In this article, we will discuss the Role of Mechanical Ventilation (assisted ventilatory support) in the Management of ARDS. So, let’s get started.
Mechanical Ventilation (assisted ventilatory support)
In ARDS (acute respiratory distress syndrome), adequate oxygenation is usually not achieved with less invasive measures. Mechanical ventilator support after endotracheal intubation is initially started with volume cycled mechanical ventilators with low tidal volumes. To begin with, the initial ventilator setting could be FiO2 as 1.0 (or lower value that can achieve a PaO2 to >60 mm Hg and oxygen saturation >90%), low tidal volume 6 ml/kg body weight, PEEP less than or equal to 5 cm of water and expiratory flow 760 L/min. High PEEP may be applied to increase the lung volume and keep the alveoli open. PEEP is applied in small increments of 3-5 cm H2O up to a maximum of 15 cm H2O to achieve maximum oxygen saturation of >90% with low non-toxic FiO2 levels (<0.6). Ventilatory rate of 20-25 breaths/minute is needed to keep PaCO2 and pH normal. A multicentric trial has shown low mortality rates when low tidal volumes were used.
Airway pressure release ventilation inverse ratio ventilation and high frequency ventilation are other newer methods of ventilation to improve oxygenation.
Other ventilatory strategies: High frequency ventilation or partial liquid ventilation and lung replacement therapy with extracorporal membrane oxygenation has yield promising results in selected patients.