Acute respiratory failure in the oncologic critical care population: Mechanisms, diagnosis, and evolving therapeutic strategies.

Cancer is the second leading cause of death and a significant global burden. Up to 5% of patients with malignancies develop critical illnesses requiring advance support in intensive care units (ICU) accounting for approximately 15%-20% of all admissions. Acute respiratory failure (ARF), the main cause of ICU admission, most often manifests as hypoxemia due to ventilation-perfusion mismatch, shunt physiology, and impaired alveolar-capillary gas transfer, although hypercapnia may occur when airway obstruction, respiratory muscle weakness, or central ventilatory drive impairment predominates. These commonly coexist and are driven by the combined effects of tumor burden, treatment-related lung injury, infection, and reduced host reserve, leading to complex and evolving patterns of respiratory failure. Despite the improvement in access, earlier interventions, and better medical care overall, it is still associated with higher mortality than in non-cancer patients. In this review, we briefly discuss the current understanding of ARF in cancer patients.