The critically ill obstetric patient with acute respiratory failure may require mechanical ventilation and at times presents a clinical challenge to the intensivist. The most appropriate strategy for an individual patient should be determined on clinical grounds, available expertise, and local resources.

As in the non-pregnant patient, the goals of mechanical ventilation are to provide sufficient gas exchange while avoiding lung injury. Lung protective ventilatory strategies employed for non-pregnant patients are appropriate in the obstetric population. However, the physiological changes of pregnancy may influence ventilatory strategy. Maternal oxygenation should be optimised and oxygen saturation maintained above 95% to ensure foetal well-being. Lower oxygen saturation limits that are acceptable in other patients are not advisable in obstetric patients. Likewise, permissive hypercapnia in the pregnant patient should generally be avoided to minimise the risk of foetal acidosis. Chest radiographs should only be performed as necessary in the obstetric patient.

Delivery of the foetus in the patient with severe respiratory compromise requiring mechanical ventilation may improve lung mechanics and ventilation settings but there are no studies to guide on the timing of delivery. Foetal monitoring should always be performed in the presence of a viable foetus. Each case should be considered individually along with maternal and foetal concerns in the decision-making process.

Applying the ethical principles of beneficence, non-maleficence, autonomy, and justice become more complex in the ventilated pregnant patient in situations such as medical futility in the mother or life support therapy after brain death. A multidisciplinary management approach is necessary, as in other complex decision-making situations in an obstetric patient.