The normal and the challenging pediatric airway

Management of a child’s airway is one of the main sources of stress for anesthetists who do not routinely anesthetize children. Unfortunately, trainees are gaining less experience in pediatric airway management than in the past, which is particularly difficult at a time when some beliefs about airway management are being challenged and airway management is less standardized. Fortunately, most children have an easily managed, normal airway. Nevertheless, it is of vital importance to teach our trainees the basic airway skills that are probably the most important skill in an anesthetists’ repertoire when it comes to a difficult airway situation. This review focuses on the airway management in children with a normal and a challenging airway. Different choices of airway management in children, and their advantages and disadvantages are discussed. Furthermore, the three broad causes of a challenging airway in children and infants are highlighted – the difficulty obtaining a mask seal, difficulty visualizing the vocal cords, and the third cause in which the larynx can be visualized but the difficulty lies at or beyond that level. Guidelines are given how to deal with these patients as well as with the feared but rare scenario of ‘cannot ventilate, cannot intubate’ in children.     

Evaluation of the airway of the SimMan full-scale patient simulator

BACKGROUND: SimMan is a full-scale patient simulator, capable of simulating normal and pathological airways. The performance of SimMan has never been critically evaluated. METHODS: Sixty subjects (anesthesiologists, nurse anesthetists, and anesthesia residents) performed mask ventilation, laryngeal mask insertion and endotracheal intubation on SimMan. The simulator's airway was evaluated using visual analog scales (VAS) and by measuring the subject's performances. RESULTS: The SimMan full-scale patient simulator's airway is generally acceptably realistic but it significantly differs from the human airway in important aspects. Mask seal was more difficult than in humans whereas Laryngeal mask (LMA) insertion and function was acceptable. The distance from the teeth to the vallecula was too short. Cervical spine mobility was significantly reduced in the 'reduced neck movement' mode but the intubation was only slightly more difficult than in the 'normal' mode. CONCLUSION: The SimMan full-scale patient simulator's airway is generally acceptably realistic but it significantly differs from the human airway in important aspects. The user must be aware of these aspects in order to obtain maximum benefit from training and evaluation scenarios and when using the simulator for testing new equipment and techniques.     

An institutional approach to the management of the ‘Can't Intubate,Can't Oxygenate’ emergency in children

The ‘Can't Intubate Can't Oxygenate’ emergency is rare in children. Nevertheless, airway clinicians involved in pediatric airway management must be able to rescue the airway percutaneously through the front of the neck should this situation be encountered. Little evidence exists in children to guide rescue techniques, and extrapolation of adult evidence may be problematic due to anatomical differences. This document reviews the currently available evidence, and presents a practical approach to standardizing equipment, techniques, and training for managing the ‘Can't Intubate Can't Oxygenate’ emergency in children.     

Management of the difficult and failed airway in obstetric anesthesia

Difficulty with airway management in obstetric patients occurs infrequently and failure to secure an airway is rare. A failed airway may result in severe physical and emotional morbidity and possibly death to the mother and baby. Additionally, the family, along with the medical and nursing staff, may face emotional and financial trauma. With the increase in the number of cesarean sections performed under regional anesthesia, the experience and training in performing endotracheal intubations in obstetric anesthesia has decreased. This article reviews the management of the difficult and failed airway in obstetric anesthesia. Underpinning this important topic is the difference between the nonpregnant and pregnant state. Obstetric anatomy and physiology, endotracheal intubation in the obstetric patient, and modifications to the difficult airway algorithms required for obstetric patients will be discussed. We emphasize that decisions regarding airway management must consider the urgency of delivery of the baby. Finally, the need for specific equipment in the obstetric difficult and failed airway is discussed. Worldwide maternal mortality reflects the health of a nation. However, one could also claim that, particularly in Western countries, maternal mortality may reflect the health of the specialty of anesthesia.     

The design of the perfect pediatric supraglottic airway device

The design evolution of the pediatric supraglottic airway device has experienced a long and productive journey. We have a wealth of clinical studies to support progress and advancements in pediatric clinical practice. While all of the  supraglottic airway devices have been used successfully in millions of children, it is important to be aware of design advantages and disadvantages of the different models of  supraglottic airway devices. Current pediatric supraglottic airway devices may be improved in design to be more ideal. Industry‐changing technological advancements are likely to occur in the near future, which may further improve clinical performance of these devices.     

Incidence and predictors of difficult laryngoscopy in 11.219 pediatric anesthesia procedures

Objective: Difficult laryngoscopy in pediatric patients undergoing anesthesia. Aim: This retrospective analysis was conducted to investigate incidence and predictors of difficult laryngoscopy in a large cohort of pediatric patients receiving general anesthesia with endotracheal intubation. Background: Young age and craniofacial dysmorphy are predictors for the difficult pediatric airway and difficult laryngoscopy. For difficult laryngoscopy, other general predictors are not yet described. Methods: Retrospectively, from a 5‐year period, data from 11.219 general anesthesia procedures in pediatric patients with endotracheal intubation using age‐adapted Macintosh blades in a single center (university hospital) were analyzed statistically. Results: The overall incidence of difficult laryngoscopy [Cormack and Lehane (CML) grade III and IV] was 1.35%. In patients younger than 1 year, the incidence of CML III or IV was significantly higher than in the older patients (4.7% vs 0.7%). ASA Physical Status III and IV, a higher Mallampati Score (III and IV) and a low BMI were all associated (P < 0.05) with difficult laryngoscopy. Patients undergoing oromaxillofacial surgery and cardiac surgery showed a significantly higher rate of CML III/IV findings. Conclusion: The general incidence of difficult laryngoscopy in pediatric anesthesia is lower than in adults. Our results show that the risk of difficult laryngoscopy is much higher in patients below 1 year of age, in underweight patients and in ASA III and IV patients. The underlying disease might also contribute to the risk. If the Mallampati score could be obtained, prediction of difficult laryngoscopy seems to be reliable. Our data support the existing recommendations for a specialized anesthesiological team to provide safe anesthesia for infants and neonates.     

A cohort evaluation of the Laryngeal Mask Airway‐Supreme™ in children

Objectives: To assess the clinical performance of the laryngeal mask airway‐Supreme in children. Aim: The purpose of this prospective audit was to evaluate the feasibility of the laryngeal mask airway‐Supreme in clinical practice and generate data for future comparison trials. Background: The laryngeal mask airway‐Supreme is a new second‐generation supraglottic airway that was recently released in limited pediatric sizes (sizes 1, 2). Methods: One hundred children, ASA I‐III, newborn to 16 years of age, and undergoing various procedures requiring a size 1, 2, or 3 laryngeal mask airway‐Supreme were studied. Assessments included insertion success rates, airway leak pressures, success of gastric tube insertion, quality of airway, and perioperative complications. Results: The first‐time insertion success rate was 97%, with an overall insertion success rate of 100%. The mean initial airway leak pressure for all patients was 22.3 ± 6.6 cm H₂O. Gastric tube placement was possible in 98% of patients. Complications were noted in six patients: coughing or laryngospasm (n = 3), sore throat (n = 1), and dysphonia (n = 2). Conclusions: The laryngeal mask airway‐Supreme was inserted with a high degree of success on the first attempt by clinicians with limited prior experience with the device. It was effectively used for a variety of procedures in children undergoing spontaneous and mechanical ventilation with minimal complications. The leak pressures demonstrated in this study, along with access for gastric decompression, suggest that the laryngeal mask airway‐Supreme may be an effective device for positive pressure ventilation in children.     

Strategies for the prevention of airway complications – a narrative review

Despite being infrequent, complications of airway management remain an important contributor to morbidity and mortality during anaesthesia and care of the critically ill. Developments in the last three decades have made anaesthesia safer, and this has been mirrored in the equipment and techniques available for airway management. Modern technology including novel oxygenation modalities, widespread availability of capnography, second‐generation supraglottic airway devices and videolaryngoscopy provide the tools to make airway management safer still. However, technology will only take safety so far, and non‐technical aspects of airway management are critically important for communication and decision making during airway crises, acknowledging a ‘cannot intubate, cannot oxygenate’ situation and transitioning to emergency front of neck airway. Randomised controlled trials provide little useful information about safety in this setting, and data from registries and databases are likely to be of more value. This narrative review focuses on recent evidence in this area.     

38例老年病人人工气道意外原因分析及护理对策

目的 提高对人工气道意外的预见性护理及紧急处理能力。方法 回顾性分析38例老年病人人工气道发生意外的情况及其原因。结果 意外情况有导管扭曲，堵塞，脱出，气囊破裂，出血等；主要原因为固定不良，外力牵拉，湿化不良，排痰不畅。机械损伤等。结论 防止人工气道意外，必须加强预见性护理，如加强导管的固定和保护，加强气道湿化与排痰；做好气囊管理，避免机械损伤等。同时掌握应急处理措施，以确保护理安全。     

A rather unconventional use of the laryngeal mask airway

Jaw masses are often associated with difficult airway and very often anesthesiologists have to use ingenious but safe techniques to secure the airway. This report is upon awake insertion of the laryngeal mask airway in a patient with a huge jaw tumor.     

Identification of the difficult airway

Failure to identify a difficult airway can have serious consequences. It is essential that a thorough assessment of a patient's airway is made prior to anaesthesia, including taking a history, performing a focused examination, and reviewing any relevant investigations. The predictive power of individual bedside airway assessments is limited, though the use of composite scores may increase accuracy. Where predictors of potential difficulty are identified, these must be taken into account when formulating an appropriate airway management strategy and executing it. Despite thorough preoperative evaluation and planning, situations still arise where an unexpected difficult airway is encountered, where maintenance of adequate oxygenation must take precedence.     

Difficult airway management in the neonate: a simple method of intubating through a laryngeal mask airway

Tracheal intubation through a laryngeal mask airway is one option for securing an airway in the patient with a difficult airway. A variety of techniques and equipment have been used to stabilize the position of the tracheal tube while removing the laryngeal mask airway. We have shown that if a fibreoptic bronchoscope is used to place an tracheal tube through a laryngeal mask in neonates, additional equipment is not needed to remove the laryngeal mask airway without endangering tracheal tube placement. This is possible even in small neonates.     

An assessment of the tolerability of the Cook staged extubation wire in patients with known or suspected difficult airways extubated in intensive care

The Cook staged extubation set (Cook Medical) has been developed to facilitate management of the difficult airway. A guidewire inserted before tracheal extubation provides access to the subglottic airway should re‐intubation be required. This prospective cohort study examines patients’ tolerance of the guidewire and its impact on clinical status around tracheal extubation in the intensive care unit. Vital signs, incidence of symptoms and patient tolerance of the wire were recorded. Twenty‐three patients were enrolled and 17 (73%) tolerated the wire for 4 h. Nasendoscopy was performed in 11 of these patients and revealed one wire was in the oesophagus. The most common symptom was a mild intermittent cough in 13 patients. There was no impact of the guidewire on nursing care in 16 patients, tolerable impact in five and severe impact necessitating removal of the wire in one patient.     

Description and function of a difficult airway service

The goal of the Pediatric Difficult Airway Service (DAS) is to improve the care of children with airway abnormalities primarily through identification of children at risk for failed airway management. The airway service encourages early recognition and provides consultation, a plan for airway management, expertise in airway management, and follow‐up care for children who have a difficult airway. The service has improved the education of healthcare professionals and heightened awareness about the consequences of failed airway management.     

Airway management in spontaneously breathing anaesthetized children: comparison of the Laryngeal Mask Airway with the cuffed oropharyngeal airway

BACKGROUND: The efficacy and safety of the smallest size of the cuffed oropharyngeal airway (COPA) for school age, spontaneously breathing children was investigated and compared with the Laryngeal Mask Airway (LMA). METHODS: Seventy children of school age (7-16 years) were divided into two groups: the COPA (n=35) and the LMA (n=35). Induction was with propofol i.v. or halothane, nitrous oxide, oxygen and fentanyl. After depression of laryngopharyngeal reflexes, a COPA size 8 cm or an LMA was inserted. Ventilation was manually assisted until spontaneous breathing was established. For maintenance, propofol i.v. and fentanyl or halothane with nitrous oxide were used. Local anaesthesia or peripheral blocks were also used. RESULTS: Both extratracheal airways had a highly successful insertion rate, but more positional manoeuvres to achieve a satisfactory airway were required with the COPA, 28.6% versus LMA 2.9%. The need to change the method of airway management was higher (8.6%) in the COPA group. After induction, the need for assisted ventilation was higher in the LMA group 54.3% versus 20% in the COPA group. Airway reaction to cuff inflation was higher in the LMA group 14.3% versus COPA 5.7%. Problems during surgery were similar, except continuous chin support to establish an effective airway was more frequent (11.4%) in the COPA group. In the postoperative period, blood on the device and incidence of sore throat were detected less in the COPA group. CONCLUSIONS: The COPA is a good extratracheal airway that provides new possibilities for airway management in school age children with an adequate and well sealed airway, during spontaneous breathing or during short-term assisted manual ventilation.     

Prospective evaluation of the self-pressurized air-Q intubating laryngeal airway in children

Objectives: To assess the clinical efficacy of the self‐pressurized air‐Q ILA? (ILA‐SP). Aim: The purpose of this prospective audit was to evaluate the feasibility of the ILA‐SP in clinical practice and generate data for future comparison trials. Background: The ILA‐SP is a new first‐generation supraglottic airway for children with a self‐adjusting cuff and lack of a pilot balloon. Methods: Over a 4‐month period, 352 children with an ASA physical status of I–III, newborn to 18 years of age, undergoing various procedures were studied. Data points assessed included insertion success rates, airway leak pressures, quality of ventilation, and perioperative complications associated with the use of this device. Results: In 349 of the 352 patients in this study, the ILA‐SP was used successfully as a primary supraglottic airway device in a variety of patients. Three patients required conversion to a standard laryngeal mask airway or a tracheal tube. The mean initial airway leak pressure for all patients was 17.8 ± 5.4 cm H₂O, and 20.4 ± 5.5 cm H₂O when re‐checked at 10 min, which was statistically significant (P < 0.001). Complications were limited to 14 patients and related to reflex activation of the airway (coughing, laryngospasm, and bronchospasm) (n = 10), sore throat (n = 3), and blood staining on removal of the device (n = 1). There were no episodes of regurgitation, aspiration, or hoarseness. Conclusions: Acceptable clinical performance was demonstrated with the ILA‐SP for a variety of procedures in infants and children with spontaneous and positive pressure ventilation. Future studies comparing this device to other supraglottic airways may provide useful information regarding the safety of the ILA‐SP in pediatric clinical practice.     

Anesthesia for shared airway surgery in children

Shared airway surgery in children is a complex, high‐risk undertaking that requires continuous communication and cooperation between the anesthetic and surgical teams. Airway abnormalities commonly seen in children, the surgical options, and the anesthetic techniques that can be used to care for this vulnerable population are discussed. Many of these procedures were traditionally carried out using jet ventilation, or intermittent tracheal intubation, but increasingly spontaneously breathing “tubeless” techniques are being used. This review has been written from both the surgical and anesthetic perspective, highlighting the concerns that both specialties have in relation to the maintenance of surgical access and operating conditions, and the need for the provision of anesthesia, oxygenation, and ventilation where the airway is the primary site of operation.