Flexible bronchoscopic intubation through a supraglottic airway device: An evaluation of consultant anaesthetist performance.

BACKGROUND: Few clinical studies investigate technical skill performance in experienced clinicians. METHODS: We undertook a prospective observational study evaluating procedural skill competence in consultant anaesthetists who performed flexible bronchoscopic intubation (FBI) under continuous ventilation through a second-generation supraglottic airway device (SAD). Airway management was recorded on video and performance evaluated independently by three external assessors. We included 100 adult patients undergoing airway management by 25 anaesthetist specialists, each performing four intubations. We used an Objective Structured Assessment of Technical Skills-inspired global rating scale as primary outcome. Further, we assessed the overall pass rate (proportion of cases where the average of assessors' evaluation for every domain scored ≥3); the progression in the global rating scale score; time to intubation; self-reported procedural confidence; and pass rate from the first to the fourth airway procedure. RESULTS: Overall median global rating scale score was 29.7 (interquartile range 26.0-32.7 [range 16.7-37.7]. At least one global rating scale domain was deemed 'not competent' (one or more domains in the evaluation was scored <3) in 30% of cases of airway management, thus the pass rate was 70% (95% CI 60%-78%). After adjusting for multiple testing, we found a statistically significant difference between the first and fourth case of airway management regarding time to intubation (p = .006), but no difference in global rating scale score (p = .018); self-reported confidence before the procedure (p = .014); or pass rate (p = .109). CONCLUSION: Consultant anaesthetists had a median global rating scale score of 29.7 when using a SAD as conduit for FBI. However, despite reporting high procedural confidence, at least one global rating scale domain was deemed 'not competent' in 30% of cases, which indicates a clear potential for improvement of skill competence among professionals.

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.

AuraGain™ versus i-gel™ for bronchoscopic intubation under continuous oxygenation: A randomised controlled trial.

INTRODUCTION: After failed mask ventilation and tracheal intubation, guidelines issued by the Difficult Airway Society recommend placing a second generation supraglottic airway device to secure oxygenation. Ultimately, a secure airway can be obtained by tracheal intubation through the supraglottic airway device using a bronchoscope. In this randomised trial, we compared the AuraGain™ with the i-gel™ as conduit for bronchoscopic intubation under continuous oxygenation performed by a group of anaesthesiologists with variable experience in a general population of patients. METHOD: We randomised one hundred patients who were equally allocated to flexible bronchoscopic intubation through the i-gel™ or the AuraGain™. In a random order, 25 anaesthesiologists each performed four intubations, two using the i-gel™ and two using the AuraGain™. Our primary outcome was 'total time for airway management'; i.e. total time from manually reaching the SAD to successful FBI confirmed at the end of the first inspiratory downstroke on the capnography curve. RESULTS: In total, 87% (95% CI, 79%-92%) of the patients were successfully intubated through the allocated supraglottic airway device. There was no difference in total time for airway management between the i-gel™ and the AuraGain™ (199 vs. 227 s, p = .076). However, there was a difference in time for placement of the i-gel™, compared to the AuraGain™, (37 vs. 54 s, p < .001). There were nine failed intubations in the AuraGain™ group compared to four in the i-gel™ group (p = .147). CONCLUSION: We found no difference in total time for airway management between using the i-gel™ and using the AuraGain™.

Intraindividual variation of the transversus abdominis plane block: an exploratory study in healthy volunteers.

INTRODUCTION: The transversus abdominis plane block is widely used in postoperative pain management after abdominal surgery. However, large interindividual variation in the cutaneous distribution area of the block has been demonstrated. The purpose of the present study was to explore the reproducibility of the block by determining the intraindividual variation when repeating the block on two separate days. METHODS: Ultrasound-guided posterior transversus abdominis plane blocks were performed in 16 healthy volunteers and repeated after at least 2 days. Cutaneous sensory block areas and distributions, thresholds for mechanical stimulation, abdominal muscle thicknesses at rest and during maximal contraction, waist circumferences and block duration times were measured on both days. Outcome measurements from the 2 days were compared using a one-sample t-test and intraclass correlation coefficients were calculated for each parameter. Agreement was evaluated visually using Bland-Altman plots. RESULTS: None of the mean values of the outcome measurements differed significantly between the 2 days. Intraclass correlation coefficient was 0.75 (moderate-to-good reliability) for lateral abdominal muscle thickness during maximal contraction, but ranges from -0.07 to 0.67 were found for all other outcome measurements (poor-to-moderate reliability). CONCLUSION: We found a moderate-to-good reproducibility for lateral abdominal muscle thickness during maximal voluntary contraction, but a moderate-to-poor reproducibility for all other block characteristics. However, the cutaneous distribution of the block was still located primarily inferior to a horizontal line through the umbilicus and lateral relative to a vertical line through the anterior superior iliac spine.

Avoidance versus use of neuromuscular blocking agents for improving conditions during tracheal intubation or direct laryngoscopy in adults and adolescents.

BACKGROUND: Tracheal intubation during induction of general anaesthesia is a vital procedure performed to secure a patient's airway. Several studies have identified difficult tracheal intubation (DTI) or failed tracheal intubation as one of the major contributors to anaesthesia-related mortality and morbidity. Use of neuromuscular blocking agents (NMBA) to facilitate tracheal intubation is a widely accepted practice. However, because of adverse effects, NMBA may be undesirable. Cohort studies have indicated that avoiding NMBA is an independent risk factor for difficult and failed tracheal intubation. However, no systematic review of randomized trials has evaluated conditions for tracheal intubation, possible adverse effects, and postoperative discomfort. OBJECTIVES: To evaluate the effects of avoiding neuromuscular blocking agents (NMBA) versus using NMBA on difficult tracheal intubation (DTI) for adults and adolescents allocated to tracheal intubation with direct laryngoscopy. To look at various outcomes, conduct subgroup and sensitivity analyses, examine the role of bias, and apply trial sequential analysis (TSA) to examine the level of available evidence for this intervention. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, BIOSIS, International Web of Science, LILACS, advanced Google, CINAHL, and the following trial registries: Current Controlled Trials; ClinicalTrials.gov; and www.centerwatch.com, up to January 2017. We checked the reference lists of included trials and reviews to look for unidentified trials. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that compared the effects of avoiding versus using NMBA in participants 14 years of age or older. DATA COLLECTION AND ANALYSIS: Two review authors extracted data independently. We conducted random-effects and fixed-effect meta-analyses and calculated risk ratios (RRs) and their 95% confidence intervals (CIs). We used published data and data obtained by contacting trial authors. To minimize the risk of systematic error, we assessed the risk of bias of included trials. To reduce the risk of random errors caused by sparse data and repetitive updating of cumulative meta-analyses, we applied TSA. MAIN RESULTS: We identified 34 RCTs with 3565 participants that met our inclusion criteria. All trials reported on conditions for tracheal intubation; seven trials with 846 participants described 'events of upper airway discomfort or injury', and 13 trials with 1308 participants reported on direct laryngoscopy. All trials used a parallel design. We identified 18 dose-finding studies that included more interventions or control groups or both. All trials except three included only American Society of Anesthesiologists (ASA) class I and II participants, 25 trials excluded participants with anticipated DTI, and obesity or overweight was an excluding factor in 13 studies. Eighteen trials used suxamethonium, and 18 trials used non-depolarizing NMBA.Trials with an overall low risk of bias reported significantly increased risk of DTI with no use of NMBA (random-effects model) (RR 13.27, 95% CI 8.19 to 21.49; P < 0.00001; 508 participants; four trials; number needed to treat for an additional harmful outcome (NNTH) = 1.9, I2 = 0%, D2 = 0%, GRADE = moderate). The TSA-adjusted CI for the RR was 1.85 to 95.04. Inclusion of all trials resulted in confirmation of results and of significantly increased risk of DTI when an NMBA was avoided (random-effects model) (RR 5.00, 95% CI 3.49 to 7.15; P < 0.00001; 3565 participants; 34 trials; NNTH = 6.3, I2 = 70%, D2 = 82%, GRADE = low). Again the cumulative z-curve crossed the TSA monitoring boundary, demonstrating harmful effects of avoiding NMBA on the proportion of DTI with minimal risk of random error. We categorized only one trial reporting on upper airway discomfort or injury as having overall low risk of bias. Inclusion of all trials revealed significant risk of upper airway discomfort or injury when an NMBA was avoided (random-effects model) (RR 1.37, 95% CI 1.09 to 1.74; P = 0.008; 846 participants; seven trials; NNTH = 9.1, I2 = 13%, GRADE = moderate). The TSA-adjusted CI for the RR was 1.00 to 1.85. None of these trials reported mortality. In terms of our secondary outcome 'difficult laryngoscopy', we categorized only one trial as having overall low risk of bias. All trials avoiding NMBA were significantly associated with difficult laryngoscopy (random-effects model) (RR 2.54, 95% CI 1.53 to 4.21; P = 0.0003; 1308 participants; 13 trials; NNTH = 25.6, I2 = 0%, D2= 0%, GRADE = low); however, TSA showed that only 6% of the information size required to detect or reject a 20% relative risk reduction (RRR) was accrued, and the trial sequential monitoring boundary was not crossed. AUTHORS' CONCLUSIONS: This review supports that use of an NMBA may create the best conditions for tracheal intubation and may reduce the risk of upper airway discomfort or injury following tracheal intubation. Study results were characterized by indirectness, heterogeneity, and high or uncertain risk of bias concerning our primary outcome describing difficult tracheal intubation. Therefore, we categorized the GRADE classification of quality of evidence as moderate to low. In light of defined outcomes of individual included trials, our primary outcomes may not reflect a situation that many clinicians consider to be an actual difficult tracheal intubation by which the patient's life or health may be threatened.

Tracheal intubation with a flexible fibreoptic scope or the McGrath videolaryngoscope in simulated difficult airway scenarios: a randomised controlled manikin study.

BACKGROUND: Flexible fibreoptic endoscopic (FFE) intubation is considered the 'gold-standard' when difficult airway management is anticipated. Several videolaryngoscopes have been developed to facilitate intubation by laryngoscopy. OBJECTIVE: The aim of the study was to compare the performance of the McGrath series 5 videolaryngoscope (McGrath videolaryngoscope) and the FFE for tracheal intubation in manikins with a simulated difficult airway, hypothesizing that the McGrath videolaryngoscope intubation would prove faster than FFE intubation. DESIGN: A randomised controlled study. SETTING: The Danish Institute for medical simulation between December 2009 and June 2010. PARTICIPANTS: Twenty-eight anaesthesia residents participating in the Danish mandatory 3-day airway management course. INTERVENTIONS: All participants received instructions and training in the use of the McGrath videolaryngoscope and FFE. The participants then performed tracheal intubation on a SimMan manikin once with the McGrath videolaryngoscope and once with the FFE in three difficult airway scenarios: (1) pharyngeal obstruction; (2) pharyngeal obstruction and cervical rigidity; (3) tongue oedema. MAIN OUTCOME MEASURES: We measured successful intubations, defined as intubation within 120  s, and time to tracheal intubation. RESULTS: The trachea was intubated within 120  s with the McGrath videolaryngoscope in 25 out of 27 (93%), 25 out of 28 (89%) and 18 out of 28 (64%) occasions compared with 11 out of 28 (40%), 11 out of 28 (40%) and 16 out of 28 (57%) with the FFE in scenarios (1), (2) and (3), respectively. Time to tracheal intubation was shorter with the McGrath videolaryngoscope in scenarios (1) and (2) than with the FFE (Wilcoxon signed rank sum test, P < 0.0001). CONCLUSION: The McGrath videolaryngoscope is a valuable device with higher success rate and a quicker performance in simulated difficult airways. In patients, videolaryngoscopy may have a role in difficult airway algorithms, but the optimal device has yet to be found.

Awake fiberoptic or awake video laryngoscopic tracheal intubation in patients with anticipated difficult airway management: a randomized clinical trial.

BACKGROUND: Awake flexible fiberoptic intubation (FFI) is the gold standard for management of anticipated difficult tracheal intubation. The purpose of this study was to compare awake FFI to awake McGrath® video laryngoscope, (MVL), (Aircraft Medical, Edinburgh, Scotland, United Kingdom) intubation in patients with an anticipated difficult intubation. The authors examined the hypothesis that MVL intubation would be faster than FFI. METHODS: Ninety-three adult patients with anticipated difficult intubation were randomly allocated to awake FFI or awake MVL, patients were given glycopyrrolate, nasal oxygen, topical lidocaine orally, and a transtracheal injection of 100 mg lidocaine. Remifentanil infusion was administered intravenously to a Ramsay sedation score of 2-4. Time to tracheal intubation was recorded by independent assessors. The authors also recorded intubation success on the first attempt, investigators' evaluation of ease of the technique, and patients reported intubation-discomfort evaluated on a visual analog scale. RESULTS: Eighty-four patients were eligible for analysis. Time to tracheal intubation was median [interquartile range, IQR] 80 s [IQR 58-117] with FFI and 62 s [IQR 55-109] with MVL (P = 0.17). Intubation success on the first attempt was 79% versus 71% for FFI and MVL, respectively. The median visual analog scale score for ease of intubation was 2 (IQR 1-4) versus 1 (IQR 1-6) for FFI and MVL, respectively. The median visual analog scale score for patients' assessment of discomfort for both techniques was 2, FFI (IQR 0-3), MVL (IQR 0-4). CONCLUSIONS: The authors found no difference in time to tracheal intubation between awake FFI and awake MVL intubation performed by experienced anesthesiologists in patients with anticipated difficult airway.