Utilisation de la jet ventilation en pédiatrie

Abstract

High frequency jet ventilation (HFJV) is an alternative ventilatory mode during anaesthesia for laryngeal microsurgery. This procedure ensures good visualization of the operating field but is not without risk. Thus, its use in paediatric patients requires sound knowledge of respiratory physiology of children and infants. In children up to 8 years, the jet ventilator adjustments must take into account the lower pulmonary compliance and the higher airway resistance (time-constant). In order to avoid barotrauma, which is the main HFJV complication, the jet ventilator has to include a monitoring airway pressure system. The driving pressure and the frequency must be gradually increased while checking thoracic expansion. Total intravenous anaesthesia with profound muscular relaxation using a thin transglottic catheter is the most commonly used technique. Standard monitoring of anaesthesia does not preclude strict clinical supervision so as to detect any pulmonary distension. The air-oxygen mixture must be adjusted to provide the lowest FIO 2 possible (≤ 30%) when using the CO 2 laser. The main indications for the use of HFJV in paediatric laryngeal microsurgery are laryngomalcia, laryngeal papillomatosis and subglottic haemangioma. HFJV is a reliable and useful technique in airway paediatric surgery providing the operator has good knowledge of the physiological particularities in children.