Optimization of Inhalation Therapy Considering Peak Inspiratory Flow in Patients with Exacerbation of Chronic Obstructive Pulmonary Disease in Real Clinical Practice

Aim: To determine the values of peak inspiratory flow (PIP) for choosing an inhaler in patients with exacerbation of chronic obstructive pulmonary disease (COPD) and to evaluate the possibility of optimizing inhalation therapy considering PIP in real clinical practice. Design: Open cohort controlled prospective study. Materials and methods. 76 people were examined. Group 1 included 32 patients with COPD exacerbation, 18 of them were re-examined before discharge and completed a survey 3 months after discharge from the hospital. Group 2 consisted of 15 patients with stable COPD. Group 3 included 29 healthy individuals. PIF using various inhalers was studied using the In-Check DIALTM G16 Clement Clarke International Limited (Great Britain), fixing the level without resistance (R0) and 5 levels of resistance (R1–R5). Suboptimal PIF (sPIF) values were considered at R0 < 90, R1–R4 < 60, R5 < 30 l/min. Spirometry was performed on a Flowscreen II spirometer (Jaeger) with a flow-volume curve recording, calculation of generally accepted indicators, and on a PTS-14P-01 pressure-tachospirograph to determine the peak inspiratory rate. Statistical data processing was carried out using the Statistica v. 10. According to the Bonferroni principle, differences were considered significant at p < 0.005. Results. During exacerbation of COPD, a decrease in PIF from 120 to 40 l/min (p < 0.001 compared with the control) and the presence of sPIF in 5–75% of cases, depending on the type of inhalation device, were revealed (no sPIF was noted in the control). Most patients were free to use a nebulizer, a metered-dose aerosol inhaler (MAI), a liquid inhaler (Respimat) and a breathhaler upon admission to the hospital. Patients could not create the necessary inspiratory effort when using the ellipt in 47% of cases, turbuhaler — in 63%, nexthaler — in 75%, handihaler — in 31%. With proven positive clinical and functional dynamics during treatment (increase in FEV1 from 37% (28; 53) to 55% (37; 62), p < 0.004), the identified changes persisted by the time of discharge from the hospital and did not reach the values of PIF and sPIF, determined in stable COPD. Analysis of PIF and sPIF in patients in real clinical practice, depending on the drugs received, showed that by the time they were discharged from the hospital, half of the patients had sPIF, continued to use turbuhaler and handihaler inhalers, and were not able to create an adequate PIF for effective inhalation of drugs. A survey of patients 3 months after discharge from the hospital showed that patients with optimal PIF values, who used drugs with the help of PPI, Respimat and Breezhaler, did not have exacerbations within the indicated periods. Patients with CPIP who continued to use the combination of turbuhaler and handihaler had moderate exacerbations. Conclusion. Optimization of inhalation therapy based on PIP in patients with COPD exacerbation should include: 1) the possibility of choosing the optimal inhaler, considering the direct determination of PIF; 2) replacement of a high-resistance powder inhaler with a PDI/Respimat or a low-resistance powder inhaler (breather, ellipta); 3) education of COPD patients in the correct technique of inhalation. PIF testing in COPD exacerbations may help clinicians identify patients at higher risk of readmission and personalize powder inhaler selection. Keywords: chronic obstructive pulmonary disease, peak inspiratory flow, inhalation therapy, inhaler resistance.