ANCC Medical-Surgical Nursing Exam Prep

Answer - C - If medication used to relax and dilate bronchioles is effective, effective gas exchange will be manifested by an improved PEFR because air will be able to freely enter and leave the lungs and normal gas exchange will take place. Peak expiratory flow rate refers to the amount of air inspired. If the PEFR is below the amount of air inspired, it means that air is trapped in the alveoli and bronchioles because of bronchial spasms and blockage by accumulated secretions, this prevents proper exchange of oxygen and carbon dioxide and leads to hypoxia and acidosis.