Strategies and algorithms for management of the difficult airway

Derivation of the Difficult Airway Physiological Score (DAPS) in adults undergoing endotracheal intubation in the emergency department

BACKGROUND

Prediction of serious outcomes among patients with physiological instability is crucial in airway management. In this study, we aim to develop a score to predict serious outcomes following intubation in critically ill adults with physiological instability by using clinical and laboratory parameters collected prior to intubation.

METHOD

This single-center analytical cross-sectional study was conducted in the Emergency Department from 2016 to 2020. The airway score was derived using the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) methodology. To gauge model's performance, the train-test split technique was utilized. The discrete random number generation approach was used to divide the dataset into two groups: development (training) and validation (testing). The validation dataset's instances were used to calculate the final score, and its validity was measured using ROC analysis and area under the curve (AUC). By computing the Youden's J statistic using the metrics sensitivity, specificity, positive predictive value, and negative predictive value, the discriminating factor of the additive score was determined.

RESULTS

The mean age of the 1021 patients who needed endotracheal intubations was 52.2 years (± 17.5), and 632 (62%) of them were male. In the development dataset, there were 527 (64.9%) physiologically difficult airways, 298 (36.7%) post-intubation hypotension, 124 (12%) cardiac arrest, 347 (42.7%) shock index > 0.9, and 456 [56.2%] instances of pH < 7.3. On the contrary, in the validation dataset, there were 143 (68.4%) physiologically difficult airways, 33 (15.8%) post-intubation hypotension, 41 (19.6%) cardiac arrest, 87 (41.6%) shock index > 0.9, and 121 (57.9%) had pH < 7.3, respectively. There were 12 variables in the difficult airway physiological score (DAPS), and a DAPS of 9 had an area under the curve of 0.857. The accuracy of DAPS was 77%, the sensitivity was 74%, the specificity was 83.3%, and the positive predictive value was 91%.

CONCLUSION

DAPS demonstrated strong discriminating ability for anticipating physiologically challenging airways. The proposed model may be helpful in the clinical setting for screening patients who are at high risk of deterioration.

Effectiveness, quality and implementation of pain, sedation, delirium, and iatrogenic withdrawal syndrome algorithms in pediatric intensive care: a systematic review and meta-analysis

Background

Pain, sedation, delirium, and iatrogenic withdrawal syndrome are conditions that often coexist, algorithms can be used to assist healthcare professionals in decision making. However, a comprehensive review is lacking. This systematic review aimed to assess the effectiveness, quality, and implementation of algorithms for the management of pain, sedation, delirium, and iatrogenic withdrawal syndrome in all pediatric intensive care settings.

Methods

A literature search was conducted on November 29, 2022, in PubMed, Embase, CINAHL and Cochrane Library, ProQuest Dissertations & Theses, and Google Scholar to identify algorithms implemented in pediatric intensive care and published since 2005. Three reviewers independently screened the records for inclusion, verified and extracted data. Included studies were assessed for risk of bias using the JBI checklists, and algorithm quality was assessed using the PROFILE tool (higher % = higher quality). Meta-analyses were performed to compare algorithms to usual care on various outcomes (length of stay, duration and cumulative dose of analgesics and sedatives, length of mechanical ventilation, and incidence of withdrawal).

Results

From 6,779 records, 32 studies, including 28 algorithms, were included. The majority of algorithms (68%) focused on sedation in combination with other conditions. Risk of bias was low in 28 studies. The average overall quality score of the algorithm was 54%, with 11 (39%) scoring as high quality. Four algorithms used clinical practice guidelines during development. The use of algorithms was found to be effective in reducing length of stay (intensive care and hospital), length of mechanical ventilation, duration of analgesic and sedative medications, cumulative dose of analgesics and sedatives, and incidence of withdrawal. Implementation strategies included education and distribution of materials (95%). Supportive determinants of algorithm implementation included leadership support and buy-in, staff training, and integration into electronic health records. The fidelity to algorithm varied from 8.2% to 100%.

Conclusions

The review suggests that algorithm-based management of pain, sedation and withdrawal is more effective than usual care in pediatric intensive care settings. There is a need for more rigorous use of evidence in the development of algorithms and the provision of details on the implementation process.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021276053, PROSPERO [CRD42021276053].

Challenges in Anaesthetic Management in a Case of Facial Plexiform Neurofibromatosis Posted for Debulking Surgery

A patient diagnosed with facial plexiform neurofibromatosis type 1 who is 18 years old and is scheduled for tumour resection and debulking surgery of his face is the subject of this study. The purpose of this paper is to describe the anaesthetic treatment that was administered to this patient. In addition, we analyze the relevant literature, with a particular emphasis on the implications of modifying neurofibromatosis to achieve anaesthesia. Our patient was found to have multiple huge tumours all over his face. When he first arrived, he experienced cervical instability as a result of the enormous mass on the back of his head and in the region of his scalp. He also expected to have difficulty maintaining an airway and breathing through a bag and mask. To protect the patient's airway, a video laryngoscopy was performed, and a difficult airway cart was maintained on standby in the event it was required. In conclusion, the purpose of this case study was to demonstrate the relevance of comprehending the one-of-a-kind anaesthetic requirements of persons diagnosed with neurofibromatosis type 1 who are about to undergo surgical procedures. Neurofibromatosis is an extremely uncommon kind of disease that requires the anesthesiologist's undivided attention in surgical settings. Careful pre-operative planning and competent intra-operative treatment are required when dealing with patients who are expected to have difficult airway management.

Multidisciplinary Difficult Airway Team Characteristics, Airway Securement Success, and Clinical Outcomes: A Systematic Review

Objective:

To investigate whether implementation of a multidisciplinary airway team was associated with improvement in (1) rate of successful airway securement at first attempt; (2) time to secure airway; and (3) overall complication rate in patients with a difficult airway, as compared with usual care.

Data Sources:

Ovid Medline, Embase, Scopus, Cochrane Central, and CINAHL databases.

Review Methods:

Systematic review of literature on inpatient multidisciplinary team management of difficult airways, including all studies performed in inpatient settings, excluding studies of ventilator weaning, flight/military medicine, EXIT procedures, and simulation or educational studies. DistillerSR was used for article screening and risk of a bias assessment to evaluate article quality. Data was extracted on study design, airway team composition, patient characteristics, and clinical outcomes including airway securement, complications, and mortality.

Results:

From 5323 studies screened, 19 studies met inclusion criteria with 4675 patients. Study designs included 12 quality improvement projects, 6 cohort studies, and 1 randomized controlled trial. Four studies evaluated effect of multidisciplinary difficult airway teams on airway securement; all reported higher first attempt success rate with team approach. Three studies reported time to secure the difficult airways, all reporting swifter airway securement with team approach. The most common difficult airway complications were hypoxia, esophageal intubation, hemodynamic instability, and aspiration. Team composition varied, including otolaryngologists, anesthesiologists, intensivists, nurses, and respiratory care practitioners.

Conclusion:

Multidisciplinary difficult airway teams are associated with improved clinical outcomes compared to unstructured emergency airway management; however, studies have significant heterogeneity in team composition, algorithms for airway securement, and outcomes reported. Further evidence is necessary to define the clinical efficacy, cost-effectiveness, and best practices relating to implementing difficult airway teams in inpatient settings.

Using Lean tools to improve the efficiency of awake fibreoptic intubation setup

Background

Awake fibreoptic intubation is a complex advanced airway technique used by anaesthesiologists in the management of a difficult airway. The time to setup this important procedure can be significant which may dissuade its use by some providers. In our institution, the awake intubation setup process was highly variable and error prone.

Methods

We deployed Lean methods to improve the efficiency and accuracy of the awake fibreoptic intubation setup process. A 2-day improvement event with a multidisciplinary team addressed the setup process, tested solutions and created standard work documents. Twenty awake fibreoptic intubation simulations were conducted before and after the intervention to quantify gains in setup efficiency and error reduction.

Results

Variability in the setup process, including clinical locations visited, was reduced through creating a standardised process. The average time to for an awake fibreoptic intubation setup was reduced by approximately 50%, from 23 min to 11 min (p<0.001). In addition, awake fibreoptic intubation equipment set out without error increased in the postintervention simulations from 59% to 85% (p=0.003).

Conclusion

Using Lean tools, we were able to make the setup of awake fibreoptic intubation not only more efficient, but also more accurate. A similar methodological approach may have value for other complex anaesthesia procedures.

[Manikin-based comparison of the use of different supraglottic airways by laypersons]

BACKGROUND

Supraglottic airways (SGA) are an established method of airway management both in prehospital medicine and clinical settings. Endotracheal intubation is the gold standard, but SGA offer advantages in terms of faster application learnability.

OBJECTIVES

In the present study it was investigated whether the time until the first sufficient ventilation in the three examined SGAs applied by bystander differed significantly.

MATERIALS AND METHODS

A total of 160 visitors to a shopping mall were assigned to one of the three SGA after permutative block randomization. The primary endpoint of the present study was the required placement time until the first sufficient ventilation.

RESULTS

Participants managed to place the i‑gel laryngeal mask airway (i-gel, Intersurgical Beatmungsprodukte GmbH, Sankt Augustin, Germany) after a median time of 11 s, whereas the median time until the first sufficient ventilation using a classic laryngeal mask airway (LMA; 26 s) or a laryngeal tube (LT; 28 s) was significantly longer. Thus, the time savings when using the i‑gel compared to the LT and LMA were each significant (p < 0.001), whereas the times between LT and LMA did not differ significantly (p 0.65).

CONCLUSION

The results show that laypersons are able to successfully apply various supraglottic airways to the phantom after a short learning period. The i‑gel laryngeal mask could be placed with the highest success rate and speed.

Comparison of Conventional Technique versus Modified Tube First Technique of Awake Nasotracheal Fiber-optic Intubation: A Randomized Control Open-Label Trial

Background:

Although the conventional awake fiber-optic nasal intubation is most commonly used in anticipated difficult tracheal intubation, it has several potential difficulties.

Aims:

The aim of this study is to compare another technique modified tube first (MTF) technique with the conventional one in terms of time taken, ease of glottis visualization, number of attempts needed, and complications.

Settings and Design:

This was a prospective, randomized, open-label trial conducted on 60 patients with an anticipated difficult airway undergoing oromaxillofacial surgery at a tertiary care center.

Materials and Methods:

The patients were randomized into the MTF and conventional technique groups. Times from insertion of the fiber-optic scope into nares till vocal cord visualization (T1) and from T1 to complete intubation (T2) were measured and compared.

Statistical Analysis Used:

Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) software version 21.

Results:

Time taken to visualize glottis was significantly less in the MTF technique as compared to the conventional method (mean ± standard deviation = 108.6 ± 43.1 vs. 142 ± 49.2 s, respectively, P = 0.007). Similarly, the total time taken for nasotracheal intubation with modified technique is significantly less as compared to the conventional technique (P = 0.004). Furthermore, there is significantly better ease of glottis visualization (P = 0.001), higher success in minimal attempts (P = 0.02) with significantly lesser incidence of desaturation in MTF technique (P = 0.026).

Conclusion:

The alternative technique (MTF) is a quicker, easier approach with higher success rate and lesser complications for the placement of an endotracheal tube in a difficult airway scenario.

Management of the Unexpected Difficult Airway in Neonatal Resuscitation

A "difficult airway situation" arises whenever face mask ventilation, laryngoscopy, endotracheal intubation, or use of supraglottic device fail to secure ventilation. As bradycardia and cardiac arrest in the neonate are usually of respiratory origin, neonatal airway management remains a critical factor. Despite this, a well-defined in-house approach to the neonatal difficult airway is often lacking. While a recent guideline from the British Pediatric Society exists, and the Scottish NHS and Advanced Resuscitation of the Newborn Infant (ARNI) airway management algorithm was recently revised, there is no Norwegian national guideline for managing the unanticipated difficult airway in the delivery room (DR) and neonatal intensive care unit (NICU). Experience from anesthesiology is that a "difficult airway algorithm," advance planning and routine practicing, prepares the resuscitation team to respond adequately to the technical and non-technical stress of a difficult airway situation. We learned from observing current approaches to advanced airway management in DR resuscitations in a university hospital and make recommendations on how the neonatal difficult airway may be managed through technical and non-technical approaches. Our recommendations mainly pertain to DR resuscitations but may be transferred to the NICU environment.

Difficult airway management algorithms: a directed review

The primary aim of this study was to identify, describe and compare the content of existing difficult airway management algorithms. Secondly, we aimed to describe the literature reporting the implementation of these algorithms. A directed search across three databases (MEDLINE, Embase and Scopus) was performed. All articles were screened for relevance to the research aims and according to pre-determined exclusion criteria. We identified 38 published airway management algorithms. Our results show that most facemask employ a four-step process as represented by a flow chart, with progression from tracheal intubation, facemask ventilation and supraglottic airway device use, to a rescue emergency surgical airway. The identified algorithms are overwhelmingly similar, yet many use differing terminology. The frequency of algorithm publication has increased recently, yet adherence and implementation outcome data remain limited. Our results highlight the lack of a single algorithm that is universally endorsed, recognised and applicable to all difficult airway management situations.

Preparation for and Management of “Failed” Laryngoscopy and/or Intubation

An airway manager’s primary objective is to provide a path to oxygenation. This can be achieved by means of a facemask, a supraglottic airway, or a tracheal tube. If one method fails, an alternative approach may avert hypoxia. We cannot always predict the difficulties with each of the methods, but these difficulties may be overcome by an alternative technique. Each unsuccessful attempt to maintain oxygenation is time lost and may incrementally increase the risk of hypoxia, trauma, and airway obstruction necessitating a surgical airway. We should strive to optimize each effort. Differentiation between failed laryngoscopy and failed intubation is important because the solutions differ. Failed facemask ventilation may be easily managed with an supraglottic airway or alternatively tracheal intubation. When alveolar ventilation cannot be achieved by facemask, supraglottic airway, or tracheal intubation, every anesthesiologist should be prepared to perform an emergency surgical airway to avert disaster.

Decision-centred design in healthcare: The process of identifying a decision support tool for airway management

Current decision support interventions for airway management in anaesthesia lack the application of Human Factors Engineering; leading to interventions that can be disruptive, inefficient and error-inducing. This study followed a decision-centred design process to identify decision support that can assist anaesthesia teams with challenging airway management situations. Field observations, Critical Decision Method interviews and focus groups were conducted to identify the most difficult decisions and their requirements. Data triangulation narrowed the focus to key decisions related to preparation and planning, and the transitioning between airway techniques during difficulties. Five decision-support interventions were identified and positively rated by anaesthesia team members in relation to their perceived effectiveness. An organized airway equipment trolley was chosen as the most beneficial decision support intervention. This study reiterated the key importance of both Human Factors Engineering and data triangulation when designing for healthcare.

A prospective cohort study of awake fibreoptic intubation practice at a tertiary centre

Contemporary data are lacking for procedural practice, training provision and outcomes for awake fibreoptic intubation in the UK. We performed a prospective cohort study of awake fibreoptic intubations at a tertiary centre to assess current practice. Data from 600 elective or emergency awake fibreoptic intubations were collected to include information on patient and operator demographics, technical performance and complications. This comprised 1.71% of patients presenting for surgery requiring a general anaesthetic, with the majority occurring in patients presenting for head and neck surgery. The most common indication was reduced mouth opening (26.8%), followed by previous airway surgery or head and neck radiotherapy (22.5% each). Only five awake fibreoptic intubations were performed with no sedation, but the most common sedative technique was combined target-controlled infusions of remifentanil and propofol. Oxygenation was achieved with high-flow, heated and humidified oxygen via nasal cannula in 49.0% of patients. Most operators had performed awake fibreoptic intubation more than 20 times previously, but trainees were the primary operator in 78.6% of awake fibreoptic intubations, of which 86.8% were directly supervised by a consultant. The failure rate was 1.0%, and 11.0% of awake fibreoptic intubations were complicated, most commonly by multiple attempts (4.2%), over-sedation (2.2%) or desaturation (1.5%). The only significant association with complications was the number of previous awake fibreoptic intubations performed, with fewer complications occurring in the hands of operators with more awake fibreoptic intubation experience. Our data demonstrate that awake fibreoptic intubation is a safe procedure with a high success rate. Institutional awake fibreoptic intubation training can both develop and maintain trainee competence in performing awake fibreoptic intubation, with a similar incidence of complications and success compared with consultants.

[Management of the difficult airway : Overview of the current guidelines]

Several national airway task forces have recently updated their recommendations for the management of the difficult airway in adults. Routinely responding to airway difficulties with an algorithm-based strategy is consistently supported. The focus is increasingly not on tools and devices but more on good planning, preparation and communication. In the case of anticipated airway difficulties the airway should be secured when the patient is awake with maintenance of spontaneous ventilation. Unaltered a flexible bronchoscopic intubation technique is advised as a standard of care in such patients. The importance of maintenance of oxygenation is emphasized. Face mask ventilation and the use of supraglottic devices are recommended if unexpected airway difficulties occur. Face mask ventilation may be facilitated and optimised by early administration of neuromuscular blocking agents. If required, in not fastened patients threatened by acute hypoxia, carefully applied and pressure-controlled ventilation may ensure sufficient oxygenation until the airway is secured. Apnoeic oxygen techniques are recommended in high-risk patients and to relieve the time pressure of falling oxygen saturation during decision-making processes. The early use of video laryngoscopy is advised for endotracheal intubation in the case of failed direct laryngoscopy or if intubation is expected to be difficult. For the coverage of cannot intubate-cannot oxygenate scenarios, second generation supraglottic devices and invasive airway access are advocated. The discussion regarding the optimal technique for emergency invasive airway access is still in progress. In the case of uncontrollable respiratory deterioration and progressive hypoxia, the algorithm must be consistently executed and without delay due to ineffective activities (straightforward strategy). Although there is no evidence to support the selection of a particular approach, the importance and the need for a defined airway concept/algorithm in any anesthesia department is fostered. Simplicity and clarity are essential for recall under stressful and time-sensitive conditions. The algorithm should be adapted to local conditions and preferences and devices should be limited to a definite number. The acquisition and maintenance of expertise by education and training is demanded.

National survey on airway and difficult airway management in intensive care units

OBJECTIVE

To know organization, management and training in airway (AW) in Spanish Intensive Care Units (ICUs), with special interest in difficult airway (DAW).

DESIGN

Descriptive cross-sectional study and χ² subanalysis, conducted through a national survey from november 1th to december 15th, 2016. With the SEMICYUC's support, an online questionnaire of 27 items was sent to 179 ICUs.

SETTING

ICUs of public, private centers, and consortia.

RESULTS

In total, 101 units responded (56.4%), corresponding to 1,827 beds and almost 95,000 incomes/year. The 85.1% are public hospitals, and 83.2% had residents. Of the responders, 22.8% don't use routinely AW assessment scales, being the most frequently used the Cormack-Mallampati association (35.6%). There's not intubation (IOT) protocol in 77.2%, nor DAW protocol in 75.2%. An 82.2% have a DAW cart. The 48.5% have training in IOT, and in VAD 53.5%. Having a DAW expert is significantly associated with greater training in IOT (60% vs. 39.3%; P=.03), DAW (64.4% vs. 44.6%; P=.04), and more AW protocols (73.4% vs. 37.5%; P=.000). Having an specific guideline for DAW management in UCI is considered necessary in 99%.

CONCLUSIONS

There is room for improvement in AW management. It's necessary to identify an expert in DAW in each Unit, and the development of an specific guideline for DAW management in critical care.

Survey about the Extubation Practice among Anaesthesiologists in Kosovo

BACKGROUND

Tracheal extubations may be performed before or after awakening from anaesthesia. The advantage of extubation during anaesthesia may avoid all the unpleasant effects of fully awake extubation such as severe hypertension and tachycardia, malignant dysrhythmias, myocardial ischemia laryngospasm, and cough induced high intraocular and intracranial pressure.

AIM

To show the current practice of performing extubations in Kosovo, as well as the advantage and disadvantage in performing this procedure in an awake patient or inpatient in light anaesthesia.

MATERIAL

This study is conducted at the Regional Hospitals and the University Clinical Center of Kosovo during the year 2015. A questionnaire is given to the anesthesiologists to collect information about the techniques used for extubation, timing and management of extubation.

RESULTS

Based on this survey results that 86% of an anesthesiologist (71) extubate the patients when they are completely awake, while 14% of them (12) prefer to extubate the patients under light anaesthesia. From all anesthesiologists involved in this study, forty of them reported problems during extubation. Complications were related to airway, and they are treated by oxygenation and jaw support, but in rare cases, reintubation were performed.

CONCLUSION

Complications during extubation remain important risk factor while extubation during light anaesthesia can minimise some of them.

The Neurocritical and Neurosurgical Care of Subdural Hematomas

Subdural hematomas (SDHs), though frequently grouped together, can result from a variety of different etiologies, and therefore many different subtypes exist. Moreover, the high incidence of these lesions in the neurocritical care settings behooves practitioners to have a firm grasp on their diagnosis and management. We present here a review of SDHs, with an emphasis on how different subtypes of SDHs differ from one another and with discussion of their medical and surgical management in the neurocritical care setting. In this paper, we discuss considerations for acute, subacute, and chronic SDHs and how presentation and management may change in both the elderly and pediatric populations. We discuss SDHs that arise in the setting of anticoagulation, those that arise in the setting of active cerebrospinal fluid diversion, and those that are recurrent and recalcitrant to initial surgical evacuation. Management steps reviewed include detailed discussion of initial assessment, anticoagulation reversal, seizure prophylaxis, blood pressure management, and indications for intracranial pressure monitoring. Direct surgical management options are reviewed, including open craniotomy, twist-drill, and burr-hole drainage and the usage of subdural drainage systems. SDHs are a common finding in the neurocritical care setting and have a diverse set of presentations. With a better understanding of the fundamental differences between subtypes of SDHs, critical care practitioners can better tailor their management of both the patient's intracranial and multi-systemic pathologies.

Insertion Success of the Laryngeal Tube in Emergency Airway Management

Background. Emergency airway management (AM) is a priority when resuscitating critically ill or severely injured patients. The goal of this study was to determine the success rates of LT insertion during AM. Methods. Studies that included LT first-pass insertion (FPI) and overall-pass insertion (OPI) success by emergency medical services and in-hospital providers performing AM for emergency situations as well as for scheduled surgery published until July 2014 were searched systematically in Medline. Results. Data of 36 studies (n = 1,897) reported a LT FPI success by physicians of 82.5% with an OPI success of 93.6% (p < 0.001). A cumulative analysis of all 53 studies (n = 3,600) led to FPI and OPI success of 80.1% and 92.6% (p < 0.001), respectively. The results of 26 studies (n = 2,159) comparing the LT with the laryngeal mask airway (LMA) demonstrated a FPI success of 77.0 versus 78.7% (p = 0.36) and an OPI success of 92.2 versus 97.7% (p < 0.001). Conclusion. LT insertion failed in the first attempt in one out of five patients, with an overall failure rate in one out of 14 patients. When compared with the LT, the LMA had a cumulative 5.5% better OPI success rate.

Distance from the glottis to the grille: the LMA Unique, Air-Q and CobraPLA as intubation conduits: a randomised trial

BACKGROUND

Supraglottic airway devices are often used in airway management to facilitate tracheal intubation. Knowledge of the distance from the grille of the device to the patient's vocal cords is essential for the safe passage of the tracheal tube below the vocal cords.

OBJECTIVES

To assess the distance from the glottis to the grille of three supraglottic airway devices [LMA (LMA Unique), Air-Q (Air-Q Intubating Laryngeal Airway Reusable) and CobraPLA (Cobra Perilaryngeal Airway)] and their safe usage as intubation conduits.

DESIGN

Randomised controlled trial.

SETTING

Tertiary, university hospital.

PATIENTS

Thirty women undergoing elective gynaecological surgery with planned supraglottic airway management.

INTERVENTIONS

In-vivo fibreoptic assessment and in-vitro measurement.

MAIN OUTCOME MEASURES

The distance from the grille to the glottis was defined as primary outcome. The distance from the beginning of the cuff of a tracheal tube passed through the device to the grille was assessed as secondary outcome.

RESULTS

The three devices exhibited significant differences in the mean ± SD distance from the glottis to the grille (LMA 4.6 ± 1.5  cm, Air-Q 5.7 ± 1.4  cm, CobraPLA 3.4 ± 1.4  cm; P = 0.009). The Air-Q was predicted to allow the safe passage of a tracheal tube into the trachea, whereas the cuff was predicted to rest on the vocal cords in 57% of the LMA patients and 14% of the CobraPLA patients.

CONCLUSION

Using the LMA Unique as a conduit for tracheal intubation may pose a safety risk, whereas the use of the Air-Q would position the tracheal tube at a safe depth in the trachea.

A nationwide postal questionnaire survey: the presence of airway guidelines in anaesthesia department in Sweden

Background

In Sweden, airway guidelines aimed toward improving patient safety have been recommended by the Swedish Society of Anaesthesia and Intensive Care Medicine. Adherence to evidence-based airway guidelines is known to be generally poor in Sweden. The aim of this study was to determine whether airway guidelines are present in Swedish anaesthesia departments.

Methods

A nationwide postal questionnaire inquiring about the presence of airway guidelines was sent out to directors of Swedish anaesthesia departments (n = 74). The structured questionnaire was based on a review of the Swedish Society of Anaesthesia and Intensive Care voluntary recommendations of guidelines for airway management. Mean, standard deviation, minimum/maximum, percentage (%) and number of general anaesthesia performed per year as frequency (n), were used to describe, each hospital type (university, county, private). For comparison between hospitals type and available written airway guidelines were cross tabulation used and analysed using Pearson’s Chi-Square tests. A p- value of less than 0 .05 was judged significant.

Results

In total 68 directors who were responsible for the anaesthesia departments returned the questionnaire, which give a response rate of 92% (n 68 of 74). The presence of guidelines showing an airway algorithm was reported by 68% of the departments; 52% reported having a written patient information card in case of a difficult airway and guidelines for difficult airways, respectively; 43% reported the presence of guidelines for preoperative assessment; 31% had guidelines for Rapid Sequence Intubation; 26% reported criteria for performing an awake intubation; and 21% reported guidelines for awake fibre-optic intubation. A prescription for the registered nurse anaesthetist for performing tracheal intubation was reported by 24%. The most frequently pre-printed preoperative elements in the anaesthesia record form were dental status and head and neck mobility.

Conclusions

Despite recommendations from the national anaesthesia society, the presence of airway guidelines in Swedish anaesthesia departments is low. From the perspective of safety for both patients and the anaesthesia staff, airway management guidelines should be considered a higher priority.

Observations on the assessment and optimal use of videolaryngoscopes

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

[Emergency anesthesia, airway management and ventilation in major trauma. Background and key messages of the interdisciplinary S3 guidelines for major trauma patients]

Patients with multiple trauma presenting with apnea or a gasping breathing pattern (respiratory rate  < 6/min) require prehospital endotracheal intubation (ETI) and ventilation. Additional indications are hypoxia (S(p)O(2)  < 90% despite oxygen insufflation and after exclusion of tension pneumothorax), severe traumatic brain injury [Glasgow Coma Scale (GCS)  < 9], trauma-associated hemodynamic instability [systolic blood pressure (SBP)  < 90 mmHg] and severe chest trauma with respiratory insufficiency (respiratory rate  > 29/min). The induction of anesthesia after preoxygenation is conducted as rapid sequence induction (analgesic, hypnotic drug, neuromuscular blocking agent). With the availability of ketamine as a viable alternative, the use of etomidate is not encouraged due to its side effects on adrenal function. An electrocardiogram (ECG), blood pressure measurement and pulse oximetry are needed to monitor the emergency anesthesia and the secured airway. Capnography is absolutely mandatory to confirm correct placement of the endotracheal tube and to monitor tube dislocations as well as ventilation in the prehospital and hospital setting. Because airway management is often complicated in trauma patients, alternative devices need to be available preclinical and a fiber-optic endoscope should be available within the hospital. Use of these alternative measures for airway management and ventilation should be considered at the latest after a maximum of three unsuccessful endotracheal intubation attempts. Emergency medical service (EMS) physicians should to be trained in emergency anesthesia, ETI and alternative methods of airway management on a regular basis. Within hospitals ETI, emergency anesthesia and ventilation are to be conducted by trained and experienced anesthesiologists. When a difficult airway or induction of anesthesia is expected, endotracheal intubation should be supervised or conducted by an anesthesiologist. Normoventilation should be the goal of mechanical ventilation. After arrival in the resuscitation room the ventilation will be controlled and guided with the help of arterial blood gas analyses. After temporary removal of a cervical collar, the cervical spine needs to be immobilized by means of manual in-line stabilization when securing the airway.

Standard clinical risk factors for difficult laryngoscopy are not independent predictors of intubation success with the GlideScope

STUDY OBJECTIVES

To determine whether the first-attempt tracheal intubation incidence using the GlideScope videolaryngoscope is higher in patients with predicted increased risk of difficult laryngoscopy, and to assess the ability of other a priori defined standard risk factors to predict first-attempt intubation success, in aggregate and by forming scores.

DESIGN

Prospective study.

SETTING

Operating room in a tertiary-care academic center.

PATIENTS

357 patients intubated with the GlideScope for nonemergent general anesthesia.

INTERVENTIONS AND MEASUREMENTS

Mallampati airway class was used to create two groups of patients, one with higher and the other, lower, potential difficult laryngoscopy (Mallampati classes 3-4 and 1-2, respectively). Intubation success on the first attempt with the GlideScope videolaryngoscope in patients with a Mallampati class 3 or 4 airway versus those with Mallampati class 1 or 2 airway was tested. We also evaluated the predictive ability of the Mallampati airway class (1 and 2 vs 3 and 4) along with 9 other possible predictors of difficult intubation on first-attempt intubation success: gender, age, body mass index, level of training within our anesthesia residency program (Clinical Anesthesia Resident years 1, 2, and 3), ASA physical status, mouth opening, thyromental distance, neck flexion, and neck extension.

MAIN RESULTS

None of the standard predictors of difficult intubation was significantly associated with outcome after adjusting for other predictors. A multivariable model containing the aggregate set of variables predicted outcome significantly better than a risk score formed as the sum of 10 predictors ("Risk 10"; P = 0.0176).

CONCLUSIONS

With GlideScope-assisted tracheal intubation, Mallampati airway class is not an independent risk factor for difficult intubation. Other standard clinical risk factors of difficulty with direct laryngoscopy also do not appear to be individually predictive of first-attempt success of tracheal intubation.

Difficult Airway Society Guidelines for the management of tracheal extubation

Tracheal extubation is a high-risk phase of anaesthesia. The majority of problems that occur during extubation and emergence are of a minor nature, but a small and significant number may result in injury or death. The need for a strategy incorporating extubation is mentioned in several international airway management guidelines, but the subject is not discussed in detail, and the emphasis has been on extubation of the patient with a difficult airway. The Difficult Airway Society has developed guidelines for the safe management of tracheal extubation in adult peri-operative practice. The guidelines discuss the problems arising during extubation and recovery and promote a strategic, stepwise approach to extubation. They emphasise the importance of planning and preparation, and include practical techniques for use in clinical practice and recommendations for post-extubation care.

[Emergency anesthesia, airway management and ventilation in major trauma. Background and key messages of the interdisciplinary S3 guidelines for major trauma patients]

Patients with multiple trauma presenting with apnea or a gasping breathing pattern (respiratory rate <6/min) require prehospital endotracheal intubation (ETI) and ventilation. Additional indications are hypoxia (S(p)O(2)<90% despite oxygen insufflation and after exclusion of tension pneumothorax), severe traumatic brain injury [Glasgow Coma Scale (GCS)<9], trauma-associated hemodynamic instability [systolic blood pressure (SBP)<90 mmHg] and severe chest trauma with respiratory insufficiency (respiratory rate >29/min). The induction of anesthesia after preoxygenation is conducted as rapid sequence induction (analgesic, hypnotic drug, neuromuscular blocking agent). With the availability of ketamine as a viable alternative, the use of etomidate is not encouraged due to its side effects on adrenal function. An electrocardiogram (ECG), blood pressure measurement and pulse oximetry are needed to monitor the emergency anesthesia and the secured airway. Capnography is absolutely mandatory to confirm correct placement of the endotracheal tube and to monitor tube dislocations as well as ventilation and oxygenation in the prehospital and hospital setting. Because airway management is often complicated in trauma patients, alternative devices and a fiber-optic endoscope need to be available within the hospital. Use of these alternative measures for airway management and ventilation should be considered at the latest after a maximum of three unsuccessful intubation attempts. Emergency medical service (EMS) physicians should to be trained in emergency anesthesia, ETI and alternative methods of airway management on a regular basis. Within hospitals ETI, emergency anesthesia and ventilation are to be conducted by trained and experienced anesthesiologists. When a difficult airway or induction of anesthesia is expected, endotracheal intubation should be supervised or conducted by an anesthesiologist. Normoventilation should be the goal of mechanical ventilation. After arrival in the resuscitation room the ventilation will be controlled and guided with the help of arterial blood gas analyses. After temporary removal of a cervical collar, the cervical spine needs to be immobilized by means of manual in-line stabilization when securing the airway.

Retrograde tracheal intubation

Summary Successful management of difficult tracheal intubation by retrograde intubation has been reported for almost 50 years and can be used whether or not it is anticipated. There are numerous reports of variations to the basic technique to enhance reproducibility of this guided blind procedure. A review and analysis of the equipment and techniques provides a better understanding of this effective technique.

Videolaryngoscopy in the management of the difficult airway: a comparison with the Macintosh blade

BACKGROUND AND OBJECTIVE

Several studies have shown that videolaryngoscopes can provide better laryngeal exposure than conventional laryngoscopy. These studies, however, did not exclusively focus on patients with an anticipated difficult intubation. The aim of the present study was to assess whether a videolaryngoscope would provide better laryngeal exposure than conventional laryngoscopy and therefore facilitate intubation in cases of difficult laryngoscopy.

METHODS

One hundred and twelve patients with an estimated difficult intubation, scheduled to undergo surgical operations, requiring general anaesthesia and endotracheal intubation, were included in the study. Direct laryngoscopy with a Macintosh blade was performed, followed by videolaryngoscopy and intubation attempt(s). The laryngeal views obtained by each method were recorded according to the Cormack/Lehane scale.

RESULTS

The percentage of Cormack-Lehane I and II views obtained by conventional laryngoscopy rose from 63.4 to 90.2% (P < 0.0005) with videolaryngoscopy, whereas Cormack-Lehane III and IV views declined from 36.6 to 9.8% (P < 0.0005). Intubation was successful in 98.2% of the cases.

CONCLUSION

In patients with an anticipated difficult airway, videolaryngoscopy significantly improved the laryngeal exposure thus facilitating endotracheal intubation.

Retrograde intubation

Airway management in the emergency department is a critical skill that must be mastered by emergency physicians. When rapid-sequence induction with oral-tracheal intubation performed by way of direct laryngoscopy is difficult or impossible due to a variety of circumstances, an alternative method or device must be used for a rescue airway. Retrograde intubation requires little equipment and has few contraindications. This technique is easy to learn and has a high level of skill retention. Familiarity with this technique is a valuable addition to the airway-management armamentarium of emergency physicians caring for ill or injured patients. Variations of the technique have been described, and their use depends on the individual circumstances.