Reduced hemodynamic responses to tracheal intubation by the Bonfils retromolar fiberscope: a randomized controlled study

The Bonfils retromolar intubation fiberscope is a rigid endoscope designed to enable glottic visualization and facilitate intubation under endoscopic vision. Theoretically, avoiding direct-vision laryngoscopy and thus could produce less stimulation during intubation than the conventional direct laryngoscopic procedure. This prospective randomized study was designed to compare the effect of tracheal intubation with direct vision laryngoscopy (Macintosh blade) and the Bonfils retromolar intubation fiberscope on the hemodynamic responses in ASA I patients. Forty patients scheduled for elective surgery and requiring endotracheal intubation were randomly allocated to one of two groups according to the intubating tool under sevoflurane nitrous oxide Anaesthesia (n=20 each). The retromolar group received tracheal intubation with the Bonfils retromolar fiberscope, while the direct laryngoscopy group received tracheal intubation by the direct vision laryngoscope (Macintosh blade). Heart rate and arterial blood pressure (systolic BP, diastolic BP, mean ABP) were recorded before induction of Anaesthesia, 3 minutes after induction of Anaesthesia (before intubation) and 5 successive recordings at one-minute interval after intubation. All the systolic BP, diastolic Bp, mean ABP and heart rate values in the direct laryngoscopy group were significantly higher in the 5 successive minutes after intubation in comparison with the retromolar group (P = 0.00). This might be attributed to the gentle intubating technique, by the Bonfils retromolar fiberscope, which allows quick endotracheal intubation without manipulations of the base of the tongue or epiglottis.     

A comparison of bonfils fiberscope‐assisted laryngoscopy and standard direct laryngoscopy in simulated difficult pediatric intubation: a manikin study

Introduction: Difficult airway management in children is challenging. One alternative device to the gold standard of direct laryngoscopy is the STORZ Bonfils fiberscope (Karl Storz Endoscopy, Tuttlingen, Germany), a rigid fiberoptic stylette‐like scope with a curved tip. Although results in adults have been encouraging, reports regarding its use in children have been conflicting. We compared the effectiveness of a standard laryngoscope to the Bonfils fiberscope in a simulated difficult infant airway. Methods: Ten pediatric anesthesiologists were recruited for this study and asked to perform three sets of tasks. For the first task, each participant intubated an unaltered manikin (SimBaby ^TM, Laerdal, Puchheim, Germany) five times using a styletted 3.5 endotracheal tube (ETT) and a Miller 1 blade (group DL‐Normal). For the second task, a difficult airway configuration simulating a Cormack‐Lehane grade 3B view was created by fixing a Miller‐1 blade into position in the manikin using a laboratory stand. Each participant then intubated the manikin five times with a styletted 3.5 ETT using conventional technique but without touching the laryngoscope (group DL‐Difficult). In the third task, the manikin was kept in the same difficult airway configuration, and each participant intubated the manikin five times using a 3.5‐mm ETT mounted on the Bonfils fiberscope as an adjunct to direct laryngoscopy with the Miller‐1 blade (group BF‐Difficult). Primary outcomes were time to intubate and success rate. Results: A total of 150 intubations were performed. Correct ETT placement was achieved in 100% of attempts in group DL‐Normal, 90% of attempts in group DL‐Difficult and 98% of attempts in BF‐Difficult. Time to intubate averaged 14 s (interquartile range 12–16) in group DL‐Normal; 12 s (10–15) in group DL‐Difficult; and 11 s (10–18) in group BF‐Difficult. The percentage of glottic opening seen (POGO score) was 70% (70–80) in group DL‐Normal; 0% (0–0) in group DL‐Difficult; and 100% (100–100) in group BF‐Difficult. Discussion: The Bonfils fiberscope‐assisted laryngoscopy was easier to use and provided a better view of the larynx than simple direct laryngoscopy in the simulated difficult pediatric airway, but intubation success rate and time to intubate were not improved. Further studies of the Bonfils fibrescope as a pediatric airway adjunct are needed.     

The intubating laryngeal mask for a patient with cerebrospinal fluid rhinorrhea and pneumocephalus

A 53-year-old male was scheduled for repairs of cerebrospinal fluid (CSF) rhinorrhea and pneumocephalus under general anesthesia. He had undergone a neck clipping for a ruptured anterior communicating aneurysm 13 days before. As he had a difficult airway, Trachlight was used for successful tracheal intubation. To avoid tension pneumocephalus, an intubating laryngeal mask (ILM) was inserted with rapid sequence induction without positive pressure ventilation. A 7.0 mm ID straight silicone reinforced tube was then inserted through the ILM using a fiberscope. A fiberscope guided tracheal intubation via the ILM is recommended for patients with CSF rhinorrhea and pneumocephalus especially when the trachea is difficult to intubate under direct laryngoscopy.     

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.

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.     

Eine unerwartet schwierige Intubation

A solution to managing intubation difficulties during anaesthesia induction is described in this article. After two attempts at laryngoscopy had failed, endotracheal intubation was achieved by the combined use of a laryngoscope and the Bonfils rigid fiberscope. The successful technique involved two anaesthesiologists, one who displaced the patient's tongue to the left ventral part of the mouth with a laryngoscope and cleared the airway by suctioning, and one who accomplished the intubation using the Bonfils rigid fiberscope by following the blade of the laryngoscope to the larynx. After securing a good view of the vocal cords, the tube was successfully inserted into the trachea. The entire procedure of intubation was accomplished within 20 s.     

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.     

Direkte Laryngoskopie oder C-MAC-Videolaryngoskopie?

Background

Previous studies have shown that video laryngoscopy enhances laryngeal view in patients with apparently normal and difficult airways. The utility of the novel, portable, battery-powered C-MAC video laryngoscope is as yet unproven. It was hypothesized that in routine patients undergoing ENT surgery, the rate of glottic views considered unsatisfactory, i.e. Cormack and Lehane grades IIb, III, and IV, could be significantly reduced with the C-MAC video laryngoscope compared to direct laryngoscopy.

Methods

Following ethical approval and sample size estimates 108 consecutive patients undergoing ENT surgery under general anesthesia were studied. First, direct laryngoscopy was performed with the naked eye. The best view obtained was graded by the first anesthesiologist without looking at the video monitor. A second anesthesiologist blinded to the laryngeal view obtained under direct laryngoscopy graded the laryngeal view on the video monitor. Endotracheal intubation using Ring-Adair-Elwyn (RAE) tracheal tubes was then attempted under video-aided visualization. The tubes were not reinforced with a stylet. The C-MAC video laryngoscopy system (Karl Storz, Tuttlingen, Germany) is a novel device that can be used with Macintosh laryngoscope blades in different sizes. A camera and light source are located recessed from the tip of the blade. The camera unit sits in a handle attached to the laryngoscope blade and is connected by a wire to a TFT video monitor. It allows for both direct and indirect laryngoscopy and the low profile of the original British Macintosh blades may prove advantageous in patients with limited mouth opening.

Results

A total of 108 patients were enrolled in the study but for various reasons only 94 completed the study (post hoc power 97%). In 89 patients a size 3 Macintosh laryngoscopewas used while a size 4 blade was used in the remaining 5 patients. With direct laryngoscopy the glottic view was considered unsatisfactory in 40 patients (42%), but this was the case in only 15 patients (16%) when video laryngoscopy was used (p<0.0001). Endotracheal tube placement was successful in all but one patient where the Bonfils intubation fiberscope needed to be employed. No complications related to the C-MAC system were observed.

Conclusions

Compared to direct laryngoscopy with a Macintosh laryngoscope blade in unselected patients undergoing ENT surgery and thus patients more susceptible to an unexpected difficult airway than a general patient population, the mobile C-MAC video laryngoscope significantly enhanced laryngeal view. Using RAE tracheal tubes seems to compensate the unfavorable deviation of optical and anatomical axes when indirect laryngoscopy is performed with the C-MAC system.     

Canadian pediatric anesthesiologists prefer inhalational anesthesia to manage difficult airways: A survey

PURPOSE: To survey Canadian pediatric anesthesiologists to assess practice patterns in managing pediatric patients with difficult airways. METHODS: Canadian pediatric anesthesiologists were invited to complete a web survey. Respondents selected their preferred anesthetic and airway management techniques in six clinical scenarios. The clinical scenarios involved airway management for cases where the difficulty was in visualizing the airway, sharing the airway and accessing a compromised airway. RESULTS: General inhalational anesthesia with spontaneous respiration was the preferred technique for managing difficult intubation especially in infants (90%) and younger children (97%), however, iv anesthesia was chosen for the management of the shared airway in the older child (51%) where there was little concern regarding difficulty of intubation. Most respondents would initially attempt direct laryngoscopy for the two scenarios of anticipated difficult airway (73% and 98%). The laryngeal mask airway is commonly used to guide fibreoptic endoscopy. The potential for complete airway obstruction would encourage respondents to employ a rigid bronchoscope as an alternate technique (17% and 44%). CONCLUSION: Inhalational anesthesia remains the preferred technique for management of the difficult pediatric airway amongst Canadian pediatric anesthesiologists. Intravenous techniques are relatively more commonly chosen in cases where there is a shared airway but little concern regarding difficulty of intubation. In cases of anticipated difficult intubation, direct laryngoscopy remains the technique of choice and fibreoptic laryngoscopy makes a good alternate technique. The use of the laryngeal mask airway was preferred to facilitate fibreoptic intubation.     

Fibreoptic nasal intubation in children with anticipated and unanticipated difficult intubation

The establishment of a tracheal airway with direct laryngoscopy can be either a very difficult or an impossible task in children with congenital or acquired facial malformations. Out of 46 patients categorized as difficult tracheal intubation, fibreoptic laryngoscopy was used successfully in 44 children anaesthetized by mask with sevoflurane and oxygen or by an intravenous infusion of propofol and mask oxygenation. There were two failures (4.3%). One was due to excessive bleeding and secretions produced by the multiple attempts to intubate with direct laryngoscopy and the other failure in a patient with Pierre Robin syndrome and very small nasal passages that precluded the introduction of the endoscope. Fibreoptic laryngoscopy was successful in 37 cases (80.4%) on the first attempt to intubate and in seven (15.2%) on a second or third attempt. We conclude that fibreoptic laryngoscopy in anaesthetized children with difficult anticipated or unanticipated tracheal intubation in trained hands is a safe technique that can be lifesaving. Therefore, we urge all anaesthesia trainees to become proficient in fibreoptic tracheal intubation.     

Endotracheal intubation with a gum-elastic bougie in unanticipated difficult direct laryngoscopy: comparison of a blind technique versus indirect laryngoscopy with a laryngeal mirror

We evaluated the efficacy of intubation over a gum-elastic bougie by using either a blind technique or indirect laryngoscopy with a laryngeal mirror in patients with unexpected difficult direct laryngoscopy. In a prospective study, 60 consecutive patients with an unexpected Grade III or IV direct laryngoscopy were randomly allocated for intubation with a gum-elastic bougie either blindly (Group 1) or by indirect laryngoscopy with a laryngeal mirror (Group 2). We evaluated the failure rate of each method of intubation, complications related to either method, and the time required for intubation. Out of 725 patients evaluated over a 2-mo period, 60 patients (8.3%) had a Grade III laryngoscopy, and 30 of these were randomized into each group. There were 8 failed intubations in Group 1 compared with 1 failed intubation in Group 2 (P < 0.05). All eight failures in the blind intubation group ended with esophageal intubation. No additional complications were noted in either group. The time required for endotracheal intubation with each group was not significantly different (45 +/- 10 s versus 44 +/- 11 s). We conclude that intubation with a gum-elastic bougie had a lower failure rate using indirect laryngoscopy with a laryngeal mirror than a traditional blind technique. IMPLICATIONS: We evaluated the efficacy of intubation over a gum-elastic bougie by using either a blind technique or a laryngeal mirror. Intubation with a gum-elastic bougie had a lower failure rate using indirect laryngoscopy with a laryngeal mirror (P < 0.05) than a traditional blind technique.     

Indirekte Laryngoskopie

Endotracheal intubation remains the gold standard for securing the airway in emergency medicine. However, difficult endotracheal intubation and complications are common during emergency intubation. In contrast to conventional direct laryngoscopy, the new generation of devices does not require direct visualization of the vocal cords for endotracheal tube placement. These devices allow a better glottic view and successful endotracheal placement of the tube, especially if direct laryngoscopy is difficult. Recent studies showed that utilization of these devices can be easily learned. The technique of indirect laryngoscopy is currently used for securing the airway in daily anesthesia routine as well as for managing the difficult airway in the operating room. This article gives an overview of available devices for indirect endotracheal intubation as well as the current literature.     

Management choices for the difficult airway by anesthesiologists in Canada

PURPOSE: This study assessed difficult airway management, training and equipment availability among Canadian anesthesiologists. METHODS: A postal survey of active members of the Canadian Anesthesiologists' Society was conducted in 2000. Respondents chose an induction condition and intubation technique for each of ten difficult airway scenarios. Availability of airway devices in their workplaces was assessed. Chi square analyses were used to compare groups. A P value of < 0.05 was considered statistically significant. RESULTS: Eight hundred and thirty-three of 1702 (49%) surveys were returned. Staff comprised 88%, and residents 12%. Fifty-five percent had attended a difficult airway workshop within five years and 30% received mannequin airway training during residency. Direct laryngoscopy (48%) or fibreoptic bronchoscopy (34%) were the preferred techniques for intubation. For laryngeal, subglottic and unstable cervical spine scenarios, awake intubation with fibreoptic bronchoscope was most widely chosen. Asleep intubation with direct laryngoscopy was most commonly selected for trauma scenarios. Availability of difficult airway equipment varied between regions and types of hospital. Cricothyroidotomy equipment and difficult airway carts were not universally available. CONCLUSIONS: Our survey assessed current preferences, training and equipment availability for the difficult airway amongst Canadian anesthesiologists. Direct laryngoscopy and fibreoptic bronchoscopy were the preferred technique for intubation despite widespread availability of newer airway equipment. Lack of certain essential airway equipment and difficult airway training should be addressed.     

Case report of the use of videolaryngoscopy in thyroid goiter masses: An airway challenge

IntroductionThe use of videolaryngoscopy continues to play a larger role in the approach to patients with airway pathology. Looking specifically at patients with potential difficulty in ventilation and intubation due to thyroid goiter, video laryngoscopy may provide a faster and easier technique to secure the airway compared to direct laryngoscopy.Presentation of caseIn the case we will present to you, a 60-year-old female with a large goiter presented to a community hospital emergency room where she was found to be in respiratory distress with increased work of breathing. Urgent subtotal thyroidectomy was planned. The patient was intubated using a Glidescope technique and the airway was secured in a safe and timely fashion.Discussion/ConclusionA literature review of PubMed and Web of Science of the use of videolaryngoscopy in goiter, difficult airway, and airway obstruction yielded information supporting the use of the video laryngoscopy as a first choice for laryngoscopy with a proven benefit over direct laryngoscopy.     

Intubation in a patient with lingual tonsil hypertrophy using an intubating laryngeal mask airway in combination with fiberoptic intubation

A 66-yr-old man was scheduled for colon resection under general anesthesia. There were no findings suggesting difficulty of airway management. After induction of anesthesia, manual ventilation via a facemask was suboptimal, but increased fresh gas flow improved it. At direct laryngoscopy after achieving muscular relaxation, the arytenoids and epiglottis could not be seen even by an expert anesthesiologist. Intubating laryngeal mask airway (ILMA) was inserted to patient's larynx and ventilation could be continued. Tracheal intubation through ILMA was impossible because of hard resistance for inserting the endotracheal tube. Fiberoptic bronchoscopy revealed that the hypertrophied lingual tonsil obstructed the aperture of ILMA. Several attempts were made for intubation using fiberoptic tracheal intubation technique through ILMA and finally the patient's trachea was intubated without any bleeding or swelling of laryngeal tissues. The effectiveness of ILMA for the patient with lingual tonsil hypertrophy is still unknown, but the insertion of ILMA might be considered for safe airway management in combination with a fiberscope.     

Hypertrophy of the lingual tonsil and difficulty in airway control. A clinical case]

A male patient suffering for exertional angina was scheduled for coronary bypass. Physical examination was unremarkable except for oropharynx classified as Mallampati II. After anesthetic induction with fentanyl 10 micrograms/kg, thiopental 5 mg/kg and muscle relaxation with succynilcoline 1 mg/kg, the patient was ventilated via a face mask. Laryngoscopy revealed a bulky mass arising from the rigth base of the tongue hiding the epiglottis and all the vocal apparatus (Cormack class 4); a failed intubation caused bleeding. Facial mask ventilation became more difficult therefore, considering the task on managing the airway, a n. 4 laryngeal mask was positioned by the senior anesthetist. Two intubation attempts failed while ventilation via laryngeal mask became more and more difficult. Surgery was therefore cancelled due to inability to airway management. The mass, biopsied by an otolaryngologist, resulted to be a lingual tonsillar hyperthrophy and therefore was not removed. The patients was re-scheduled for cardiac surgery. Maintaining spontaneous breathing during light sedation, with topical anesthesia, this patient was successfully intubated over an Olympus BF P 10 bronchoscope. The patient had an uneventful operation, was regularly extubated and was discharged on the sixth postoperative day free from airway complications. Although we followed only some of the guidelines for the management of the difficult airway: a senior anesthetist was immediately called when an anatomic alteration was evident; progressive difficulty in maintaining the airway prompted the positioning of a LMA, the restoration of the spontaneous breathing and the cancellation of the elective operation had been mandatory when a class 4 Cormack was found at laryngoscopy. This situation requires an alternative approach to intubation or with the retrograde technique or with the aid of a fiberscope both maintaining spontaneous breathing.     

Direct laryngoscopy and endotracheal intubation in the prone position following traumatic thoracic spine injury

Perioperative airway management in trauma victims presenting with penetrating thoracic spine injury poses a major challenge to the anesthesiologist. To avoid further neurological impairment it is essential to ensure maximal cervical and thoracic spine stability at the time of airway manipulation (e.g., direct laryngoscopy and endotracheal intubation). Airway management in the prone position additionally increases the incidence of cervical/thoracic spine injury, difficult ventilation, and difficult airway instrumentation. Although awake fiberoptic intubation of the trachea is considered the gold standard for airway instrumentation in patients with posterior thoracic/cervical trauma, this technique requires the patient's cooperation, special equipment, and extensive training, all of which might be difficult to accomplish in emergency situations. We herein present the first reported case of an adult trauma patient who underwent direct laryngoscopy and endotracheal intubation under general anesthesia in the prone position. Although the prone position is not the standard position for airway instrumentation with direct laryngoscopy and endotracheal intubation under general anesthesia, our experience indicates that this technique is possible (and relatively easy to perform) and might be considered in an emergency situation.     

The unanticipated difficult intubation: rigid or flexible endoscope?

BACKGROUND: Unanticipated difficult intubation occurs with a frequency between 1.5% and 8.5%. The aim of this study was to compare the use of flexible versus rigid endoscopy in such a patient population, with respect to the preparation time and feasibility of each device. METHODS: During a four-year observational period, 116 patients with unanticipated difficult intubation were managed either with the flexible fiberscope (FFI group, n= 57) or the rigid Bonfils endoscope (RBI group, n= 59) on a randomized basis. RESULTS: The time required for preparing and performing the intubation was significantly shorter in the RBI group: median (IQR) 160 s (118-209 s) as opposed to 229 s (162-326 s) in the FFI group (P=0.001). There were no significant differences with respect to endoscopic visibility or quality of the intubation manoeuvre (P>0.1 each). Causes of unanticipated difficult intubation were mainly as follows: restricted movement of the head and neck (39.7%), a Mallampati class > 2 (35.3%), a short neck (31%) or a thyromental distance < or = 5 cm (28.4%). Postoperative complications associated with the intubation maneuver included slight bleeding (FFI = 8.8% vs RBI = 8.5%; NS), technical problems (12.3 vs 10.2%, NS), hoarseness (15.8 vs 15.3%, P=0.946) and dysphagia (5.3 vs 16.9%, P=0.070). CONCLUSION: Both endoscopic techniques enable quick and safe intubation. The Bonfils method could be the method of choice in cases of already relaxed patients with unanticipated difficult conventional laryngoscopy, presuming that the anaesthetist is familiar with this technique. Because the clinical re-evaluation for possible predictors of difficult intubation revealed no unknown new factors, the preoperative examination for anatomical peculiarities and being aware are the best protection against unanticipated intubation problems.     

Alternative techniques for tracheal intubation

Conventional direct laryngoscopy with the curved Macintosh blade is a fundamental skill for all anaesthetists and has been the cornerstone of airway management for many years. This technique relies on the operator aligning the oro-pharyngo-laryngeal structures and inserting an endotracheal tube into the trachea under direct vision. There is a recognized failure rate with this technique and thus alternative techniques for tracheal intubation should be available for use in difficult situations. Awake fibreoptic intubation (AFOI) remains the ‘gold standard’ method for securing the airway in an anticipated difficult intubation. Advances in optical technology over recent years have lead to the development of several rigid indirect devices, which improve glottic visualization by enabling the operator to ‘see around the corner’. With improved views at laryngoscopy these videolaryngoscopes are emerging as important tools in airway management and useful teaching and training aids.     

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.