A nurse is caring for a patient with sleep apnea. Which types of ventilator support should the nurse ...

ANS: C, D
Ventilatory support is achieved using a variety of modes, including continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BiPAP). The purpose of CPAP and BiPAP is to maintain a positive airway pressure and improve alveolar ventilation. This prevents or treats atelectasis by inflating the alveoli, reducing pulmonary edema by forcing fluid out of the lungs back into circulation, and improving oxygenation in those with sleep apnea. AC, PSV, and SIMV are invasive mechanical ventilation and are not routinely used on patients with sleep apnea. AC delivers a set tidal volume (VT) with each breath, regardless of whether the breath was triggered by the patient or the ventilator. Synchronized intermittent mandatory ventilation like AC delivers a minimum number of fully assisted breaths per minute that are synchronized with the patient's respiratory effort. Any breaths taken between volume-cycled breaths are not assisted; the volume of these breaths is determined by the patient's strength, effort, and lung mechanics. PSV mode is often combined with SIMV mode: inspiratory pressure is added to spontaneous breaths to overcome the resistance of the endotracheal tube or to help increase the volume of the patient's spontaneous breaths.