Investigators improved iloprost administration in a patient with pulmonary arterial hypertension (PAH) and severe dyspnea and hypoxemia by optimizing oxygen delivery, according to a case study published in Pulmonary Circulation.
Although inhaled iloprost improves pulmonary hemodynamics, exercise capacity, and quality of life in patients with PAH, the medication must be inhaled between 6 and 9 times per day. In patients suffering from severe dyspnea this can be difficult, particularly because prolonged duration of inhalation is often required, as these patients can only take shallow breaths.
Kazuhiko Nakayama, MD, PhD, from the Division of Cardiovascular Medicine, Department of Internal Medicine at Kobe University Graduate School of Medicine in Japan, and colleagues reported on the case of a 75-year-old former smoker with a 48-year-smoking history, chronic obstructive pulmonary disease, and idiopathic PAH. Although iloprost therapy was effective in this patient, his severe dyspnea resulted in prolonged duration of iloprost administration, and he was often unable to complete inhalation of the drug.
The investigators modified the inhalation technique by attaching a nasal cannula to the inlet port of the inhalator, shortening the duration of iloprost administration from 9.0 to 3.3 minutes. This ultimately resulted in an increase in iloprost delivery from 2.5 to 5 µg. As a result, the patient’s World Health Organization’s functional classification of PAH improved from IV to III, and the 6-minute walk distance increased from 90 to 240 m.
After the patient was discharged from the hospital, he found that he occasionally required an inhalation duration of more than 10 minutes. By sealing the inlet port using a rubber ampoule cutter, and thus increasing inspiratory resistance, he reduced that time from 8.3 to 3.3 minutes.
The authors noted that they applied this optimization technique on 3 more patients with PAH. Although the method worked well on two of these patients, it was not effective in the third patient. They called for more case studies using this technique and reported that they observed a dramatic improvement in pulmonary hemodynamics with effective iloprost administration.
Disclosures: Several authors report financial relationships with Acetelion Pharmaceutical Japan, Bayer Pharma AG, and GlaxoSmithKline.
Nakayama K, Emoto N, Tamada N, et al. The optimization of iloprost inhalation under moderate flow of oxygen therapy in severe pulmonary arterial hypertension [published online May 21, 2018]. Pulm Circ. doi:10.1177/2045894018781537