At first glance, it may appear that Michael is not adherent with his prescribed treatment plan. If he were taking his medication correctly, he would not be readmitting so frequently. He claims that he uses his inhaler daily, as prescribed, but continues to experience severe dyspnea.
A closer look would reveal that Michael had both knees replaced, making whole-body exercise nearly impossible. This lack of exercise has compromised his skeletal muscles and has led to further respiratory muscle wasting and deconditioning. Additionally, lung hyperinflation and hypoxemia has compromised his respiratory muscle strength. Due to respiratory muscle weakening, he no longer has the breath strength to effectively take his inhaled medication. His suboptimal peak inspiratory flow inhibits sufficient drug delivery. This results in costly readmissions for Michael’s care network and reduced quality of life for him.
Adequate peak inspiratory flow is required for patients to successfully inhale powder from a dry-powder inhaler (DPI) into the lungs. Some patients with severe COPD cannot achieve adequate inspiratory force to break up drug particles sufficiently enough to reach the lower respiratory tract to have clinical benefit.