Choking on solid objects is a leading cause of morbidity and mortality in children under 3 years of age.1 Efforts to decrease the incidence of foreign body aspiration in children include the recent recommendation by the American Academy of Pediatrics that the traditional shape of the hot-dog should be redesigned.2 Despite such preventive measures, bronchoscopic foreign body retrieval will always be with us.
Anaesthesia for bronchoscopic foreign body retrieval is a controversial subject. Few anaesthesiologists agree on the best method of providing general anaesthesia and the best mode of ventilation.3 There is good reason for this as little or no evidence exists with which to guide anaesthetic management.4,5 In this edition of European Journal of Anaesthesiology, Dr Liao et al.6 report a prospective study performed to determine differences in outcomes between sevoflurane and total intravenous anaesthesia (TIVA) with propofol-remifentanil. Their major finding was that the sevoflurane group had better intraoperative haemodynamic stability.
The study by Liao et al., however, covers only one aspect of anaesthetic management for these procedures. In their practice, spontaneous ventilation represents the ‘standard of care’ for bronchoscopic retrieval. Advantages of spontaneous ventilation include the ability to provide continuous ventilation despite interruptions in the anaesthesia breathing circuit, and in the case of obstructive lesions, negative-pressure breathing may provide better oxygenation and ventilation. But there are also inherent disadvantages with this method, including the requirement to ensure that the depth of anaesthesia is sufficient to suppress airway reflexes and prevent patient movement during instrumentation, yet maintaining adequate ventilatory function and haemodynamic stability. Thus, topical anaesthesia to the airway is an important component of this technique. When using a primarily spontaneous ventilation technique, the use of occasional assisted or controlled ventilation during episodes of hypoventilation or hypoxaemia is inevitable.
An alternative point of view supports the administration of a neuromuscular blocker with controlled ventilation for bronchoscopy. Full muscle relaxation ensures immobility during the most stimulating parts of the procedure. Of necessity, this creates a reliance on intermittent positive-pressure breaths between apnoeic periods or via the ventilating port of the bronchoscope. The use of optical forceps with a ventilating port can help by decreasing the amount of time spent apnoeic. General anaesthesia can be provided by a TIVA technique, which avoids the effects of interruption of volatile anaesthesia and should reduce recall. It also decreases operating room pollution from escaping inhalational gases. In the case of a foreign body lodged deep within the bronchial tree, a theoretical disadvantage of positive-pressure ventilation is the unintentional movement of the object to a more distal part of the airway, causing obstruction. However, this complication is extremely rare.7
Individual anaesthesiologists may have their own ideas as to the best clinical technique for paediatric bronchoscopy, but the fact remains that there is no scientific evidence to indicate that one mode of ventilation is any safer than another. The prospective study by Liao et al. is an excellent beginning to research in a field largely neglected until recently. Further studies should assess the relative safety of controlled vs. spontaneous ventilation, and once that answer is known, additional points of technique should be tested, including eventually, postoperative recovery indices. Children will never stop requiring anaesthesia for bronchoscopic foreign body, so it is incumbent upon us to determine the best way to keep them from further harm.
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2 Committee on Injury VaPP. Prevention of choking among children. Pediatrics
3 Zur KB, Litman RS. Pediatric airway foreign body retrieval: surgical and anesthetic perspectives. Paediatr Anaesth 2009; 19(Suppl 1):109–117.
4 Farrell PT. Rigid bronchoscopy for foreign body removal: anaesthesia and ventilation. Paediatr Anaesth 2004; 14:84–89.
5 Litman RS, Ponnuri J, Trogan I. Anesthesia for tracheal or bronchial foreign body removal in children: an analysis of ninety-four cases. Anesth Analg 2000; 91:1389–1391.
6 Liao R, Yi Li J, Yue Liu G. Comparison of sevoflurane volatile induction/maintenance anaesthesia and propofol-remifentanil total intravenous anaesthesia for rigid bronchoscopy under spontaneous breathing for tracheal/bronchial foreign body removal in children. Eur J Anaesth
7 Dudley JP. Bilateral pneumothorax resulting from the bronchoscopic removal of a puncture vine fruit. Ann Otol Rhinol Laryngol 1983; 92:396–397.