Luis A. Gaitini, MD*, Boris Yanovski, MD,* Somri Mustafa, MD,* Carin A. Hagberg, MD, Pedro Charco Mora, MD, and Sonia J. Vaida, MD

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1 Society for Technology in Anesthesia Section Editor: Maxime Cannesson A Feasibility Study Using the VivaSight Single Lumen to Intubate the Trachea Through the Fastrach Laryngeal Mask Airway: A Preliminary Report of 50 Cases Luis A. Gaitini, MD*, Boris Yanovski, MD,* Somri Mustafa, MD,* Carin A. Hagberg, MD, Pedro Charco Mora, MD, and Sonia J. Vaida, MD BACKGROUND: The VivaSight Single Lumen (SL) is new endotracheal tube with a video camera and a light source in the tip allowing continuous visual observation of the airway. In this study, we checked the feasibility of endotracheal intubation with a VivaSight-SL through the Fastrach Laryngeal Mask Airway (FT-LMA). METHODS: We studied 50 patients with normal airways, scheduled for elective surgery during general anesthesia requiring endotracheal intubation. The FT-LMA was inserted and once adequate ventilation was achieved, the VivaSight-SL was passed through the FT-LMA into the trachea under visual control. The following criteria were used to score the laryngeal view: grade 1: full view of the arytenoids and glottis; grade 2: epiglottis, arytenoids or glottic opening are partly visible, the structure of cords is difficult to see; grade 3: dark areas indicating an open space; and grade 4: no part of the larynx can be identified. RESULTS: The FT-LMA was placed successfully in 49 patients at the first attempt. One patient was excluded from the study after 2 failed attempts to ventilate with the FT-LMA. All 49 patients were successfully intubated with the VivaSight-SL, (95% confidence interval [CI] ), 47 patients at the first attempt (95% CI, ) and 2 patients at the second attempt. (95% CI, ). The time to achieve an effective airway with the FT-LMA was 15.4 ± 6 (mean ± SD) seconds. The time to achieve a laryngeal view with the VivaSight-SL was 28.8 ± 5 seconds. Correct position of the VivaSight-SL was confirmed with visualization of the carina. Time of successful intubation with VivaSight-SL from picking up the VivaSight-SL to observing a end-tidal CO 2 curve was 45 ± 7 seconds. After introducing the VivaSight-SL through the intubating channel of the FT-LMA, a grade 1 view was obtained in 18 patients, grade 2 in 18 patients, a grade 3 in 4 patients, and grade 4 in 9 patients. CONCLUSION: The high first-attempt intubation success rate using the VivaSight-SL to intubate the trachea through a FT-LMA makes this technique an attractive and promising concept. (Anesth Analg 2013;116:00 00) The VivaSight Single Lumen (SL; ETView Ltd, Misgav, Israel) is a polyvinyl chloride single use endotracheal tube (ETT) with an embedded complementary metal oxide semiconductor video camera and a light source in its distal portion enabling continuous From the *Department of Anesthesiology, Bnai-Zion Medical Center, Haifa, Israel; Department of Anesthesiology, The University of Texas Medical School at Houston, Houston, Texas; Department of Anesthesiology, Son Espases University Hospital, Palma de Mallorca, Spain; and Department of Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania. Accepted for publication October 1, Funding: The VivaSight-SL s were provided by ET view Ltd., Misgav, Israel. Conflict of Interest: See Disclosures at the end of the article. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal s Web site ( Reprints will not be available from the authors. Address correspondence to Luis Gaitini, MD, Department of Anesthesiology, Bnai-Zion Medical Center, 47 Golomb, St. Haifa 31048, Israel. Address to luis.gaitini@b-zion.org.il. Copyright 2013 International Anethesia Research Society. DOI: /ANE.0b013e31827b278f airway visualization 1,2 (Figs. 1 and 2). The internal diameter of the VivaSight-SL is similar to the standard 7.5 and 8 mm ETT, and it can be used with a stylet to adjust the shape of the tube. According to the manufacturer, the resistance to airflow is similar to a standard ETT (unpublished data). Images of the airway are continuously projected onto a portable monitor screen through a cable that carries the video signal from the camera. It also has a port that enables saline injection to clear the video camera. The VivaSight-SL is currently available in 3 sizes: 7.0, 7.5, and 8.0 mm. Thus far, the VivaSight-SL was used to verify the ETT position once it was in the trachea, during percutaneous nephrolithotomy and lung lobectomy as well as to exclude mainstem intubation. 1,2 We evaluated the VivaSight-SL for initial tracheal tube placement through the Fastrach Laryngeal Mask Airway (FT-LMA; LMA North America, Inc., San Diego, CA) The FT-LMA has gained a well-established role in the management of the difficult airway. 3 7 It serves as a conduit for blind, fiberoptically guided or lightwand tracheal intubation. 5,8,9 However, blind intubation frequently <zdoi; /ane.0b013e31827b278f> March 2013 Volume 116 Number 3 1

2 VivaSight Single Lumen Figure 1. VivaSight Single Lumen. fails despite corrective mask positioning maneuvers and multiple attempts at intubation. 5,10 Although fiberoptically guided intubation through the FT-LMA has a very high success rate, the technique is time consuming. 6,8 We describe the use of VivaSight-SL to facilitate endotracheal intubation through the FT-LMA. METHODS This study was approved by the local Human Ethics Committee at Bnai-Zion Medical Center, Haifa, Israel, and written informed consent was obtained from all patients. Subjects included 50 patients, aged 20 to 80 years, ASA I and II, between 155 and 180 cm height, 50 and 100 kg weight with normal airways, scheduled for elective surgery during general anesthesia requiring endotracheal intubation. The criteria to define a normal airway were: Mallampati classes I and II, thyromental distance >6.5 cm, interincisor distance >3 cm, ability to extend mandibular incisors anterior to maxillary incisors, ability to touch chin to chest or to extend the neck, and absence of overbite. Exclusion criteria Figure 2. VivaSight Single Lumen and the screen. included known esophageal disease, gastroesophageal reflux disease, pulmonary disease, and pregnancy. Anesthesia was induced with 2 mg/kg propofol and 2 µg/kg fentanyl. After confirming adequate mask ventilation, muscle relaxation was achieved with 0.6 mg/kg rocuronium. Patients lungs were ventilated for 3 minutes with oxygen (Fio 2 = 1), and then the reusable FT-LMA lubricated with water-soluble jelly on the posterior surface was inserted according to the manufacturer s recommendations. 11 A size 4 FT-LMA was used for patients weighing 50 to 70 kg, and a size 5 for patients weighing >70 kg. The cuff of the FT-LMA was inflated to a pressure of 60 cm H 2 O using a manometer (VBM Medizintechnik GmbH, Sulz, Germany), and the breathing circuit was connected to the FT-LMA. Adequate ventilation was assessed by proper chest expansion, bilateral auscultation of the lungs, and the presence of a CO 2 waveform on the capnograph. If adequate ventilation was not possible, the FT-LMA was removed and a second attempt was allowed. If ventilation was inadequate after the second attempt, endotracheal intubation was performed using a GlideScope (Verathon Inc., Bothell, WA) and the case excluded from the study. Figure 3. VivaSight Single Lumen inserted through the Fastrach Laryngeal Mask Airway with a normal curve. Figure 4. VivaSight Single Lumen inserted through the Fastrach Laryngeal Mask Airway with reverse curve technique. 2 anesthesia & analgesia

3 Table 1. Patients Demographic Data Age (y) 57 ± 12 Weight (kg) 80.8 ± 15 Height (cm) ± 7 Body mass index 27.4 ± 3 Sex, M:F 38/12 ASA I:II 6/44 Values are numbers or mean and SD. Once adequate ventilation was achieved, the VivaSight-SL was passed through the FT-LMA into the trachea under visual control. (Video 1, see Supplemental Digital Content 1, The VivaSight-SL size 7.5 mm was used to intubate the trachea for a size 4 FT-LMA and a size 8.0 mm for a size 5 FT-LMA. The VivaSight-SL was inserted with a concave orientation (Figs. 3 and 4) in an attempt to increase intubation success according to the technique described by Ye et al. 12 The VivaSight-SL was then advanced until the epiglottic elevator bar was pushed up and a laryngeal view was obtained. We obtained reversed images on the screen due to the orientation of the ETT. We modified Timmermann et al. s 13 criteria to score laryngeal view: grade 1: full view of the arytenoids and glottis; grade 2: epiglottis, arytenoids or glottic opening are partly visible, the structure of cords is difficult to see; grade 3: dark areas indicating an open space; and grade 4: no part of the larynx can be identified (Fig. 5). If a grade 1 view was obtained, the VivaSight-SL was passed into the trachea under direct vision and the correct position confirmed approximately 3 cm above the carina. If a grade 2 or higher was obtained, one or more of the following maneuvers were performed to obtain optimal alignment of the FT-LMA ventilation aperture with the glottis opening: (a) up-down maneuver of the FT-LMA under vision, (b) side-to-side maneuver (sagittal movement) with no change in the depth, (c) hyperextension of the head, (d) external manipulation of the larynx, or (e) injection of normal saline through the external port of the VivaSight-SL to clean the embedded video camera. If no glottic visualization was possible, these patients were then excluded and intubated using a GlideScope. Once the optimal glottic view was achieved, the second step Chandy maneuver (FT-LMA slightly lifted and moved away from the posterior oropharyngeal) was performed under vision, to improve the alignment of the ventilation orifice of the FT-LMA with the glottis. 6 The VivaSight-SL was then inserted under videoscopic observation of the trachea. A stabilizing rod was used during the removal of the FT-LMA. Two attempts to perform endotracheal intubation were allowed. All intubations were performed by 2 experienced attending anesthesiologists. The following data were recorded: the time for insertion of the FT-LMA (defined as the time from facemask removal to observing an end-tidal CO 2 curve), the time required to obtain a laryngeal view with the VivaSight-SL, number of attempts at endotracheal intubation, time to achieve endotracheal intubation (defined as the time from picking up the VivaSight-SL to observing an end-tidal CO 2 curve), and number and type of adjusting maneuvers. The patients were questioned postoperatively regarding symptoms of a sore throat, hoarseness, dysphonia, or dysphagia in the Table 2. Insertion Times for FT-LMA and VivaSight-SL Time to insert the FT-LMA (s) 15.4 ± 6 Time to achieve laryngeal view with the VivaSight-SL (s) 28.8 ± 5 Time of successful intubation with the VivaSight-SL 45 ± 7 including visualization of the carina (s) Values are numbers or mean and SD. FT-LMA = Fastrach Laryngeal Mask Airway; SL = Single Lumen. postanesthesia care unit and again 24 and 72 hours postoperatively by a blinded observer. The sample size was determined to be 42 patients, based on data from previous studies, 13,14 for a 2-sided significance level of 5%, power of 80%, and range of the first attempt success rate of 75% to 96%. Anticipating that some cases might be excluded, we chose to study 50 patients. RESULTS Patients characteristics and are presented in Table 1. The FT-LMA was placed successfully in 49 patients at the first attempt. One patient was excluded from the study after 2 failed attempts to ventilate with the FT-LMA, and his trachea was intubated with a standard ETT using a GlideScope. All 49 patients were successfully intubated with the VivaSight-SL, (95% CI, ) 47 patients at the first attempt (95% CI, ) and 2 patients at the second attempt (95% CI, ). The times to achieve an effective airway with the FT-LMA and VivaSight-SL, as well as the time required to obtain a laryngeal view with the VivaSight-SL, are described in Table 2. After introducing the VivaSight-SL through the intubating channel of the FT-LMA, a grade 1 view was obtained in 18 patients, grade 2 in 18 patients, grade 3 in 4 patients and grade 4 in 9 patients. The number and type of adjusting maneuvers are described in Table 3. Eight patients complained of sore throat after surgery in the postanesthesia care unit. Sore throat disappeared after 24 hours with the exception of 1 patient. In this patient, the sore throat disappeared after 3 days. Two patients complained of dysphonia which disappeared after 24 hours. DISCUSSION This study describes the successful use of the VivaSight-SL to intubate the trachea through the FT-LMA. The camera located on the VivaSight-SL s Table 3. Adjusting Maneuvers Adjusting maneuver Grade 2 Grade 3 Grade 4 Number of maneuvers Up-down maneuver Side-to-side maneuver Hyperextension of the 4 4 head External manipulation of the larynx Injection of saline through the external port of the VivaSight-SL to clean the embedded video camera 4 4 SL = Single Lumen. March 2013 Volume 116 Number 3 3

4 VivaSight Single Lumen Figure 5. Scoring of the laryngeal view: grade 1: full view of the arytenoids and glottis; grade 2: epiglottis, arytenoids, or glottic opening are partly visible, the structure of cords is difficult to see; grade 3: dark areas indicating an open space; grade 4: no part of the larynx can be identified. tip allowed videoscopic visualization of the laryngeal structures and enabled adjustment of the FT-LMA position to align the VivaSight-SL with the glottic opening. The first attempt endotracheal intubation rate was 47 of 50 attempts (95% CI, ), and ultimate success rate was 49 of 50 attempts (95% CI, ). To improve the first attempt success rate to intubate the trachea through the FT-LMA, various under vision techniques have been used such as fiberoptically assisted intubation and the recently withdrawn C-trach. 8,13 15 Another technique used to facilitate endotracheal intubation through the FT-LMA is the lightwand. 16 The main disadvantages of using a fiberoptic scope are its high purchase price and maintenance cost as well as its fragility. The VivaSight-SL Video 1. Insertion of the VivaSight Single Lumen (SL) into the trachea through the Fastrach Laryngeal Mask Airway (FT-LMA) under visual control. is a single use device; however, its high cost is also a disadvantage. We found a relatively low incidence (37%) of grade 1 laryngeal view. Despite the low incidence of initial proper alignment of the FT-LMA ventilation aperture with the glottic opening, a normal capnograph trace was obtained in most cases. In these cases, there is a potential risk of damaging the surrounding tissue, if intubation is performed blindly. This strengthens the importance of visual control of the anatomical structures during endotracheal intubation. The preformed polyvinyl chloride VivaSight-SL is more rigid than the dedicated silicone tracheal tube designed by Dr. Brain to be used with the FT-LMA. Thus, it is more difficult to manipulate and causes a greater angle (67 ) when emerging the ventilation aperture of the FT-LMA. By inserting the VivaSight-SL with the reversed curve technique, the emersion angle is approximately 20, similar to the reusable dedicated silicone-tipped ETT, facilitating the insertion of the ETT into the glottis. 12 Similar to other videoscopic techniques, one of the drawbacks is blurred visualization by secretions and/or blood and fogging. The irrigation channel of the VivaSight-SL helped overcome visualization problems caused by secretions. The major limitation of this study is that only patients with normal airways have been studied and the effectiveness of this technique should also be investigated in patients with difficult airways. Despite these disadvantages, the high first-attempt intubation success rate and the potential to avoid tissue trauma by blind intubation make this technique an attractive and promising concept. E 4 anesthesia & analgesia

5 DISCLOSURES Name: Luis A. Gaitini, MD. Attestation: Luis A. Gaitini has approved the final manuscript, Conflicts of Interest: Dr. Gaitini has received equipment support from VBM Medizintechnik, Mercury Medical and ET view Ltd. Name: Boris Yanovski, MD. Attestation: Boris Yanovski has approved the final manuscript, Conflicts of Interest: None. Name: Somri Mustafa, MD. Attestation: Somri Mustafa has approved the final manuscript, Conflicts of Interest: None. Name: Carin A. Hagberg, MD. Contribution: This author helped analyze the data and prepare Attestation: Carin A. Hagberg has approved the final manuscript, Conflicts of Interest: Dr. Hagberg has disclosed that she is a member of the speakers bureaus for Ambu A/S, Cook Medical, Covidien, and LMA North America. Consultant for Ambu A/S and Covidien and has received equipment support from Aircraft Medical, Ambu A/S, Clarus Medical, Cook Medical, Intersurgical, Karl Storz Endoscopy, King Systems, LMA North America, Mercury Medical, Olympus America and Verathon. Name: Pedro Charco Mora, MD. Contribution: This author helped design the study and prepare Attestation: Pedro Charco Mora has approved the final manuscript, Conflicts of Interest: Dr. Charco Mora has disclosed that he is a member of the speakers bureaus for Abbott and has received equipment support from VBM Medizintechnik, LMA North America, Karl Storz Endoscopy, Mercury Medical, Intersurgical, Verathon, Cook Medical, MSD and Prodolmed. Name: Sonia J. Vaida, MD. Contribution: This author helped design the study and prepare Attestation: Sonia J. Vaida has approved the final manuscript, Conflict of Interest: None. This manuscript was handled by: Dwayne R. Westenskow, PhD. REFERENCES 1. Gigio M, Oreste D, Oreste N. Usefulness of ETView TVT endotracheal tube for correct positioning of bronchial blockers in left lobectomy: an easy and safe combination. Minerva Anestesiol 2009;75: Barak M, Putilov V, Meretyk S, Halachmi S. ETView tracheoscopic ventilation tube for surveillance after tube position in patients undergoing percutaneous nephrolithotomy. Br J Anaesth 2010;104: Brain AI, Verghese C, Addy EV, Kapila A. The intubating laryngeal mask. I: Development of a new device for intubation of the trachea. Br J Anaesth 1997;79: Brain AI, Verghese C, Addy EV, Kapila A, Brimacombe J. The intubating laryngeal mask. II: A preliminary clinical report of a new means of intubating the trachea. Br J Anaesth 1997;79: Fukutome T, Amaha K, Nakazawa K, Kawamura T, Noguchi H. Tracheal intubation through the intubating laryngeal mask airway (LMA-Fastrach) in patients with difficult airways. Anaesth Intensive Care 1998;26: Ferson DZ, Rosenblatt WH, Johansen MJ, Osborn I, Ovassapian A. Use of the intubating LMA-Fastrach in 254 patients with difficult-to-manage airways. Anesthesiology 2001;95: Gerstein NS, Braude DA, Hung O, Sanders JC, Murphy MF. The Fastrach Intubating Laryngeal Mask Airway: an overview and update. Can J Anaesth 2010;57: Joo HS, Rose DK. The intubating laryngeal mask airway with and without fiberoptic guidance. Anesth Analg 1999;88: Chan PL, Lee TW, Lam KK, Chan WS. Intubation through intubating laryngeal mask with and without a lightwand: a randomized comparison. Anaesth Intensive Care 2001;29: Pandit JJ, MacLachlan K, Dravid RM, Popat MT. Comparison of times to achieve tracheal intubation with three techniques using the laryngeal or intubating laryngeal mask airway. Anaesthesia 2002;57: LMA North America Inc. LMA FastrachTM Reusable and LMA FastraschTM Single Use Instruction Manual. Singapore: The Laryngeal Mask Company Ltd., 2006 ed. Available at: Accessed December 10, Ye L, Liu J, Wong DT, Zhu T. Effects of tracheal tube orientation on the success of intubation through an intubating laryngeal mask airway: study in Mallampati class 3 or 4 patients. Br J Anaesth 2009;102: Timmermann A, Russo S, Graf BM. Evaluation of the CTrach an intubating LMA with integrated fibreoptic system. Br J Anaesth 2006;96: Arslan ZI, Özdamar D, Yildiz TS, Solak ZM, Toker K. Tracheal intubation in morbidly obese patients: a comparison of the Intubating Laryngeal Mask Airway and Laryngeal Mask Airway CTrach. Anaesthesia 2012;67: Brimacombe JR. Intubating LMA for airway intubation. In: Brimacombe J, ed. Laryngeal Mask Anesthesia: Principles and Practice. 2nd ed. Philadelphia, PA: Saunders, 2005: Fan KH, Hung OR, Agro F. A comparative study of tracheal intubation using an intubating laryngeal mask (Fastrach) alone or together with a lightwand (Trachlight). J Clin Anesth 2000;12:581 5 March 2013 Volume 116 Number 3 5