DIAGNOSTIC BRONCHOSCOPY FOR EVALUATION OF CONGENITAL STRIDOR:A CASE SERIES

Introduction: Stridor is a noise mechanically produced through partially occluded airway. Airway obstruction may be extrathoracic or intrathoracic. Stridor may be congenital or acquired. Timing in respiratory cycle determines anatomic location of lesion – inspiratory, biphasic, or expiratory. Gold standard for diagnosis is bronchoscopy which requires general anaesthesia in infants and small children. Major anaesthetic concerns are – possible difficult airway, sharing of an already compromised airway, airway oedema.

Case Description: 40 infants, 0 - 6 months age, with history of noisy breathing suggestive of congenital stridor, planned for diagnostic rigid bronchoscopy with or without therapeutic procedure, over one year period. Preoperative treatment – humidified oxygen, nebulization, dexamethasone, antibiotics, anti-reflux medication. Not premedicated, standard monitors applied. Induction of anaesthesia with inhalational oxygen and sevoflurane or intravenous propofol, fentanyl 1 mcg/kg, dexamethasone 0.5 mg/kg. Topical lidocaine 2% sprayed at vocal cords. 100% oxygen with propofol infusion for maintenance with spontaneous ventilation via nasopharyngeal airway. Patients requiring surgical intervention intubated using microcuffed endotracheal tube. Patients observed post-operatively. If ventilation was inadequate, intubated to control airway during recovery, extubated on restoration of spontaneous ventilation. After surgical intervention, babies shifted to ICU for elective ventilation for 48 hours.

Discussion: On bronchoscopy, laryngomalacia was the finding in majority of cases. Others had subglottic stenosis, tracheomalacia, vocal-cord paresis, laryngeal cyst. Out of 40 patients, 9 underwent therapeutic procedure and were electively ventilated, 26 resumed spontaneous breathing, 2 patients had delayed recovery and 2 had severe chest retractions and desaturations and they were managed accordingly. One baby aged 6 months diagnosed with grade III subglottic stenosis desaturatedand tracheostomy had to be done. Conclusion:Anaesthesia for rigid diagnostic bronchoscopy is a significant challenge. Rigid bronchoscopy under general anaesthesia requires multidisciplinary approach and close cooperation between all team members.