S1 guidelines on airway management: Guideline of the German Society of Anesthesiology and Intensive Care Medicine

Heidelberg Adult and Pediatric Airway Registry (HAPA-Registry)

BACKGROUND

Advanced airway management is of fundamental importance in almost all areas of anesthesiology, emergency medicine, and critical care. Securing the airway is of the utmost importance, as this is a prerequisite for the oxygenation of the human organism. The clinical relevance of airway management is particularly evident in the fact that the primary cause of significant anesthesia-related complications can be attributed to this field. The need for the systematic recording of these procedures and their complications, as well as structured training in airway management and the evaluation of outcome parameters, is, therefore, evident.

METHODS

The HAPA-registry is a prospective and monocentric observational trial at the Department of Anesthesiology, Medical Faculty Heidelberg, University of Heidelberg, Germany. All patients requiring general anesthesia with consecutive advanced airway management during a surgical procedure were included. We, therefore, planned to include approximately 9000 patients in the first period. Following successful airway management, the anesthetist completed a case report form (CRF) in person. The intention was to record airway management cases on an annual basis for a period of several months, thus ensuring that the register remains up-to-date and that airway management procedures are continuously recorded.

DISCUSSION

The aim of this study was to establish an airway registry that enables the systematic recording and evaluation of different methods of airway management. The registry can be used to monitor and evaluate the implementation of current guidelines and recommendations for action, as well as the rates of success and complications.

How China anesthesiologists document and communicate difficult airway management

BACKGROUND

According to the Chinese Society of Anesthesiology, it is recommended that patients with difficult airways be documented and notified, which will provide healthcare professionals with a direct reference when managing airways. However, compliance with this initiative remains unclear. This study was conducted to investigate the current status and need for difficult airway notification at Plastic Surgery Hospital and to explore the factors contributing to noncompliance.

METHODS

Anesthesiologists, surgeons, and patients in Plastic Surgery Hospital were administered separate questionnaires regarding notification of difficult airway management. Participants were surveyed regarding their attitudes and current practices regarding difficult airway notification. In addition, questions were asked regarding the barriers that contribute to noncompliance.

RESULTS

A total of 632 valid responses were obtained and analyzed, giving a response rate of 99.21%. 399 patients (89.46%) felt it was very important for anesthesiologists to inform them about their difficult airway, and 91.03% felt it was very important for them to receive a letter of their airway assessment. However, twenty-two anesthesiologists (64.7%) reported verbally informing less than 50% of patients about their difficult airway after surgery, and only four anesthesiologists informed all patients they encountered. Most surgeons (91.22%) and anesthesiologists (91.18%) believe that it is vital to inform patients verbally, while 114 surgeons (77.03%) and 31 anesthesiologists (91.18%) believe that it is essential to complete a difficult airway notification alert. Among the factors causing noncompliance, 17 (34.69%) believed that absence of mandatory rules, 9 (18.37%) believed that increased workload, and 8 (16.33%) believed that notification methods were lacking.

CONCLUSIONS

The compliance to difficult airway notification remains low in Plastic Surgery Hospital despite the high incidence of difficult airways. Although anesthesiologists, surgeons, and patients are strongly in favor of it. Among the barriers to compliance were the absence of a well-developed notification system and a means of notification such as an alert form for difficult airways. This may spur the anesthesiology society to publish the notification system.

Awake Tracheal Intubation: An Update

Awake tracheal intubation (ATI) remains the "gold standard" technique in securing a definitive airway in conscious, self-ventilating patients with predicted or known difficult airways and the procedure is associated with a low failure rate. Since its inception a variety of techniques to achieve ATI have emerged and there have been accompanying advancements in pharmaceuticals and technology to support the procedure. In recent years there has been a growing focus on the planning, training and human factors involved in performing the procedure. The practice of ATI, does however, remain low around 1% to 2% of all intubations despite an increase in those with head and neck pathology. ATI, therefore, presents a skill that is key for the safety of patients but may not be practised with regularity by many anesthetists. In this article we therefore aim to highlight relevant guidance, recent literature and provide an update on the practical methods fundamental for successful ATI. We also discuss the crucial aspects of a safe airway culture and how this can help to embed training and maintenance of skills.

Routine Use of Videolaryngoscopy in Airway Management

Tracheal intubation is a fundamental facet of airway management, for which the importance of achieving success at the first attempt is well recognized. Failure to do so can lead to significant morbidity and mortality if there is inadequate patient oxygenation by alternate means. The evidence supporting the benefits of a videolaryngoscope in attaining this objective is now overwhelming (in adults). This has led to its increasing recognition in international airway management guidelines and its promotion from an occasional airway rescue tool to the first-choice device during routine airway management. However, usage in clinical practice does not currently reflect the increased worldwide availability that followed the upsurge in videolaryngoscope purchasing during the coronavirus disease 2019 pandemic. There are a number of obstacles to widespread adoption, including lack of adequate training, fears over de-skilling at direct laryngoscopy, equipment and cleaning costs, and concerns over the environmental impact, among others. It is now clear that in order for patients to benefit maximally from the technology and for airway managers to fully appreciate its role in everyday practice, proper training and education are necessary. Recent research evidence has addressed some existing barriers to default usage, and the emergence of techniques such as awake videolaryngoscopy and video-assisted flexible (bronchoscopic) intubation has also increased the scope of clinical application. Future studies will likely further confirm the superiority of videolaryngoscopy over direct laryngoscopy, therefore, it is incumbent upon all airway managers (and their teams) to gain expertise in videolaryngoscopy and to use it routinely in their everyday practice..

Construction of an extubation protocol for adult tracheal intubation patients in the intensive care unit: A Delphi study

OBJECTIVE

The objective of this study was to develop an extubation practice protocol for adult intensive care unit (ICU) patients who underwent endotracheal intubation, providing theoretical guidance for clinical extubation procedures in the ICU.

METHODS

A research team was established consisting of medical, nursing, anaesthesia, and respiratory therapy professionals; the multidisciplinary team systematically searched domestic and foreign literature, summarised the best evidence, and combined it with clinical practice experience to preliminarily develop an extubation protocol for adult ICU patients who underwent endotracheal intubation. Seventeen experts in critical care medicine, intensive care nursing, clinical anaesthesia, and respiratory therapy were invited to participate in a Delphi expert consultation to screen and modify the draft protocol.

RESULTS

The response rates of the two Delphi expert enquiries were 100% and 94.1%, with expert authority coefficients of 0.94 and 0.93, respectively, and Kendall's concordance coefficients were 0.152 and 0.198, respectively, indicating statistically significant differences (p < 0.001). The final protocol included three level I indicators, 14 level II indicators, and 34 level III indicators, covering extubation evaluation, implementation, and postextubation management.

CONCLUSION

The extubation protocol for adult tracheal intubation patients in the ICU constructed in this study is scientific, practical, and reliable. This study can provide theoretical guidance for extubation in ICU patients who have undergone endotracheal intubation.

Favour the best in case of emergency cricothyroidotomy-a randomized cross-over trial on manikin focused training and simulation of common devices

Background

Performing an emergency cricothyroidotomy (EC) is extremely challenging, the devices used should be easy to handle and the selected technique reliable. However, there is still an ongoing debate concerning the most superior technique.

Methods

Three different techniques were compared using a standardized, simulated scenario regarding handling, performing, training and decision making: The scalpel-bougie technique (SBT), the surgical anatomical preparation technique (SAPT) and the Seldinger technique (ST). First, anaesthesia residents and trainees, paramedics and medical students (each group n = 50) performed a cricothyroidotomy randomly assigned with each of the three devices on a simulator manikin. The time needed for successful cricothyroidotomy was the primary endpoint. Secondary endpoints included first-attempt success rate, number of attempts and user-satisfaction. The second part of the study investigated the impact of prior hands-on training on both material selection for EC and on time to decision-making in a simulated "cannot intubate cannot ventilate" situation.

Results

The simulated scenario revealed that SBT and SAPT were significantly faster than percutaneous EC with ST (p < 0.0001). Success rate was 100% for the first attempt with SBT and SAPT. Significant differences were found with regard to user-satisfaction between individual techniques (p < 0.0001). In terms of user-friendliness, SBT was predominantly assessed as easy (87%). Prior training had a large impact regarding choice of devises (p < 0.05), and time to decision making (p = 0.05; 180 s vs. 233 s).

Conclusion

This study supports the use of a surgical technique for EC and also a regular training to create familiarity with the materials and the process itself.The trial was registered before study start on 11.11.2018 at ClinicalTrials.gov (NCT: 2018-13819) with Nicole Didion as the principal investigator.

Videolaryngoscopy use before and after the initial phases of the COVID-19 pandemic: The report of the VL-iCUE survey with responses from 96 countries

BACKGROUND

The potential benefit of videolaryngoscopy use in facilitating tracheal intubation has already been established, however its use was actively encouraged during the COVID-19 pandemic as it was likely to improve intubation success and increase the patient-operator distance.

OBJECTIVES

We sought to establish videolaryngoscopy use before and after the early phases of the pandemic, whether institutions had acquired new devices during the COVID-19 pandemic, and whether there had been teaching on the devices acquired.

DESIGN

We designed a survey with 27 questions made available via the Joint Information Scientific Committee JISC online survey platform in English, French, Spanish, Chinese, Japanese and Portuguese. This was distributed through 18 anaesthetic and airway management societies.

SETTING

The survey was open for 54 to 90 days in various countries. The first responses were logged on the databases on 28 October 2021, with all databases closed on 26 January 2022. Reminders to participate were sent at the discretion of the administering organisations.

PARTICIPANTS

All anaesthetists and airway managers who received the study were eligible to participate.

MAIN OUTCOME MEASURES

Videolaryngoscopy use before the COVID-19 pandemic and at the time of the survey.

RESULTS

We received 4392 responses from 96 countries: 944/4336 (21.7%) were from trainees. Of the 3394 consultants, 70.8% (2402/3394) indicated no change in videolaryngoscopy use, 19.9% (675/3394) increased use and 9.3% (315/3393) reduced use. Among trainees 65.5% (618/943) reported no change in videolaryngoscopy use, 27.7% (261/943) increased use and 6.8% (64/943) reduced use. Overall, videolaryngoscope use increased by 10 absolute percentage points following the pandemic.

CONCLUSIONS

Videolaryngoscopy use increased following the early phase of the COVID-19 pandemic but this was less than might have been expected.

Trauma Anesthesiology Perioperative Management Update

Anesthesia for patients with life-threatening injuries is an essential part of post-accident care. Unfortunately, there is variability in trauma anesthesia care and numerous nonstandardized methods of working with patients remain. Uncertainty exists as to when and how best to intubate trauma patients, the use of vasopressors, and the appropriate management of severe traumatic brain injury. Some physicians recommend prehospital rapid sequence intubation, whereas others use bag-mask ventilation at lower pressures with no cricoid pressure and early transport to a trauma center. Overall, the absence of uniformity in trauma anesthesia care underlines the need for continued study and dialogue to define best practices and optimize patient outcomes.

Fibreoptic intubation: a commitment to an indispensable technique

Recent evidence has shown that fibreoptic intubation is still an indispensable technique for safe management of predicted difficult airways, despite the implementation of new technologies such as videolaryngoscopy. It is therefore our obligation as anaesthesia societies and as practicing anaesthetists to offer this technique to our patients in clearly designated situations.

Awake Tracheal Intubation Is Associated with Fewer Adverse Events in Critical Care Patients than Anaesthetised Tracheal Intubation

BACKGROUND

Tracheal intubation in critical care is a high-risk procedure requiring significant expertise and airway strategy modification. We hypothesise that awake tracheal intubation is associated with a lower incidence of severe adverse events compared to standard tracheal intubation in critical care patients.

METHODS

Records were acquired for all tracheal intubations performed from 2020 to 2022 for critical care patients at a tertiary hospital. Each awake tracheal intubation case, using a videolaryngoscope with a hyperangulated blade (McGrath® MAC X-Blade), was propensity matched with two controls (1:2 ratio; standard intubation videolaryngoscopy (VL) and direct laryngoscopy (DL) undergoing general anaesthesia). The primary endpoint was the incidence of adverse events, defined as a mean arterial pressure of <55 mmHg (hypotension), SpO2 < 80% (desaturation) after sufficient preoxygenation, or peri-interventional cardiac arrest.

RESULTS

Of the 135 tracheal intubations included for analysis, 45 involved the use of an awake tracheal intubation. At least one adverse event occurred after tracheal intubation in 36/135 (27%) of patients, including awake 1/45 (2.2%; 1/1 hypotension), VL 10/45 (22%; 6/10 hypotension and 4/10 desaturation), and DL 25/45 (47%; 10/25 hypotension, 12/25 desaturation, and 3/25 cardiac arrest; p < 0.0001).

CONCLUSIONS

In this retrospective observational study of intubation practices in critical care patients, awake tracheal intubation was associated with a lower incidence of severe adverse events than anaesthetised tracheal intubation.

A prospective observational study of recall of discomfort on tracheal extubation after general anaesthesia

Background

Tracheal extubation is a critical stage in the management of general anaesthesia during which serious complications may occur. Immediately before extubation, patients often exhibit signs that suggest that they are awake and experiencing discomfort. There is concern that patients may retain such memories of the extubation process. However, previous studies have not examined patient recall of extubation in detail. We therefore investigated the frequency of recall of discomfort during extubation, as well as first orientation to place, and other recollections upon emerging from general anaesthesia.

Methods

In a prospective observational study, 818 patients were interviewed during routine post-anaesthesia rounds on the day after general anaesthesia. The primary outcome was the proportion of patients recalling discomfort during extubation. The secondary outcome was the location of orientation to place upon emerging from general anaesthesia.

Results

Recall of discomfort during extubation was uncommon, at 1.1% (n=9; 95% confidence interval [CI]: 0.5-2.1%). Only 3.1% of patients recalled the extubation process at all (n=25; 95% CI: 2.0-4.5%). The first orientation to place was most commonly in transit to a ward, in 41% of cases (n=337; 95% CI: 38-45%).

Conclusions

Recall of discomfort during extubation appears to be rare, and the great majority of patients may not retain any memory of the extubation process. This information may be used to reassure patients and guide extubation practices for anaesthetists.

Clinical trial registration

UMIN Clinical Trials Registry (UMIN000046136).

A multicentre randomised controlled trial of the McGrath Mac videolaryngoscope versus conventional laryngoscopy

Before completion of this study, there was insufficient evidence demonstrating the superiority of videolaryngoscopy compared with direct laryngoscopy for elective tracheal intubation. We hypothesised that using videolaryngoscopy for routine tracheal intubation would result in higher first-pass tracheal intubation success compared with direct laryngoscopy. In this multicentre randomised trial, 2092 adult patients without predicted difficult airway requiring tracheal intubation for elective surgery were allocated randomly to either videolaryngoscopy with a Macintosh blade (McGrath) or direct laryngoscopy. First-pass tracheal intubation success was higher with the McGrath (987/1053, 94%), compared with direct laryngoscopy (848/1039, 82%); absolute risk reduction (95%CI) was 12.1% (10.9-13.6%). This resulted in a relative risk (95%CI) of unsuccessful tracheal intubation at first attempt of 0.34 (0.26-0.45; p < 0.001) for McGrath compared with direct laryngoscopy. Cormack and Lehane grade ≥ 3 was observed more frequently with direct laryngoscopy (84/1039, 8%) compared with McGrath (8/1053, 0.7%; p < 0.001) No significant difference in tracheal intubation-associated adverse events was observed between groups. This study demonstrates that using McGrath videolaryngoscopy compared with direct laryngoscopy improves first-pass tracheal intubation success in patients having elective surgery. Practitioners may consider using this device as first choice for tracheal intubation.

Impact of direct laryngoscopy vs. videolaryngoscopy on signal quality of recurrent laryngeal nerve monitoring in thyroid surgery: a randomised parallel group trial

In thyroid surgery, intra-operative neuromonitoring signals of the recurrent laryngeal nerve can be detected by surface electrodes on a tracheal tube positioned at the vocal fold level. The incidence of difficult tracheal intubation in patients undergoing thyroidectomy for nodular goitre ranges from 5.3% to 20.5%. The aim of this study was to compare videolaryngoscopy with conventional direct laryngoscopy as methods for proper placement of the surface electrode to prevent insufficient intra-operative nerve signal quality. In this prospective randomised trial, adult patients requiring tracheal intubation during thyroid surgery were randomly allocated to two groups of C-MAC^® (Macintosh style blade) videolaryngoscope or direct laryngoscopy using the Macintosh laryngoscope. Primary outcome was the incidence of insufficient signal electromyogram amplitude level (< 500 μV) after successful tracheal intubation. A total of 260 (130 per group) participants were analysed. An insufficient signal was more frequent with direct laryngoscopy (35/130, 27%), compared with C-MAC (12/130, 9%, p < 0.001). First-pass tracheal intubation success rate was lower with direct laryngoscopy (86/130 (66%)) compared with the C-MAC (125/130 (96%)) (p < 0.0001). Cormack and Lehane grade ≥ 3 was observed more frequently with direct laryngoscopy (16/130 (12%)), compared with the C-MAC (0/130, (0%)) (p < 0.0001). The results suggest that videolaryngoscopy has an impact on the quality of the initial intra-operative neuromonitoring signal in patients undergoing thyroid surgery, and this technique can provide optimised surface electrode positioning.

The use of video laryngoscopy outside the operating room: A systematic review

This study aimed to describe how video laryngoscopy is used outside the operating room within the hospital setting. Specifically, we aimed to summarise the evidence for the use of video laryngoscopy outside the operating room, and detail how it appears in current clinical practice guidelines. A literature search was conducted across two databases (MEDLINE and Embase), and all articles underwent screening for relevance to our aims and pre-determined exclusion criteria. Our results include 14 clinical practice guidelines, 12 interventional studies, 38 observational studies. Our results show that video laryngoscopy is likely to improve glottic view and decrease the incidence of oesophageal intubations; however, it remains unclear as to how this contributes to first-pass success, overall intubation success and clinical outcomes such as mortality outside the operating room. Furthermore, our results indicate that the appearance of video laryngoscopy in clinical practice guidelines has increased in recent years, and particularly through the COVID-19 pandemic. Current COVID-19 airway management guidelines unanimously introduce video laryngoscopy as a first-line (rather than rescue) device.

Video Laryngoscopy Using King Vision™ aBlade™ and Direct Laryngoscopy in Paediatric Airway Management: A Randomized Controlled Study about Device Learning by Anaesthesia Residents

Background: Airway management in children is challenging due to anatomical and physiological differences. This randomized trial investigates whether anaesthesia residents can intubate the paediatric trachea more quickly and with a higher success rate using the King Vision™ Paediatric aBlade™ video laryngoscope (KVL) compared to conventional direct laryngoscopy (DL). Methods: Eleven anaesthesia residents (mean age: 31 years, mean training status 47 months) were each asked to perform intubations with the KVL and DL in paediatric patients. The primary outcome was the first-attempt success rate. Secondary outcomes were the time to best view (TTBV), time to placement of the tracheal tube (TTP), time to ventilation (TTV), and participant-reported ease of use on a Likert scale. Results: 105 intubations with the KVL and 106 DL were performed by the residents. The success rate on the first attempt with the KVL was 81%, and the success rate on the first attempt within a given time limit of 30 s was 45%, which was lower than with DL (93% and 77% with time limit, p < 0.01). The median TTBV [IQR] on the first attempt with KVL was 7 [5−10] s, the median TTP was 28 [19−44] s, and the median TTV was 51 [39−66] s. DL-mediated intubation was significantly faster (TTP: 17 [13−23] s; p < 0.0001 and TTV: 34 [28−44] s; p < 0.001). Application of the KVL was rated as difficult or very difficult by 60% of the residents (DL: 5%). Conclusion: In contrast to promising data on the paediatric training manikin, residents took longer to intubate the airway in children with the KVL and were less successful compared to the DL. Therefore, the KVL should not be recommended for learning paediatric intubation by residents.

Big data: Airway management at a university hospital over 16 years; a retrospective analysis

Purpose

Little is known about the current practice of airway management in Germany and its development over the last decades. The present study was, therefore, designed to answer the following questions. Which airway management procedures have been performed over the last 16 years and how has the frequency of these procedures changed over time? Is there a relationship between patient characteristics or surgical specialisation and the type of airway management performed?

Methods

In the present study, we used our in-house data acquisition and accounting system to retrospectively analyse airway management data for all patients who underwent a surgical or medical procedure with anaesthesiological care at our tertiary care facility over the past 16 years. 340,748 airway management procedures were analysed by type of procedure, medical/surgical specialty, and type of device used. Logistic regression was used to identify trends over time.

Results

Oral intubation was the most common technique over 16 years (65.7%), followed by supraglottic airway devices (18.1%), nasal intubation (7.5%), mask ventilation (1.6%), tracheal cannula (1.3%), double lumen tube (0.7%), and jet ventilation (0.6%). On average, the odds ratio of using supraglottic airway devices increased by 17.0% per year (OR per year = 1.072, 95% CI = 1.071–1.088) while oral intubation rates decreased. In 2005, supraglottic airway devices were used in about 10% of all airway management procedures. Until 2020, this proportion steadily increased by 27%. Frequency of oral intubation on the other hand decreased and was about 75% in 2005 and 53% in 2020.

Over time, second-generation supraglottic airway devices were used more frequently than first-generation supraglottic airway devices. While second-generation devices made up about 9% of all supraglottic airway devices in 2010, in 2020 they represented a proportion of 82%.

The use of fibreoptic intubation increased over time in otorhinolaryngology and dental, oral, and maxillofacial surgery, but showed no significant trends over the entire 16-year period.

Conclusion

Our data represent the first large-scale evaluation of airway management procedures over a long time. There was a significant upward trend in the use of supraglottic airway devices, with an increase in the use of second-generation masks while a decrease in oral intubations was observed.

Rocuronium versus saline for effective facemask ventilation during anesthesia induction: a double-blinded randomized placebo-controlled trial

Background

Mask ventilation progressively improves after loss of consciousness during anesthesia induction possibly due to progression of muscle paralysis. This double-blinded randomized placebo-controlled study aimed to test a hypothesis that muscle paralysis improves mask ventilation during anesthesia induction.

Methods

Forty-four adults patients including moderate to severe obstructive sleep apnea undergoing scheduled surgeries under elective general anesthesia participated in this study. Randomly-determined test drug either rocuronium or saline was blinded to the patient and anesthesia provider. One-handed mask ventilation with an anesthesia ventilator providing a constant driving pressure and respiratory rate (15 breaths per minute) was performed during anesthesia induction, and changes of capnogram waveform and tidal volume were assessed for one minute. The needed breaths for achieving plateaued-capnogram (primary variable) within 15 consecutive breaths were compared between the test drugs.

Results

Measurements were successful in 38 participants. Twenty-one and seventeen patients were allocated into saline and rocuronium respectively. The number of breaths achieving plateaued capnogram did not differ between the saline (95% C.I.: 6.2 to 12.8 breaths) and rocuronium groups (95% C.I.: 5.6 to 12.7 breaths) (p = 0.779). Mean tidal volume changes from breath 1 was significantly greater in rocuronium group than saline group (95% C.I.: 0.56 to 0.99 versus 3.51 to 4.53 ml kg-IBW−1, p = 0.006). Significantly more patients in rocuronium group (94%) achieved tidal volume greater than 5 mg kg-ideal body weight−1 within one minute than those in saline group (62%) (p = 0.026). Presence of obstructive sleep apnea did not affect effectiveness of rocuronium for improvement of tidal volume during one-handed mask ventilation.

Conclusions

Use of rocuronium facilitates tidal volume improvement during one-handed mask ventilation even in patients with moderate to severe obstructive sleep apnea.

Trial registration

The clinical trial was registered at (05/12/2013, UMIN000012495): https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000014515

Evaluation of gender differences in postoperative sore throat and hoarseness following the use of Ambu AuraGain laryngeal mask: the randomised controlled LadyLAMA trial study protocol

INTRODUCTION

Postoperative sore throat (POST) is a comparatively minor but very common side effect of general anaesthesia with a supraglottic airway device. The patient considers these side effects a mirror of the quality of anaesthesia. The aims of this study are to evaluate gender-specific differences in the incidence of POST and to assess whether the effects of known risk factors vary between genders.

METHODS AND ANALYSIS

The LadyLAMA trial is a single-centre, patient-blinded, randomised controlled trial. Consecutive patients requiring ophthalmological surgery under general anaesthesia with a second generation Ambu AuraGain laryngeal mask are randomly allocated to either cuff pressure of 45 cmH2O or cuff pressure of 60 cmH2O. We estimate the difference in POST between the genders at 20% and we hypothesised that a reduction of cuff pressure would reduce POST by 10%. A total of 800 patients will be recruited, with each subgroup including 200 patients to achieve 80% power for detecting a difference at the 5% significance level. Primary endpoints are gender differences in the incidence of POST within 24 hours postoperatively, as well as comparison of cuff pressure 45 cmH2O to 60 cmH2O with respect to POST. The main secondary objective is the effect of cuff pressure on POST stratified by gender. Further secondary endpoints are gender-specific differences in POST and hoarseness in postanaesthesia care unit (PACU) at 48 and 72 hours (or until freedom of discomfort). The parameter cuff pressure serves as key-secondary endpoint.

ETHICS AND DISSEMINATION

The project is approved by the local ethics committee of the Medical Association of the Rhineland Palatine state (Nr. 2021-15835). The results of this study will be made available in the form of manuscripts for publication and presentations at national and international meetings.

TRIAL REGISTRATION NUMBER

NCT04915534.

Anaesthesia protocol evaluation of the videolaryngoscopy with the McGrath MAC and direct laryngoscopy for tracheal intubation in 1000 patients undergoing rapid sequence induction: the randomised multicentre LARA trial study protocol

INTRODUCTION

Rapid sequence induction of anaesthesia is indicated in patients with an increased risk of pulmonary aspiration. The main objective of the technique is to reduce the critical time period between loss of airway protective reflexes and rapid inflation of the cuff of the endotracheal tube to minimise the chance of aspiration of gastric contents. The COVID-19 pandemic has reinforced the importance of first-pass intubation success to ensure patient and healthcare worker safety. The aim of this study is to compare the first-pass intubation success rate (FPS) using the videolaryngoscopy compared with conventional direct laryngoscopy in surgical patients with a high risk of pulmonary aspiration.

METHODS AND ANALYSIS

The LARA trial is a multicentre, patient-blinded, randomised controlled trial. Consecutive patients requiring tracheal intubation are randomly allocated to either the McGrath MAC videolaryngoscope or direct laryngoscopy using the Macintosh laryngoscope. The expected rate of FPS is 92% in the McGrath group and 82% in the Macintosh group. Each group must include a total of 500 patients to achieve 90% power for detecting a difference at the 5% significance level. Successful intubation with the FPS is the primary endpoint. The secondary endpoints are the time to intubation, the number of intubation attempts, the necessity of airway management alternatives, the visualisation of the glottis using the Cormack and Lehane Score and the Percentage Of Glottic Opening Score and definite adverse events.

ETHICS AND DISSEMINATION

The project is approved by the local ethics committee of the Medical Association of the Rhineland Palatine state (registration number: 2020-15502) and medical ethics committee of the University of Freiburg (registration number: 21-1303). The results of this study will be made available in form of manuscripts for publication and presentations at national and international meetings.

TRIAL REGISTRATION

NCT04794764.

Anaesthetic protocol for paediatric glaucoma examinations: the prospective EyeBIS Study protocol

INTRODUCTION

Neonates and young infants with diagnosed or highly suspected glaucoma require an examination under anaesthesia to achieve accurate intraocular pressure (IOP) measurements, since crying or squinting of the eyes may increase IOP and lead to falsely high values. IOP considerably depends on perioperative variables such as haemodynamic factors, anaesthetics, depth of anaesthesia and airway management. The aim of this paper is to report the design and baseline characteristics of EyeBIS, which is a study to develop a standardised anaesthetic protocol for the measurement of IOP under anaesthesia in childhood glaucoma, by investigating the link between the magnitude of IOP and depth of anaesthesia.

METHODS AND ANALYSIS

This is a single-centre, prospective cohort study in 100 children with diagnosed or highly suspected glaucoma all undergoing ophthalmological examination under general anaesthesia. 20 children, who undergo general anaesthesia for other reasons, are included as controls. The primary outcome measure is the establishment of a standardised anaesthetic protocol for IOP measurement in childhood glaucoma by assessing the relationship between IOP and depth of anaesthesia (calculated as an electroencephalography variable, the bispectral index), with special emphasis on airway management and haemodynamic parameters. The dependence of IOP under anaesthesia on airway management and haemodynamic parameters will be described, using a mixed linear model. Restricting the model to patients with healthy eyes will allow to determine a 95% reference region, in which 95% of the measurement values of patients with healthy eyes can be expected.

ETHICS AND DISSEMINATION

The study has been approved by the local ethics committee of the Medical Association of Rhineland-Palatine (Ethik-Kommisssion der Landesaerztekammer Rheinland-Pfalz), Germany (approval number: 2019-14207). This work will be disseminated by publication of peer-reviewed manuscripts, presentation in abstract form at national and international scientific meetings and data sharing with other investigators.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT03972852).

[Noninvasive evaluation of airways prior to sedation or anesthesia : An update within the framework of the revision of the German S1 guidelines on airway management 2015 of the German Society for Anesthesiology and Intensive Care Medicine]

As a single and reliable parameter for prediction of the difficult airway is missing, the specialist societies for anesthesiology recommend the use of scores that combine the individual parameters. Contemporary scores include head-neck mobility, mouth opening and anatomical distances. Their training and correct performance are essential. For a broad acceptance the performance has to be easy and fast. In addition, before anesthesia a check must be made for pathological alterations (e.g. tumors) in the head and neck region and the patient history must be thoroughly determined. If the patient reports difficulties with securing the airway in the past, these are likely to occur again if they have not been surgically resolved. This includes an accurate documentation of the airway and knowledge of the in-house standard operating procedure on unexpected difficult airways as well as local equipment. Preparation causes work but may save lives.

Rapid sequence induction: where did the consensus go?

Background

Rapid Sequence Induction (RSI) was introduced to minimise the risk of aspiration of gastric contents during emergency tracheal intubation. It consisted of induction with the use of thiopentone and suxamethonium with the application of cricoid pressure.

This narrative review describes how traditional RSI has been modified in the UK and elsewhere, aiming to deliver safe and effective emergency anaesthesia outside the operating room environment. Most of the key aspects of traditional RSI – training, technique, drugs and equipment have been challenged and often significantly changed since the procedure was first described. Alterations have been made to improve the safety and quality of the intervention while retaining the principles of rapidly securing a definitive airway and avoiding gastric aspiration. RSI is no longer achieved by an anaesthetist alone and can be delivered safely in a variety of settings, including in the pre-hospital environment.

Conclusion

The conduct of RSI in current emergency practice is far removed from the original descriptions of the procedure. Despite this, the principles – rapid delivery of a definitive airway and avoiding aspiration, are still highly relevant and the indications for RSI remain relatively unchanged.

Creation of an artificial intelligence model for intubation difficulty classification by deep learning (convolutional neural network) using face images: an observational study

Background

Tracheal intubation is the gold standard for securing the airway, and it is not uncommon to encounter intubation difficulties in intensive care units and emergency rooms. Currently, there is a need for an objective measure to assess intubation difficulties in emergency situations by physicians, residents, and paramedics who are unfamiliar with tracheal intubation. Artificial intelligence (AI) is currently used in medical imaging owing to advanced performance. We aimed to create an AI model to classify intubation difficulties from the patient’s facial image using a convolutional neural network (CNN), which links the facial image with the actual difficulty of intubation.

Methods

Patients scheduled for surgery at Yamagata University Hospital between April and August 2020 were enrolled. Patients who underwent surgery with altered facial appearance, surgery with altered range of motion in the neck, or intubation performed by a physician with less than 3 years of anesthesia experience were excluded. Sixteen different facial images were obtained from the patients since the day after surgery. All images were judged as “Easy”/“Difficult” by an anesthesiologist, and an AI classification model was created using deep learning by linking the patient’s facial image and the intubation difficulty. Receiver operating characteristic curves of actual intubation difficulty and AI model were developed, and sensitivity, specificity, and area under the curve (AUC) were calculated; median AUC was used as the result. Class activation heat maps were used to visualize how the AI model classifies intubation difficulties.

Results

The best AI model for classifying intubation difficulties from 16 different images was generated in the supine-side-closed mouth-base position. The accuracy was 80.5%; sensitivity, 81.8%; specificity, 83.3%; AUC, 0.864; and 95% confidence interval, [0.731-0.969], indicating that the class activation heat map was concentrated around the neck regardless of the background; the AI model recognized facial contours and identified intubation difficulties.

Conclusion

This is the first study to apply deep learning (CNN) to classify intubation difficulties using an AI model. We could create an AI model with an AUC of 0.864. Our AI model may be useful for tracheal intubation performed by inexperienced medical staff in emergency situations or under general anesthesia.

Rapid sequence induction: An international survey

BACKGROUND

Rapid sequence induction (RSI) is a standard procedure, which should be implemented in all patients with a risk of aspiration/regurgitation during anaesthesia induction.

OBJECTIVE

The primary aim was to evaluate clinical practice in RSI, both in adult and paediatric populations.

DESIGN

Online survey.

SETTINGS

A total of 56 countries.

PARTICIPANTS

Members of the European Society of Anaesthesiology.

MAIN OUTCOME MEASURES

The aim was to identify and describe the actual clinical practice of RSI related to general anaesthesia.

RESULTS

From the 1921 respondents, 76.5% (n=1469) were qualified anaesthesiologists. When anaesthetising adults, the majority (61.7%, n=1081) of the respondents preoxygenated patients with 100% O₂ for 3 min and 65.9% (n=1155) administered opioids during RSI. The Sellick manoeuvre was used by 38.5% (n=675) and was not used by 37.4% (n=656) of respondents. First-line medications for a haemodynamically stable adult patient were propofol (90.6%, n=1571) and suxamethonium (56.0%, n=932). Manual ventilation (inspiratory pressure <12 cmH₂O) was used in 35.5% (n=622) of respondents. In the majority of paediatric patients, 3 min of preoxygenation (56.6%, n=817) and opioids (54.9%, n=797) were administered. The Sellick manoeuvre and manual ventilation (inspiratory pressure <12 cmH₂O) in children were used by 23.5% (n=340) and 35.9% (n=517) of respondents, respectively. First-line induction drugs for a haemodynamically stable child were propofol (82.8%, n=1153) and rocuronium (54.7%, n=741).

CONCLUSION

We found significant heterogeneity in the daily clinical practice of RSI. For patient safety, our findings emphasise the need for international RSI guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03694860

Analysis of tracheal intubation in out-of-hospital helicopter emergency medicine recorded by video laryngoscopy

Background

Tracheal intubation remains the gold standard of airway management in emergency medicine and maximizing safety, intubation success, and especially first-pass intubation success (FPS) in these situations is imperative.

Methods

We conducted a prospective observational study on all 12 helicopter emergency medical service (HEMS) bases of the Swiss Air Rescue, between February 15, 2018, and February 14, 2019. All 428 patients on whom out-of-hospital advanced airway management was performed by the HEMS crew were included. The C-MAC video laryngoscope was used as the primary device for tracheal intubation. Intubation procedures were recorded by the video laryngoscope and precise time points were recorded to verify the time necessary for each attempt and the overall procedure time until successful intubation. The videos were further analysed for problems and complications during airway management by an independent reviewer. Additionally, a questionnaire about the intubation procedure, basic characteristics of the patient, circumstances, environmental factors, and the provider’s level of experience in airway management was filled out. Main outcome measures were FPS of tracheal intubation, overall success rate, overall intubation time, problems and complications of video laryngoscopy.

Results

FPS rate was 87.6% and overall success rate 98.6%. Success rates, overall time to intubation, and subjective difficulty were not associated to the providers’ expertise in airway management. In patients undergoing CPR FPS was 84.8%, in trauma patients 86.4% and in non-trauma patients 93.3%. FPS in patients with difficult airway characteristics, facial trauma/burns or obesity ranges between 87 and 89%. Performing airway management indoors or inside an ambulance resulted in a significantly higher FPS of 91.1% compared to outdoor locations (p < 0.001). Direct solar irradiation on the screen, fogging of the lens, and blood on the camera significantly impaired FPS. Several issues for further improvements in the use of video laryngoscopy in the out-of-hospital setting and for quality control in airway management were identified.

Conclusion

Airway management using the C-MAC video laryngoscope with Macintosh blade in a group of operators with mixed experience showed high FPS and overall rates of intubation success. Video recording emergency intubations may improve education and quality control.

Current Recommendations for Airway Management Techniques in COVID-19 Patients without Respiratory Failure Undergoing General Anaesthesia: A Nonsystematic Literature Review

Summary Background

Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first emerged, many articles have been published on airway management for coronavirus disease 2019 (COVID-19) patients. However, there is a lack of clear and concise conceptual framework for working with infected patients without respiratory failure undergoing general anaesthesia compared to noninfected patients. The aim of this article is to review current literature data on new challenges for anaesthesia providers, compare standard airway management techniques protocols with new data, and discuss optimisation potential.

Materials and methods

Literature search was performed in Google Scholar and PubMed databases using these keywords and their combinations: anaesthesia, preoxygenation, airway management, difficult airway, SARS-CoV-2, COVID-19. The following nonsystematic review is based on a comprehensive literature search of available data, wherein 41 articles were chosen for detailed analysis. Summarised and analysed data are presented in the article.

Results

SARS-CoV-2 has unique implications for airway management techniques in patients without respiratory failure undergoing general anesthesia. Main differences with the standard practice include: institutional preparedness, team composition principles, necessary skills, equipment, drugs, intubation and extubation strategies. Failed or difficult intubation is managed with predominance of emergency front of neck access (FONA) due to increased aerosol generation.

Conclusions

Airway management techniques in COVID-19 patients without respiratory failure are more challenging than in noninfected patients undergoing general anaesthesia. Safe, accurate and swift actions avoid unnecessary time delay ensuring the best care for patients, and reduce risk of contamination for staff. Appropriate airway strategy, communication, minimisation of time for aerosol generating procedures and ramped-up position aid to achieve these goals. During the pandemic, updated available literature data may change clinical practice as new evidence emerges.

Subglottic stenosis imitating the carina - a case report of airway mimicry

We present a case of awake tracheal intubation with flexible bronchoscopy which resulted in incorrect tracheal tube placement. The presence of a stenotic subglottic lesion with an appearance similar to the carina led to the tube being positioned with only the tip within the trachea whilst the cuff was located between the vocal cords. A capnography trace was identified before induction of anaesthesia; however, visual confirmation of the carina was undertaken in a rushed manner due to the patient becoming agitated. Once the incorrect tracheal tube placement was identified, the decision was made to wake the patient. Thereafter, a more experienced operator successfully performed awake tracheal intubation with flexible bronchoscopy using a smaller tracheal tube, which easily passed through the subglottic stenosis. This report emphasises the importance of performing the ‘two‐point check’ every time awake tracheal intubation is undertaken: to confirm correct tube placement, both a capnography trace and view of the tracheal lumen including the carina and main bronchi is required. This must be properly performed before induction of anaesthesia; safety should not be compromised by a stressful environment or time pressure.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 1. Difficult airway management encountered in an unconscious patient

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the literature on airway management has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This first of two articles addresses difficulty encountered with airway management in an unconscious patient.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians, were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence was lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Most studies comparing video laryngoscopy (VL) with direct laryngoscopy indicate a higher first attempt and overall success rate with VL, and lower complication rates. Thus, resources allowing, the CAFG now recommends use of VL with appropriately selected blade type to facilitate all tracheal intubations. If a first attempt at tracheal intubation or supraglottic airway (SGA) placement is unsuccessful, further attempts can be made as long as patient ventilation and oxygenation is maintained. Nevertheless, total attempts should be limited (to three or fewer) before declaring failure and pausing to consider "exit strategy" options. For failed intubation, exit strategy options in the still-oxygenated patient include awakening (if feasible), temporizing with an SGA, a single further attempt at tracheal intubation using a different technique, or front-of-neck airway access (FONA). Failure of tracheal intubation, face-mask ventilation, and SGA ventilation together with current or imminent hypoxemia defines a "cannot ventilate, cannot oxygenate" emergency. Neuromuscular blockade should be confirmed or established, and a single final attempt at face-mask ventilation, SGA placement, or tracheal intubation with hyper-angulated blade VL can be made, if it had not already been attempted. If ventilation remains impossible, emergency FONA should occur without delay using a scalpel-bougie-tube technique (in the adult patient). The CAFG recommends all institutions designate an individual as "airway lead" to help institute difficult airway protocols, ensure adequate training and equipment, and help with airway-related quality reviews.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 2. Planning and implementing safe management of the patient with an anticipated difficult airway

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the published airway management literature has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This second of two articles addresses airway evaluation, decision-making, and safe implementation of an airway management strategy when difficulty is anticipated.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence is lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Prior to airway management, a documented strategy should be formulated for every patient, based on airway evaluation. Bedside examination should seek predictors of difficulty with face-mask ventilation (FMV), tracheal intubation using video- or direct laryngoscopy (VL or DL), supraglottic airway use, as well as emergency front of neck airway access. Patient physiology and contextual issues should also be assessed. Predicted difficulty should prompt careful decision-making on how most safely to proceed with airway management. Awake tracheal intubation may provide an extra margin of safety when impossible VL or DL is predicted, when difficulty is predicted with more than one mode of airway management (e.g., tracheal intubation and FMV), or when predicted difficulty coincides with significant physiologic or contextual issues. If managing the patient after the induction of general anesthesia despite predicted difficulty, team briefing should include triggers for moving from one technique to the next, expert assistance should be sourced, and required equipment should be present. Unanticipated difficulty with airway management can always occur, so the airway manager should have a strategy for difficulty occurring in every patient, and the institution must make difficult airway equipment readily available. Tracheal extubation of the at-risk patient must also be carefully planned, including assessment of the patient's tolerance for withdrawal of airway support and whether re-intubation might be difficult.

Project for Universal Management of Airways - part 1: concept and methods

Multiple professional groups and societies worldwide have produced airway management guidelines. These are typically targeted at the process of tracheal intubation by a particular provider group in a restricted category of patients and reflect practice preferences in a particular geographical region. The existence of multiple distinct guidelines for some (but not other) closely related circumstances, increases complexity and may obscure the underlying principles that are common to all of them. This has the potential to increase cognitive load; promote the grouping of ideas in silos; impair teamwork; and ultimately compromise patient care. Development of a single set of airway management guidelines that can be applied across and beyond these domains may improve implementation; promote standardisation; and facilitate collaboration between airway practitioners from diverse backgrounds. A global multidisciplinary group of both airway operators and assistants was assembled. Over a 3-year period, a review of the existing airway guidelines and multiple reviews of the primary literature were combined with a structured process for determining expert consensus. Any discrepancies between these were analysed and reconciled. Where evidence in the literature was lacking, recommendations were made by expert consensus. Using the above process, a set of evidence-based airway management guidelines was developed in consultation with airway practitioners from a broad spectrum of disciplines and geographical locations. While consistent with the recommendations of the existing English language guidelines, these universal guidelines also incorporate the most recent concepts in airway management as well as statements on areas not widely addressed by the existing guidelines. The recommendations will be published in four parts that respectively address: airway evaluation; airway strategy; airway rescue and communication of airway outcomes. Together, these universal guidelines will provide a single, comprehensive approach to airway management that can be consistently applied by airway practitioners globally, independent of their clinical background or the circumstances in which airway management occurs.

Aligning difficult airway guidelines with the anesthetic COVID-19 guidelines to develop a COVID-19 difficult airway strategy: a narrative review

The coronavirus disease 2019 (COVID-19) pandemic is caused by a coronavirus that is transmitted primarily via aerosol, droplets or direct contact. This may place anesthetists at higher risk of infection due to their frequent involvement in aerosol-generating airway interventions. Many anesthethetic COVID-19 guidelines have emerged, whose underlying management principles include minimizing aerosol contamination and protecting healthcare workers. These guidelines originate from Australia and New Zealand, Canada, China, India, Italy, Korea, Singapore, the United States and the United Kingdom. Hospitalized COVID-19 patients may require airway interventions, and difficult tracheal intubation secondary to laryngeal edema has been reported. Pre-pandemic difficult airway guidelines include those from Canada, France, Germany, India, Japan, Scandinavia, the United States and the United Kingdom. These difficult airway guidelines require modifications in order to align with the principles of the anesthetic COVID-19 guidelines. In turn, most of the anesthetic COVID-19 guidelines do not, or only briefly, discuss an airway strategy after failed tracheal intubation. Our article identifies and compares pre-pandemic difficult airway guidelines with the recent anesthetic COVID-19 guidelines. We combine the principles from both sets of guidelines and explain the necessary modifications to the airway guidelines, to form a failed tracheal intubation airway strategy in the COVID-19 patient. Valuing, and a greater understanding of, these differences and modifications may lead to greater adherence to the new COVID-19 guidelines.

Learning curve and performance in simulated difficult airway for the novel C-MAC® video-stylet and C-MAC® Macintosh video laryngoscope: A prospective randomized manikin trial

Difficult airways can be managed with a range of devices, with video laryngoscopes (VLs) being the most common. The C-MAC® Video-Stylet (VS; Karl-Storz Germany), a hybrid between a flexible and a rigid intubation endoscope, has been recently introduced. The aim of this study is to investigate the performance of the VS compared to a VL (C-MAC Macintosh blade, Karl-Storz Germany) with regards to the learning curve for each device and its ability to manage a simulated difficult airway manikin. This is a single-center, prospective, randomized, crossover study involving twenty-one anesthesia residents performing intubations on a Bill 1™ (VBM, Germany) airway manikin model. After a standardized introduction, six randomized attempts with VL and VS were performed on the manikin. This was followed by intubation in a simulated difficult airway (cervical collar and inflated tongue) with both devices in a randomized fashion. The primary end-point of this study was the total time to intubation. All continuous variables were expressed as the median [interquartile range] and analyzed using the Mann-Whitney U test. A 2-way ANOVA with Bonferroni's post hoc test was used to compare both devices at each trial. All reported p values are two sided. The median total time to intubation on a simulated difficult airway was faster with the VS compared to VL (17 [13.5-25] sec vs 23 [18.5-26.5] sec, respectively; 95% CI; P = 0.031). Additionally, on a normal airway manikin, the VS has a comparable learning curve to the VL. In this manikin-based study, the novel VS was comparable to the VL in terms of learning curve in a normal airway. In a simulated difficult airway, the total time to intubation, though likely not clinically relevant, was faster with the VS to the VL. However, given the above findings, this study justifies further human clinical trials with the VS to see if similar benefits-faster time to intubation and similar learning curve to VL-are replicated clinically.

Flexible fibreoptic intubation in swine - improvement for resident training and animal safety alike

Background

Efficient airway management to facilitate tracheal intubation encompasses essential skills in anaesthesiologic and intensive care. The application of flexible fibreoptic intubation in patients with difficult airways has been identified as the recommended method in various international guidelines. However, providing the opportunity to adequately train residents can be challenging. Using large animals for practice during ongoing studies could help to improve this situation, but there is no recent data on fibreoptic intubation in swine available.

Methods

Thirty male German landrace pigs were anesthetized, instrumented and randomized into two groups. The animals were either intubated conventionally using direct laryngoscopy or a single-use flexible video-endoscope. The intervention was carried out by providers with 3 months experience in conventional intubation of pigs and a brief introduction into endoscopy. Intubation attempts were supervised and aborted, when SpO2 dropped below 93%. After three failed attempts, an experienced supervisor intervened and performed the intubation. Intubation times and attempts were recorded and analysed.

Results

Flexible fibreoptic intubation showed a significantly higher success rate in first attempt endotracheal tube placement (75% vs. 47%) with less attempts overall (1.3 ± 0.6 vs. 2.1 ± 1.3, P = 0.043). Conventional intubation was faster (42 s ± 6 s vs. 67 s ± 10s, P < 0.001), but showed a higher complication rate and more desaturation episodes during the trial.

Conclusions

Flexible fibreoptic intubation in swine is feasible and appears to be a safer and more accessible method for inexperienced users to learn. This could not only improve resident training options in hospitals with animal research facilities but might also prevent airway complications and needless animal suffering.

Preemptive veno-venous ECMO support in a patient with anticipated difficult airway: A case report

This report presents a case of endotracheal metastasis in which elective veno-venous extracorporeal membrane oxygenation (VV ECMO) was used to undergo tracheal laser-surgery prior to establishment of a definitive airway. Specifically, we describe the respiratory and airway management in an adult patient from the preclinical phase throughout elective preoperative ECMO implantation to postoperative ECMO weaning and decannulation in the Intensive Care Unit. This case report lends further supports to the idea that the extracorporeal membrane oxygenation could be electively used to provide safe environment for surgery in situations where the standard maneuvers of sustaining adequate gas exchange are anticipated to fail.

Recommendations for the evaluation and management of the anticipated and non-anticipated difficult airway of the Societat Catalana d'Anestesiologia, Reanimació i Terapèutica del Dolor, based on the adaptation of clinical practice guidelines and expert consensus

The Airway Division of the Catalan Society of Anaesthesiology, Intensive Care and Pain Management (SCARTD) presents its latest guidelines for the evaluation and management of the difficult airway. This update includes the technical advances and changes observed in clinical practice since publication of the first edition of the guidelines in 2008. The recommendations were defined by a consensus of experts from the 19 participating hospitals, and were adapted from 5 recently published international guidelines following an in-depth analysis and systematic comparison of their recommendations. The final document was sent to the members of SCARTD for evaluation, and was reviewed by 11 independent experts. The recommendations, therefore, are supported by the latest scientific evidence and endorsed by professionals in the field. This edition develops the definition of the difficult airway, including all airway management techniques, and places emphasis on evaluating and classifying the airway into 3 categories according to the anticipated degree of difficulty and additional safety considerations in order to plan the management strategy. Pre-management planning, in terms of preparing patients and resources and optimising communication and interaction between all professionals involved, plays a pivotal role in all the scenarios addressed. The guidelines reflect the increased presence of video laryngoscopes and second-generation devices in our setting, and promotes their routine use in intubation and their prompt use in cases of unanticipated difficult airway. They also address the increased use of ultrasound imaging as an aid to evaluation and decision-making. New scenarios have also been included, such as the risk of bronchoaspiration and difficult extubation Finally, the document outlines the training and continuing professional development programmes required to guarantee effective and safe implementation of the guidelines.

An international survey of airway management education in 61 countries†

BACKGROUND

Deficiencies in airway management skills and judgement contribute to poor outcomes. Airway management practice guidelines emphasise the importance of education. Little is known about the global uptake of guidelines, availability of equipment, provision of training, assessment of skills, and confidence with procedures.

METHODS

We devised a survey to examine these issues. Initially, 24 127 anaesthetists were questioned in New Zealand, Canada, South Africa, UK, India, and Germany, representing the home countries of the members of the Worldwide Airway Meeting (2015) Education Group; however, the survey could be forwarded to others. The survey was open for a maximum of 90 days.

RESULTS

We received 4948 fully or partially completed surveys from 61 countries: 33 high-income and 28 middle- or low-income countries. Most respondents were consultants (77.2%, n=4948), and the remainder trainees, with a male/female ratio of 1.8:1 (3105 males, n=4866). Of those responding, 1358 (76.6%, n=1798) were members of an airway interest group. Most respondents (91.3% of 2910) agreed with assessment of airway skills, fewer (2237; 59.7%, n=3750) reported requiring airway training for completion of training, and only 810 (33.6%, n=2408) reported it as a requirement for continuing medical education. Reported confidence was lowest for awake tracheal intubation, front-of-neck access, and retrograde intubation.

CONCLUSIONS

Global training is variable in its delivery and necessity. Confidence is limited in potentially life-saving techniques. The desire for assessment appears universal and may improve standards, but in resource- or time-limited environments this will be challenging.

Critical language during an airway emergency: Time to rethink terminology?

Clear language should be used during emergency airway management to aid communication and understand the nature of the emergency. Unfortunately, during emergency airway management, there is no uniform language used for communication. Various difficult airway guidelines use different terminologies. Terminologies like “can't intubate, can't oxygenate” (CICO) and “can't intubate, can't ventilate” (CICV) have certain limitations. Though terminology like “Front of Neck Access” (FONA) is dominant in the literature,”emergency cricothyroidotomy” is used more often in clinical practice, suggesting a disconnect between the dominant terminology in the literature and in clinical practice. Terminology should not be used merely because it is catchy, simple and advocated by a few. It must accurately reflect the nature of the situation, convey a sense of urgency, and suggest an action sequence. An initiative to achieve consensus among existing terminologies is much needed. Leaders in the field should work towards refining airway terminology and replace poor phrases with ones that are more concise, precise and can be used universally in an airway emergency.

Methodological quality and transparency of clinical practice guidelines for difficult airway management using the appraisal of guidelines research & evaluation II instrument: A systematic review

BACKGROUND

Complications arising from airway management represent an important cause of morbidity and mortality. Clinical practice guidelines (CPGs) are systematically created documents that summarise knowledge and assist the delivery of high-quality medical care by identifying evidence that supports best clinical care.

OBJECTIVE

Using the Appraisal of Guidelines for Research & Evaluation II instrument, we aimed to evaluate the methodological rigour and transparency of unanticipated difficult airway management CPGs in adults.

DESIGN

Using PUBMED without language restrictions, we identified eligible CPGs between 1 January 1996 and 30 June 2019. All versions of a CPG were included as independent guidelines to assess improvements over time or the methodological limitations of each version. CPGs-related obstetrics or paediatrics or the management extubation in cases of difficult airway were excluded.

RESULTS

Fourteen CPGs were included. Of the six domains suggested by the Appraisal of Guidelines for Research & Evaluation II instrument, 'applicability' had the lowest score (23%) and 'scope and objectives' had the highest score (88%). The remaining domains (stakeholder involvement, editorial independence, rigour of development and clarity of presentation) had scores ranging between 56 and 81%. Overall, the highest scored CPG was the Difficult Airway Society 2015.

CONCLUSION

Future updates of CPGs for difficult airway management in adults and severely ill patients should consider more emphasis on the applicability of their recommendations to real clinical practice.

Depth of anesthesia by Narcotrend® and postoperative characteristics in children undergoing cardiac surgery under extracorporeal circulation: a retrospective comparison of two anesthetic regimens

BACKGROUND

Depth of anesthesia may be insufficient in pediatric cardiac anesthesia if a total intravenous anesthetic regimen with opioids and midazolam is used during cardiopulmonary bypass. The advantages of sevoflurane-based balanced anesthesia may be (1) a more graduated regulation of the depth of anesthesia during cardiopulmonary bypass and (2) a reduction in postoperative ventilation time for children in comparison with total intravenous anesthesia.

AIM

To evaluate a possibly positive effect of sevoflurane-based balanced anesthesia in children undergoing cardiac surgery we analyzed whether this anesthetic regimen had a significant effect related to (1) depth of anesthesia, (2) the need for opioids during cardiopulmonary bypass as well as on postoperative characteristics such as (3) time of postoperative ventilation, and (4) duration of stay in the intensive care unit in comparison with total intravenous anesthesia.

METHODS

In a retrospective analysis, data from heart-lung machine protocols from 2013 to 2016 were compared according to anesthetic regimen (sevoflurane-balanced anesthesia, n = 70 vs. total intravenous anesthesia, n = 65). Children (age: 8 weeks to 14 years) undergoing cardiac surgery with cardiopulmonary bypass were included. As a primary outcome measure, we compared Narcotrend^® system-extracted data to detect insufficient phases of anesthetic depth during extracorporeal circulation under moderate hypothermia. Postoperatively, we measured the postoperative ventilation time and the number of days in the intensive care unit. Furthermore, we analyzed patients' specific characteristics such as opioid consumption during cardiopulmonary bypass. Regression analysis relating primary objectives was done using the following variables: anesthetic regimen, age, severity of illness/surgery, and cumulative dosage of opiates during cardiopulmonary bypass.

RESULTS

No significant differences were observed in descriptive patient characteristics (age, body weight, height, and body temperature) between the two groups. Further, no significant differences were found in depth of anesthesia by analyzing phases of superficial B1-C2-electroencephalography Narcotrend^® data. No marked difference between the groups was observed for the duration of postoperative intensive care unit stay. However, the postoperative ventilation time (median (95% CI, hours)) was significantly lower in the sevoflurane-based balanced anesthesia group (6.0 (2.0-15.0)) than in the total intravenous anesthesia group (13.5 (7.0-25)). A higher dosage of opioids and midazolam was required in the total intravenous anesthesia group to maintain adequate anesthesia during cardiopulmonary bypass. Regression analysis showed an additional, significant impact of the following factors: severity of illness and severity grade of cardiac surgery (according to Aristotle) on the primary endpoint.

CONCLUSION

In children undergoing cardiac surgery in our department, the use of sevoflurane-balanced anesthesia during cardiopulmonary bypass showed no superiority of inhalational agents over total intravenous anesthesia with opioids and benzodiazepines preventing phases of superficial anesthesia, but a marked advantage for the postoperative ventilation time compared with total intravenous anesthesia.

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

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

Availability and organization of difficult airway equipment in Swedish hospitals: A national survey of anaesthesiologists

BACKGROUND

Airway complications account for almost one third of anaesthesia-related brain damage and death. Immediate access to equipment enabling rescue airway strategies is crucial for successful management of unanticipated difficult airway situations.

METHODS

We conducted a nationwide survey of Swedish anaesthesiologists to analyse availability and organization of difficult airway trolleys (DATs), and multiple factors pertaining to difficult airway management, to highlight areas of potential improvement.

RESULTS

Six hundred and thirty-nine anaesthesiologists completed the 14-item survey. Whereas DATs were almost ubiquitous (95%) in main operating departments of hospitals, prevalence was low in remote anaesthetizing locations (20.3%) and electroconvulsive therapy units (26.6%). Approximately 60% of emergency departments had a DAT. Immediate (within 60 seconds) access to videolaryngoscopes in all units where general anaesthesia is conducted was reported by 56.8%. Almost half of anaesthesiologists reported that all DATs at their workplace were standardized. Forty-six per cent reported that the DATs were organized according to a difficult airway algorithm; almost 90% believe that such an organization can impact the outcome of a difficult airway situation positively. Only 36.2% of DATs contained second-generation supraglottic airway devices exclusively. Most Swedish anaesthesiologists use the Swedish Society of Anaesthesiology and Intensive care Medicine difficult airway algorithm, but almost one fifth prefer the Difficult Airway Society algorithm. Less than half of respondents underwent formal difficult airway training annually.

CONCLUSION

Our results motivate efforts to (a) increase availability of DATs in remote anaesthetizing locations, (b) increasingly standardize DATs and organize DATs according to airway algorithms, and (c) increase the frequency of difficult airway training.

[Physiological changes during pregnancy]

The physiological state of a woman experiences multiple changes in the body during pregnancy. These alterations could be of particular importance in the medical care of pregnant women. This review article highlights the physiological developments of various organ systems throughout gestation with a focus on endocrinology, the cardiovascular system, hematology, the respiratory system and water balance.

Supraglottic devices for airway management in awake craniotomy

Awake craniotomy is a unique technique utilized for mapping neuro and motor function during neurosurgical procedures close to eloquent brain tissue. Since active communication is required only during surgical manipulation of eloquent brain tissue and the patient is "sedated" during other parts of the procedure, different methods for anesthesia management have been explored. Furthermore, airway management ranges from spontaneous breathing to oro or nasotracheal intubation. Case reports have described the use of laryngeal masks (LMs) previously; however, its safety compared to tracheal intubation has not been assessed.We conducted a retrospective analysis of 30 patients that underwent awake craniotomy for tumor surgery to compare the feasibility and safety of different airway management strategies. Nasal fiberoptic intubation (FOI) was performed in 21 patients while 9 patients received LM for airway management. Ventilation, critical events, and perioperative complications were evaluated.Cannot intubate situation occurred in 4 cases reinserting the tube after awake phase, while no difficulties were described reinserting the LM (P < .0001). Furthermore, duration of mechanical ventilation after tumor removal was significantly lower in the LM group compared to FOI group (62 ± 24 vs. 339 ± 82 [min] mean ± sem, P < .0001). Postoperatively, 2 patients in each group were diagnosed with and treated for respiratory complications including pneumonia, without statistical significance between groups.In summary, LM is a feasible airway management method for patients undergoing awake craniotomy, resulting in reduced ventilation duration compared to FOI procedure.