[Graphic evaluation of the significance band for hypercapnia in pulmonary disorders]

Alveolar hypoventilation due to the chronic obstruction of the airway such as pulmonary emphysema, or severe restrictive dysfunction due to sequela of pulmonary tuberculosis causes chronic hypercapnia (chronic respiratory acidosis). Ninety-five percentile of significance band of chronic and acute hypercapnia of both experimental and clinical setting is introduced in the graphic display of the acid-base balance. On acute exacerbation of these disorders, examination of arterial blood gas in series are usually plotted along the significance band of hypercapnia. With clinical improvement, the plot will gradually drop down to the chronic stable area of the band. Although cases with metabolic disorders complicate the interpretation, evaluation of the acid-base status using the graphic display will be of help at bedside assessment.