LMA FastrachTM Research Articles

COMPARATIVE EVALUATION OF LMA CTRACH VERSUS LMA FASTRACH FOR TRACHEAL INTUBATION

Introduction: TM The intubating laryngeal mask airway (ILMA) or LMA Fastrach was invented as a ventilatory device,and TM as a conduit for blind tracheal intubation. However, intubation through LMA Fastrach requires multiple attempts. LMA TM TM CTrach is a modification of LMA Fastrach and allows intubation under direct vision via an integrated fibreoptic bundle and a detachable liquid crystal display viewer.This study was undertaken to compare the first attempt success rate of TM tracheal intubation through the CTrach laryngeal mask and LMA Fastrach . Methods and Materials:This prospective randomized study was conducted on 100 adults,ASA physical status I and II patients of either sex, scheduled to undergo general anaesthesia requiring tracheal intubation for elective surgery.The patients were randomly allocated to two groups of 50 patients each, to be intubated via CTrach (GROUP CT, n=50) or ILMA (GROUP FT,n=50).The first-attempt and overall success rates of tracheal intubation,the times taken and incidence of pharyngo-laryngeal morbidity,were recorded. Results: Tracheal intubation was successful on the first attempt in 96% of patients with the LMA CTrach™ and 84% of patients with the LMA Fastrach™ (p= 0.045). The success rates within three attempts were 100% in both groups (p=0.124).The mean time taken for the complete tracheal intubation process was 109.6 ± 38.679 seconds with the LMA CTrach™ and 118.68 ±22.342 seconds with the LMA Fastrach™ (p= 0.154). Conclusion: To conclude, both airway devices are comparable and efficacious and the overall success of tracheal intubation was 100% in both groups.

Comparative study of fiber-optic guided tracheal intubation through intubating laryngeal mask airway LMA Fastrach™ and i-gel in adult paralyzed patients.

Background:The i-gel is a novel and innovative supraglottic airway management device used both as an airway rescue device and as a conduit for fiberoptic intubation. In this prospective randomized study, we compared fiberoptic-guided tracheal intubation through the i-gel and LMA Fastrach™ in adult paralyzed patients.Materials and Methods:After ethical committee approval and written informed consent, 60 patients of either sex were randomly allocated to either group of supraglottic airway device (SGAD). After successful insertion of the SGAD, the fiberoptic bronchoscope (FOB)-guided tracheal intubation was done through the respective SGAD. The primary objectives were the ease and time taken for fiberoptic-guided intubation in either group. Secondary variables included time taken for successful placement of SGAD, ease of insertion of SGAD, airway seal pressure, ease and time of removal of SGAD, variation in hemodynamic parameters, and complications if any.Results:Time taken for tracheal intubation in LMA Fastrach™ group was 69.53 ± 5.09 s and for the i-gel group it was 72.33 ± 6.73 s. It was seen that it was easy to insert the endotracheal tube (ETT) in 93.3% patients in the LMA Fastrach™ group and 96.7% patients in the i-gel group. Airway seal pressure was higher for the LMA Fastrach™ group. Both the SGADs were comparable in the number of attempts of insertion, ease of insertion, and insertion time. In addition, the hemodynamic variables noted did not show any increase after insertion of SGAD. There was no difficulty encountered in removal of either SGAD.Conclusion:I-gel may be a reliable and cost-effective alternative to LMA Fastrach™ for fibreoptic-guided tracheal intubation.

Air-Q ® versus LMA Fastrach™ for fiberoptic-guided intubation: A randomized cross-over manikin trial

Abstract Introduction Airway management is still a major cause of anaesthesia-associated morbidity and mortality. Supraglottic devices are recommended in difficult airway management guidelines. The aim of this study was to compare the performance of the Air-Q® and the LMA Fastrach™ for fibreoptic guided tracheal intubation. Methods Thirty-three anaesthesia trainees participated in this randomized crossover study. Time to insert the dedicated airways (insertion of the airway into the manikin and delivery of two breaths), time to tracheal intubation (fibreoptic-guided tracheal intubation), time to remove the dedicated airway (removal of the Air-Q®/LMA Fastrach™ over the tracheal tube) and the opinion of the ease of use of the anaesthesia trainees were measured. Results There was 100% success rate for tracheal intubation with both devices on the first attempt. Time to insert the dedicated device and deliver two breaths was 10 ± 3 s for the Air-Q® and 11 ± 3 s for the LMA Fastrach™, p = 0.07. Time taken to intubate the trachea was shorter with the Air-Q®, 38 ± 15 s, than with the LMA Fastrach™, 47 ± 19 s, p = 0.017. Overall procedure time was significantly shorter with the Air-Q® as compared with the LMA Fastrach™, with a mean time of 74 ± 21 s and 87 ± 28 s respectively, p = 0.002. Air-Q® removal was considered easier than LMA Fastrach™ removal, p = 0.005. There were no tube dislodgements during the removal of the dedicated airways. Conclusions Inexperienced anaesthesia residents can perform fibreoptic-guided intubation through Air-Q® and LMA Fastrach™ in a clinically acceptable time with high success.

Estudio aleatorizado cruzado para evaluar la intubación guiada con fibrobroncoscopio a través del dispositivo Air-Q® versus la mascarilla laríngea Fastrach™ en maniquís

IntroductionAirway management is still a major cause of anesthesia-associated morbidity and mortality. Supraglottic devices are recommended in difficult airway management guidelines. The aim of this study was to compare the performance of the Air-Q® and the LMA Fastrach™ for fiberoptic guided tracheal intubation. MethodsThirty-three anesthesia trainees participated in this randomized crossover study. Time to insert the dedicated airways (insertion of the airway into the manikin and delivery of two breaths), time to tracheal intubation (fiberoptic-guided tracheal intubation), time to remove the dedicated airway (removal of the Air-Q®/LMA Fastrach™ over the tracheal tube) and the opinion of the ease of use of the anesthesia trainees were measured. ResultsThere was 100% success rate for tracheal intubation with both devices on the first attempt. Time to insert the dedicated device and deliver two breaths was 10±3s for the Air-Q® and 11±3s for the LMA Fastrach™, P=.07. Time taken to intubate the trachea was shorter with the air-Q®, 38±15 s, than with the LMA Fastrach™, 47±19s, P=.017. Overall procedure time was significantly shorter with the Air-Q® as compared with the LMA Fastrach™, with a mean time of 74±21s and 87±28s respectively, P=.002. Air-Q® removal was considered easier than LMA Fastrach™ removal, P=.005. There were no tube dislodgements during the removal of the dedicated airways. ConclusionsInexperienced anesthesia residents can perform fiberoptic-guided intubation through Air-Q® and LMA Fastrach™ in a clinically acceptable time with high success.

Comparison of Intubating Supraglottic Airways LMA Fastrach™ and ILTS-D® under Normal and Simulated Difficult Airways — a Manikin Study

Objectives. The goal of study was to compare the effectiveness of using Fastrach ™ and iLTS-D® on a manikin by novices 1st year resident-anesthesiologists under normal and simulated difficult airways. Material and Methods. At the first stage the participants conducted four consecutive trials on a manikin. Each trial included insertion, ventilation and blind intubation the manikin using iLTS-D® and Fastrach™. ‘Time to ventilation’, ‘time to tracheal ventilation’, success rates and number of attempts were recorded for the both devices. At the second stage participants performed one attempt of ventilation and blind intubation under simulated difficult airways (midline head stabilization and limited mouth opening 3 cm). It was estimated the difference between devices in ‘time to ventilation’ and ‘time to tracheal ventilation’; differences in success rates at trial 4 and at the second stage. Results. There was no difference in ‘time to ventilation’ between either device in trial 4 (median: Fastrach: 14.7 s, iLTS-D: 13.2 s, p = 0.14). Also there was no difference in ‘time to tracheal ventilation’ between either device in trial 4 (median: Fastrach: 15.4 s., iLTS-D: 13.9 s, p = 0.55). Both devices were equally effective in a simulated difficult airway, ventilation and intubation at the first attempt was successful in all cases, there was no significant difference in ‘time to ventilation’ (Fastrach: 12.3 s, iLTS-D: 13.5 s, p = 0.14) and ‘time to tracheal ventilation’ (Fastrach: 12.6 s, iLTS-D: 12.5 s, p = 0.77).

Concluding results from the first phase of the Zurich Unexpected Difficult Airway course based on exercise of technical skills.

We analysed the results of the first phase of the Zurich Unexpected Difficult Airway course. Two hundred and twenty-eight staff members performed a total of 2712 standardised airway rescue procedures with four airway devices: SensaScope™, LMA Fastrach™, Laryngeal Tube and needle cricothyrodotomy. Four consecutive attempts were performed using each device. We analysed the success rate and the time needed for successful completion for each attempt and device. The success rates and mean (SD) completion times for all participants were 96.2% and 30.2 (15.3) s for the SensaScope, 88.1% and 40.4 (17.2) s for the LMA Fastrach, 99.0% and 12.1 (10.6) s for the Laryngeal Tube and 99.0% and 12.3 (6.1) s for needle cricothyroidotomy. The learning curves resulting from the four consecutive attempts with each device showed a clear pattern of improvement. This institutional airway training course represents a promising method to improve the capability of practitioners to cope with unexpected difficult airway situations.

Comparison of success rate of blind intubation through Air-Q and LMA FastrachTM in sniffing position and neutral position

Comparison of success rate of blind intubation through Air-Q and LMA FastrachTM in sniffing position and neutral position

Längenverhältnis von Trachealtubus zur Larynxmaske

Management of difficult airways and difficult intubation differs in pediatric and in adult patients. In conscious children, fiberoptic intubation is not feasible because of limited compliance. The specially designed laryngeal mask for blind tracheal intubation, LMA Fastrach™, is available for adolescents and adults only. Therefore, fiberoptic-guided intubation through a supraglottic airway device (SAD) is a standard technique for the management of difficult intubation in children. While performing the procedure, stabile positioning of the endotracheal tube (ETT) and prevention of dislodgement are critical issues. The relationship between the length of the ETT and the SAD is highly important and was investigated in this in vitro study.In this study 6 different brands of SAD in the pediatric sizes 1-3 and 2 different ETT brands (cuffed, Microcuff(®), uncuffed, Sheridan PED-SOFT™) were investigated. Using pediatric growth tables, the recommended patient weight for each SAD size was correlated to patient age and then to appropriately sized cuffed and uncuffed ETTs. The ETT size was chosen according to the manufacturer's recommendations (cuffed ETT) and according to the literature (uncuffed ETT). The various SAD-ETT pairs were assessed with regard to differences in their length. After lubrication with silicone the ETT with a firmly attached 15 mm tube adapter was maximally inserted into the SAD and the ETT tip overlapping the SAD cuff was measured. Secondarily, an adapter for fiberoptic procedures was interposed and the measurements repeated.For a defined patient uncuffed ETTs were usually selected with a larger internal diameter (ID) compared to cuffed ETTs. Therefore, the uncuffed ETT is the longer one and will overlap the SAD by a longer tip. Comparing the curved SAD brands AuraOnce™ and Aura-i™, the Aura-i™ devices generally showed shorter tubes resulting in a longer protruding ETT tip (median 1.5 cm, minimum-maximum 1.0-2.4 cm). The straight brands LMA classic™, AuraStraight™ and LMA Unique™ showed similarity in tube length. In comparison with i-gel(®), for the SAD sizes 1-2.5 the former provide a longer projecting ETT tip. Only i-gel(®) together with AuraStraight™ showed the longest overlapping ETT tip for SAD size 3. If a swivel adapter was used during the fiberoptic intubation procedure, the length of the ETT could be critically reduced in relation to the length of the SAD. Using a swivel adapter from VBM Medizintechnik, (Sulz a. N., Germany) a relative reduction in ETT length of 2.3 or 3.2 cm has to be taken into account.For fiberoptic-guided endotracheal intubation through an SAD, sufficient length of the ETT in relation to the SAD is mandatory. Differences in geometry between SAD and ETT brands have to be considered. The selection of a relatively small SAD in combination with an uncuffed ETT might be advantageous. Redesigned extra long ETTs would be desirable to decrease the risk for ETT dislocation and to increase the safety of the technique. Restrictive use of a swivel adapter during the procedure is important because of further and potentially critical decreases in ETT length. In addition, after successful intubation of the trachea, removal of the SAD via an airway exchange catheter and replacement of the cuffed ETT of choice in the correct position is recommended to secure the airway and provide unimpaired ventilation and oxygenation.

Simulating face-to-face tracheal intubation of a trapped patient: a randomized comparison of the LMA Fastrach™, the GlideScope™, and the Airtraq™ laryngoscope

We undertook a prospective randomized comparison of the LMA Fastrach™, Airtraq™ laryngoscope, and GlideScope™ used for face-to-face tracheal intubation simulated to mimic an entrapped patient. Thirty senior emergency medicine physicians were trained in the use of the LMA Fastrach™, GlideScope™, and Airtraq™ laryngoscope with a standard airway trainer manikin (control). Participants were then asked to perform tracheal intubation in two difficult situations simulated on a difficult airway management manikin wearing a cervical collar. In Situation 1, the manikin was in the supine position with a difficult airway caused by stiffening the cervical spine. In Situation 2, the manikin was positioned to simulate face-to-face tracheal intubation. We measured intubation times, success rates for tracheal intubation, and the difficulty of tracheal intubation. Values are means (sd). In control and Situation 1, tracheal intubation details were similar. In Situation 2, face-to-face tracheal intubation success rate was increased with the Airtraq™ (100%), when compared with that of the GlideScope™ (70%, P<0.05) and LMA Fastrach™ (83%, P<0.05). Face-to-face tracheal intubation was less difficult (visual analogue scale: 0-100) with the Airtraq™ 11 (6) when compared with the GlideScope™ [33 (14) s, P<0.01)] and LMA Fastrach™ [22 (21) s, P<0.01]. The face-to-face tracheal intubation time was shorter with the Airtraq™ 14 (6) s than with the GlideScope™ [27 (18) s, P<0.01] and Fastrach™ [28 (10) s, P<0.01]. The Airtraq™ laryngoscope was superior to both the GlideScope™ and LMA Fastrach™ during simulated face-to-face difficult tracheal intubation.

Comparison of blind tracheal intubation through the intubating laryngeal mask airway (LMA FastrachTM) and the Air‐QTM

This study assessed two disposable devices, the LMA Fastrach™ and the newly developed supraglottic airway device, the Air-Q™, as a conduit for tracheal intubation in 154 healthy adults undergoing elective surgery. Using a non-inferiority approach, the primary outcome measure was successful tracheal intubation within two blind insertion attempts. Successful blind intubation after two attempts was achieved in 75/76 (99%) of the patients in the LMA Fastrach group vs 60/78 (77%) in the Air-Q group (95% CI for the difference 12-32%, p<0.0001). Fibreoptic intubation was used to assist the third attempt. The rate of successful intubation after three attempts was 100% in the LMA Fastrach group and 95% in Air-Q group. The single-use LMA Fastrach appears superior compared with the Air-Q, as a conduit to facilitate blind tracheal intubation.

The LMA CTrach ™ in Patients with Difficult Airways

THE LMA CTrach™ system (The Laryngeal Mask Company, Singapore) was developed from the LMA Fastrach™ system (The Laryngeal Mask Company) and consists of an LMA CTrach™ airway with fiberoptic channels and a detachable liquid crystal display viewer cum light source. The LMA CTrach™ enables ventilation, glottis visualization, and tracheal intubation via a laryngeal mask conduit. 1 In this report, we describe our experience with the LMA CTrach™ in 48 patients with difficult airways.

Prediction of a Low Success Rate of Astronauts in Space in Performing Endotracheal Intubation

We certainly concur with Rabitsch et al. 1that tracheal intubation using direct laryngoscopy by astronauts in space is likely to have a high failure rate. Roan first presented this concept and the use of the Laryngeal Mask Airway ™ (LMA ™; LMA North America, Inc., San Diego, CA) as a backup emergency airway device to the National Aeronautics and Space Administration in October 1999*and later at the Aerospace Medical Association Conference in 2001.†In fact, since 2003, the LMA-Fastrach ™ has been used on the space shuttle as a backup airway device.Several reasons exist that predict a low success rate of astronauts in space in performing tracheal intubation. Although some crew medical officers (CMOs) are physicians, often the CMO may have no medical background. The training CMOs receive on the proper use of the bag valve mask resuscitator, oral airway, tracheal intubation, and surgical cricothyroidotomy is limited, and even physician CMOs are likely to have had several years pass since the last clinical exposure to this scenario. Studies have found that experienced emergency medical technicians (basic), with two to three times the amount of training provided to CMOs, have only approximately a 50% success rate of tracheal intubation in human subjects.2,3A compounding factor further increasing the likelihood of failed intubation is the condition of microgravity while in orbit.The ideal airway for astronaut CMOs would possess a very short learning curve as well as require little experience to master and maintain proficiency. Rabitsch et al. 1chose the Esophageal Tracheal Combitube® (Kendall Sheridan Healthcare Products Company, Argyle, NY) as a backup airway device for failed tracheal intubation. Although requiring less training and skill than direct laryngoscopy, the use of the Combitube® as a rescue airway for failed intubation has shown an overall complication rate of up to 40%, including failure to place, aspiration, pneumothorax, esophageal perforation and laceration, among others.4,5Also, the presence of two lumens may prove confusing to the relative novice under the many stressors of an emergency; clearly, the wrong lumen choice would have disastrous consequences.Although an oral airway and manual resuscitator with facemask is another option, it is well known that ventilation with this device can be challenging for even the most highly trained personnel. On the other hand, 100% of 32 nurses without previous experience in the use of the LMA ™ were able to successfully ventilate live patients 3 months after manikin-only training.6The complication rate of the LMA ™ is quite low, and when used as a primary airway rescue device for failed intubation, it has provided rescue ventilation without complication in 94% of failed intubation cases.7Although the standard LMA ™ has a high success rate as a conduit for tracheal intubation, the LMA-Fastrach ™ is specifically designed to facilitate this. Therefore, it was chosen for the shuttle orbiters and the International Space Station because it most closely meets the criteria delineated above of a short learning curve with a high success rate and easily maintained insertion proficiency.‡University of Alabama at Birmingham, Birmingham, Alabama. gboyd@uab.edu

An Unusual Cause of Leak in a Silicone Endotracheal Tube Secured by the SecureEasy® Endotracheal Tube Holder in the Trauma Intensive Care Unit

The LMA-Fastrach ™ (LMA North America, San Diego, CA) has been used in patients with a difficult airway, including those with an unstable cervical spine.1,2We report a case of a successful intubation via the LMA-Fastrach ™ in a patient with severe ankylosing spondylitis and an unstable C5–C6 fracture dislocation with subsequent leak around the silicone, dedicated endotracheal tube (ETT), resulting in desaturation.The 40-yr-old male patient was awake, alert, and spontaneously breathing at the time of admission. During the course of his evaluation, his breathing became progressively laborious, and tracheal intubation was requested by the trauma team. After multiple failed attempts at awake nasal and oral fiberoptic intubation and awake direct laryngoscopy, tracheal intubation was performed blindly via a size 4 LMA-Fastrach ™ after intravenous administration of 17 mg etomidate by the trauma team. The patient was transferred to the trauma intensive care unit, where the 7.0-mm-ID, silicone, dedicated ETT was secured at 26 cm at the lips with a SecureEasy® ETT holder (Smiths Medical, Dublin, OH). Four hours after the initial intubation, mechanical tidal volumes were noted to decrease slowly (200–300 ml/breath). The presumed diagnosis was a cuff leak; deflation and reinflation of the pilot balloon with 3–5 ml air attested to the integrity of the cuff. The breathing circuit was also checked and found to be intact. The leak eventually resolved. However, the problem recurred and persisted the following days in an inconsistent pattern and at variable intervals. ETT exchange was contemplated but not attempted in light of the initial difficult intubation. The patient subsequently underwent both anterior and posterior fusions of the cervical spine with halo traction placement; no intraoperative leaks were noted. On admission day 9, however, increasing leakage and episodes of desaturation led to the decision to perform a tracheostomy. In the operating room, careful listening determined the leak to be at the level of the 15-mm male connector. Application of electrical tape to the proximal end of the ETT corrected the problem.After insertion of a No. 8 Shiley® tracheostomy tube (Tyco Healthcare, Mansfield, MA), the ETT was removed, and close examination revealed several holes at the proximal end of the ETT that lined up with the metal prongs of the SecureEasy® device (fig. 1). The ETT cuff was found to be intact. It was also noted that the 15-mm connector was from a 6.5-mm-ID ETT.The LMA-Fastrach ™ manufacturer was contacted and informed of the events. After reviewing all relevant information and photographs, the manufacturer of the LMA-Fastrach ™ stated that the problem we encountered had never been previously reported to LMA North America (as of October 2005). Several factors seem to have contributed to the leak in the ETT. The soft medical grade silicone of the dedicated ETT supplied with the LMA-Fastrach ™ can be torn or perforated by prolonged contact with sharp or pointed objects. The respiratory care department at our institution has used the SecureEasy® for some time without incident. We assume that the metal prongs do not perforate or otherwise damage the standard polyvinylchloride ETT. Moreover, tension exerted on the soft silicone ETT by inadequately supported ventilator tubing could have stretched open the small perforations and may have accounted for the inconsistent nature of the leak. Finally, the leak was further compounded by the inadvertent use of an incorrectly sized 15-mm male ETT connector.In conclusion, our unique case raises concerns about the long-term use of the silicone ETT packaged with the LMA-Fastrach ™ in the critical care unit in conjunction with the SecureEasy® ETT holder.*Advocate Illinois Masonic Medical Center, Chicago, Illinois. ninos-j.joseph@advocatehealth.com

The LMA Fastrach™ facilitates fibreoptic intubation in oral cancer patients

To compare ease of endotracheal intubation with the Intubating Laryngeal Mask Airway (ILMA) tracheal tube (TT; for LMA-Fastrach) and regular PVC TT (Portex) for nasotracheal fibreoptic intubation in oral cancer patients with a difficult airway. 40 patients of physical status ASA I-II with a history of previous oral cancer surgery and/or postoperative radiotherapy scheduled for oral cancer surgery were randomly allocated by sealed envelopes to undergo tracheal intubation with either the ILMA TT or a standard TT. Ease of nasal passage of the TT and ease of tracheal intubation over the fibrescope was assessed. Peak airway pressures were assessed intraoperatively and postoperatively for 12 hr. The use of the ILMA TT increased the ease of nasotracheal intubation by increasing the percentage of successful tube placements at the first attempt (80%) in comparison with standard TT (35%); (P < 0.05). Peak airway pressures were found to remain low with the ILMA TT. None of the patients experienced any airway related complications. Use of a soft, flexible, nonkinking ILMA TT with a tapered tip design facilitates passage into the trachea over a fibreoptic bronchoscope and allows maintenance of lower airway pressures. The ILMA TT may be a useful adjunct for management of the difficult airway in oral cancer surgery.

Impact du grade de Cormack et Lehane sur l'utilisation du masque laryngé Fastrach™ : étude en chirurgie gynécologique

Objective. – To evaluate the impact of Cormack and Lehane grade on the Intubating Laryngeal Mask Airway (LMA-Fastrach ™) using in women. Study design. – Open prospective study. Patients. – The study included 115 scheduled gynaecologic surgery women. Methods. – An LMA-Fastrach ™ was systematically performed in patients with a Cormack's grade ≥ 3 or when Arné's score was ≥ 7 whatever the Cormack. After induction of anaesthesia and neuromuscular blockade, Cormack's grade was assessed and LMA-Fastrach ™ was inserted. Proper insertion was confirmed by the easiness of assisted ventilation and the normal aspect of the capnographic curve. Intubation through the LMA-Fastrach ™ was carried out with the specific kit's endotracheal tube. More than two attempts were considered as a failure of the technique and an alternative method was performed. The following parameters were noted: age, weight, height, clinical predictors for difficult intubation (Arne et al.'s score), number of LMA-Fastrach ™ insertion, ventilation efficiency through LMA-Fastrach ™, successful intubation with LMA-Fastrach ™ and oesophageal intubation. Results. – Ventilation through the LMA-Fastrach ™ was efficient in 97%. The success rate of intubation was 94.8% (86% on the first attempt). The success rate of ventilation and intubation were not statistically different according to the different Cormack's grades. The obesity (BMI > 30) did not change the success rate of ventilation and intubation through the LMA-Fastrach ™. Conclusion. – In women with either predicted or unpredicted difficult intubation, the success rates of ventilation and intubation through the LMA-Fastrach ™ don't seem to be influenced by Cormack grade and obesity.

Room G, 10/16/2000 9: 00 AM - 11: 00 AM (PS) Successful Use of LMA Fastrach™(FT) in Patients with Obstructive Sleep Apnea Syndrome and Predictive Signs of Difficult Airway

<b>Room G, 10/16/2000 9: 00 AM - 11: 00 AM (PS) Successful Use of LMA Fastrach™(FT) in Patients with Obstructive Sleep Apnea Syndrome and Predictive Signs of Difficult Airway</b>