|Year : 2013 | Volume
| Issue : 1 | Page : 82-83
Incidental laryngeal web simulating intra-operative refractory bronchospasm
Preet Mohinder Singh, Puneet Khanna
Department of Anaesthesia, All India Institute of Medical Sciences, Delhi, India
|Date of Web Publication||14-Mar-2013|
Preet Mohinder Singh
Department of Anaesthesia, All India Institute of Medical Sciences, Delhi
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Singh PM, Khanna P. Incidental laryngeal web simulating intra-operative refractory bronchospasm. Indian J Anaesth 2013;57:82-3
| Introduction|| |
Incidental asymptomatic laryngeal webs have always puzzled anesthesiologists with varied presentations and are identified on direct laryngoscopy done after induction of anaesthesia. , Situations where laryngeal mask airway (LMA) is used it may still remain obscured to cause implications intraoperatively.
| Case Report|| |
We present a case of 17 years; 45 kg ASA I female operated for posttraumatic lid injury repair under general anaesthesia. Her medical history and investigations were unremarkable. Anaesthesia was induced with intravenous fentanyl (90 μgms) and propofol (90 mgs). Mask ventilation was possible but with slight decrease in chest compliance. Vecuronium was given on finding no auscultatory abnormality with possibility to improve the compliance and to proceed to LMA insertion. A size three proseal LMA was inserted and its optimal position was confirmed by tapping the suprasternal notch and observing simultaneous movement of a column of lubricant jelly (Brimacombe bounce test)  as well as by ability to pass suction catheter via the orogastric channel without any resistance. The patient was put on pressure control ventilation and during the surgery inspiratory pressure had to be continuously stepped up from initial of 14 to 24 cm H 2 O, still attained tidal volume remained suboptimal. However we managed to maintain ETCO 2 of around 45 mmHg by increasing ventilator frequency. The ETCO 2 graph showed configuration like a bronchospasm. On auscultation, wheeze like added sounds could be heard. Considering it to be bronchospasm salbutamol and ipratropium puffs along with intravenous hydrocortisone were given. The surgery lasted for 20 minutes during which patient received salbutamol twice but the bronchospasm and capnograph abnormality persisted. At the end of surgery on reversing the neuromuscular blockade the patient showed transient chest in drawing, which resolved on complete recovery of neuromuscular tone. On removing the LMA, no wheeze could be auscultated; hence check laryngoscopy was done to rule out any possibility of upper airway obstruction and a laryngeal web covering more than half the glottis was discovered [Figure 1].
| Discussion|| |
Laryngeal webs are rare with reported incidence 1 in 10000,  they present with stridor in childhood  however, can be discovered in asymptomatic adults under anaesthesia and are associated with failed intubations.  Varied presentations under anaesthesia range from failed intubation to post-operative obstruction requiring emergency tracheostomy.  Our patient had no previous history of any respiratory obstruction even in childhood and thus suspicion of laryngeal web was extremely low. Interestingly when the LMA position is confirmed to be optimal to achieve adequate tidal volume it would be normal tendency to raise the inspiratory pressure. Increasing this pressure with an LMA can induce a leak in the circuit, which can cause change in configuration of ETCO 2 curve and also cause the leak sound can be falsely perceived as a possible wheeze as in our case. The differentiation of added sounds becomes even more difficult when respiratory rate is raised, as was done up to 24/minute in our case. We could only conclude to a presence of laryngeal web when a laryngoscopy was done.
| Conclusion|| |
We wish to highlight that possibility of laryngeal web as a diagnosis in asymptomatic patients should be considered when larynx is not directly visualized and a possible bronchospasm is suspected not fitting into classical clinical picture.
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