The intubating laryngeal mask airway after induction of general anesthesia versus awake fiberoptic intubation in patients with difficult airways

2022 American Society of Anesthesiologists Practice Guidelines for Management of the Difficult Airway

The American Society of Anesthesiologists; All India Difficult Airway Association; European Airway Management Society; European Society of Anaesthesiology and Intensive Care; Italian Society of Anesthesiology, Analgesia, Resuscitation and Intensive Care; Learning, Teaching and Investigation Difficult Airway Group; Society for Airway Management; Society for Ambulatory Anesthesia; Society for Head and Neck Anesthesia; Society for Pediatric Anesthesia; Society of Critical Care Anesthesiologists; and the Trauma Anesthesiology Society present an updated report of the Practice Guidelines for Management of the Difficult Airway.

Safety and Efficacy of a Novel Intubating Laryngeal Mask during the recovery period following Supratentorial Tumour Surgery

Objective

To assess safety and efficacy of a novel intubation laryngeal mask airway (ILMA) during the recovery period following supratentorial tumour surgery.

Methods

Patients who underwent supratentorial tumour surgery at our centre from January 2012 to December 2016 were eligible for this prospective randomised, parallel group study. We developed a novel ILMA using closely fitting laryngeal masks (No. 4/5) with 7.0/7.5 mm endotracheal tubes (ETT) plus screw fixators and anti-pollution sleeves.

Results

In total, 100 patients were intubated with the novel ILMA and 100 the ETT. There were no differences between groups in haemodynamic variables, oxygen saturation, exhaled CO₂, or bispectral index all recorded during the 72-hour recovery period. However, there were significantly fewer incidences of coughing, less fluid drainage and lower haemoglobin levels in surgical fluid in the ILMA group compared with the ETT group.

Conclusion

Our novel ILMA device was associated with reduced coughing, fluid drainage and blood in surgical drain during the recovery period following supratentorial tumour surgery.

Successful endotracheal intubation using i-gel supraglottic airway device and ultrasonography in a patient with bedside cervical traction: A case report

We report a case of successful endotracheal intubation using i-gel and ultrasonography without a laryngoscope in a patient with a bedside cervical traction device. A 57-year-old man was referred to the emergency department because of quadriparesis following a motor vehicle accident, who was confirmed to have cervical dislocation with spinal cord compression. For ventilation support, the i-gel rescue airway device was placed to secure the patient airway temporarily. Then, an endotracheal tube was passed through the stem of the i-gel while observing the optimal tube position with ultrasonography. This case showed that ultrasonography can be used for early confirmation of endotracheal tube placement into the trachea via the i-gel.

Noninvasive ventilation support during fiberoptic bronchoscopy-guided nasotracheal intubation effectively prevents severe hypoxemia

Purpose

This study investigated the feasibility and efficacy of continuous noninvasive ventilation (NIV) support with 100% oxygen using a specially designed face mask, for reducing desaturation during fiberoptic bronchoscopy (FOB)-guided intubation in critically ill patients with respiratory failure.

Materials and methods

This was a single-center prospective randomized study. All patients undergoing FOB-guided nasal tracheal intubation were randomized to bag-valve-mask ventilation or NIV for preoxygenation followed by intubation. The NIV group were intubated through a sealed hole in a specially designed face mask during continuous NIV support with 100% oxygen. Control patients were intubated with removal of the mask and no ventilatory support.

Results

We enrolled 106 patients, including 53 in each group. Pulse oxygen saturation (SpO₂) after preoxygenation (99% (96%–100%) vs. 96% (90%–99%), p = .001) and minimum SpO₂ during intubation (95% (87%–100%) vs. 83% (74%–91%), p < .01) were both significantly higher in the NIV compared with the control group. Severe hypoxemic events (SpO₂ < 80%) occurred less frequently in the NIV group than in controls (7.4% vs. 37.7%, respectively; p < .01).

Conclusions

Continuous NIV support during FOB-guided nasal intubation can prevent severe desaturation during intubation in critically ill patients with respiratory failure.

Trial registration: ClinicalTrials.gov, NCT02462668. Registered on 25 May 2015, https://www.clinicaltrials.gov/ct2/results?term=NCT02462668.

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Our study is the first to evaluate NIV during FOB-guided nasotracheal intubation.

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NIV support during FOB-guided nasotracheal intubation was effectively prevented severe desaturation during intubation.

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We used a specially-designed intubation face mask to ensure that there was no interruption of NIV support during intubation.

Comparative evaluation of Ambu Aura-i and Fastrach™ intubating laryngeal mask airway for tracheal intubation: A randomized controlled trial

Background and aims:

Ambu Aura-i was compared with Fastrach™ (FT)-laryngeal mask airway (LMA) as a conduit for tracheal intubation.

Material and Methods:

A hundred consenting patients were randomly allocated into two groups of 50 patients each in a prospective randomized study. Standard anesthesia technique was used for all patients and FT-LMA or Ambu Aura-i was selected. After insertion of airway device, the cuff was inflated and ventilation was attempted. Once satisfactory ventilation was achieved, with or without maneuvers, a fiberoptic scoring for glottis view was noted. A polyvinylchloride (PVC) tracheal tube of appropriate size was inserted through the airway device as per procedure. If no resistance was felt while advancing the tracheal tube, it was fully inserted into the device and tracheal tube cuff was inflated. The device was removed and tracheal tube was left in situ. If the first attempt failed during tracheal tube insertion, the recommended maneuvers were used. A maximum of three attempts were allowed for intubation. First attempt for tracheal intubation attempt was a blind, second attempt was made with maneuver. If second attempt of intubation was unsuccessful, fiberoptic-guided intubation was performed as a third attempt. When tracheal intubation was unsuccessful, it was performed by direct laryngoscopy and considered as failed intubation. Rest of the anesthesia management was as per the discretion of attending anesthesiologists. The success rate of device insertion, fiberoptic score of glottis view, tracheal intubation via FT-LMA or Aura-i and time were recorded.

Results:

Both FT-LMA and Aura-i were successfully placed within two attempts. The success rate of blind intubation was 92% in FT-LMA and 76% in Aura-i (P < 0.01). Time taken for tracheal intubation at first attempt was lesser in group FT-LMA and Aura-i, respectively (P < 0.01). Fiberoptic-guided intubation success rate was higher with Aura-i than with FT-LMA.

Conclusions:

FT-LMA had a higher success rate in facilitating blind tracheal intubation compared with Ambu Aura-i.

Guidelines for the management of tracheal intubation in critically ill adults

These guidelines describe a comprehensive strategy to optimize oxygenation, airway management, and tracheal intubation in critically ill patients, in all hospital locations. They are a direct response to the 4^th National Audit Project of the Royal College of Anaesthetists and Difficult Airway Society, which highlighted deficient management of these extremely vulnerable patients leading to major complications and avoidable deaths. They are founded on robust evidence where available, supplemented by expert consensus opinion where it is not. These guidelines recognize that improved outcomes of emergency airway management require closer attention to human factors, rather than simply introduction of new devices or improved technical proficiency. They stress the role of the airway team, a shared mental model, planning, and communication throughout airway management. The primacy of oxygenation including pre- and peroxygenation is emphasized. A modified rapid sequence approach is recommended. Optimal management is presented in an algorithm that combines Plans B and C, incorporating elements of the Vortex approach. To avoid delays and task fixation, the importance of limiting procedural attempts, promptly recognizing failure, and transitioning to the next algorithm step are emphasized. The guidelines recommend early use of a videolaryngoscope, with a screen visible to all, and second generation supraglottic airways for airway rescue. Recommendations for emergency front of neck airway are for a scalpel-bougie-tube technique while acknowledging the value of other techniques performed by trained experts. As most critical care airway catastrophes occur after intubation, from dislodged or blocked tubes, essential methods to avoid these complications are also emphasized.

Evaluation of Fastrach Laryngeal Mask Airway as an Alternative to Fiberoptic Bronchoscope to Manage Difficult Airway: A Comparative Study

INTRODUCTION

Awake intubation via Fiberoptic Bronchoscope (FB) is the gold standard for management of difficult airway but patients had to face problems like oxygen desaturation, tachycardia, hypertension and anxiety due to awake state. This study was conducted to assess feasibility of Fastrach Laryngeal Mask Airway (FLMA) to manage difficult airway as a conduit for intubation as well as for ventilation.

MATERIALS AND METHODS

After ethical approval and informed consent, 60 patients with difficult airway were randomly enrolled in FB group and FLMA group. In FB group, patients were sedated with midazolam/fentanyl. Airway anaesthetization of oropharynx was done with xylocaine spray and viscous and larynx and trachea by superior laryngeal nerve block and transtracheal block respectively. In FLMA group, initially patients were induced with propofol for FLMA insertion then succinylcholine was given for Tracheal Intubation (TI). The first TI attempt was done blindly via the FLMA and all subsequent attempts were performed with fiberoptic guidance. Haemodynamic monitoring was done during induction, intubation, immediately post insertion and there after at five minutes interval for 30 minutes.

RESULTS

All patients in the FLMA group were successfully ventilated (100%). In both the groups 28 (93.33%) patients were successfully intubated. However, first/second/third attempt intubation rate in FLMA vs FB group was 15 (50%) vs 13 (43.3%), 8 (26.66%) vs 10 (33.33%) and 5 (16.66%) in both groups respectively. Patients in the FLMA group were more satisfied with their method of TI and had lesser complications (p<0.05).

CONCLUSION

So the FLMA may be a better technique for management of patients with difficult airways.

The anesthesia of trachea and bronchus surgery

The trachea and bronchus surgery is generally performed due to stenosis, traumatic injury, foreign body and tumors. Preoperative evaluation and anesthesia management are very important issues because of higher mortality and morbidity rates. Patients may be asymptomatic, but airway difficulties, hypoxia, stridor, cough, hemoptysis are common conditions in these patient population. The collaboration between the surgeon and the anesthesiologist is very substantial and necessary. Anesthetic techniques include various applications such as one lung ventilation, fiberoptic intubation, jet ventilation, and apneic oxygenation, general anesthesia with or without neuromuscular blockade. In this review, anesthesia management of the trachea and bronchus surgery is evaluated in the light of new knowledge.

Comparison of an Intraoperative Infusion of Dexmedetomidine, Fentanyl, and Remifentanil on Perioperative Hemodynamics, Sedation Quality, and Postoperative Pain Control

We aimed to compare fentanyl, remifentanil and dexmedetomidine with respect to hemodynamic stability, postoperative pain control and achievement of sedation at the postanesthetic care unit (PACU). In this randomized double-blind study, 90 consecutive total laparoscopic hysterectomy patients scheduled for elective surgery were randomly assigned to receive fentanyl (1.0 μg/kg) over 1 minute followed by a 0.4 μg/kg/hr infusion (FK group, n = 30), or remifentanil (1.0 μg/kg) over 1 minute followed by a 0.08 μg/kg/min infusion (RK group, n = 30), or dexmedetomidine (1 μg/kg) over 10 minutes followed by a 0.5 μg/kg/hr infusion (DK group, n = 30) initiating at the end of main procedures of the operation to the time in the PACU. A single dose of intravenous ketorolac (30 mg) was given to all patients at the end of surgery. We respectively evaluated the pain VAS scores, the modified OAA/S scores, the BIS, the vital signs and the perioperative side effects to compare the efficacy of fentanyl, remifentanil and dexmedetomidine. Compared with other groups, the modified OAA/S scores were significantly lower in DK group at 0, 5 and 10 minutes after arrival at the PACU (P < 0.05), whereas the pain VAS and BIS were not significantly different from other groups. The blood pressure and heart rate in the DK group were significantly lower than those of other groups at the PACU (P < 0.05). DK group, at sedative doses, had the better postoperative hemodynamic stability than RK group or FK group and demonstrated a similar effect of pain control as RK group and FK group with patient awareness during sedation in the PACU. (World Health Organization registry, KCT0001524).

Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults

These guidelines provide a strategy to manage unanticipated difficulty with tracheal intubation. They are founded on published evidence. Where evidence is lacking, they have been directed by feedback from members of the Difficult Airway Society and based on expert opinion. These guidelines have been informed by advances in the understanding of crisis management; they emphasize the recognition and declaration of difficulty during airway management. A simplified, single algorithm now covers unanticipated difficulties in both routine intubation and rapid sequence induction. Planning for failed intubation should form part of the pre-induction briefing, particularly for urgent surgery. Emphasis is placed on assessment, preparation, positioning, preoxygenation, maintenance of oxygenation, and minimizing trauma from airway interventions. It is recommended that the number of airway interventions are limited, and blind techniques using a bougie or through supraglottic airway devices have been superseded by video- or fibre-optically guided intubation. If tracheal intubation fails, supraglottic airway devices are recommended to provide a route for oxygenation while reviewing how to proceed. Second-generation devices have advantages and are recommended. When both tracheal intubation and supraglottic airway device insertion have failed, waking the patient is the default option. If at this stage, face-mask oxygenation is impossible in the presence of muscle relaxation, cricothyroidotomy should follow immediately. Scalpel cricothyroidotomy is recommended as the preferred rescue technique and should be practised by all anaesthetists. The plans outlined are designed to be simple and easy to follow. They should be regularly rehearsed and made familiar to the whole theatre team.

A comparison of fibreoptic-guided tracheal intubation through the Ambu ® Aura-i ™, the intubating laryngeal mask airway and the i-gel ™: a manikin study

We compared the Aura-i(™) , intubating laryngeal mask airway and i-gel(™) as conduits for fibreoptic-guided tracheal intubation in a manikin. Thirty anaesthetists each performed two tracheal intubations through each device, a total of 180 intubations. The median (IQR [range]) time to complete the first intubation was 40 (31-50 [15-162]) s, 37 (34-48 [25-75]) s and 28 (22-35 [14-59]) s for the Aura-i, intubating laryngeal mask airway and i-gel, respectively. Tracheal intubation through the i-gel was the quickest (p < 0.01). Resistance to railroading of the tracheal tube over the fibrescope was significantly greater through the Aura-i compared with the intubating laryngeal mask airway and the i-gel (p = 0.001). There were no failures to intubate through the intubating laryngeal mask airway or the i-gel but six intubation attempts through the Aura-i were unsuccessful, in five owing to a railroading failure and in one owing to accidental oesophageal intubation. We conclude that the Aura-i does not perform as well as the intubating laryngeal mask airway or the i-gel as an adjunct for performing fibreoptic-guided tracheal intubation.

Shikani optical stylet-guided intubation via the intubating laryngeal airway in patients with scar contracture of the face and neck

OBJECTIVE

To evaluate the feasibility of the Shikani Optical Stylet (SOS)-guided intubation through a new Intubating Laryngeal Airway (ILA) in anticipated difficult airways caused by scar contracture of the face and neck.

METHODS

Thirty-three adult patients with anticipated difficult airways undergoing selective faciocervical scar plastic surgery under general anesthesia were enrolled in this study. After anesthesia induction, a size 2.5, 3.5 or 4.5 ILA was inserted. Following good lung ventilation being verified, the SOS preloaded with an endotracheal tube was inserted via the ILA. Once the clear vocal cords came into view under the SOS, the endotracheal tube was advanced through glottis into the trachea.

RESULTS

The ILA provided an effective airway in all patients. Intubation was successful at the first attempt on 22/33(66.7%) occasions and at the second attempt on 6/33 (18.2%). Intubation failed in 5 (15.1%) patients who suffered from severe limitation of head extension due to scar contracture of the neck. These patients' tracheas were finally intubated using a fibreoptic bronchoscope via the ILA.

CONCLUSIONS

The SOS-guided intubating method via the ILA is a feasible technique in patients with scar contracture of the face and neck. However, in patients with severe limitation of head extension, the use of SOS cannot be recommended. The SOS can be used as an alternative apparatus when the fibreoptic bronchoscope is not available.

Endotracheal intubation with intubating laryngeal mask airway (ILMA), C-Trach, and Cobra PLA in simulated cervical spine injury patients: a comparative study

PURPOSE

The aim of our study was to evaluate the success rate of fiberoptic-guided endotracheal intubation through an Intubating Laryngeal Mask Airway (ILMA), a Cobra Perilaryngeal Airway (Cobra PLA), and a C-Trach Laryngeal Mask Airway (C-Trach) in patients whose necks are stabilized in a hard cervical collar.

METHODS

One hundred and eighty ASA I-II patients were randomized to undergo endotracheal intubation after general anesthesia via an ILMA (group ILMA), a C-Trach (group C-Trach) or a Cobra PLA (group CPLA) with the application of an appropriately-sized hard cervical collar. A fiberoptic bronchoscope was used for intubation via the ILMA and Cobra PLA. Rate of successful insertion of an endotracheal tube through the three devices was the primary aim. Other parameters compared were time taken for device insertion, endotracheal intubation, hemodynamic changes, incidence of hypoxia, and mucosal injury during the procedure. The incidence of postoperative sore throat was also compared between the three groups.

RESULTS

The success rates of intubation in the ILMA, C-Trach, and CPLA groups were 100, 100, and 98% respectively. The first-attempt success rate was significantly better with the C-Trach compared to Cobra PLA (100 vs. 85%, p < 0.05). The time taken for device insertion was significantly more with the Cobra PLA as compared to that taken with an ILMA or a C-Trach (35.7 vs. 30.3 and 27.5 s, respectively). Intubation through a C-Trach took the least amount of time (84.4 s) as compared to an ILMA (117.9 s) or a Cobra PLA (139.2 s). The incidence of hypoxia and airway morbidity was similar between the groups.

CONCLUSION

The success rates of fiberoptic-guided endotracheal intubation through an ILMA and a Cobra PLA are similar to the success rate of intubation using a C-Trach in patients whose cervical spines are immobilized with a hard cervical collar.

Tracheal intubation with a flexible intubation scope versus other intubation techniques for obese patients requiring general anaesthesia

BACKGROUND

The prevalence of obesity (body mass index (BMI) > 30 kg/m(2)) is increasing in both developed and developing countries, leading to a rise in the numbers of obese patients requiring general anaesthesia. Obese patients are at increased risk of anaesthetic complications, and tracheal intubation can be more difficult. Flexible intubation scopes (FISs) are recommended as an alternative method of intubation in these patients. Intubation with an FIS is considered an advanced method, requiring training and experience; therefore it may be underused in clinical practice. Patient outcomes following intubation with these scopes compared with other devices have not been systematically reviewed.

OBJECTIVES

We wished to compare the safety and effectiveness of a flexible intubation scope (FIS) used for tracheal intubation in obese patients (BMI > 30 kg/m(2)) with other methods of intubation, including conventional direct laryngoscopy, non-standard laryngoscopy and the use of intubating supraglottic airway devices. We aimed to compare the frequency of complications, as well as process indicators, such as time taken for intubation and the proportion of first attempts that were successful, between groups using the different methods of intubation.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and two trial registers on 18 January 2013, and performed reference checking and citation searching and contacted study authors to identify additional studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of participants aged 16 years and older with a BMI > 30 kg/m(2) that had compared the use of an FIS for tracheal intubation with any one of three comparison groups: direct laryngoscopy; non-standard laryngoscopy (including indirect laryngoscopy using a videolaryngoscope (VLS) or a rigid or semi-rigid stylet); or intubation of supraglottic airway devices (SADs).

DATA COLLECTION AND ANALYSIS

We used standard methodological approaches expected by The Cochrane Collaboration, including independent review of titles, data extraction and risk of bias assessment by two investigators.

MAIN RESULTS

Three eligible studies were identified, all comparing the use of an FIS with a VLS. All studies were small, with only 131 participants in total across all trials. It was impossible for the intubators to be unaware of the device used, so all studies were at high risk of performance and detection bias for outcomes related to intubation. Because of substantial differences in design between the studies, we did not combine their results in meta-analyses. The results for all outcomes were inconclusive, with no differences noted between FIS and VLS. Two studies with experienced intubators reported first attempt success rates greater than 70% in both groups and less than 5% of participants requiring a change of intubation device. No evidence was found of any difference in difficulty or time taken between FIS and VLS intubation. No serious complications or airway trauma was reported, so we were unable to address these outcomes. Bleeding was uncommon, occurring in less than 5% of participants, and we found no evidence that it was more likely in the FIS group. One small study with a novice intubator reported no successful intubations using an FIS and compared with the use of an intubating SAD and stylet, as well as with a VLS. With only five participants in each group, no conclusions can be drawn from these additional comparisons.

AUTHORS' CONCLUSIONS

The evidence base is sparse, and the existing literature does not address the clinical questions of patient safety posed by this review. We are therefore unable to draw any conclusions on safety or effectiveness. More primary research is needed to investigate optimal intubation techniques in obese patients, and new studies should be powered to detect differences in complications and in success rates rather than process measures such as speed, which are of limited clinical importance.

The difficult airway with recommendations for management--part 2--the anticipated difficult airway

BACKGROUND

Appropriate planning is crucial to avoid morbidity and mortality when difficulty is anticipated with airway management. Many guidelines developed by national societies have focused on management of difficulty encountered in the unconscious patient; however, little guidance appears in the literature on how best to approach the patient with an anticipated difficult airway.

METHODS

To review this and other subjects, the Canadian Airway Focus Group (CAFG) was re-formed. With representation from anesthesiology, emergency medicine, and critical care, CAFG members were assigned topics for review. As literature reviews were completed, results were presented and discussed during teleconferences and two face-to-face meetings. When appropriate, evidence- or consensus-based recommendations were made, and levels of evidence were assigned.

PRINCIPAL FINDINGS

Previously published predictors of difficult direct laryngoscopy are widely known. More recent studies report predictors of difficult face mask ventilation, video laryngoscopy, use of a supraglottic device, and cricothyrotomy. All are important facets of a complete airway evaluation and must be considered when difficulty is anticipated with airway management. Many studies now document the increasing patient morbidity that occurs with multiple attempts at tracheal intubation. Therefore, when difficulty is anticipated, tracheal intubation after induction of general anesthesia should be considered only when success with the chosen device(s) can be predicted in a maximum of three attempts. Concomitant predicted difficulty using oxygenation by face mask or supraglottic device ventilation as a fallback makes an awake approach advisable. Contextual issues, such as patient cooperation, availability of additional skilled help, and the clinician's experience, must also be considered in deciding the appropriate strategy.

CONCLUSIONS

With an appropriate airway evaluation and consideration of relevant contextual issues, a rational decision can be made on whether an awake approach to tracheal intubation will maximize patient safety or if airway management can safely proceed after induction of general anesthesia. With predicted difficulty, close attention should be paid to details of implementing the chosen approach. This should include having a plan in case of the failure of tracheal intubation or patient oxygenation.

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

Background

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

Methods

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

Conclusions

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

Difficult airway intubation with flexible bronchoscope

BACKGROUND AND OBJECTIVE

To describe the efficacy and safety of a flexible bronchoscopy intubation (FBI) protocol in patients with difficult airway.

METHOD

We reviewed the medical records of patients diagnosed with difficult airway who underwent flexible bronchoscopy intubation under spontaneous ventilation and sedation with midazolam and fentanyl from March 2009 to December 2010.

RESULTS

The study enrolled 102 patients, 69 (67.7%) men and 33 (32.3%) women, with a mean age of 44 years. FBI was performed in 59 patients (57.8%) with expected difficult airway in the operating room, in 39 patients (38.2%) in the Intensive Care Unit (ICU), and in 4 patients (3.9%) in the emergency room. Cough, decrease in transient oxygen saturation, and difficult progression of the cannula through the larynx were the main complications, but these factors did not prevent intubation.

CONCLUSION

FBI according to the conscious sedation protocol with midazolam and fentanyl is effective and safe in the management of patients with difficult airway.

Conscious sedation for awake fibreoptic intubation: a review of the literature

PURPOSE

Awake fibreoptic intubation (AFOI) is the gold standard of management of the predicted difficult airway. Sedation is frequently used to make the process more tolerable to patients. It is not always easy to strike a balance between patient comfort and good intubating conditions on the one hand and maintaining ventilation and a patent airway on the other. In the last 30 years, many drugs and drug combinations have been described, but there is very little in the literature to help guide the practitioner to choose between them. The objective of this article is to discuss the evidence supporting the use of the agents described with regard to their efficacy, recommended doses and techniques, and limitations to their use for AFOI.

SOURCE

Publication databases were searched for articles published from 1996 to 2012 relating to sedation for AFOI.

PRINCIPLE FINDINGS

Benzodiazepines, propofol, opioids, alpha2-adrenoceptor agonists, and ketamine are the main classes of drugs that have been described to facilitate AFOI. Drugs that are most suitable have a combination of both anxiolytic and analgesic properties. The ideal choice of drug may vary depending on the patient and the indication for AFOI.

CONCLUSION

There is good evidence to support the use of two drugs in particular, remifentanil and dexmedetomidine. Each has certain unique characteristics that make them an attractive choice for an AFOI.

Use of video-assisted intubation devices in the management of patients with trauma

Patients with trauma may have airways that are difficult to manage. Patients with blunt trauma are at increased risk of unrecognized cervical spine injury, especially patients with head trauma. Manual in-line stabilization reduces cervical motion and should be applied whenever a cervical collar is removed. All airway interventions cause some degree of cervical spine motion. Flexible fiberoptic intubation causes the least cervical motion of all intubation approaches, and rigid video laryngoscopy provides a good laryngeal view and eases intubation difficulty. In emergency medicine departments, video laryngoscopy use is growing and observational data suggest an improved success rate compared with direct laryngoscopy.

Airway management in neuroanesthesiology

Airway management for neuroanesthesiology brings together some key principles that are shared throughout neuroanesthesiology. This article appropriately targets the cervical spine with associated injury and the challenges surrounding airway management. The primary focus of this article is on the unique airway management obstacles encountered with cervical spine injury or cervical spine surgery, and unique considerations regarding functional neurosurgery are addressed. Furthermore, topics related to difficult airway management for those with rheumatoid arthritis or pituitary surgery are reviewed.

Airway management practices in adult intensive care units in Israel: a national survey

Timely and adequate management of normal and compromised airway is a crucial task facing medical teams taking care of patients in intensive care units. We investigated the airway management practices in the Israeli intensive care units (ICUs). A postal survey was sent to the 20 main ICUs in Israel. We investigated which medical specialty (ICU, anesthesiology or ENT) is involved with airway management in the ICUs and summarized the availability of airway equipment and medication necessary for endotracheal intubation, the use of dedicated airway management algorithms, the approaches to specific airway scenarios and education in airway management. The response rate was 70 % (14 out of the 20 units). Intubation with normal airway is performed mainly by ICU doctors (86 %). A difficult airway is most frequently cared for by anesthesiologists (79 %), while impossible intubation/mask ventilation is mainly managed by anesthesiologists and ENT surgeons (50-79 %). Airways in C-spine injury are mainly managed by anesthesiologists (70 %). Surgical airway is mainly performed by ENT surgeons (79 %). The ASA difficult airway algorithm is used in 71 % of the units. Fiberoptic intubation is used significantly more often than other methods in two scenarios: 78 % of the difficult airways and 64 % of the C-spine injuries (p < 0.0001). Only 43 % of the units reported holding quality assurance meetings. 69 % of the units' heads are satisfied with their airway management policies. Equipment and medications necessary for airway management are available in most of the units. Difficult airways in ICUs are mainly managed by anesthesiologists and ENT surgeons. Few ICUs have quality assurance meetings.

Comparison of an Intraoperative Infusion of Dexmedetomidine or Remifentanil on Perioperative Haemodynamics, Hypnosis and Sedation, and Postoperative Pain Control

This prospective, randomized, double-blind study compared the effects of dexmedetomidine and remifentanil on haemodynamic stability, sedation and postoperative pain control in the postanaesthetic care unit (PACU). Fifty consecutive patients scheduled for total laparoscopic hysterectomy were randomly assigned to receive infusions of either dexmedetomidine (1 μg/kg) i.v. over 10 min followed by 0.2-0.7 μg/kg per h continuous i.v. infusion or remifentanil (0.8-1.2 μg/kg) i.v. over 1 min followed by 0.05-0.1 μg/kg i.v. per min, starting at the end of surgery to the time in the PACU. Modified observer's assessment of alertness scores were significantly lower in the dexmedetomidine group than in the remifentanil group at 0, 5 and 10 min after arrival in the PACU. Blood pressure and heart rate in the dexmedetomidine group were significantly lower than that recorded in the remifentanil group in the PACU. Dexmedetomidine, at the doses used in this study, had a significant advantage over remifentanil in terms of postoperative haemodynamic stability.

The Fastrach Intubating Laryngeal Mask Airway: an overview and update

PURPOSE

To provide an evidence-based overview and update on the use of the Fastrach Intubating Laryngeal Mask Airway (FT-LMA) when used within operative and non-operative settings.

PRINCIPAL FINDINGS

The FT-LMA is available in three sizes to provide ventilation and the ability to pass an endotracheal tube (ETT) into the trachea blindly, semi-blindly, or with indirect visualization for patients over 30 kg. The Chandy maneuver is recommended routinely; the first maneuver optimizes ventilation, and the second maneuver increases success at endotracheal intubation (ETI). The manufacturer's reinforced tube or a pre-warmed or reversed standard ETT may be utilized. Insertion and ventilation are successful in almost all patients. Blind ETI is highly successful; adjuncts are generally not necessary. The FT-LMA has a proven role in the airway management of anticipated difficult operating room (OR) intubations, unanticipated OR intubations, cervical spine injuries, and limited airway access situations. Literature in the pre-hospital and emergency department settings is limited but favourable. The FT-LMA has compared favourably with fibreoptic intubation, the LMA-Classic, the laryngeal tube, and the CobraPLA. Initially, the more expensive LMA CTrach appeared to be more successful, but overall it is not. The FT-LMA airway seal pressures are excellent; serious complications are uncommon, and the FT-LMA figures prominently in most difficult airway guidelines.

CONCLUSIONS

The FT-LMA has proven to be a useful difficult airway device both within and outside of the operating room. Effective ventilation is established in nearly all cases, and blind ETI is possible in the vast majority of cases if the optimal techniques described are used. Serious complications are uncommon.

Airway management in patients

Stridor is caused by turbulent flow through a narrow airway. Common causes of stridor are deep neck infection, malignancy, angioneurotic oedema, trauma and congenital anomalies like laryngomalacia. The majority of these conditions can progress rapidly to complete airway obstruction. These conditions are traditionally managed with one of the following techniques: inhalational induction, awake tracheostomy, awake fibreoptic intubation or blind nasal intubation. The success and safety of each of these techniques continues to be debated.

Spray-as-you-go airway topical anesthesia in patients with a difficult airway: a randomized, double-blind comparison of 2% and 4% lidocaine

BACKGROUND

We designed this randomized, double-blind clinical study to compare the safety and efficacy of 2% and 4% lidocaine during airway topical anesthesia with a spray-as-you-go technique via the fiberoptic bronchoscope.

METHODS

Fifty-two adult patients with a difficult airway were randomly assigned to 1 of 2 study groups to receive 2% (Group 1) or 4% lidocaine (Group 2) by a spray-as-you-go technique with the fiberoptic bronchoscope, in a double-blind manner. After airway topical anesthesia, awake fiberoptic orotracheal intubation (FOI) was performed. Level of sedation, time for each lidocaine spray in different targeted areas, total times for airway sprays, total dosages of lidocaine used for airway sprays, intubation times, and number of intubation attempts were noted. An independent investigator scored patients' comfort during airway topical anesthesia, patients' reaction, coughing severity, and intubating condition during awake FOI, and observed changes of arterial blood pressure and heart rate during each stage in the airway manipulation process. Serial blood samples were obtained for analysis of plasma lidocaine concentrations.

RESULTS

Except for the total dosages and plasma concentrations of lidocaine, there were no significant differences in any of the observed variables between groups. All patients exhibited excellent or acceptable intubating conditions. The total dosages of lidocaine were significantly smaller in Group 1 (3.4 +/- 0.6 mg/kg) than in Group 2 (7.1 +/- 2.1 mg/kg). The plasma lidocaine concentrations in all observed points after the supraglottic sprays were larger in Group 2 than in Group 1.

CONCLUSIONS

Both 2% and 4% lidocaine administered topically by a spray-as-you-go technique can provide clinically acceptable intubating conditions for awake FOI in sedated patients with a difficult airway. As compared with 4% lidocaine, however, 2% lidocaine requires a smaller dosage and results in lower plasma concentrations.

The difficult airway in adult critical care

INTRODUCTION

The difficult airway is a common problem in adult critical care patients. However, the challenge is not just the establishment of a safe airway, but also maintaining that safety over days, weeks, or longer.

AIMS

This review considers the management of the difficult airway in the adult critical care environment. Central themes are the recognition of the potentially difficult airway and the necessary preparation for (and management of) difficult intubation and extubation. Problems associated with tracheostomy tubes and tube displacement are also discussed.

RESULTS

All patients in critical care should initially be viewed as having a potentially difficult airway. They also have less physiological reserve than patients undergoing airway interventions in association with elective surgery. Making the critical care environment as conducive to difficult airway management as the operating room requires planning and teamwork. Extubation of the difficult airway should always be viewed as a potentially difficult reintubation. Tube displacement or obstruction should be strongly suspected in situations of new-onset difficult ventilation.

CONCLUSIONS

Critical care physicians are presented with a significant number of difficult airway problems both during the insertion and removal of the airway. Critical care physicians need to be familiar with the difficult airway algorithms and have skill with relevant airway adjuncts.

Endotracheal Intubation with Flexible Fiberoptic Bronchoscopy in Patients with Abnormal Anatomic Conditions of the Head and Neck

We performed a retrospective chart review to evaluate the indications for endotracheal intubation via flexible fiberoptic bronchoscopy in patients who were scheduled for surgery or who were hospitalized in the intensive care unit of our 1,100-bed, tertiary care university hospital. We reviewed 9,201 clinical records of anesthetic procedures during which endotracheal intubation had been performed from January to December 2002. We identified 66 patients who had been intubated with flexible fiberoptic bronchoscopy. On preanesthetic examination, 61 of these patients had been found to be poor candidates for conventional laryngoscopic intubation—51 because of abnormal head and neck anatomy and 10 because of reduced visual access to the airway (Mallampati class IV). The remaining 5 patients were intubated via flexible fiberoptic bronchoscopy after conventional intubation had failed during emergency surgery. Our study emphasizes (1) the importance of the preanesthetic examination of surgical patients, to identify those in whom conventional intubation would likely be problematic, and (2) the need to have fiberoptic bronchoscopes and an anesthesiologist or bronchoscopist skilled in their use available in operating suites and intensive care units.

Pressure support ventilation during fibreoptic intubation under propofol anaesthesia †

GOAL OF THE STUDY

To assess the benefit of pressure support ventilation during fibreoptic intubation performed under propofol anaesthesia in patients having an anticipated difficult intubation.

PROCEDURES

Thirty-two patients with ENT cancer, and having at least two criteria for anticipated difficult intubation were prospectively included. All patients received topical lidocaine 2% and propofol by plasma target control infusion (initial target concentration 3 microg ml(-1), then adjusted to maintain loss of consciousness without apnoea). They were randomly assigned between two groups: spontaneous breathing (SB) or pressure support ventilation (with a support level set at 10 cm H(2)O) both using Fi(o(2))=1. Conditions for fibreoptic intubation, respiratory parameters (pulse oxymetry, ventilatory frequency, tidal volume and PetCO2 after intubation) and haemodynamic parameters were recorded.

RESULTS

Patient characteristic data and intubation conditions were similar between both groups. All patients had a successful fibreoptic intubation and none needed a rescue procedure because of desaturation. In spite of a longer duration of intubation, PE'CO2 after intubation was lower and tidal volume during intubation was higher with pressure support ventilation than in SB patients [38.1 (4.2) vs 42.3 (4.7) mm Hg and 371 (139) vs 165 (98) ml, respectively]. Desaturation episodes were observed in two SB patients conversely to no episode during pressure support ventilation, probably because of the higher minute ventilation.

CONCLUSION

Pressure support represents a useful method to improve ventilation during fibreoptic intubation under propofol anaesthesia in patients with an anticipated difficult intubation.

Fibre-optic intubation teaching in sedated patients with anticipated difficult intubation

BACKGROUND AND OBJECTIVES

The objective of the study was to assess the safety of training fibre-optic intubation performed under propofol light general anaesthesia in patients with an anticipated difficult intubation.

METHODS

Patients with ear, nose and throat cancer having at least two criteria for anticipated difficult intubation and scheduled for fibre-optic intubation were included prospectively. In 26 patients, intubation was performed by an anaesthesia resident (under senior supervision), whereas in 20 patients, it was performed by a senior anaesthesiologist. All patients received propofol light general anaesthesia adjusted to maintain both loss of consciousness and spontaneous ventilation.

RESULTS

Of the 46 patients, 45 had successful fibre-optic intubation, and one needed a rescue procedure because of hypoxaemia. Residents failed to intubate four patients, who were easily intubated by the senior. Episodic hypoxaemia (SPO2 < 90%) occurred in three patients in each group. No statistically significant difference was found between junior and senior neither on the duration of the procedure (9.3 +/- 4.9 vs. 7.5 +/- 4.0 min) nor on the propofol consumption (197 +/- 130 vs. 193 +/- 103 mg) or the ETCO2 at the end of the procedure (36 +/- 6 vs. 38 +/- 6 mmHg), respectively.

CONCLUSION

Teaching fibre-optic tracheal intubation in patients with anticipated difficult intubation and sedated with propofol did not increase morbidity significantly compared with an experienced anaesthesiologist. Fibre-optic intubation under propofol light general anaesthesia could be safely performed by a resident as long as a senior anaesthesiologist is permanently present, spontaneous ventilation is maintained and a rescue oxygenation technique is immediately available.

Management of unexpected difficult airway at a teaching institution over a 7-year period

STUDY OBJECTIVE

To review an anesthesiology department's experience with managing unexpected difficult airways over a 7-year time span.

DESIGN

Retrospective review of unexpected difficult airway reporting forms.

SETTING

A tertiary care teaching hospital.

PATIENTS

447 patients who had an unanticipated difficult airway and had a difficult airway form filled out by their anesthesiologist.

MEASUREMENTS

Retrospective identification of pertinent physical features associated with difficult intubation was noted. The techniques chosen, their success, and the frequency with which the different advanced airway techniques were chosen was reviewed.

MAIN RESULTS

An anterior larynx was the most common anatomical feature associated with difficult laryngoscopy. When a laryngeal mask airway was placed in our patients, ventilation was possible in all patients. Intubation was successfully "blindly" achieved (ie, without the use of a fiberoptic bronchoscope) through the laryngeal mask airway in 52% of these patients. Fiberoptic intubation was unsuccessful in intubating approximately 10% of patients. The Bullard laryngoscope was the most common advanced airway technique chosen at our institution.

CONCLUSION

Mastery with a number of advanced airway techniques should be sought, as multiple modalities may be needed when faced with managing an unexpectedly difficult airway. Formal written communication to the patient of an unexpected difficult airway encounter may allow future anesthesiologists to formulate an appropriate plan for patient care.

Fiberoptic techniques

Fiberoptic intubation of the spontaneously breathing patient is the gold standard and technique of choice for the elective management of a difficult airway. In the hands of the properly trained and experienced user, it is also an excellent 'plan B' alternative when direct laryngoscopy unexpectedly fails. Fiberscope-assisted intubation through an endoscopy face mask, laryngeal mask airway or intubating laryngeal mask airway secures ventilation and oxygenation, and permits endotracheal intubation in airway emergency situations. Portable fiberscopes can be used in remote settings, increasing patient safety. This review discusses current fiberoptic intubation techniques and their applications in the management of both the anticipated and unanticipated difficult airway.