Stage IV emphysema is an indication of the severity of emphysema according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) emphysema staging system, as reported by WebMD. Stage IV emphysema describes a very severe case, although it's important to note that any one individual's outcome cannot be accurately predicted by emphysema staging systems.Continue Reading
The staging system features a the major factor of forced expiratory volume, or FEV1, which measures what amount of air the patient can exhale forcefully in 1 second. The GOLD system's four stages are Stage I, where the emphysema is mild and FEV1 is at 80 percent of normal or greater, Stage II, where the emphysema is moderate and FEV1 is at 50 percent or greater by less than 80 percent of normal, Stage III, where the emphysema is severe and the FEV1 is at 30 percent or greater but less than 50 percent of normal, and Stage IV, where the emphysema is very severe and the FEV1 is at less than 30 percent of normal, or less than 50 percent of normal with low blood oxygen levels.
Although very widely used and well-established, the GOLD system does not take into account other important factors in the patient's life. Another system, the BODE emphysema staging system, takes into account body mass index, airflow limitation, breathlessness and exercise capacity, and does slightly better at determining a prognosis than GOLD does.Learn more about Conditions & Diseases