The laryngeal tube (known as the King LT in the U.S.) is an airway management device designed as an alternative to other airway management techniques such as mask ventilation, laryngeal mask airway, and tracheal intubation. This device can be inserted blindly through the oropharynx into the hypopharynx to create an airway during anesthesia and cardiopulmonary resuscitation so as to enable mechanical ventilation of the lungs.
History and development
The laryngeal tube was developed in Germany and introduced to the European market by VBM Medizintechnik in the autumn of 1999. Since then the design has been modified several times. Currently four different models are used: the standard tube as single use or re-use models and the modified tube (laryngeal tube-Suction II) as single use or re-use models. The re-usable models can be autoclaved up to 50 times, while the modified laryngeal tube (Suction) incorporates an extra lumen for inserting a gastric tube or suction system. There are six sizes of the laryngeal tube, ranging from newborn (size 0) to large adult (size 5). The connector of the tube is color-coded for each size. The different sizes are calibrated according to weight or height.
The laryngeal tube was licensed for use during cardiopulmonary resuscitation in Japan in 2002, and approved for use in the United States by the Food and Drug Administration in 2003. The European Resuscitation Council, in its 2005 guidelines for advanced life support (ALS), accepts its use as an alternate airway device for medical personnel who are not experienced in tracheal intubation.
In its basic (standard) version, the laryngeal tube is made up of a tube with a larger balloon cuff in the middle (oropharyngeal cuff) and a smaller balloon cuff at the end (oesophageal cuff). The tube is kinked at an angle of 30-45° in the middle; the kink is located in the larger cuff. There are two apertures, located between the two cuffs, through which ventilation takes place. Both cuffs are inflated through a single small lumen line and pilot balloon. The cuffs are high-volume, low-pressure cuffs with inflating volume ranging from 10 ml (size 0) to 90 ml (size 5). A large bore syringe, which is marked with the required volume for each size, is used to inflate the cuffs. A cuff inflator can also be used, in which case the cuffs should be inflated to a pressure of 60 cm H2O. Three black lines on the tube indicate the depth of insertion when aligned with the teeth.
Use and efficacy
Various studies have shown that insertion and use of the standard tracheal tube is easy, providing a clear airway in the majority of cases. Comparative studies indicate that the standard laryngeal tube is generally as effective as the laryngeal mask airway, while some studies indicate that the Pro-seal laryngeal mask may be more effective than the standard laryngeal tube under controlled ventilation conditions in general anesthesia. The indications and contraindications for use of the laryngeal tube are similar to those of the laryngeal mask airway and include the use in general anesthesia for minor surgical operations. Several studies describe the usefulness of the device in securing a difficult airway, even in cases where insertion of the laryngeal mask had failed. The double-lumen laryngeal tube-Suction II, with the possibility of placing a gastric tube, has been found to have distinct advantages over the standard laryngeal tube and has been recommended as a first-line device to secure the airway in emergency situations when direct laryngoscopy fails in neonates and infants. The laryngeal tube is also recommended for medical personnel not experienced in tracheal intubation, and as a rescue device when intubation has failed in adults.
- CME Module 10: Recent Developments in Supraglottic Airway Devices, University of Toronto, Department of Anesthesia Website retrieved 21 May 2013
- Asai, T; Shingu, K (2005 Dec). "The laryngeal tube.". British journal of anaesthesia 95 (6): 729–36. doi:10.1093/bja/aei269. PMID 16286348.
- Genzwuerker, H.V.; Dhonau, S; Ellinger, K (31 January 2002). "Use of the laryngeal tube for out-of-hospital resuscitation". Resuscitation 52 (2): 221–224. doi:10.1016/S0300-9572(01)00472-5. PMID 11841891.
- Russi, Christopher S.; Wilcox, Cari L.; House, Hans R. (28 February 2007). "The laryngeal tube device: a simple and timely adjunct to airway management". The American Journal of Emergency Medicine 25 (3): 263–267. doi:10.1016/j.ajem.2006.03.018. PMID 17349898.
- Wiese, C.H.R.; Semmel, T.; Müller, J.U.; Bahr, J.; Ocker, H.; Graf, B.M. (31 January 2009). "The use of the laryngeal tube disposable (LT-D) by paramedics during out-of-hospital resuscitation—An observational study concerning ERC guidelines 2005". Resuscitation 80 (2): 194–198. doi:10.1016/j.resuscitation.2008.08.023. PMID 19010582.
- Sunde, Geir Arne; Brattebø, Guttorm; Ødegården, Terje; Kjernlie, Dag Frode; Rødne, Emma; Heltne, Jon-Kenneth (1 October 2012). "Laryngeal tube in 347 out-of-hospital cardiac arrest patients - an acceptable airway tool, but not the final answer?". Resuscitation 83: e15. doi:10.1016/j.resuscitation.2012.08.039.
- Asai, T.; Murao, K.; Shingu, K. (1 November 2000). "Efficacy of the laryngeal tube during intermittent positive-pressure ventilation". Anaesthesia 55 (11): 1099–1102. doi:10.1046/j.1365-2044.2000.01710.x. PMID 11069337.
- Asai, T.; Shingu, K.; Cook, T. (1 August 2003). "Use of the laryngeal tube in 100 patients". Acta Anaesthesiologica Scandinavica 47 (7): 828–832. doi:10.1034/j.1399-6576.2003.00183.x. PMID 12859303.
- Doerges, Volker; Ocker, Hartmut; Wenzel, Volker; Schmucker, Peter (1 May 2000). "The Laryngeal Tube: A New Simple Airway Device". Anesthesia & Analgesia 90 (5): 1220–1222. doi:10.1097/00000539-200005000-00042.
- Asai, T.; Kawashima, A.; Hidaka, I.; Kawachi, S. (1 November 2002). "The laryngeal tube compared with the laryngeal mask: insertion, gas leak pressure and gastric insufflation". British Journal of Anaesthesia 89 (5): 729–732. doi:10.1093/bja/89.5.729. PMID 12393771.
- Cook, T. M. (1 September 2003). "Randomized comparison of laryngeal tube with classic laryngeal mask airway for anaesthesia with controlled ventilation". British Journal of Anaesthesia 91 (3): 373–378. doi:10.1093/bja/aeg192. PMID 12925477.
- Ocker, H; Wenzel, V; Schmucker, P; Steinfath, M; Dörges, V (2002 Oct). "A comparison of the laryngeal tube with the laryngeal mask airway during routine surgical procedures.". Anesthesia and analgesia 95 (4): 1094–7, table of contents. PMID 12351302.
- Wrobel, M; Grundmann, U; Wilhelm, W; Wagner, S; Larsen, R (2004 Aug). "[Laryngeal tube versus laryngeal mask airway in anaesthetised non-paralysed patients. A comparison of handling and postoperative morbidity]. (German)". Der Anaesthesist 53 (8): 702–8. PMID 15167948.
- Brimacombe, Joseph; Keller, Christian; Brimacombe, Lawrence (1 September 2002). "A Comparison of the Laryngeal Mask Airway ProSeal™ and the Laryngeal Tube Airway in Paralyzed Anesthetized Adult Patients Undergoing Pressure-Controlled Ventilation". Anesthesia & Analgesia 95 (3): 770–776. doi:10.1213/00000539-200209000-00045. PMID 12198070.
- Cook, T. M. (1 November 2003). "Randomized crossover comparison of the ProSealTM laryngeal mask airway with the Laryngeal Tube(R) during anaesthesia with controlled ventilation". British Journal of Anaesthesia 91 (5): 678–683. doi:10.1093/bja/aeg239. PMID 14570790.
- Matioc, Adrian A.; Olson, John (1 December 2004). "Use of the Laryngeal Tube™ in two unexpected difficult airway situations: lingual tonsillar hyperplasia and morbid obesity". Canadian Journal of Anesthesia/Journal canadien d'anesthésie 51 (10): 1018–1021. doi:10.1007/BF03018491. PMID 15574554.
- Asai, T.; Matsumoto, S.; Shingu, K.; Noguchi, T; Koga, K. (1 August 2005). "Use of the laryngeal tube after failed insertion of a laryngeal mask airway". Anaesthesia 60 (8): 825–826. doi:10.1111/j.1365-2044.2005.04312.x. PMID 16029243.
- Scheller, Bertram; Schalk, Richard; Byhahn, Christian; Peter, Norman; L’Allemand, Nanette; Kessler, Paul; Meininger, Dirk (30 June 2009). "Laryngeal tube suction II for difficult airway management in neonates and small infants". Resuscitation 80 (7): 805–810. doi:10.1016/j.resuscitation.2009.03.029. PMID 19410354.
- Schalk, Richard; Byhahn, Christian; Fausel, Felix; Egner, Andreas; Oberndörfer, Dieter; Walcher, Felix; Latasch, Leo (28 February 2010). "Out-of-hospital airway management by paramedics and emergency physicians using laryngeal tubes". Resuscitation 81 (3): 323–326. doi:10.1016/j.resuscitation.2009.11.007. PMID 20006418.