Flexible Fiberoptic Scope Research Articles

A Comparative Study between C-MAC Video-Laryngoscope and Fiberoptic Laryngoscope in Anticipated Difficult Intubation

Abstract Background Numerous indirect laryngoscopes have been introduced into clinical practice and compared with the Macintosh laryngoscope. Most studies have described a significantly better glottic view and a higher success rate in difficult tracheal intubations for the indirect laryngoscopes. Some case reports also describe the successful use of these tools under sedation with preserved spontaneous breathing. Objective To compare the C-MAC® D-Blade video laryngoscope and the flexible fiberoptic scope for intubation of patients with anticipated difficult intubation. The primary endpoint was the time to achieve successful tracheal intubation. Secondary endpoints included glottic view at intubation and the number of intubation attempts. The study was conducted on 60 patients at the operating theatres of Ain Shams University Hospitals. Patients and Methods After obtaining approval from the Research Ethical Committee, Faculty of Medicine, Ain Shams University and informed consents from patients, 60 American Society of Anaesthesiologists I-II adult patients with El-Ganzouri risk index score (EGRI) ≥ 4 (age range, 21- 60 years) undergoing elective surgeries requiring tracheal intubation were enrolled in this prospective study at the operating theaters of Ain Shams University Hospitals from March 2022 to October 2022. Results Our results showed Duration of intubation (s) among the study groups. Duration of intubation (s) in Video laryngoscope Group ranged from 22 to 34 seconds with mean ± SD = 27.87 ± 3.74 while in Fiberoptic Group the Duration of intubation (s) ranged from 60 to 75 seconds with mean ± SD = 66.77 ± 4.24 with highly statistically significant difference (p = <.001) between the two groups and showed POGO score among the study groups. Regarding POGO score, there was a significant difference between the two studied groups (p = 0.019). C-MAC video laryngoscope had become a good alternative and was associated with visualization of laryngeal structures in shorter time as compared to traditional flexible fiberoptic laryngoscopy. Conclusion This randomized, prospective study demonstrated that the C-MAC may offer an advantage over the fiberoptic laryngoscope with respect to the time required to obtain a clear glottic view and successful placement of the tracheal tube. However, the Flexible Fiberoptic Scope offered a better visualization of the glottic opening compared to the C-MAC video laryngoscope. The use of C-MAC as a usual tool was limited as it is expensive device, and the use of fiberoptic bronchoscope needs more experience and training.

Flexible Fiber-Optic Scope Use in Retrieval Medicine: A Case Series

ObjectiveThe use of flexible fiber-optic scopes is increasing across critical care specialities, but there is limited literature on their use in retrieval medicine. This study aims to describe a case series in which flexible fiber-optic scopes were used by New South Wales Ambulance Aeromedical Operations critical care teams. MethodsA retrospective case series was performed in our service from January 1, 2019, to December 31, 2021. We searched our electronic medical retrieval database for the terms “aScope,” “Awake Fibreoptic Intubation (AFOI),” “Fibreoptic Intubation (FOI),” and “Nasal Endotracheal Tube (ETT)” to identify when a flexible fiber-optic scope was used. ResultsThere were 16 uses of flexible fiber-optic scopes during the study period. The most common procedure was awake nasal fiber-optic intubation, which was performed during 9 cases, 7 of which were successful. Other procedures performed included 4 cases of intubation through a supraglottic airway, 1 case of an asleep fiber-optic intubation, 1 case of flexible nasoendoscopy for upper airway assessment, and 1 case of fiber-optic bronchoscopy via tracheostomy. These procedures were performed by anesthetic, emergency and intensive care doctors. This case series describes 4 of these cases in more detail. ConclusionThis case series demonstrates a variety of procedural and diagnostic uses for flexible fiber-optic scopes in retrieval medicine. These procedures can have an important bearing on decision making and patient management. The training and clinical governance provided by our service in this skill appears to be safe and robust with high success rates of awake fiber-optic intubations.

Near-miss Tracheal Stenosis Secondary to Acute Intubation

ABSTRACT Tracheal stenosis is a rare and life-threatening condition. If left undiagnosed, this can lead to failed intubation, surgery postponement, or additional invasive airway management. A high index of suspicion from attending anesthesiologists due to inconsistencies between patient’s symptoms and diagnostics could lead to a more accurate diagnosis and management. This is a case of a 24-year-old female with difficulty breathing who was initially assessed as a case of glottic mass. The dilemma between the patient’s presentation and the preidentified airway obstruction led the anesthesiologist to do further investigation. A quick upper airway evaluation was done using the flexible fiber-optic scope which unexpectedly showed a 70%–80% circumferential subglottic stenosis. Management was henceforth changed to tracheal resection and reconstruction to address this new finding. Meticulous planning, preparation, and transdisciplinary approach of communication with the surgical team alongside detailed knowledge are probably the most important factors in the management of tracheal stenosis.

Cost-Effectiveness Analysis of PET-CT Surveillance After Treatment of Human Papillomavirus-Positive Oropharyngeal Cancer.

To determine the cost-effectiveness of surveillance imaging with PET/CT scan among patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma. Cost-effectiveness analysis. Oncologic care centers in the United States with head and neck oncologic surgeons and physicians. We compared the cost-effectiveness of 2 posttreatment surveillance strategies: clinical surveillance with the addition of PET/CT scan versus clinical surveillance alone in human papillomavirus-positive oropharyngeal squamous cell carcinoma patients. We constructed a Markov decision model which was analyzed from a third-party payer's perspective using 1-year Markov cycles and a 30-year time horizon. Values for transition probabilities, costs, health care utilities, and their studied ranges were derived from the literature. The incremental cost-effectiveness ratio for PET/CT with clinical surveillance versus clinical surveillance alone was $89,850 per quality-adjusted life year gained. Flexible fiberoptic scope exams during clinical surveillance would have to be over 51% sensitive or PET/CT scan cost would have to exceed $1678 for clinical surveillance alone to be more cost-effective. The willingness-to-pay threshold at which imaging surveillance was equally cost-effective to clinical surveillance was approximately $80,000/QALY. Despite lower recurrence rates of human papillomavirus-positive oropharyngeal cancer, a single PET/CT scan within 6 months after primary treatment remains a cost-effective tool for routine surveillance when its cost does not exceed $1678. The cost-effectiveness of this strategy is also dependent on the clinical surveillance sensitivity (flexible fiberoptic pharyngoscopy), and willingness-to-pay thresholds which vary by country.

Awake Fiberoptic Intubation

We may have many devices in this 21st century, which can be used to secure the airway in patients who have been predicted to have a difficult airway. There are many studies about difficult airways and suggested various devices such as flexible fiberoptic scope, video laryngoscope, and the specialized intubating laryngeal mask airway and they ended up concluding one device better than another. Furthermore, ET intubation requires continued practice and carries with it its own set of complications. Technical problems with the placement of endotracheal tubes have been the most frequent cause of anesthetic deaths in published analyses from all over the world. The basic responsibility of an anesthesiologist is to maintain adequate gas exchange in patients by securing a patent airway through a proper device. Fiberoptic bronchoscopy and intubation have the advantage of being easier, with shorter intubation time and continuous oxygenation and ventilation throughout the procedure, especially in the case of children. We report two such cases, where “Awake flexible fiberoptic-guided intubation” was considered the only desirable choice.

Alternative Technique for Nasotracheal Intubation Using a Flexible Fiberoptic Scope.

In oral maxillofacial surgery, the endotracheal tube (ETT) is often inserted nasotracheally to provide surgeons a better view and easier access to the oral cavity. Use of a flexible fiberoptic scope is an effective technique for difficult intubation. While the airway anatomy can be observed as the scope is advanced, the ETT tip cannot be observed with the traditional method. It is occasionally difficult to advance the ETT beyond the glottis as impingement of the ETT tip may occur. We devised a new nasotracheal intubation technique using a fiberoptic scope. In this novel technique, the ETT and fiberoptic scope are inserted into the pharyngeal space separately through the right and left nasal cavities. This permits continuous observation of the glottis as the ETT is advanced into the trachea. The main advantage of this technique is that the ETT tip is visualized as it is advanced, which helps avoid impingement of the ETT. If resistance is noted, the ETT can easily be rotated or withdrawn without causing laryngeal damage, leading to safe and smooth intubation. This novel technique allows advancement of the ETT under continuous indirect vision, thus minimizing contact of the ETT with the laryngeal structures and aiding in unhindered passage into the glottis.

Anesthetic Management of a Juvenile Hyaline Fibromatosis Patient With Trismus and Cervical Movement Limitation.

Juvenile hyaline fibromatosis (JHF) is a rare autosomal recessive disease characterized by the presence of tissue nodules, joint contractures, and gingival hyperplasia. With a 1-year-9-month-old female patient scheduled for a gingivectomy and excision of a lower lip mass under general anesthesia, it was anticipated that airway management would be difficult because of trismus and limited cervical movement. Intubation with video-laryngoscopic assistance could not be achieved because gingival hyperplasia and trismus prevented blade insertion and manipulation. Therefore, 2 endotracheal tubes were used: 1 used as a nasopharyngeal airway for assisted ventilation, and 1 used for intubation along with a flexible fiberoptic scope. This case demonstrated a useful method for managing ventilation and intubation in patients with JHF, particularly when the use of oral airway devices is difficult.

Difficult Airway Management in Neonates and Infants: Knowledge of Devices and a Device-Oriented Strategy.

Difficult airway management (DAM) in neonates and infants requires anesthesiologists and critical care clinicians to respond rapidly with appropriate evaluation of specific situations. Therefore, organizing information regarding DAM devices and device-oriented guidance for neonate and infant DAM treatment will help practitioners select the safest and most effective strategy. Based on DAM device information and reported literature, there are three modern options for DAM in neonates and infants that can be selected according to the anatomical difficulty and device-oriented strategy: (1) video laryngoscope (VLS), (2) supraglottic airway device (SAD), and (3) flexible fiberoptic scope (FOS). Some VLSs are equipped with small blades for infants. Advanced SADs have small sizes for infants, and some effectively function as conduits for endotracheal intubation. The smallest FOS has an outer diameter of 2.2 mm and enables intubation with endotracheal tubes with an inner diameter of 3.0 mm. DAM in neonates and infants can be improved by effectively selecting the appropriate device combination and ensuring that available providers have the necessary skills.

Difficult Airway Management in a Patient With Nicolaides-Baraitser Syndrome Who Had a Small Jaw and Limited Mouth Opening

Nicolaides-Baraitser syndrome (NCBRS) is a rare congenital genetic disorder characterized by distinctive facial features similar to Treacher Collins syndrome (TCS). We report the first case of successful nasal fiberoptic intubation in a patient with NCBRS with micrognathia and limited mouth opening due to trismus. A 9-year-old girl with NCBRS and dental caries was scheduled to undergo general anesthesia for a dental extraction. Initial attempts at oral intubation using a video laryngoscope were unsuccessful. However, subsequent attempts at nasal intubation using a flexible fiberoptic scope were successful. This report highlights that patients with NCBRS may present with difficult airways to manage and intubate.

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

BackgroundPatients with difficult airways are sometimes encountered in the emergency department (ED), however, there is a little data available regarding their management. ObjectivesTo determine the incidence, management, and outcomes of patients with predicted difficult airways in the ED. MethodsOver 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. ResultsThere 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. ConclusionsDifficult 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.

PP33 - Lung abscess isolation using double lumen tubes combined with bronchial blockers: a case series

Thoracic surgery in patients with lung infections is an absolute indication to isolate healthy lung or lobes. Different methods have been described, including the double-lumen endotracheal tube (DLT) or a variety of bronchial blockers (BBs) (1). However, when an abscess is present in only one lobe and lobectomy is planned, the insertion of a DLT alone or a single tube plus a BB may not be sufficient to prevent the spread of infection to an ipsilateral lobe. We present three cases with lung infection in which the isolation was made by combining DLT with a BB. Case 1: 22-years-old man diagnosed with lung aspergilloma within the residual tuberculous cavity in the upper left lobe. The surgeon requested selective resection of this lobe. Case 2: 50-year-old man diagnosed with lung abscess in the left lower lobe with suspected neoplasia, proposed to lobectomy. Case 3: 45-year-old woman diagnosed with lung abscess in the left upper lobe with suspected neoplasia/infection, proposed for lobectomy. In all three cases, airway management was a combination of left DLT (two Robertshaw type DL and one VivaSight DL®) with a BB, using the flexible fiberoptic scope as a guide to place the BB to the lobe that was being isolated. In case 1 a Cohen BB was used; in case 2 and 3, an Arndt BB was chosen. After BB placement, the corresponding lobes were isolated, ventilation in the rest of the ipsilateral lung was initiated. The lobes remained isolated until the bronchus resection. In thoracic anaesthesia providing satisfactory surgical exposure and maintaining adequate oxygenation is a challenge. But in these cases, isolation was even more important. Several devices are used to perform lung/lobe isolation: some experts recommend DLT for its shorter insertion time and less need for repositioning; others suggest that the BB have lower complication rates with the same efficiency (2). However, in thoracic surgery involving lung abscess the combination of both devices (DLT and BB) provides excellent isolation and results. This method prevented the spread of infection to the healthy lung with the DLT and to non-affected areas of the ipsilateral lung with the BB during airway and surgical manipulation with a favourable clinical-surgical outcome. 1. Narayanaswamy M, et al. Choosing a lung isolation device for thoracic surgery: a randomized trial of three bronchial blockers versus double lumen tubes. Anest Analg 2009; 108(4):1097-101. 2. Clayton-Smith A, et al. A comparison of the efficacy and adverse effects of double lumen endobronchial tubes and bronchial blockers in thoracic surgery: A systematic review and meta-analysis of randomized controlled trials. J Cardiothorac Vasc Anesth 2015; 29(4):955-66.

Metatropic dysplasia-a skeletal dysplasia with challenging airway and other anesthetic concerns.

Metatropic dysplasia is a rare form of skeletal dysplasia requiring multiple anesthetics for surgical and imaging procedures, most of which are orthopedic procedures. We provide centralized care to patients with skeletal dysplasia at our tertiary care pediatric hospital, and we were able to collect the largest number of metatropic dysplasia patients reported to date. The aim of this retrospective study was to describe and characterize the anesthetic difficulties in this high-risk population. Medical charts of all patients with metatropic dysplasia were reviewed to collect data, including anesthetics performed, difficulties, and complications related to the anesthetic care, co-morbid conditions, and related events. Twenty-three patients with metatropic dysplasia underwent 188 anesthetics with 61% of the anesthetics having been administered for orthopedic procedures. Fourteen of 23 (60.8%) progressively became difficult to intubate over the course of their care, with 12 out of 14 having undergone cervical spine fusion. These 14 patients had a total of 133 procedures. Sixty procedures (45.1%) had an airway described as difficult. Glidescope was the difficult airway tool most commonly used (68%) with flexible fiberoptic scope used 12% and Miller or Macintosh blade used 18% of the time. In addition to the airway difficulties, spinal canal narrowing or stenosis was widely prevalent, and no neuraxial anesthetic was performed in any of our patients. Difficult airway is the most common co-morbid condition present in patients with metatropic dysplasia, especially if their cervical spine has been fused. Familiarity with the difficulties involving the airway and its management is critical in safe and successful management of anesthesia in this high-risk population.

The effect of oral positioning on the hypopharyngeal airway.

It is generally assumed that mouth opening decreases the hypopharyngeal cross-sectional area (HA) and that tongue protrusion (TP) increases the HA. We hypothesize that a substantial number of patients do not exhibit this expected pattern. Prospective cohort conducted at a tertiary academic center. With a flexible fiberoptic scope in position, the hypopharyngeal airway was visualized and assessed in 189 patients with the mouth closed. Patients were then asked to open the mouth with the tongue in neutral position (MOTN) to determine the effect on the airway. The same methodology was used to compare the airway with the MOTN versus TP. Basic demographics, including age, gender, body mass index, and presence and severity of obstructive sleep apnea (OSA), were collected. Student t test, Mantel-Haenszel chi-square, and Cochran-Armitage analyses were assessed for significant relationships and trends with oral positions. Although mean HA decreased with MOTN (P < 0.0001), 33% of patients exhibited an increase in HA. Similarly, mean HA increased with TP (P = 0.0018); however, 38% of patients demonstrated a decrease in HA. There was no significant relationship in HA between OSA and non-OSA patients. For those with OSA, increasing severity trended toward a higher incidence of smaller HA with TP (P = 0.038). The airway is typically most obstructed with mouth opening (MOTN) and most patent with tongue protrusion (TP). Nevertheless, hypopharyngeal changes with MOTN and TP followed a paradoxical pattern in one-third of our population. This may have implications in patient selection for targeted OSA treatment. 4. Laryngoscope, 127:1471-1475, 2017.

A rare case of tracheobronchial foreign body aspiration in an adult patient admitted to the ICU: A case report and review of the literature

Abstract We report an exceedingly rare case of a foreign body (FB) discovered in the tracheobronchial tree of an adult male admitted to the intensive care unit (ICU). The patient was admitted in a state of deep coma after sustaining injuries in a road traffic accident. The head, neck and chest CT scans revealed a foreign body lodged within his tracheobronchial tree. Emergency fibre optic bronchoscopy was performed using a size 8 endotracheal tube. Multiple pieces of glass were then removed by fibre optic bronchoscope using a stone retrieval basket. This case report highlights the importance of thorough clinical and radiological evaluation of polytrauma patients. A rigid bronchoscope is the recommended treatment modality for tracheobronchial foreign body removal, followed by a flexible fibre optic scope.

Comparison of the C-MAC video laryngoscope to a flexible fiberoptic scope for intubation with cervical spine immobilization

Study ObjectiveTo compare the C-MAC video laryngoscope to the standard flexible fiberoptic scope (FFS) with an eye piece (but without a camera or a video screen) for intubation of patients undergoing cervical spine surgery with manual inline stabilization. The primary end point was the time to achieve successful tracheal intubation. Secondary end points included glottic view at intubation and number of intubation attempts. DesignProspective, randomized, single-blinded study. SettingCedars Sinai Medical Center in Los Angeles, CA. PatientsOne hundred forty patients (American Society of Anaesthesiologists physical status I-III), aged 18 to 80years undergoing elective cervical spine surgery. InterventionPatients were prospectively randomized to undergo tracheal intubation using either an FFS (n=70) or the C-MAC video laryngoscope (n=70). MeasurementsAfter performing a preoperative airway evaluation, patients underwent a standardized induction sequence. The glottic view was assessed at the time of tracheal tube placement using the Cormack-Lehane and percentage of glottic opening scoring systems. In addition, the time required for successful insertion of the tracheal tube, number of intubation attempts to secure the airway, the need for adjuvant airway devices, hemodynamic changes, adverse events, and any airway-related trauma were recorded. Main ResultsThe glottic view at the time of intubation did not differ significantly with the 2 devices; however, the C-MAC facilitated more rapid tracheal intubation compared with the FFS (P=.001). The peak heart rate response following insertion of the tracheal tube was also reduced (P=.004) in the C-MAC (vs FFS) group. ConclusionThe C-MAC may offer an advantage over the FFS with respect to the time required to obtain glottic view and successful placement of the tracheal tube in patients requiring cervical spine immobilization.

A different fibre-optic device for double lumen tube position confirmation!

Sir, The review article ‘lung isolation, one-lung ventilation and hypoxaemia during lung isolation’ by Atul Purohit et al. in the September issue was an academic treat. We would like to report a novel and alternative device for confirming double lumen tube (DLT) position. The conventional method needs a paediatric fibre-optic bronchoscope (PFOB) which may not always be available.[1,2,3] We used a flexible fibre-optic uretero-renoscope (F-URS), which has an outer diameter (OD) similar to PFOB, to confirm the DLT position [Figure 1]. Figure 1 Double lumen tube loaded on fibre-optic uretero-renoscope A 24-old-year male patient was posted for the right upper lobectomy for aspergilloma in the right upper lobe cavity as a sequel to pulmonary tuberculosis. After induction of general anaesthesia, a 39 French left-sided DLT was inserted under direct laryngoscopic vision with capnographic confirmation. A “3-step” clinical method was followed to confirm position of left DLT: The tracheal cuff was inflated and air entry was confirmed bilaterally The bronchial cuff was inflated and the tracheal lumen was clamped proximally for the left lung isolation. Bronchial lumen of the DLT was ventilated and unilateral ventilation confirmed On releasing the clamp of the tracheal lumen, ventilation was resumed bilaterally. Hence, the DLT positioning was confirmed clinically.[3] The F-URS was then passed through the tracheal lumen of the DLT, which on exit showed the carina, the right main bronchus and absence of herniation of the bronchial cuff. The two left bronchi were seen on passing the F-URS through the bronchial lumen of the DLT.[1,2,3] The F-URS can confirm placement of right-sided DLT as the working length would be adequate to visualise the right upper lobe bronchus. The F-URS we used was the E Line Compact Flexible Uretero-renoscope®, manufactured by M/S Richard Wolf, Germany-8703.524; 8/9.8 Fr, with an OD of 2.67/3.27 mm and working length of 430 mm. It costs approximately Rs. 7.5–8 lakhs. The F-URS works on fibre-optic technology similar to a FOB and is used for urosurgery as a flexible fibre-optic scope. A 39 Fr DLT accepts a FOB with 3.9–4.2 mm OD, whereas a 37 Fr DLT accepts OD of 3.5–3.9 mm. The F-URS with OD of 2.67/3.27 mm easily accepts 37 and 39 Fr DLTs [Figure 2].[1,2] Figure 2 Comparing length of double lumen tube and fibre-optic uretero-renoscope Methods used for the confirmation of the DLT are clinical, FOB and recently ultrasonography (USG).[4] The clinical method as the sole confirmatory method is inaccurate in detecting malpositions of the DLT, and may present significant intra-operative problems during one-lung ventilation.[1,2] Using a FOB aids in confirming DLT position, repositioning if necessary during surgery, visualising the operated site before DLT removal and perioperative pulmonary toileting.[2,5] Its use may be limited by non-availability, also it does not confirm deflation of non-ventilated lung.[4,5] Confirmation of lung deflation can be done by lung USG by the lung sliding and lung pulse sign. USG is dependent on availability, cost of the machine and subjective assessment of the performer.[4] Hence, FOB remains the gold standard for confirming DLT position.[1,4,5,6] The presence of a super speciality urology facility in our institute ensured the presence of the F-URS. It has a smaller OD, larger working channel, active deflection and better fibre optics due to advanced technology. The indications for its use include diagnostic procedures, management of calculus disease and endoscopic management of upper tract tumours, endoureterotomy or endopyelotomy.[7] The sterilisation procedure for the F-URS is similar to other fibre-optic devices, and hence, it can be reused for urosurgery. We would like to emphasise that this was a one time use of the F-URS for confirmation of the position of DLT in the absence of PFOB, and we do not intend to use it on a regular basis. Hence, the warranty terms and conditions would not be affected. The limitation of this device would only be its non-availability in certain institutions. We would like to draw attention to the fact that application of fibre-optic technology to broader medical specialities can be used to the patients’ advantage. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Tracheal intubation with a flexible fibreoptic scope or the McGrath videolaryngoscope in simulated difficult airway scenarios

Flexible fibreoptic endoscopic (FFE) intubation is considered the 'gold-standard' when difficult airway management is anticipated. Several videolaryngoscopes have been developed to facilitate intubation by laryngoscopy. The aim of the study was to compare the performance of the McGrath series 5 videolaryngoscope (McGrath videolaryngoscope) and the FFE for tracheal intubation in manikins with a simulated difficult airway, hypothesizing that the McGrath videolaryngoscope intubation would prove faster than FFE intubation. A randomised controlled study. The Danish Institute for medical simulation between December 2009 and June 2010. Twenty-eight anaesthesia residents participating in the Danish mandatory 3-day airway management course. All participants received instructions and training in the use of the McGrath videolaryngoscope and FFE. The participants then performed tracheal intubation on a SimMan manikin once with the McGrath videolaryngoscope and once with the FFE in three difficult airway scenarios: (1) pharyngeal obstruction; (2) pharyngeal obstruction and cervical rigidity; (3) tongue oedema. We measured successful intubations, defined as intubation within 120 s, and time to tracheal intubation. The trachea was intubated within 120 s with the McGrath videolaryngoscope in 25 out of 27 (93%), 25 out of 28 (89%) and 18 out of 28 (64%) occasions compared with 11 out of 28 (40%), 11 out of 28 (40%) and 16 out of 28 (57%) with the FFE in scenarios (1), (2) and (3), respectively. Time to tracheal intubation was shorter with the McGrath videolaryngoscope in scenarios (1) and (2) than with the FFE (Wilcoxon signed rank sum test, P < 0.0001). The McGrath videolaryngoscope is a valuable device with higher success rate and a quicker performance in simulated difficult airways. In patients, videolaryngoscopy may have a role in difficult airway algorithms, but the optimal device has yet to be found.

Awake tracheal intubation using Pentax airway scope in 30 patients: A Case series.

Background and Aims:Pentax airway scope (AWS) has been successfully used for managing difficult intubations. In this case series, we aimed to evaluate the success rate and time taken to complete intubation, when AWS was used for awake tracheal intubation.Methods:We prospectively evaluated the use of AWS for awake tracheal intubation in 30 patients. Indication for awake intubation, intubation time, total time to complete tracheal intubation, laryngoscopic view (Cormack and Lehane grade), total dose of local anaesthetic used, anaesthetists rating and patient's tolerance of the procedure were recorded.Results:The procedure was successful in 25 out of the 30 patients (83%). The mean (standard deviation) intubation time and total time to complete the tracheal intubation was 5.4 (2.4) and 13.9 (3.7) min, respectively in successful cases. The laryngeal view was grade 1 in 24 and grade 2 in one of 25 successful intubations. In three out of the five patients where the AWS failed, awake tracheal intubation was successfully completed with the assistance of flexible fibre optic scope (FOS).Conclusion:Awake tracheal intubation using AWS was successful in 83% of patients. Success rate can be further improved using a combination of AWS and FOS. Anaesthesiologists who do not routinely use FOS may find AWS easier to use for awake tracheal intubation using an oral route.

Glidescope vs. flexible fiberoptic scope for potentially difficult airway

Stratigopoulou, P.; Pantazopoulos, C.; Saridaki, A.; Stefaniotou, A.; Tsinari, K.; Lambadariou, K. Author Information

Performance of tracheal intubation with the SensaScope in severely difficult airways

This Correspondence accompanies the following article: Biro P. Performance of tracheal intubation with the SensaScope in severe difficult airway: authors’ reply. Eur J Anaesthesiol 2012; 29:56–57. Editor, In a recently published prospective randomised manikin study, Ludwig et al.1 found that in a simulated severely difficult airway, the SensaScope performed as well as in normal anatomy, whereas tracheal intubation with a direct laryngoscope proved to be impossible. This is the first study to evaluate intubation performance of the SensaScope in simulated normal and difficult airways, and their findings have a potential implication for the management of severely difficult airways. However, there are several possible limitations that can interfere with interpretation of the results of this study. First, in the severely difficult intubation scenario, a Cormack–Lehane grade 4 laryngeal view was simulated by the inflation of the manikin's tongue base with 40 ml of air. Also, intubation performance of the SensaScope was compared with that of a Macintosh laryngoscope as the control device. For this severe airway difficulty, however, tracheal intubation with a direct laryngoscope may not be a sensible choice in clinical practice. Furthermore, when direct laryngoscopy cannot expose any epiglottic structure, for example Cormack–Lehane grade 4 laryngeal view, blind tracheal intubation will also be very difficult or even impossible.2 In this case, flexible fibreoptic intubation is often considered as a ‘gold standard’ method of difficult airway management.3 The SensaScope was designed to combine the benefits of both rigid and flexible fibreoptic scopes in a single device,1,4 but the relative efficacy of the SensaScope in comparison to other fibreoptic devices, such as the fibreoptic bronchoscope, Bonfils intubation fibrescope, Shikani Seeing Optical Stylet and StyletScope,5 have not really been determined. Thus, we believe that when evaluating the intubation performance of the SensaScope in a difficult airway scenario, the rational control device should be a flexible or rigid fibreoptic scope, rather than a direct laryngoscope. Second, this is a manikin study and the difficult intubation scenario simulated in this study cannot represent all clinical situations. Actually, the cause of difficult intubation in this manikin study is a reduced oropharyngeal space. In real patients, difficult intubation often has multiple causes, such as reduced head and neck mobility, limited mouth opening, reduced mandibular space, obesity and poor dentition.6 A recognised problem with manikin studies is that the times required to perform airway interventions are generally quicker than in patients.7 By four modern manikins in several domains of airway management, Mihai et al.8 have demonstrated that tracheal intubation could not reliably be simulated by manikins. Also, a manikin lacks two major problems for any kind of fibreoptic scopes: secretions in the airway and fogging of the scope by the humidity of the breath. Currently, even the best manikin model cannot reproduce these difficulties. It has been reported that obscure vision by secretions and fogging was a cause of the difficult intubation with the SensaScope in patients with an anticipated difficult airway.9 Therefore, before the results of the study by Mihai et al. are extrapolated to clinical practice, clinical accumulation and randomised trials of the intubation performance of SensaScope vs. other promising flexible and rigid fibreoptic scopes in patients with difficult airways are needed.8 Finally, and as acknowledged in the original trial,1 one of the authors was involved in design and development of the SensaScope. This raises the possibility of an albeit unintended bias in favour of the performance of the tested study device. Acknowledgement None of the authors has received any financial support.