Ventilator management in critical illness

Respiratory failure remains one of the leading causes of maternal mortality. This chapter reviews the general principles of ventilator management in the gravid patient with respiratory failure. It elaborates early identification and management of respiratory compromise with the most recent advances in mechanical support. The chapter discusses ventilator modes such as controlled mechanical ventilation (CMV), synchronized intermittent mandatory ventilation (SIMV), pressure support ventilation (PSV), and pressure-regulated volume control (PRVC) modes. Concerns about maternal hypercapnia on the developing fetus are discussed. Modern ventilatory management includes a strategy of small tidal volumes with adequate levels of positive end expiratory pressure (PEEP). Most evidence recommends that in between spontaneous breathing trials, the patient should receive comfortable stable ventilatory support in order to avoid muscle fatigue. Factors that cause an increase in ventilatory requirements include increased CO²production, increased dead space ventilation, and an inappropriately elevated respiratory drive.