices including McGrath Series 3 videolaryngoscope are available which may facilitate tracheal intubation by improving view of the larynx compared with Macintosh blade laryngoscopy. But no studies demonstrate whether McGrath Series 3 performs better than Macintosh laryngoscope in normal airway intubations by inexperienced anesthetists so far. We therefore designed this randomized controlled study to compare McGrath with Macintosh in routine tracheal intubation performed by inexperienced anesthetists.In total, 180 adult patients with normal-appearing airways requiring orotracheal intubation for elective surgery were randomly allocated to be intubated by 9 inexperienced anesthetists with McGrath or Macintosh. The primary outcome was time to intubation. Ease of intubation was assessed by a 5-point ordinal scale. Intubation attempts/failures, best laryngoscopy view using the Cormack-Lehane grade, associated complications and hemodynamic changes during intubation were recorded.We found that there was no significant difference between McGrath and Macintosh in the median time to intubation (P = 0.46); the Cormack-Lehane views attained using McGrath were superior (P < 0.001); the difference of ease of intubation was statistically significant (P = 0.01). No serious trauma occurred in both groups. And there was statistically significant difference in the systolic blood pressure changes between 2 groups (P < 0.05).We demonstrated that in orotracheal intubation in patients with normal airway by inexperienced anesthetists, McGrath compared with the Macintosh allows superior glottis views, greater ease of intubation, less complications, and hemodynamic changes with noninferior intubation time. And it remained a potential selection for inexperienced anesthetists in uncomplicated intubation.

Comparison of Pentax-AWS Airwayscope and Glidescope for Infant Tracheal Intubation by Anesthesiologists during Cardiopulmonary Arrest Simulation: A Randomized Crossover Trial

BACKGROUND

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 Airwayscope (AWS) with the Glidescope (GS) during chest compressions on an infant manikin.

METHODS

Twenty-four anesthesiologists with more than two years of experience performed tracheal intubation on an infant manikin using the AWS and GS, with or without chest compressions.

RESULTS

In GS trials, none of the participants failed without compressions, while three failed with compressions. In AWS trials, all participants succeeded regardless of chest compressions. Intubation time was significantly longer with chest compressions with the GS (P < 0.05), but not with the AWS. Difficulty of operation on a visual analog scale (VAS) for laryngoscopy did not increase significantly with chest compressions with either the GS or the AWS, while the VAS for tube passage through the glottis increased with compressions with the GS, but not with the AWS.

CONCLUSION

We conclude that in infant simulations managed by anesthesiologists, the AWS performed better than the GS for endotracheal intubation with chest compressions.

Rapid-Sequence Intubation in the Left-Lateral Tilt Position in a Pregnant Woman with Premature Placental Abruption Utilizing a Videolaryngoscope

Case A 24-year-old pregnant woman was admitted to our hospital with decreased fetal heart rate. Obstetric examination revealed premature placental abruption; emergent caesarean section was planned under general anesthesia. On entering the operating room, the patient showed severe vital sign deterioration (blood pressure, 75/45 mm Hg; heart rate, 142 beats per minute). As left uterine displacement may worsen the premature placental abruption, the patient was placed in the left-lateral tilt position by rotating the operating table to release compression on the inferior vena cava by theuterus. To avoid circulatory collapse, rapid-sequence intubation was performed in this position. Tracheal intubation was performed with the Pentax-AWS Airwayscope (AWS videolaryngoscope, AWS; HOYA, Japan) to obtain a good laryngeal view and minimize stress from laryngoscopy. After sufficient oxygenation, 120 mg of thiopental was administered. A second anesthesiologist performed cricoid pressure and 50 mg of rocuronium was administered after confirming loss of consciousness. This was followed by insertion of the AWS with a thin intlock into the mouth. Tracheal intubation was performed uneventfully. Discussion Rapid-sequence intubation in the left-lateral tilted position with the AWS videolaryngoscope may be beneficial for pregnant women with vital sign deterioration.

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

PURPOSE

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).

METHODS

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).

RESULTS

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.

CONCLUSION

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.

Awake tracheal intubation using Pentax airway scope in 30 patients: A Case series

BACKGROUND AND AIMS

Pentax airway scope (AWS) has been successfully used for managing difficult intubations. In this case series, we aimed to evaluate the success rate and time taken to complete intubation, when AWS was used for awake tracheal intubation.

METHODS

We prospectively evaluated the use of AWS for awake tracheal intubation in 30 patients. Indication for awake intubation, intubation time, total time to complete tracheal intubation, laryngoscopic view (Cormack and Lehane grade), total dose of local anaesthetic used, anaesthetists rating and patient's tolerance of the procedure were recorded.

RESULTS

The procedure was successful in 25 out of the 30 patients (83%). The mean (standard deviation) intubation time and total time to complete the tracheal intubation was 5.4 (2.4) and 13.9 (3.7) min, respectively in successful cases. The laryngeal view was grade 1 in 24 and grade 2 in one of 25 successful intubations. In three out of the five patients where the AWS failed, awake tracheal intubation was successfully completed with the assistance of flexible fibre optic scope (FOS).

CONCLUSION

Awake tracheal intubation using AWS was successful in 83% of patients. Success rate can be further improved using a combination of AWS and FOS. Anaesthesiologists who do not routinely use FOS may find AWS easier to use for awake tracheal intubation using an oral route.

A review of video laryngoscopes relevant to the intensive care unit

The incidence of difficult direct intubation in the intensive care unit (ICU) is estimated to be as high as 20%. Recent advances in video-technology have led to the development of video laryngoscopes as new intubation devices to assist in difficult airway management. Clinical studies indicate superiority of video laryngoscopes relative to conventional direct laryngoscopy in selected patients. They are therefore an important addition to the armamentarium of any clinician performing endotracheal intubation. We present a practical review of commonly available video laryngoscopes with respect to design, clinical efficacy, and safety aspects relevant to their use in the ICU.

Pentax Airway Scope® vs Macintosh laryngoscope for tracheal intubation in adult patients: a systematic review and meta-analysis

The Pentax Airway Scope(®) is a single-use optical videolaryngoscope designed to assist with difficult tracheal intubation. We systematically reviewed the efficacy of the Pentax Airway Scope with that of a conventional laryngoscope for tracheal intubation in adults with 'normal' and 'difficult' airways. We included 17 randomised controlled trials with a total of 1801 participants. We used the DerSimonian and Laird random-effects model to calculate pooled relative risk or weighted mean differences. The relative risk (95% CI) of a Cormack-Lehane grade-1 laryngeal view was 2.40 (1.76-2.49) with the Pentax Airway Scope compared with the Macintosh laryngoscope, p < 0.00001. We found no other differences between the two laryngoscopes. Despite a superior laryngeal view, the Pentax Airway Scope provides little clinical benefit over the conventional laryngoscope.

Comparison of the McGrath MAC video laryngoscope and the Pentax Airwayscope during chest compression: a manikin study

We tested the utility of the McGrath MAC^® (McG) video laryngoscope during chest compression compared with the Pentax Airwayscope^® (AWS). We recruited 59 participants into the simulation study. The difference in the time to intubation (TTI [sec]) between without and with chest compression was significant for the AWS attempts (median 13, range 6–28 vs. median 15, range 6–72, p = 0.0247) but not significant for the McG attempts (median 16, range 6–75 vs. median 16, range 6–71); however, the difference of the TTIs is not serious clinically. The utility of the two devices during chest compressions is almost similar although their characteristics are different.

Incidence and predictors of difficult nasotracheal intubation with airway scope

Purpose

The airway scope (AWS) improves views of the larynx during orotracheal intubation. However, the role of the AWS in routine nasotracheal intubation has not been studied adequately.

Methods

One hundred and three patients undergoing dental and maxillofacial surgery that required general anesthesia and nasotracheal intubation were enrolled. The study was approved by our Institution Review Board, and written informed consent was obtained from all patients. We evaluated the success rate of AWS intubation and the incidence of difficult nasotracheal intubation using a modified intubation difficulty scale (IDS) to examine preoperative characteristics and intubation profiles. Categories were difficult intubation (IDS ≥5), mildly difficult (IDS = 1–4), and intubation without difficulty (IDS = 0). We also assessed the incidence of the use of Magill forceps or cuff inflation (the cuff of endotracheal tube is inflated with 10–15 ml air) to guide the endotracheal tube into the glottis.

Results

AWS nasotracheal intubation was 100 % successful. The cuff inflation technique was used in 37 patients. Neither Magill forceps nor other devices were needed for any patient during AWS use. The incidence of difficult nasotracheal intubation was 10 % (n = 10). Of the patients, 61 % (n = 63) had mildly difficult intubation and 29 % (n = 30) had no difficulty. Patients with difficult intubation were more likely to be male and to have a larger tongue and a higher Cormack grade than in the other two groups. Complications, involving minor soft tissue injury, were observed in only 1 patient (1 %).

Conclusion

The AWS achieves a high success rate for nasotracheal intubation with cuff inflation in patients undergoing dental and maxillofacial surgery.

The difficult airway with recommendations for management--part 1--difficult tracheal intubation encountered in an unconscious/induced patient

Background

Previously active in the mid-1990s, the Canadian Airway Focus Group (CAFG) studied the unanticipated difficult airway and made recommendations on management in a 1998 publication. The CAFG has since reconvened to examine more recent scientific literature on airway management. The Focus Group’s mandate for this article was to arrive at updated practice recommendations for management of the unconscious/induced patient in whom difficult or failed tracheal intubation is encountered.

Methods

Nineteen clinicians with backgrounds in anesthesia, emergency medicine, and intensive care joined this iteration of the CAFG. Each member was assigned topics and conducted reviews of Medline, EMBASE, and Cochrane databases. Results were presented and discussed during multiple teleconferences and two face-to-face meetings. When appropriate, evidence- or consensus-based recommendations were made together with assigned levels of evidence modelled after previously published criteria.

Conclusions

The clinician must be aware of the potential for harm to the patient that can occur with multiple attempts at tracheal intubation. This likelihood can be minimized by moving early from an unsuccessful primary intubation technique to an alternative “Plan B” technique if oxygenation by face mask or ventilation using a supraglottic device is non-problematic. Irrespective of the technique(s) used, failure to achieve successful tracheal intubation in a maximum of three attempts defines failed tracheal intubation and signals the need to engage an exit strategy. Failure to oxygenate by face mask or supraglottic device ventilation occurring in conjunction with failed tracheal intubation defines a failed oxygenation, “cannot intubate, cannot oxygenate” situation. Cricothyrotomy must then be undertaken without delay, although if not already tried, an expedited and concurrent attempt can be made to place a supraglottic device.

Randomized comparison of the Pentax AirWay Scope and Macintosh laryngoscope for tracheal intubation in patients with obstructive sleep apnoea

BACKGROUND

Patients with obstructive sleep apnoea (OSA) can often present difficulties in intubation. This study aimed to compare the efficacy of the Pentax AirWay Scope (AWS) with that of the Macintosh laryngoscope for tracheal intubation in patients with OSA.

METHODS

Forty-six patients undergoing uvulopalatopharyngoplasty were randomly allocated to tracheal intubation with either the Macintosh laryngoscope or the Pentax AWS. In all patients, intubation was performed by one of two anaesthetists experienced with both devices. The primary and secondary endpoints of this study were the intubation difficulty scale (IDS) score and success/failure and duration of the first successful intubation attempt.

RESULTS

With the Pentax AWS, tracheal intubation was successful on the first attempt in all patients whereas four patients required repeated attempts at intubation with the Macintosh laryngoscope. The IDS score was significantly lower using the Pentax AWS and glottic exposure was better (the Cormack and Lehane grade 1 in all patients vs grade 2 or higher in all patients, P<0.0001). Average duration of successful intubation was shorter (12.9 vs 29.9 s, P=0.0002), and fewer manoeuvres were needed to improve the glottic exposure (0 in all patients vs 1 or more in 16 patients, P<0.0001) with the Pentax AWS, compared with the Macintosh laryngoscope.

CONCLUSIONS

In this study of patients with OSA, tracheal intubation by experienced anaesthetists was facilitated using the Pentax AWS compared with the Macintosh laryngoscope.

The Pentax airway scope versus the Macintosh laryngoscope: Comparison of hemodynamic responses and concentrations of plasma norepinephrine to tracheal intubation

BACKGROUND

The Pentax Airway Scope (AWS) is a video laryngoscope designed to facilitate tracheal intubation with a high-resolution image. The Pentax AWS has been reported to cause less hemodynamic stress than the Macintosh laryngoscope. The aims of this study are to investigate the differences in hemodynamic responses and norepinephrine concentrations to tracheal intubation between procedures using he Pentax AWS and the Macintosh laryngoscope.

METHODS

Forty patients (American Society of Anesthesiologists class I-II, age range: 18-60 years) were randomly assigned to be intubated with either the Pentax AWS or the Macintosh laryngoscope while under general anesthesia. Routine monitoring, including invasive arterial blood pressure and bispectral index, were applied. Thiopental (4 mg/kg), fentanyl (1 µg/kg), midazolam (0.05 mg/kg), and rocuronium (0.6 mg/kg) were administered for anesthetic induction. Systolic, diastolic, and mean blood pressures and heart rates were recorded pre-intubation, immediately post-intubation (T0), and over the following 10 minutes at one minute intervals (T1, T2, T3, T4, T5…T10). Patient blood was sampled for norepinephrine concentrations pre-intubation (baseline) and post-intubation (T1). Evidence of sore throat was evaluated 30 min and 24 hr after extubation. Data were transformed to % basal and expressed as mean ± SD.

RESULTS

The systolic, diastolic, and mean blood pressure, and heart rate at T0 and T4 were significantly different between the two groups. There was no significant difference in plasma norepinephrine between the two groups. The difference in incidence of sore throat was not significant between the two groups.

CONCLUSIONS

Pentax-AWS for tracheal intubation has greater hemodynamic stability than the Macintosh blade laryngoscope.

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.

[Awake intubation using Pentax Airway Scope as an alternative to awake fiberoptic intubation in management of anticipated difficult tracheal intubation in major burn patients]

Intubating patients with facial burn is difficult to most anesthesiologists. Awake flexible fiberoptic intubation is the gold standard for management of anticipated difficult tracheal intubation. However, serious facial burn and dysmorphic syndrome can make fiberoptic intubation more difficult or impossible. We report the use of awake oral intubation using the Pentax-Airway Scope (AWS) in two major burn patients with facial injury, in whom awake fiberoptic intubation was impossible. As shown in morbidly obese patient and in patients with unstable necks, AWS could be useful to facilitate tracheal intubation in awake, facial burn patients presenting with a potentially difficult airway. Awake AWS intubation seems as a potential alternative to awake fiberoptic intubation.

A systematic review of the role of videolaryngoscopy in successful orotracheal intubation

BACKGROUND

The purpose of our study was to organize the literature regarding the efficacy of modern videolaryngoscopes in oral endotracheal intubation, then perform a quality assessment according to recommended external criteria and make recommendations for use.

METHODS

Inclusion criteria included devices with recent studies of human subjects. A total of 980 articles were returned in the initial search and 65 additional items were identified using cited references. After exclusion of articles failing to meet study criteria, 77 articles remained. Data were extracted according to the rate of successful intubation and improvement of glottic view compared with direct laryngoscopy. Studies were classified according to whether they primarily examined subjects with normal airways, possessing risk factors for difficult direct laryngoscopy, or following difficult or failed direct laryngoscopy.

RESULTS

The evidence of efficacy for videolaryngoscopy in the difficult airway is limited. What evidence exists is both randomized prospective and observational in nature, requiring a scheme that evaluates both forms and allows recommendations to be made.

CONCLUSIONS

In patients at higher risk of difficult laryngoscopy we recommend the use of the Airtraq, CTrach, GlideScope, Pentax AWS and V-MAC to achieve successful intubation. In difficult direct laryngoscopy (C&L >/= 3) we cautiously recommend the use of the Airtraq, Bonfils, Bullard, CTrach, GlideScope, and Pentax AWS, by an operator with reasonable prior experience, to achieve successful intubation when used in accordance with the ASA practice guidelines for management of the difficult airway. There is additional evidence to support the use of the Airtraq, Bonfils, CTrach, GlideScope, McGrath, and Pentax AWS following failed intubation via direct laryngoscopy to achieve successful intubation. Future investigation would benefit from precise qualification of the subjects under study, and an improvement in overall methodology to include randomization and blinding.

Observations on the assessment and optimal use of videolaryngoscopes

Due to the large number of videolaryngoscopes now available, it might be difficult for novice users to assess the various devices or use them optimally. We have collated the experiences of several airway management experts to assist in the assessment and optimal use of seven commonly used videolaryngoscopes. While all videolaryngoscopes have unique features, they can be broadly divided into those inserted via a midline approach over the tongue and those inserted laterally along the floor of the mouth. Videolaryngoscopes that are placed on the floor of the mouth displace the tongue antero-laterally and flatten the submandibular tissues. They generally require a conventional shaped bougie for tracheal intubation. Videolaryngoscopes that use the midline approach may have an in-built airway conduit for the tracheal tube or may require a 'J-shaped' stylet in the tracheal tube to negotiate the upper airway. This may cause difficulty when the tracheal tube is inserted through the glottis and the tip abuts the anterior wall of the subglottic space. Knowledge of the mechanism used by videolaryngoscopes to achieve laryngoscopy is essential for safe and successful tracheal intubation when using these devices.

A comparison of the Pentax Airway Scope™ with the Airtraq™ in an infant manikin

We compared the Pentax Airway Scope(TM) with the Airtraq(TM) optical laryngoscope in an infant manikin. Twenty-three anaesthetists randomly performed tracheal intubation: at rest, (a) with the Airway Scope and (b) with the Airtraq; and during chest compressions, (c) with the Airway Scope and (d) with the Airtraq. The success rate, modified Cormack and Lehane classification for glottic view, time taken to view the glottis, and time to place the tracheal tube were recorded. There was no difference in intubation success rate or quality of glottic view between the two devices. The median (IQR [range]) time taken to obtain a view of the glottis was 4.5 (3.7-6.4 [1.8-14.0]) s using the Airway Scope compared with 7.1 (5.5-9.6 [3.3-12.0]) s using the Airtraq (p = 0.001), and to successful placement of the tracheal tube was 8.3 (6.8-9.4 [3.7-20.7]) s using the Airway Scope compared with 11.2 (10.4-13.8 [4.9-23.7]) s using the Airtraq (p = 0.001). During chest compressions, the median (IQR [range]) time taken to view the glottis was 5.1 (4.0-7.2 [2.0-12.4]) s using the Airway Scope compared with 7.5 (5.0-13.2 [4.2-26.4]) s using the Airtraq (p = 0.006), and to successful placement of the tracheal tube was 9.5 (6.6-13.7 [4.5-16.2]) s using the Airway Scope compared with 11.7 (9.1-18.1 [6.2-37.4]) s using the Airtraq (p = 0.022). We conclude that both devices provided good quality views of the glottis and successful tracheal intubation in an infant manikin both at rest and during external chest compressions. Use of the Airway Scope resulted in a shorter time to view the glottis and perform successful tracheal intubation compared with the Airtraq.

First robotic tracheal intubations in humans using the Kepler intubation system

BACKGROUND

Intubation is one of the most important anaesthetic skills. We developed a robotic intubation system (Kepler intubation system, KIS) for oral tracheal intubation.

METHODS

In this pilot study, 12 patients were enrolled after approval of the local Ethics board and written informed consent. The KIS consists of four main components: a ThrustMaster T.Flight Hotas X joystick (Guillemot Inc., New York, NY, USA), a JACO robotic arm (Kinova Rehab, Montreal, QC, Canada), a Pentax AWS video laryngoscope (Ambu A/S, Ballerup, Denmark), and a software control system. The joystick allows simulation of the wrist or arm movements of a human operator. The success rate of intubation and intubation times were measured.

RESULTS

Eleven men and one woman aged 66 yr were included in this study. Intubation was successful in all but one patient using KIS at a total time of [median (inter-quartile range; range)] 93 (87, 109; 76, 153) s; in one patient, fogging of the video laryngoscope prevented intubation using KIS.

CONCLUSIONS

We present the first human testing of a robotic intubation system for oral tracheal intubation. The success rate was high at 91%. Future studies are needed to assess the performance and safety of such a system.

Macintosh laryngoscope vs. Pentax-AWS video laryngoscope: comparison of efficacy and cardiovascular responses to tracheal intubation in major burn patients

BACKGROUND

Patients with major burns accompanied with airway edema need more attention for airway management. Although the Pentax-AWS has an advantage in managing endotracheal intubation more easily, its usefulness cannot be assured if it does not maintain hemodynamic stability in burn patients. The aim of this study was to compare cardiovascular responses and general efficacy of the Pentax-AWS and Macintosh laryngoscopes in burn patients.

METHODS

American Society of Anesthesiologists physical status 2 or 3 adult patients with major burn injury were randomly assigned to group P (AWS, n = 50) or group M (Macintosh, n = 50). Fifty-nine patients assigned to the Macintosh group and no patient to AWS group were excluded because of failure to first intubation. Hemodynamic data at baseline, just before and after intubation as well as 3, 5 and 10 minutes after intubation and grade of sore throat were recorded in two groups. Intubation time, success rate of intubation, number of intubation attempts and the percentage of glottic opening (POGO) scores were also observed and analyzed in all patients.

RESULTS

A statistically significant increase in heart rate just after laryngoscopy was seen in group M. The success rate of the first attempt in group P (100%) was greater than with the group M (46%). POGO scores were higher in group P (97 ± 4%) than in group M (48 ± 29%)

CONCLUSIONS

The use of Pentax-AWS offers a reduced degree of heart rate elevation compared with the Macintosh laryngoscope and better intubation environments in major burn patients.