Response

Abstract

We appreciate Mr Haynes’ comments on the ventilation strategies targeted for ARDS specifically induced by inhaling grenade smoke. To protect from lung inflammation, improve lung mechanics and gas exchange, and prevent progression of multiple organ failure, a treatment guided by reports from the ARDS Network proposes a standard of care for ARDS.1,2 This young man, 171 cm height and 61 kg weight, had developed subcutaneous emphysema, pneumomediastinum, and bilateral pneumothorax on the third hospital day.3After bilateral tube thoracostomies, bilateral bronchopleural fistulas were diagnosed, with continuous bubbling in the water seal of the chest drainage device (see Figure), and mechanical ventilation was then applied. We have tried several ventilator modes to achieve the best oxygenation when 100% oxygen is needed.Continuous mandatory ventilation functions best with bedside observation. The initial ventilator setting was continuous mandatory ventilation and the tidal volume was 500 mL for a while, followed by pressure-support-synchronized intermittent mandatory ventilation (P-SIMV) by a respiratory therapist. Ventilatory modes were shifted among continuous mandatory ventilation, biphasic positive airway pressure, adaptive support ventilation, pressure control, and P-SIMV to maintain acceptable gas exchange. On day 16, the patient was ventilated with an Evita ventilator (Drägerwerk AG, Lübeck, Germany). The plateau pressure was depicted as airway pressure with positive end-expiratory pressure (PEEP) included, so the plateau pressure was less than 30 cm H2O in our case.For patients with bronchopleural fistula, several principles of ventilator management are essential, such as using the lowest number of mechanical breaths that permit acceptable alveolar ventilation, limiting effective tidal volume to <6–8 ml/Kg, and minimizing inspiratory time and PEEP.4The optimal ventilator strategies for patients with bilateral bronchopleural fistulas complicating ARDS have not been established. Whether the techniques for decreasing the size of the leak could affect the long-term outcome remains unknown. Independent lung ventilation via a double-lumen endotracheal tube and 2 ventilators or high-frequency jet ventilation as a treatment for bronchopleural fistula has been discouraging.For this patient with bilateral bronchopleural fistulas complicating smoke-induced ARDS, we successfully managed this critical condition with protective ventilator settings, extracorporeal life support, and corticosteroids.