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

Perioperative management of a patient with Coffin-Lowry syndrome complicated by severe obesity: A case report and literature review

RATIONALE

Coffin-Lowry syndrome (CLS) is a rare inherited disease with specific clinical features, such as mental retardation, facial dysmorphism, and cardiac abnormality. In particular, the characteristic facial features of CLS, including retrognathia and large tongue, are associated with difficult ventilation and/or intubation, which is a serious problem of anesthesia management. However, case reports on anesthesia management of CLS are very limited as there are only two published English reports till date. In this case report, we discuss anesthetic and postoperative considerations in patients with CLS, focusing on difficult airway management, and summarize past reports including some Japanese articles.

PATIENT CONCERNS

A 25-year-old man with CLS was planning to undergo laminectomy because of progressive quadriplegia caused by calcification of the yellow ligament. We suspected difficulty in airway management because of several factors in his facial features, short thyromental and sternomental distances in computed tomography, severe obesity, and sleep apnea syndrome.

DIAGNOSES

Difficult airway was suspected. However, because of mental retardation, awake intubation was considered difficult.

INTERVENTIONS

We selected bronchofiberscope-guided nasotracheal intubation, maintaining spontaneous breathing under moderate sedation with a propofol target-controlled infusion.

OUTCOMES

Airway management was safely performed during anesthesia induction.

LESSONS

In many patients with CLS, difficult intubation was reported, and sedation or slow induction maintaining spontaneous breathing was mainly selected for anesthesia induction. Spontaneous breathing should be maintained during anesthesia induction in case of CLS patients.

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.

Influence of lateral position and pneumoperitoneum on oropharyngeal leak pressure with two types of laryngeal mask airways

BACKGROUND

An important parameter to monitor adequate ventilation for laryngeal mask airway (LMA) is its oropharyngeal leak pressure (OLP). This study was designed to evaluate and compare the effect of lateral position and pneumoperitoneum on the OLP and ventilation efficiency between LMA™ Proseal (PLMA) and LMA™ Supreme (SLMA).

METHODS

Patients were randomized to receive either the PLMA or the SMLA. The OLP was assessed in both the supine position and the lateral position with or without pneumoperitoneum. Minute ventilation was increased to maintain normal EtCO₂ as far as possible. Ventilatory efficiency was scored as Class I (optimal, EtCO₂ 35-45 mmHg), Class II (suboptimal, EtCO₂ 45-55 mmHg) and Class III (poor, EtCO₂ >55 mmHg). Adverse events associated with LMA such as blood staining on the mask and sore throat were also recorded.

RESULTS

Within each group, the OLP was higher in the supine position than that in the lateral position with or without pneumoperitoneum (P < 0.01). However, pneumoperitoneum did not further decrease the OLP. The OLP with PLMA was higher compared with SLMA regardless of the position and pneumoperitoneum (P < 0.05 or 0.01). There was no significant difference in the number of patients in Class I/II/III for ventilation scores in the lateral position with pneumoperitoneum (83/7/2 in PLMA group and 76/14/2 in SLMA group, respectively). The incidence of adverse events was comparable in both groups.

CONCLUSION

Our data demonstrate that the PLMA has a higher OLP in comparison with the SLMA in the lateral position for laparoscopic surgery. Both devices provide comparably adequate ventilatory efficiency.

Airway emergencies presenting to the paediatric emergency department requiring advanced management techniques

BACKGROUND

Airway emergencies presenting to the emergency department (ED) are usually managed with conventional equipment and techniques. The patient group managed urgently in the operating room (OR) has not been described.

AIMS

This study aims to describe a case series of children presenting to the ED with airway emergencies managed urgently in the OR, particularly the anaesthetic equipment and techniques used and airway findings.

METHODS

A retrospective cohort study undertaken at The Royal Children's Hospital, Melbourne, Australia. All patients presenting to the ED between 1 January 2012 and 30 July 2015 (42 months) with an airway emergency who were subsequently managed in the OR were included. Patient characteristics, anaesthetic equipment and technique and airway findings were recorded.

RESULTS

Twenty-two airway emergencies in 21 patients were included over the study period, on average one every 2 months. Median age was 18 months and 43% were male. Inhalational induction was used in 77.3%, combined inhalational and intravenous induction in 9.1%, and intravenous induction alone in 13.6%. The most commonly used inhalational induction agent was sevoflurane, and the most commonly used intravenous induction agents were ketamine and propofol. Ten airway emergencies did not require intubation, seven for removal of inhaled foreign body, two with progressive tracheal stenosis requiring emergent dilatation and one examination under anaesthesia to rule out inhaled foreign body. Of the 12 airway emergencies that required immediate intubation, direct laryngoscopy was used in 9 and fibre-optic intubating bronchoscopy in 3. For intubations performed by direct laryngoscopy, one was difficult (Cormack and Lehane grade 3). First pass success was 83.3%. Adverse events occurred in 3/22 (13.6%) cases.

CONCLUSION

Advanced airway techniques, including inhalational induction and intubation via fibre-optic intubating bronchoscope, are rarely but predictably required in the management of patients presenting to the ED. Institutions caring for children should prepare in advance where such patients should be managed, by whom, and provide equipment and training for their care.

Management of Patients with Predicted Difficult Airways in an Academic Emergency Department

BACKGROUND

Patients with difficult airways are sometimes encountered in the emergency department (ED), however, there is a little data available regarding their management.

OBJECTIVES

To determine the incidence, management, and outcomes of patients with predicted difficult airways in the ED.

METHODS

Over the 1-year period from July 1, 2015 to June 30, 2016, data were prospectively collected on all patients intubated in an academic ED. After each intubation, the operator completed an airway management data form. Operators performed a pre-intubation difficult airway assessment and classified patients into routine, challenging, or difficult airways. All non-arrest patients were included in the study.

RESULTS

There were 456 patients that met inclusion criteria. Fifty (11%) had predicted difficult airways. In these 50 patients, neuromuscular blocking agents (NMBAs) were used in 40 (80%), an awake intubation technique with light sedation was used in 7 (14%), and no medications were used in 3 (6%). In the 40 difficult airway patients who underwent NMBA facilitated intubation, a video laryngoscope (GlideScope 21, Verathon, Bothell, WA and C-MAC 19, Karl Storz, Tuttlingen, Germany) was used in each of these, with a first-pass success of 90%. In the 7 patients who underwent awake intubation, a video laryngoscope was used in 5, and a flexible fiberoptic scope was used in 2. Ketamine was used in 6 of the awake intubations. None of these difficult airway patients required rescue with a surgical airway.

CONCLUSIONS

Difficult airways were predicted in 11% of non-arrest patients requiring intubation in the ED, the majority of which were managed using an NMBA and a video laryngoscope with a high first-pass success.

CXC Chemokine Receptor Type 4 Antagonism Ameliorated Allograft Fibrosis in Rat Kidney Transplant Model

OBJECTIVES

In this study, we evaluated the effects of CXC chemokine receptor type 4 and stromal cell-derived factor 1 signaling in the progression of chronic allograft nephropathy in a rat model.

MATERIALS AND METHODS

Experimental rats were divided into 3 groups: Lewis-to-Lewis isograft transplant (group A), Fisher 344 rat-to-Lewis allograft transplant with immunosuppressant cyclosporine (group B), and Fisher 344 rat-to-Lewis allograft transplant treated with cyclosporine and the CXC chemokine receptor type 4 antagonist AMD3100 (1 mg/kg/d) (group C). On day 90 after the operation, renal graft function, proteinuria, and histologic Banff score were measured. The expression levels of transforming growth factor β1 and collagen IV were determined by quantitative real-time polymerase chain reaction.

RESULTS

Renal function and urinary protein were increased in allografts of groups B and C compared with isografts of group A. The Banff score was significantly decreased in the AMD3100-treated animals (group C), with renal fibrosis being reduced. In addition, overexpressed levels of transforming growth factor β1 and collagen IV in group B allografts were significantly reduced versus that shown with treatment with the CXC chemokine receptor type 4 antagonist in group C.

CONCLUSIONS

Together, these data strongly implicate that CXC chemokine receptor type 4 antagonism alleviated renal interstitial fibrosis in long-term surviving allografts by down-regulating expression of transforming growth factor β1.

Determining the amount of training needed for competency of anesthesia trainees in ultrasonographic identification of the cricothyroid membrane

Background

Airway guidelines recommend the use of ultrasound to localize the cricothyroid membrane prior to airway manipulation in difficult airways. In this study, we aimed to determine the amount of training anesthesia trainees would need to achieve competence in bedside ultrasound to identify the cricothyroid membrane.

Methods

This is a prospective non-randomized cohort study in the Department of Anesthesia at Mount Sinai Hospital (Toronto, Ontario, Canada). Following institutional ethics approval, six anesthesia trainees consisting of four residents and two fellows underwent a 2-h training session on neck ultrasound to identify neck landmarks and the cricothyroid membrane. The trainees had no previous airway ultrasound experience. One-two weeks later, each trainee performed consecutive neck ultrasound scans on 20 healthy volunteers to identify the cricothyroid membrane. Cumulative sum (CUSUM) learning curves were constructed for each trainee. Primary outcome was the number of ultrasound examinations required to achieve competence, defined as 90% success rate in a series of 20 ultrasound scans. Secondary outcomes were the overall success rate, the time (sec.) required to perform the task, and 3-month skills assessment.

Results

CUSUM analysis showed four trainees achieved competence with a mean [range] success rate of 94.0% [90–100%] and a median [range] number of attempts of 14 [9–18]. Two trainees did not achieve competence, but obtained a success rate of 75.0 and 80.0% each. Overall (number of attempts) success rate was 88.3% (106/120) with a mean (SD) time of 36.9 (9.0) sec. Three months after training, ultrasound of five consecutive neck scans showed a mean success rate of 86.7% (26/30) and mean (SD) time of 47.7 (16.0) sec.

Conclusions

After a short 2-h training session, most anesthesia trainees (n = 4/6) achieved competence in ultrasound-identification of the cricothyroid membrane with less than 20 scans in a mean time less than 60 s., and that they remain reasonably competent 3 months later. The learning curve for ultrasound identification of the cricothyroid membrane seems to be short even without prior airway ultrasound experience.

Neck circumference to inter-incisor gap ratio: a new predictor of difficult laryngoscopy in cervical spondylosis patients

Background

Preoperative airway assessment help anticipate a difficult airway. We hypothesized that a close association existed between difficult laryngoscopy and the neck circumference/inter-incisor gap ratio (RNIIG). Our aim was to determine its utility in predicting difficult laryngoscopy in cervical spondylosis patients.

Methods

Two hundred thirteen consecutive patients, aged 20–70 years, scheduled to undergo cervical spine surgery under general anesthesia, were recruited. Preoperative assessments included inter-incisor gap (IIG), thyromental distance (TMD), neck circumference (NC), NC/IIG ratio (RNIIG), NC/TMD ratio (RNTMD) and modified Mallampati test (MMT). Cormack–Lehane scales were assessed during intubation. The anesthesiologist was blinded to the airway assessments. RNIIG’s ability to predict difficult laryngoscopy was compared with that of established predictors.

Results

Difficult laryngoscopy incidence was 16.4%. Univariate analysis showed that male gender, increased age, weight, NC, RNIIG and RNTMD, decreased IIG and TMD, and MMT 3 and 4 were associated with difficult laryngoscopy. Binary multivariate logistic regression analyses identified only one factor that was independently associated with difficult laryngoscopy: RNIIG. The odds ratio and 95% confidence interval (95% CI) were 1.932 (1.504–2.482). RNIIG (≥9.5) exhibited the largest area under the curve (0.80; 95% CI 0.73–0.86) and the highest sensitivity (88.6%; 95% CI 78.1–99.1) and negative predictive value (96.6%; 95% CI 94.0–99.2), confirming its better predictive ability.

Conclusions

RNIIG is a new and simple predictor with a higher level of efficacy, and could help anesthetists plan for difficult laryngoscopy management in cervical spondylosis patients.

Trial registration

ChiCTR-OON-16008320 (April 19th, 2016).

Effect of nasal oxygen supplementation during apnoea of intubation on arterial oxygen levels: A prospective randomised controlled trial

Background and Aims:

Apnoeic oxygenation during laryngoscopy has been emphasised in recent recommendations for airway management. We aimed to compare the effect of nasal oxygen supplementation on time for pulse oximeter oxygen saturation (SpO₂) to fall from 100% to 92% (desaturation safety time), to assess the arterial oxygen partial pressures (PaO₂) with and without nasal oxygen supplementation and the time for SpO₂ to recover from 92% to 100% after initiation of ventilation.

Methods:

This is a prospective randomised placebo-controlled trial involving sixty patients, where nasal oxygen supplementation given at 10 L/min during apnoea of laryngoscopy in one group of patients (Group O₂) was compared to no oxygen supplementation in other group (Group NoO₂). Desaturation safety period and the PaO₂ just after intubation were compared. Time for SpO₂ to increase to 100% after initiation of ventilation was also assessed. Demographic details were compared using the Chi-square and t-tests. Student's t-test for independent variables was used to compare means of data obtained.

Results:

Desaturation safety period at 415.46 ± 97.23 seconds in group O₂ versus 378.69 ± 89.31 seconds in group NoO₂(P = 0.213) and PaO₂(P = 0.952) and time to recovery of SpO2 (P = 0.058) were similar in both groups. Rise in arterial carbon dioxide secondary to apnoea was slower in oxygen supplementation group (P = 0.032).

Conclusion:

Apnoeic oxygen supplementation at 10 L/min flow by nasal prong did not significantly prolong the apnoea desaturation safety periods or the PaO₂ in our study.

All India Difficult Airway Association 2016 guidelines for the management of unanticipated difficult tracheal intubation in adults

The All India Difficult Airway Association (AIDAA) guidelines for management of the unanticipated difficult airway in adults provide a structured, stepwise approach to manage unanticipated difficulty during tracheal intubation in adults. They have been developed based on the available evidence; wherever robust evidence was lacking, or to suit the needs and situation in India, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the AIDAA and the Indian Society of Anaesthesiologists. We recommend optimum pre-oxygenation and nasal insufflation of 15 L/min oxygen during apnoea in all patients, and calling for help if the initial attempt at intubation is unsuccessful. Transnasal humidified rapid insufflations of oxygen at 70 L/min (transnasal humidified rapid insufflation ventilatory exchange) should be used when available. We recommend no more than three attempts at tracheal intubation and two attempts at supraglottic airway device (SAD) insertion if intubation fails, provided oxygen saturation remains ≥ 95%. Intubation should be confirmed by capnography. Blind tracheal intubation through the SAD is not recommended. If SAD insertion fails, one final attempt at mask ventilation should be tried after ensuring neuromuscular blockade using the optimal technique for mask ventilation. Failure to intubate the trachea as well as an inability to ventilate the lungs by face mask and SAD constitutes 'complete ventilation failure', and emergency cricothyroidotomy should be performed. Patient counselling, documentation and standard reporting of the airway difficulty using a 'difficult airway alert form' must be done. In addition, the AIDAA provides suggestions for the contents of a difficult airway cart.

Emergency Surgical Airways Following Activation of a Difficult Airway Management Team in Hospitalized Critically Ill Patients: A Case Series

INTRODUCTION

An emergency surgical airway (ESA) is widely recommended for securing the airway in critically ill patients who cannot be intubated or ventilated. Little is known of the frequency, clinical circumstances, management methods, and outcomes of hospitalized critically ill patients in whom ESA is performed outside the emergency department or operating room environments.

METHODS

We retrospectively reviewed all adult patients undergoing ESA in our intensive care units (ICUs) and other hospital units from 2008 to 2012 following activation of our difficult airway management team (DAMT).

RESULTS

Of 207 DAMT activations for native airway events, 22 (10.6%) events culminated in an ESA, with 59% of these events occurring in ICUs with the remainder outside the ICU in the context of rapid response team activations. Of patients undergoing ESA, 77% were male, 63% were obese, and 41% had a history of a difficult airway (DA). Failed planned or unplanned extubations preceded 61% of all ESA events in the ICUs, while bleeding from the upper or lower respiratory tract led to ESA in 44% of events occurring outside the ICU. Emergency surgical airway was the primary method of airway control in 3 (14%) patients, with the remainder of ESAs performed following failed attempts to intubate. Complications occurred in 68% of all ESAs and included bleeding (50%), multiple cannulation attempts (36%), and cardiopulmonary arrest (27%). Overall hospital mortality for patients undergoing ESA was 59%, with 38% of deaths occurring at the time of the airway event.

CONCLUSION

An ESA is required in approximately 10% of DA events in critically ill patients and is associated with high morbidity and mortality. Efforts directed at early identification of patients with a difficult or challenging airway combined with a multidisciplinary team approach to management may reduce the overall frequency of ESA and associated complications.

Bronchoscopic concerns in Proteus syndrome: a case report

Proteus syndrome (PS) is a rare congenital hamartomatous disorder with multisystem involvement. PS shows highly clinical variability due to overgrowth of the affected areas, and several features can make anesthetic management challenging. Little is known about the airway problem associated with anesthesia in PS patients. An 11-year-old girl with PS was scheduled for ear surgery under general anesthesia. She had features complicating intubation including facial asymmetry and disproportion, abnormal teeth, limitation of neck movement due to torticollis, and thoracolumbar scoliosis. This study reports on a case of deformed airway of a PS patient under fiberoptic bronchoscopy.

Fiberoptic nasopharyngoscopy for evaluating a potentially difficult airway in a patient with elevated intracranial pressure

A 62-year-old man with a left temporal lobe tumor was scheduled for a semiurgent craniotomy for tumor excision. Previously, the patient had a laryngeal carcinoma that was resected and treated with chemotherapy and radiotherapy and a history of laryngeal biopsy with awake fiberoptic intubation. Because a difficult airway was anticipated, awake fiberoptic nasopharyngoscopy of the airway was performed under topical anesthesia in the operating room. This revealed a narrow glottic opening with no supraglottic pathology or friable tissue. Based on these airway observations, we proceeded safely with intravenous induction and secured the airway in a controlled fashion, thereby minimizing the risk of increased intracranial pressure and catastrophic complications. Nasopharyngoscopy can be used safely to evaluate the upper airway to stratify airway management in patients with a history of head and neck cancer presenting for neurosurgical procedures in the setting of elevated intracranial pressure.

Two lost airways and one unexpected problem: undiagnosed tracheal stenosis in a morbidly obese patient

Anesthetic care of the morbidly obese is complex due to anatomic and physiologic alterations. Airway management in particular can be challenging. High body mass index is predictive of difficult ventilation and possibly difficult intubation. Other airway anomalies, such as tracheal stenosis, add to the complexity of airway management. Tracheal stenosis, a form of central airway obstruction, may be challenging to diagnose, especially in the obese. Comorbidities can mask the diagnosis and routine imaging may fail to identify the pathology. We present the case of a morbidly obese patient with 2 failed intubations due to difficult anatomy compounded with undiagnosed tracheal stenosis.

Device and Medication Preferences of Canadian Physicians for Emergent Endotracheal Intubation in Critically Ill Patients

OBJECTIVES

Various medications and devices are available for facilitation of emergent endotracheal intubations (EETIs). The objective of this study was to survey which medications and devices are being utilized for intubation by Canadian physicians.

METHODS

A clinical scenario-based survey was developed to determine which medications physicians would administer to facilitate EETI, their first choice of intubation device, and backup strategy should their first choice fail. The survey was distributed to Canadian emergency medicine (EM) and intensive care unit (ICU) physicians using web-based and postal methods. Physicians were asked questions based on three scenarios (trauma; pneumonia; heart failure) and responded using a 5-point scale ranging from "always" to "never" to capture usual practice.

RESULTS

The survey response rate was 50.2% (882/1,758). Most physicians indicated a Macintosh blade with direct laryngoscopy would "always/often" be their first choice of intubation device in the three scenarios (mean 85% [79%-89%]) followed by video laryngoscopy (mean 37% [30%-49%]). The most common backup device chosen was an extraglottic device (mean 59% [56%-60%]). The medications most physicians would "always/often" administer were fentanyl (mean 45% [42%-51%]) and etomidate (mean 38% [25%-50%]). EM physicians were more likely than ICU physicians to paralyze patients for EETI (adjusted odds ratio 3.40; 95% CI 2.90-4.00).

CONCLUSIONS

Most EM and ICU physicians utilize direct laryngoscopy with a Macintosh blade as a primary device for EETI and an extraglottic device as a backup strategy. This survey highlights variation in Canadian practice patterns for some aspects of intubation in critically ill patients.

A deliberately restricted laryngeal view with the GlideScope® video laryngoscope is associated with faster and easier tracheal intubation when compared with a full glottic view: a randomized clinical trial

INTRODUCTION

During video laryngoscopy (VL) with angulated or hyper-curved blades, it is sometimes difficult to complete tracheal intubation despite a full view of the larynx. When using indirect VL, it has been suggested that it may be preferable to obtain a deliberately restricted view of the larynx to facilitate passage of the endotracheal tube. We used the GlideScope® GVL video laryngoscope (GVL) to test whether deliberately obtaining a restricted view would result in faster and easier tracheal intubation than with a full view of the larynx.

METHODS

We recruited 163 elective surgical patients and randomly allocated the participants to one of two groups: Group F, where a full view of the larynx was obtained and held during GVL-facilitated tracheal intubation, and Group R, with a restricted view of the larynx (< 50% of glottic opening visible). Study investigators experienced in indirect VL performed the intubations. The intubations were recorded and the video recordings were subsequently assessed for total time to intubation, ease of intubation using a visual analogue scale (VAS; where 0 = easy and 100 = difficult), first-attempt success rate, and oxygen saturation after intubation. Complications were also assessed.

RESULTS

The median [interquartile range (IQR)] time to intubation was faster in Group R than in Group F (27 [22-36] sec vs 36 [27-48] sec, respectively; median difference, 9 sec; 95% confidence interval [CI], 5 to 13; P < 0.001). The median [IQR] VAS rating for ease of intubation was also better in Group R than in Group F (14 [6-42) mm vs 50 mm [17-65], respectively; median difference, 20 mm; 95% CI, 10 to 31; P < 0.001). There was no difference between groups regarding the first-attempt success rate, oxygen saturation immediately after intubation, or complications.

CONCLUSIONS

Using the GVL with a deliberately restricted view of the larynx resulted in faster and easier tracheal intubation than with a full view and with no additional complications. Our study suggests that obtaining a full or Cormack-Lehane grade 1 view may not be desirable when using the GVL. This trial was registered at ClinicalTrials.gov: NCT02144207.

Effect of head position on the success rate of blind intubation using intubating supraglottic airway devices

BACKGROUND

To evaluate the effect of head position on the performance of intubating supraglottic airway devices, we compared the success rate of blind intubation in the head-elevated and the pillowless head positions with the LMA Fastrach and the air-Q, and the change of glottic visualization through the air-Q.

METHODS

We assigned 193 patients to two groups according to the device used and subgrouped by head position used for intubation: Fastrach/pillowless, Fastrach/head-elevated, air-Q/pillowless, and air-Q/head-elevated. Blind intubation through the Fastrach or the air-Q was attempted up to twice after induction of general anesthesia. Before the attempt at blind intubation with the air-Q, the percentage of glottic opening (POGO) score was also fiberscopically evaluated at the outlet of the device in both head positions in a cross-over fashion.

RESULTS

The Fastrach significantly facilitated blind intubation compared with the air-Q in both the pillowless and head-elevated positions: 87.2% in Fastrach/pillowless vs 65.9% in air-Q/pillowless (P=.048), 90% in Fastrach/head-elevated vs 53.7% in air-Q/head-elevated (P<.001). The head-elevated position did not significantly affect the success rate of blind intubation for either device (P=.97 in Fastrach, P=.37 in air-Q). Although the head-elevated position significantly improved the POGO score from the median (10-90 percentile) 60% (0-100%) in the pillowless position to 80% (0-100%) (P=.008), it did not contribute to successful blind intubation with the air-Q.

CONCLUSION

Although the head-elevated position improved glottic visualization in the air-Q, the head position had minimal influence on the success rate of blind intubation with either the Fastrach or the air-Q.

Tracheal extubation in children with difficult airways: a descriptive cohort analysis

BACKGROUND

Tracheal extubation in children with difficult airways may be associated with an increased risk of perioperative adverse events.

AIMS

The aim of this study was to describe the exubation techniques used/ success rates/ adverse events related to tracheal extubation practices in children with difficult airways.

METHODS

A retrospective analysis of tracheal extubation practices in the difficult airway population over a 78-month period was performed. Difficult airway was defined as a Cormack and Lehane Grade 3 view or greater, and/or tracheal intubation requiring ≥ 3 attempts, and/or the need for an alternate device to direct laryngoscopy for successful tracheal intubation, and/or difficult mask ventilation. Reasons for difficult airway, demographic/surgical data, technique(s) for tracheal extubation, success/failure of tracheal extubation, and adverse events were recorded. A failed tracheal extubation was defined as any adverse event related to the airway occurring within 6 h of extubation requiring reintubation.

RESULTS

A total of 519 patients were reported to have a difficult airway during this study period in a tertiary care pediatric center. Of these, 137 patients (26%) met inclusion criteria. Tracheal extubation was successfully performed in 130 patients (95%). The majority of tracheal exubations were performed without the use of additional airway adjuncts straight onto anesthesia face mask (121/137; 88%). Extubation failure occurred in seven cases (5%). Among the failed extubations, 6/7 children (85%) had evidence of severe upper airway obstruction and were <10 kg in weight. Of these children, one child required emergency tracheostomy, and two children (one with tracheal stenosis and other with spinal muscular atrophy) suffered from hypoxemic cardiac arrest and anoxic brain damage, respectively, and eventually died.

CONCLUSIONS

In the studied population of children with difficult airways handled in a tertiary center environment, the majority of tracheal extubations could be performed without the use of airway adjuncts. In a minority of patients, tracheal extubation was associated with severe adverse outcomes.

Improving Pediatric Emergency Care by Implementing an Eligible Learner Endotracheal Intubation Policy

OBJECTIVES

Although endotracheal intubations (ETIs) are high-risk, low-frequency events, there are no nationally accepted training pathways or measures to ensure ETI competence for emergency department (ED) providers. Our objective was to determine whether implementation of an eligible learner ETI policy (ELETIP) led to improved first ETI attempt success rates and decreased immediate airway-related complications.

METHODS

This was a retrospective cross-sectional before-and-after study of outcomes after ELETIP implementation. The primary outcome was proportion of successful first ETI attempts; secondary outcomes were number of intubation attempts, time to intubation, need to call anesthesia for intubation, and airway-related complications.

RESULTS

Three hundred ninety patients were included (median age, 1.3 y; range, 1 day-24.7 y): 219 (56%) and 171 (44%) in the pre- and post-ELETIP periods, respectively. First successful ETI attempts increased from 65.1% to 75.7% (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.07-2.62). Secondary outcomes included mean number of intubation attempts (1.6-1.4, P = 0.01), time to intubation (5.6-4.9 minutes, P = 0.07), anesthesia intubations in the ED (5.9%-2.9%; OR, 0.48; 95% CI, 0.17-1.37), and intubation-related complications (32%-25.7%; OR, 0.74; 95% CI, 0.47-1.15).

CONCLUSIONS

An ELETIP is effective in improving ED care by increasing first ETI attempt success rates while decreasing overall intubation attempts. Physicians and physician learners with anesthesia training for critical airway management training have high ETI attempt success rates. Airway management training is essential to physician education and airway management skills for improving outcomes.

Comparison of the GlideRite to the conventional malleable stylet for endotracheal intubation by the Macintosh laryngoscope: a simulation study using manikins

Objective

To compare the effectiveness of the GlideRite stylet with the conventional malleable stylet (CMS) in endotracheal intubation (ETI) by the Macintosh laryngoscope.

Methods

This study is a randomized, crossover, simulation study. Participants performed ETI using both the GlideRite stylet and the CMS in a normal airway model and a tongue edema model (simulated difficult airway resulting in lower percentage of glottic opening [POGO]).

Results

In both the normal and tongue edema models, all 36 participants successfully performed ETI with the two stylets on the first attempt. In the normal airway model, there was no difference in time required for ETI (T_ETI) or in ease of handling between the two stylets. In the tongue edema model, the T_ETI using the CMS increased as the POGO score decreased (POGO score was negatively correlated with T_ETI for the CMS, Spearman’s rho=-0.518, P=0.001); this difference was not seen with the GlideRite (rho=-0.208, P=0.224). The T_ETI was shorter with the GlideRite than with the CMS, however, this difference was not statistically significant (15.1 vs. 18.8 seconds, P=0.385). Ease of handling was superior with the GlideRite compared with the CMS (P=0.006).

Conclusion

Performance of the GlideRite and the CMS were not different in the normal airway model. However, in the simulated difficult airway model with a low POGO score, the GlideRite performed better than the CMS for direct laryngoscopic intubation.

Evaluation of six different airway devices regarding regurgitation and pulmonary aspiration during cardio-pulmonary resuscitation (CPR) - A human cadaver pilot study

BACKGROUND

Chest compressions and ventilation are lifesaving tasks during cardio-pulmonary resuscitation (CPR). Besides oxygenation, endotracheal intubation (ETI) during CPR is performed to avoid aspiration of gastric contents. If intubation is difficult or impossible, supraglottic airway devices are utilized. We tested six different airway devices regarding their potential to protect against regurgitation and aspiration during CPR in a randomized experimental human cadaver study.

METHODS

Five-hundred ml of 0.01% methylene-blue-solution were instilled into the stomach of 30 adult human cadavers via an oro-gastric tube. The cadavers were then randomly assigned to one of six groups, resulting in 5 cadavers in each group. Airway management was performed with either bag-valve ventilation, Laryngeal Tube, EasyTube, Laryngeal Mask (Classic), I-Gel, or ETI. Thereafter 5min of CPR were performed according to the 2010 Guidelines of the European Resuscitation Council. Pulmonary aspiration was defined as the presence of methylene-blue-solution below the vocal cords or the ETI cuff as assessed by fiber-optic bronchoscopy.

RESULTS

Thirty cadavers were included (14 females, 16 males). Aspiration was detected in three out of five cadavers receiving bag-valve ventilation and in two out of five intubated with LMA or I-Gel. In cadavers intubated with the LT, aspiration occurred in one out of five cases. No aspiration could be detected in cadavers intubated with ETI and EasyTube.

CONCLUSION

This study provides experimental evidence that, during CPR, ETI offers superior protection against regurgitation and pulmonary aspiration of gastric contents than supraglottic airway devices or bag-valve ventilation.

Assessment before airway management

It is wise to plan and prepare for the unexpected difficult airway. Although it is essential to take a history and examine every patient prior to airway management, preoperative anticipation of a difficult airway occurs in only 50% of patients subsequently found to have a difficult airway. Bedside screening tests lack accuracy. The modified Mallampati test and the measurement of thyromental distance are unreliable for prediction of difficult tracheal intubation. Knowledge of risk factors for various airway management techniques may help when devising an airway management plan.