Which term describes inadequate oxygenation or ventilation requiring assistance?

• A. Dyspnea
• B. Tachypnea
• C. Respiratory Failure
• D. Orthopnea

Answer: (C)

Respiratory failure is when the lungs can no longer maintain adequate gas exchange on their own, so the body needs help to oxygenate the blood or remove carbon dioxide. This means either low arterial oxygen (hypoxemia), high arterial carbon dioxide (hypercapnia), or both, and it typically requires medical interventions such as supplemental oxygen, noninvasive ventilation, or advanced airway/ventilatory support.

Other terms describe symptoms or patterns rather than the need for ventilatory assistance. Dyspnea is the subjective sensation of breathlessness and can occur in many conditions without implying that life-sustaining support is needed. Tachypnea is rapid breathing, an observation that can accompany many respiratory or metabolic problems but doesn’t by itself indicate failure to exchange gases. Orthopnea is difficulty breathing when lying flat, often related to heart failure or fluid redistribution, and does not by itself define an inability of the lungs to oxygenate or ventilate.