Compare Airway Pressure Release Ventilation (APRV) to Conventional Mechanical Ventila

Inclusion Criteria: * Participants must have histologically or cytologically confirmed gynecological or genitourinary cancer. * Subjects will have the physiologic reserve to undergo a robotic-assisted gynecological or genitourinary surgical procedure that uses anesthesia via Airway Pressure Release Ventilation and via Conventional Mechanical Ventilation. * Adults (≥18 years old) * ECOG performance status ≤ 2. * Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: * Vulnerable subjects will not be enrolled for this study. * Patients who have COPD and are on oxygen at home or who have COPD requiring routine daily inhalers or daytime oxygen are excluded. * Patients who have history of major lung resection are excluded. * Patients with body mass index (BMI) \>50 are excluded. * Patients with pulmonary infection within the past 2 months of screening are excluded. * The availability of oxygen to a fetus during this experimental procedure has not been established. Therefore, patients known to be pregnant per operating room (OR) policy will be excluded.