Use of a gum elastic bougie for tracheal intubation with Pentax-AWS airway scope

Pentax-AWS laryngoscope (Pentax, Tokyo, Japan) consists of a disposable anatomically shaped blade, a 12-cm cable with a charge-coupled device (CCD) camera and a 2.4-inch liquid crystal device (LCD) color monitor display. A tracheal tube can be attached to the right side of the blade. The device may be useful in patients with difficult airways. One limitation of the device is that intubation may be difficult if it is difficult to position the glottis to the target symbol on the monitor display. We experienced such a difficulty in four patients, and the use of a gum elastic bougie enabled intubation. In a 57-year-old woman with a difficult airway, tracheal intubation using either a Macintosh laryngoscope or a fiberscope had failed. By inserting the AWS laryngoscope, the glottis was easily seen on the monitor display. Nevertheless, it was difficult to position the glottis to the target symbol, and advancing a tracheal tube collided with the tissue around the glottis. A bougie was passed through the tracheal tube, and it became possible to insert the bougie into the trachea by adjusting the angle of its tip. The tracheal tube was then easily passed over the bougie into the trachea. We successfully used the same technique in other three patients. We believe that the gum elastic bougie can be useful for tracheal intubation using the Pentax-AWS laryngoscope.     

Intubação traqueal difícil com fibra óptica em bebê de um mês de idade com síndrome de Treacher Collins

Neonates and small infants with craniofacial malformation may be very difficult or impossible to mask ventilate or intubate. We would like to report the fiberoptic intubation of a small infant with Treacher Collins Syndrome using the technique described by Ellis et al.

Improving styletted oral tracheal intubation: rational use of the OTSU

PURPOSE: To introduce an improved method of styletted oral laryngoscopic tracheal intubation. DESCRIPTION OF THE TECHNIQUE: The oral tracheal stylet unit (OTSU) is constructed using a commonly available intubating stylet combined with an ordinary endotracheal tube (ETT). The ETT/stylet is created by a series of specific steps to form an OTSU, each with a standard shape and design that allows the tracheal tube to separate freely from the stylet. After construction, every unit is tested to confirm that the frictional resistance created by the tracheal tube, as it slides along the stationary stylet, is at an absolute minimum. Successful tracheal intubation is based on the following concepts: (a) The j-shaped OTSU, when correctly directed through the airway, passes freely from the mouth to the larynx, the laryngoscopic channel; (b) The tip of the ETT must first be placed between the vocal cords with every intubation. The tracheal tube is then launched and advanced into the trachea by sliding along and off a stationary stylette; (c) Only minimal force is required to propel the ETT during intubation; (d) Resistance to placement, launch or advancement means the tip of the OTSU has come into physical contact with the patient's airway; (e) When the epiglottis obscures the larynx, the tip of the OTSU is used to explore the hypopharynx and identify the glottis. The ability to differentiate where the ETT tip is located depends primarily on interpreting the sensations of touch and pressure transmitted from the bevel of the OTSU to the hand. Successful tracheal intubation is accomplished when all criteria for placement, launch, and advancement are met. CONCLUSION: Styletted oral tracheal intubation is well known. However, we describe an improvement of the technique, based on solid physical principles and years of experience, that should prove useful both for routine intubations and unexpected difficult airways.     

Case series: The McGrath® videolaryngoscope — an initial clinical evaluation

PURPOSE: To document tracheal intubation success rates and airway instrumentation times using the newly designed McGrath videolaryngoscope. METHODS: We prospectively recorded factors associated with difficult tracheal intubation, factors causing actual difficulty in tracheal intubation, as well as complications arising from use of the new McGrath videolaryngoscope in a series of adult patients with normal preoperative airway examinations. All patients were undergoing scheduled or elective surgery. In the first 75 patients (phase I), experience with airway instrumentation was documented, while in the second 75 patients (phase II), the time required to obtain an optimal view of the larynx was recorded, as well as the time to complete tracheal intubation. RESULTS: Ninety-eight percent of all tracheal intubations were successful using the McGrath videolaryngoscope. Cormack and Lehane grade I views were obtained in 143 patients (95%) and grade II views were achieved in six (4%). In phase II, the median time required to obtain an adequate view was 6.3 sec [interquartile range 4.7-8.7 (range 2-26.3)], and to complete tracheal intubation was 24.7 sec [18.5-34.4 (11.4-286)]. Fortynine (65%) of the tracheal intubations were completed within 30 sec, and 72 (96%) were completed within one minute. No complications were encountered in any patient. CONCLUSIONS: The McGrath videolaryngoscope is an effective aid to airway management in patients with normal airways, based upon intubation success rates and the ability to rapidly secure the airway. Its potential advantages of convenience and portability warrant further evaluation in comparison with other airway devices and in patients with difficult airways.     

Using a nasopharyngeal airway during fiberoptic intubation in small children with a difficult airway

BACKGROUND: Induction of anesthesia and tracheal intubation in small children with a difficult airway is a challenging task. We report the experience with a procedure based on sevoflurane inhalation via a nasopharyngeal airway inserted early during induction before airway obstruction occurs. A pediatric fiberscope is used to perform a nasotracheal intubation via the opposite nostril. METHODS: All small children with suspected or known difficult airway needing tracheal intubation were scheduled for a fiberoptic intubation following the described protocol. RESULTS: In 3 years, we performed 27 successful fiberoptic guided tracheal intubations in 19 children, median age 8.2 months (1.0-39.1 months) and median weight 7.6 kg (3.0-15.0 kg). The optimal depth for placement of the nasopharyngeal airway was found to be 8.0 cm (7.0-8.5 cm) from the nostril in the first year of life and 8.5 cm (8.0-10 cm) in the second year. Oxygenation was sufficient during the entire procedure in all cases except one child who had short-lasting laryngeal spasm caused by instillation of lidocaine during light anesthesia. The duration of fiberoptic intubation was significantly shorter when performed by an experienced anesthesiologist (55 s vs. 120 s), but there was no significant correlation between the duration of fiberoscopy and oxygen saturation during fiberoscopy or endtidal CO(2) after intubation. CONCLUSION: The combination of nasopharyngeal airway and fiberoptic guided tracheal intubation seems to be a reliable and safe procedure for managing the difficult airway in small children.     

Awake tracheal intubation using the Airtraq® laryngoscope: a case series

The Airtraq^® laryngoscope (AL) is a new single use indirect laryngoscope designed to facilitate tracheal intubation in anaesthetised patients either with normal or difficult airway anatomy. It is designed to provide a view of the glottis without alignment of the oral, pharyngeal and tracheal axes. We report four cases of successful awake tracheal intubation using the AL. The first case is a patient with severe ankylosing spondylitis and the other three cases with anticipated difficult airway. An awake intubation under sedation and topical airway anaesthesia was chosen. We consider that the AL can be used effectively to accomplish an awake intubation in patients with a suspected or known difficult airway and may be a useful alternative where other methods for awake intubation have failed or are not available.     

Evaluation of the pediatric Bonfils fiberscope for elective endotracheal intubation

Background: Difficult airway management in children is a particular challenge for anesthesiologists and pediatricians. This study was designed to evaluate the performance of the recently developed pediatric versions of the Bonfils fiberscope for elective endotracheal intubation during routine surgical procedures. Methods: After approval by the institutional review board and written informed consent, 55 children (age 6 ± 4 years) scheduled for elective minor surgical procedures were enrolled. Nineteen children received atropine before the intubation attempt, while in the remaining 36 children, no antisialogogue was used. For endotracheal tubes up to 3.5 mm internal diameter, a fiberscope with outer diameter (OD) 2 mm, and for larger endotracheal tubes, a fiberscope OD 3.5 mm was used. Time to intubation and failure rate were obtained. Results: In the 36 children without and the 19 children with atropine pretreatment, the success rate for tracheal intubation on the first attempt was 69%/78% (25/15 patients). 4/3 patients and 2/0 patients were intubated after two and three attempts, respectively, and in 5/1 patients (14%/5%) intubation failed even after three attempts. Time to intubation was median 58/60 s, 25th–75th percentile 35–100/32–110 s, and range 14–377/18–360 s. In both groups, failed intubations were because of the secretions contaminating the optic aperture. Conclusions: High failure rate and increased intubation times suggest that the pediatric Bonfils fiberscope has significant drawbacks when used for intubation of normal pediatric airways.     

Management of difficult pediatric airway

Anesthesiologists should be familiar with the management of airway and be able to recognize and identify potential difficult airway. These entities include congenital craniofacial deformities with micrognathia (e.g. Robin sequence, Treacher Collins, Goldenhar's, Crouzon's syndromes) and metabolic diseases causing the deposit of accumulated by-products (e.g., Hurler's, Morquio's, Beckwith-Wiedemann syndromes). Cormack and Lehane grades 3 and 4 at laryngoscopy are an indication for advanced techniques for intubation. The laryngeal mask airway (LMA) and fiberscope with a directable tip are useful and important modalities in handling difficult pediatric airway and intubation. LMA not only offers another mode of securing airway besides face mask and tracheal intubation, but also provides a conduit for tracheal intubation and a rescue airway in the CICV (cannot intubate, cannot ventilate) situations. Intubation with a fiberscope can be utilized through LMA or through a specially designed face mask. Face mask designed for fiberoptic intubation has a 15 mm port for connection with the breathing circuit and another 22 mm port covered with a rubber membrane through which the fiberscope is introduced and directed to the larynx and trachea followed by the tracheal tube while ventilating and anesthetizing the pediatric patients with inhalational anesthetics. Getting used to these two modalities, LMA and fiberoptic intubation of the trachea, gives a great advantage in handling of difficult pediatric airway and intubation.     

Airway Scope: early clinical experience in 405 patients

The Airway Scope (Pentax, Tokyo, Japan) is a new device used for tracheal intubation. It allows visualization of the glottis through a non-line-of sight view. The aim of the present study was to evaluate the suitability of this device for the tracheal intubation of surgical patients. In this prospective study, the Airway Scope was used for the endotracheal intubation of 405 patients by 74 airway operators. The Airway Scope allowed visualization of the glottis in all 405 patients, including those with a Cormack-Lehane view of grade III (n = 15) or grade IV (n = 1) on Macintosh laryngoscopy. All tracheal intubations using the Airway Scope were successful. The mean time to complete tracheal intubation was 42.4 ± 19.7 s (±SD; range, 13–192 s). No dental damage was encountered, though minor mucosal injury caused by the blade was experienced in 2 patients. The Airway Scope consistently permitted a better intubation environment. With its potential advantages, the Airway Scope could be an effective aid to airway management in surgical patients.     

Videolaryngoscopy vs. direct laryngoscopy use by experienced anaesthetists in patients with known difficult airways: a systematic review and meta‐analysis

Experienced anaesthetists can be confronted with difficult or failed tracheal intubations. We performed a systematic review and meta‐analysis to ascertain if the literature indicated if videolaryngoscopy conferred an advantage when used by experienced anaesthetists managing patients with a known difficult airway. We searched PubMed, MEDLINE, Embase and the Cochrane central register of controlled trials up to 1 January 2017. Outcome parameters extracted from studies were: first‐attempt success of tracheal intubation; time to successful intubation; number of intubation attempts; Cormack and Lehane grade; use of airway adjuncts (e.g. stylet, gum elastic bougie); and complications (e.g. mucosal and dental trauma). Nine studies, including 1329 patients, fulfilled the inclusion criteria. First‐attempt success was greater for all videolaryngoscopes (OR 0.34 (95%CI 0.18–0.66); p = 0.001). Use of videolaryngoscopy was associated with a significantly better view of the glottis (Cormack and Lehane grades 1 and 2 vs. 3–4, OR 0.04 (95%CI 0.01–0.15); p < 0.00001). Mucosal trauma occurred less with the use of videolaryngoscopy (OR 0.16 (95%CI 0.04–0.75); p = 0.02). Videolaryngoscopy has added value for the experienced anaesthetist, improving first‐time success, the view of the glottis and reducing mucosal trauma.     

Awake fibrecapnic intubation: a novel technique for intubation in head and neck cancer patients with a difficult airway

Awake fibreoptic intubation is the gold standard for difficult airway management but failures are reported in the literature in up to 13% of cases. In case of failure, a tracheotomy is often indicated. We describe a novel technique for intubation in head and neck cancer patients with a difficult airway that we call awake fibrecapnic intubation. The aim of this study was to investigate the feasibility of this technique. We studied prospectively 15 consecutive intubations in head and neck cancer patients before diagnostic or therapeutic surgical procedures. After topical anaesthesia, a fibrescope was introduced into the pharynx. Spontaneous respiration was maintained in all patients. Through the suction channel of the fibrescope a special suction catheter was advanced into the airway for carbon dioxide measurements. When four capnograms were obtained, the fibrescope was railroaded over the catheter and after identification of tracheal rings, a tracheal tube was placed. Tracheal intubation was successful in all patients without bleeding or complications, with a median (range) time to intubation of 3 (2-15) min. Identification of the vocal cords and glottis was difficult in four patients due to extensive anatomical abnormalities or poor visibility; even in these patients, a capnogram was obtained within 4 s.     

Lightwand guided intubation in paediatric patients with a known difficult airway: a report of four cases

The anaesthetic management of children with craniofacial abnormalities often presents unique challenges because soft tissue and bony abnormities can affect the airway and influence airway management. We report four paediatric patients with predicted difficult airways due to craniofacial abnormalities. They all had a laryngeal view of Cormack–Lehane grade IV and were impossible to intubate using direct laryngoscopy. Fibreoptic intubation was also repeatedly attempted but was not successful. All the tracheal intubations were completed using a lightwand on the first attempt in less than 30 s. We consider that lightwand guided intubation technique may be a useful alternative approach to fibreoptic intubation technique in managing the difficult paediatric airway.     

A comparison of McGrath and Macintosh laryngoscopes in novice users: a manikin study

Direct laryngoscopy using the Macintosh laryngoscope is a difficult skill to acquire. Videolaryngoscopy is a widely accepted airway management technique that may be easier for novices to learn. We compared the McGrath^® videolaryngoscope and Macintosh laryngoscope by studying the performance of 25 medical students with no previous experience of performing tracheal intubation using an easy intubation scenario in a manikin. The order of device use was randomised for each student. After brief instruction each participant performed eight tracheal intubations with one device and then eight tracheal intubations with the other laryngoscope. Novices achieved a higher overall rate of successful tracheal intubation, avoided oesophageal intubation and produced less dental trauma when using the McGrath. The view at laryngoscopy was significantly better with the McGrath. Intubation times were similar for both laryngoscopes and became shorter with practice. There was no difference in participants' rating of overall ease of use for each laryngoscope.     

Fiberoptic intubation through an I-gel supraglottic airway in two patients with predicted difficult airway and intellectual disability

We describe successful fiberoptic-guided tracheal intubation through the novel supraglottic "I-gel" airway in two uncooperative adult patients with genetic syndromes, learning disability, and predicted difficult airway, scheduled for complex dental treatment under general anesthesia. The I-gel maintained the airway immediately after induction, allowing oxygenation and ventilation. Location of the laryngeal inlet was successful on the first attempt with a fiberscope, and the tracheal tube was inserted into the trachea over the endoscope without complication in both patients. This report suggests another option for management of predicted difficult airways.     

The intubating laryngeal mask airway with and without fiberoptic guidance

We conducted this feasibility study using the intubating laryngeal mask airway (ILMA) and a polyvinyl chloride tracheal tube to compare success rates, hemodynamic effects, and postoperative morbidity with two methods of tracheal intubation. After ethics approval and informed consent, 90 healthy ASA physical status I or II women with normal airways were enrolled in the randomized, controlled study. After a standardized inhaled anesthesia induction protocol, tracheal intubations using ILMA with fiberoptic guidance (ILMA-FOB) and ILMA inserted blindly without fiberoptic guidance (ILMA-Blind) were compared with the control group of direct laryngoscopy (laryngoscopy group). All 90 patients were successfully ventilated. For tracheal intubation, success rates were equal in all three groups (97%). Total intubation times were longer for the ILMA-FOB group (77 s versus 48.5 s for laryngoscopy and 53.5 s for ILMA-Blind). The laryngoscopy group had a larger increase in mean arterial blood pressure to tracheal intubation. There were no differences in postoperative sore throat or hoarseness among the groups. In conclusion, success rates are equally high for tracheal intubation using ILMA-Blind and ILMA-FOB techniques in women with normal airways. IMPLICATIONS: The intubating laryngeal mask airway (ILMA) can be used as a primary airway for oxygenation and ventilation. Both methods of tracheal intubation using the ILMA were equally successful. Postoperative morbidity in the ILMA groups was similar to that in the laryngoscopy group. For women with normal airways, both the ILMA inserted blindly and the ILMA with fiberoptic guidance are suitable alternatives to laryngoscopy for tracheal intubation.     

Fibreoptic intubation in Klippel-Feil syndrome

A patient with Klippel-Feil syndrome who underwent abdominal surgery is presented and the anomaly reviewed. The anatomical abnormality and potentially unstable neck provide a potentially difficult tracheal intubation which was undertaken using an awake fibreoptic technique. The role of the fiberscope and the advantage of pre-operative assessment of the difficult airway are discussed.     

A ventilation-exchange bougie for fibreoptic intubations with the laryngeal mask airway

The ventilation-exchange bougie is a new airway device which can be mounted on a fibreoptic laryngoscope for passage through the larynx into the trachea via a laryngeal mask airway. Subsequent removal of the fibreoptic laryngoscope and laryngeal mask airway allows a tracheal tube to be railroaded into position over the ventilation-exchange bougie. This study described the use of this technique for elective tracheal intubation in two groups of 12 subjects in whom difficulty with intubation was not expected. All the subjects were successfully intubated by one of two anaesthetists, one experienced and the other inexperienced with fibreoptic intubation techniques. Neither had had prior experience with the ventilation-exchange bougie. Because ventilation was maintained throughout the procedure, intubation did not need to be hurried. Cusum analysis confirmed the impression of a learning curve and the technique could be considered learnt after four and six intubations for the experienced and inexperienced fibreoptic larvngoscopists respectively. No difficulty was found either in intubating the larynx with the fibreoptic laryngoscope and ventilation-exchange bougie or when railroading the tracheal tube over the ventilation-exchange bougie. It is suggested that this new device could have an important role in teaching fibreoptic techniques, management of the difficult airway and failed intubations.     

Review article: Video-laryngoscopy: another tool for difficult intubation or a new paradigm in airway management?

Background

An adequate airway management plan is essential for patient safety. Recently, new tools have been developed as alternatives to direct laryngoscopy and intubation. Among these, video-laryngoscopy has enjoyed a rapid increase in popularity and is now considered by many as the first-line technique in airway management. This paradigm shift may have an impact on patient safety.

Principal findings

Studies show that video-laryngoscopes are associated with better glottic visualization, a higher success rate for difficult airways, and a faster learning curve, resulting in a higher success rate for intubations by novice physicians. Thus, unanticipated difficult intubations may be less frequent if video-laryngoscopy is used as the first-line approach. In addition, on-screen viewing by the operator creates a new dynamic interaction during airway management. The entire operating room team can assess progress in real time, which enhances communication and improves teaching. However, if video-laryngoscopes become standard tools for tracheal intubation, these more costly devices will need to be widely available in all locations where airway management is conducted. Furthermore, algorithms for difficult intubation will require modification, and the question of selecting alternate devices will arise. If the incidence of difficult intubation decreases, the lack of motivation to teach and learn the use of alternative devices might adversely impact patient safety.

Conclusion

The greater effectiveness of video-laryngoscopes associated with multi-person visualization could enhance overall patient safety during airway management. However, the routine use of video-laryngoscopy also introduces some issues that need to be addressed to avoid potentially dangerous pitfalls.     

Utility of the Aintree Intubation Catheter in fiberoptic tracheal intubation through the three types of intubating supraglottic airways: a manikin simulation study

Purpose

The purpose of this study was to examine the utility of the Aintree Intubation Catheter (AIC) with three types of supraglottic airway devices for tracheal intubation (ISGAs) using a manikin.

Methods

Participants were 21 anesthesiologists with more than 2 years of experience in clinical anesthesia. Three types of ISGAs were passed through the glottis: Fastrack-Single Use (FSU; size 4), air-Q (size 3.5), and i-gel (size 4). Participants attempted fiberoptic tracheal intubation with the ISGAs in random order. Success rate of tracheal intubation, intubation time, and collision with the glottis were recorded. Participants also evaluated the subjective difficulty of the entire intubation process and passing the tracheal tube through the glottis using a Visual Analogue Scale.

Results

The FSU required a significantly longer time for intubation compared with the other two ISGAs (p < 0.05). AIC use did not significantly improve the success rate of intubation or shorten intubation times for any of the ISGAs. However, there were significantly more collisions with the glottis without AIC use for the FSU and air-Q compared to when they were used with the AIC (FSU, p = 0.015; air-Q, p = 0.025).

Conclusion

Among the ISGAs tested, intubation took longer with the FSU, and the FSU had a higher failure rate than the other ISGAs. AIC significantly decreased the number of collisions with the FSU and air-Q. These findings suggest that the AIC is effective in reducing collisions with the tracheal tube and thus will reduce the risk of mechanical injury to the airway.