Difficult double-lumen tube placement due to laryngeal web.
We present a case of difficult intubation in a patient with a
laryngeal web. A 33-year-old male patient presented for open thoracotomy
and had a previously undiagnosed laryngeal web, which complicated the
placement of a double-lumen tube. A single-lumen tube was placed with
the use of a bougie through the narrowed airway. With the subsequent use
of an airway exchange catheter, a double-lumen tube was positioned.
Techniques for managing narrowing of the supraglottic airway are
presented and the literature dealing with laryngeal webs is reviewed. In
the setting of an unusual airway and thoracic surgery, ventilation via
simpler techniques takes precedence over insertion of more complex
Key Words: laryngeal web, airway obstruction, difficult airway, double-lumen tube, intubation, tracheal, airway exchange catheter, surgery, thoracotomy
|Article Type:||Clinical report|
Anesthesia (Health aspects)
Airway obstruction (Medicine) (Risk factors)
Airway obstruction (Medicine) (Diagnosis)
Airway obstruction (Medicine) (Care and treatment)
Airway obstruction (Medicine) (Patient outcomes)
Thoracotomy (Health aspects)
|Publication:||Name: Anaesthesia and Intensive Care Publisher: Australian Society of Anaesthetists Audience: Academic Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2010 Australian Society of Anaesthetists ISSN: 0310-057X|
|Issue:||Date: Jan, 2010 Source Volume: 38 Source Issue: 1|
|Geographic:||Geographic Scope: Australia Geographic Code: 8AUST Australia|
Discovery of an undiagnosed lesion of the airway following
induction of anaesthesia is a rare and frightening event. Such lesions
can interfere with airway management and may result in significant
morbidity. We present a case of a laryngeal web that was discovered
during laryngoscopy and which complicated the placement of a
double-lumen tube (DLT).
A 33-year-old Vietnamese patient (ASA physical status III, weight 58 kg, height 166 cm) was scheduled for a thoracotomy for right upper lobectomy. He had been admitted to hospital six days earlier with haemoptysis, chest pain and dyspnoea. He had been treated for pulmonary tuberculosis many years earlier. Bronchoscopy was performed with sedation and local anaesthesia and was normal apart from right upper lobe bleeding. No abnormalities of the tracheo-bronchial tree were seen. Embolisation of blood vessels was attempted in the radiology suite, but failed.
On arrival in the operating theatre, standard monitors were applied and peripheral and central venous and arterial cannulae were placed. A 37-Fr Mallinckrodt DLT was prepared for use. Midazolam 1 mg, fentanyl 50 [micro]g and propofol 100 mg were given. Bag-mask ventilation with isoflurane in oxygen was easy and muscle relaxation was achieved with rocuronium. Laryngoscopy was performed and a grade 3 view was obtained with optimal positioning. However, a circumferential mucosal stricture was observed immediately above the larynx at the level of the supraglottic region extending superiorly into the oropharynx and DLT insertion was not attempted. There was some doubt about whether the DLT would pass through the supraglottic area. Therefore, a bougie was passed through the mucosal stricture and an 8 mm ID singlelumen tracheal tube was passed into the trachea without difficulty. No bleeding was observed and normal arterial oxygen saturation was maintained. The placement of the DLT via an exchange technique was then planned after discussion. A Cook Airway Exchange Catheter (Cook Critical Care, Bloomington, IN, USA; model C-CAE-11.0-83) was passed through the tracheal tube and it was exchanged with a DLT. Lung isolation was achieved and DLT position was optimised with fibreoptic bronchoscopy, such that the endobronchial tube cuff was visible subjacent to the carina. The thoracotomy proceeded but was complicated by bleeding and anaesthesia time was 6.5 hours. Postoperative ventilation was planned. The DLT was exchanged for an 8 mm ID singlelumen tube using the same Cook Airway Exchange Catheter. Postoperative sedation was achieved with midazolam and morphine. Attempted insertion of a nasogastric tube with the aid of a laryngoscope was unsuccessful. Packed red blood cells and fresh frozen plasma were required both intra- and postoperatively for ongoing blood loss. Tracheal extubation was achieved on the second postoperative day and the patient was discharged home on the fifth postoperative day.
The patient was referred to the Royal Perth Hospital Otolaryngology Clinic on an outpatient basis. He gave no history of trauma or previous oropharyngeal surgery and was completely asymptomatic in relation to his airway. He had normal voice quality with no reduction in oropharyngeal vocal resonance. Examination of his oropharynx revealed mucosal webbing as seen in Figure 1. This extended inferiorly to involve the supraglottic area in a circumferential manner. There was no webbing at the level of the glottis as anticipated. Given his ethnicity and absence of trauma, it was postulated that the webbing was post-inflammatory and may well have been a result of previous diphtheria infection.
Laryngeal webs may be congenital or acquired and consist of thin, transparent or thick fibrous membranes. Congenital webs, which have an incidence of approximately one in 10,000, occur as a result of incomplete re-canalisation of the primitive airway (1). They often present at birth with respiratory distress, stridor or weak cry. Less commonly, they remain asymptomatic and do not present until later life, often with a difficult intubation. Seventy-five percent of webs are located at the level of the cords and most of these lie anteriorly (2). Acquired webs may occur following trauma or inflammation of the mucosa and sub-mucosal tissues. The most common infective cause of laryngeal webs worldwide is Corynebacterium diphtheriae infection3. Symptomatic webs are treated with either surgery or laser, but asymptomatic webs are usually left untreated as the excised areas may adhere as a result of scar tissue formation (4,5).
Tubes used for lung isolation such as DLTs or Univent tubes have been described as 'difficult tubes' due to their relatively large outside diameter and an increased overall rigidity, which makes them more difficult to shape (6).
When separation of the lungs is strictly indicated, the use of DLTs cannot be avoided despite the presence of an abnormal airway. It is often claimed that a DLT can worsen the laryngoscopic view because of its greater calibre. In a patient with an unanticipated airway problem, it is often easier to initially establish a safe airway with a conventional single-lumen tube using optimised positioning, specialised laryngoscopes and other aids such as stylets or bougies. Once the airway is controlled, lung separation may be achieved with the use of a tube exchange catheter to exchange the single-lumen tube for a DLT or Univent tube. A Univent tube was not available for use in this patient. Alternatively, the single-lumen tube can remain in situ and lung separation achieved with an independent bronchial blocker. Several different tube exchange catheters are available (Cook Critical Care, Sheridan Catheter Corporation and CardioMed Supplies). They are all available in a range of external diameters, have depth markings and can be used for oxygen insufflation or jet ventilation. When passing the tube over the airway guide, a laryngoscope should be used to facilitate passage of the tube past the supraglottic structures (6).
DLTs have a number of advantages over bronchial blockers, including the ability to rapidly switch between one- and two-lung ventilation, independent bilateral suctioning and the ability to provide continuous positive airway pressure to the nonventilated lung. They are therefore the tubes of choice for one-lung ventilation in the vast majority of cases (7). As there was no bleeding from the laryngeal web following insertion of the single-lumen tube, one attempt at exchanging it for a DLT was planned. If significant bleeding had occurred, we would not have proceeded with surgery and would have sought the advice of an ear, nose and throat surgeon.
The Univent[TM] tube (Fuji Systems Corporation, Tokyo) is a single-lumen tube with an incorporated channel for the bronchial blocker. Its shape is similar to that of a standard endotracheal tube. It has been described as a useful tube for lung separation in the presence of a difficult airway (7,8). In some cases, the bronchial blocker of the Univent tube may be used as an introducer during the primary intubation8. The main advantages of the Univent tube include easier insertion than a DLT, it may be left in situ for postoperative ventilation thereby avoiding a potentially risky tube exchange, the bronchial blocker may be used to provide selective lobar blockade and the lumen of the bronchial blocker may be used to suction and provide continuous positive airway pressure to the non-ventilated lung (9). This tube is a good choice when faced with the possibility of difficult tube placement, such as our patient, or the need for rapid tube placement, such as with massive haemoptysis.
The final option is to use a single-lumen tube and proceed to use an independent bronchial blocker, thereby avoiding the use of a 'difficult tube'. A suitable independent bronchial blocker is a Fogarty Embolectomy catheter, which has occlusion balloons ranging in size from 0.5 to 3 ml (10). It may either be placed in or outside the single-lumen tube. The main disadvantage of independent bronchial blockers is the inability to ventilate and/or suction the non-ventilated lung distal to the blocker.
In conclusion, we have described the unexpected discovery of a laryngeal web in a patient scheduled for open thoracotomy. Airway management was achieved with a single-lumen tube which was then exchanged for a DLT. Alternative devices to achieve lung separation in this setting are described and their use is dependent on operator experience and preference and equipment availability. We recommend that centres in which thoracic surgery is performed maintain a range of specialised tubes, bougies and catheters to allow for management of severe haemoptysis, difficult airways and tube exchanges. As always, when planning independent lung ventilation in the setting of a difficult airway, ventilation via a simpler technique should take precedence over insertion of a complex tube.
Accepted for publication on August 31, 2009.
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(2.) Holinger PH, Brown WT. Congenital webs, cysts, laryngoceles and other anomalies of the larynx. Ann Otol Rhinol Laryngol 1967; 76:744-752.
(3.) Rupa V, Raman R. Aetiological profile of paediatric laryngeal stridor in an Indian hospital. Ann Trop Paediatr 1991; 11:137-141.
(4.) Cummings CW. Otolaryngology--Head and Neck Surgery. CV Mosby, London 1986.
(5.) Deweese DD, Saunders WH. Textbook of Otolaryngology, 6th ed. CV Mosby, London 1982.
(6.) Benumof J. Difficult tubes and difficult airways. J Cardiothorac Vasc Anesth 1998; 12:131-132.
(7.) Benumof JL, Alferey DD. Anesthesia for Thoracic Surgery. In: Miller RD, ed. Anesthesia, 5th ed. New York: Churchill Livingstone 2000. p. 1689-1690.
(8.) Garcia-Aguado R, Mateo EM, Onrubia VJ, Bolinches R. Use of the Univent System tube for difficult intubation and for achieving one-lung anaesthesia. Acta Anaesthesiol Scand 1996; 40:765-767.
(9.) Baraka A. The Univent tube can facilitate difficult intubation in a patient undergoing thoracoscopy. J Cardiothorac Vasc Anesth 1996; 10:693-694.
(10.) Benumof JL, Gaughan S, Ozaki GT. Operative lung constant positive airway pressure with the Univent bronchial blocker tube. Anesth Analg 1992; 74:406.
(11.) Ginsberg RJ. New technique for one-lung anesthesia using an endobronchial blocker. J Thorac Cardiovasc Surg 1981; 82:542-546.
Address for correspondence: Dr M. H. Schmidt, Royal Perth Hospital, Box X2213 GPO, Perth, WA 6001.
M. H. SCHMIDT *, R. H. RILEY ([dagger]), G. Y. K. HEE ([double dagger])
Department of Anaesthesia and Pain Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
* M.B., B.S. (Hons), Senior Anaesthesia Registrar.
([dagger]) M.B., B.S., F.A.N.Z.C.A., Consultant Anaesthetist.
([double dagger]) M.B., B.S., F.R.A.C.S., Consultant ENT Surgeon.
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