No abstract

Nebulised therapy for pulmonary disease has been applied for a long time. However, the total particle deposition depends on many factors that are difficult to control and varies between 20 and 95 %. We here report on a new method to facilitate the pressure supported nasal long-term inhalation (NLI).Our study included 10 patients (f=5, m=5), age range 49 to 75 years, presenting several COPD stages (GOLD I-III). The NLI device generated particle sizes from 1-2 µm. The pressure support was adjusted to 10 mbar. We examined the efficacy of the method by screening the deposition in nasal and thoracic airways. We used 99mTc-nanocoll to identify the activity scintigraphically in various respiratory sections.We could show that deposition in the lung periphery by using the pressure supported transnasal application will increase significantly compared with conventional methods. The usual method produced an average nasal deposition of 5.9 MBq and a periphery deposition of 9.6 MBq, whereas NLI method results in an average nasal deposition of 4.2 MBq and a periphery deposition of 12.9 MBq, respectively.Our study showed that it was possible to penetrate even in periphery pulmonary tissue in COPD patients by using the NLI system. In addition, we achieved an enhancement of the thoracic deposition of 99mTc-nanocoll, when recorded a reduction of activity in the nasopharyngeal zone. Further clinical trials will be necessary to define appropriate doses of aerosolized drugs, and confirm the clinical relevance.

The results prove that the combination of trans-nasal inhalation with noninvasive pressure support ventilation leads to significantly increased particle deposition in the lung.

No abstract

Previous studies showed a reduced hypercapnic ventilatory response (HCVR) in patients with COPD. However, the association between HCVR and COPD GOLD stages is unknown. The measurement of the HCVR is a methodological option to test the function of the breathing feedback cycle. The aim of this feasibility study was to present a new automatic and standardized device (MATAM) to measure and interpret the HCVR. This device determines if exposure to CO2 leads to an adequate increase in breathing frequency and tidal volume. Recordings are performed in a closed system that allows selective changes of each gas component. The minute ventilation (AMV) under hypercapnic stimulation is plotted against the end-tidal CO2 (ETCO2). The HCVR is defined as the linear regression line.28 patients (18 male; 10 female) with COPD GOLD stages 0 to IV were studied. The patients had a mean age of 57 ± 14 (standard deviation) years and a mean BMI of 32 ± 9 kg/m(2). We could show that the HCVR measurement in patients with COPD using MATAM was feasible. Patients with more severe COPD stages had a significantly more reduced HCVR. This could be an indication of reduced chemosensitivity due to a worsening of blood values (pH and pCO2) which affect the central chemoreceptors in the long term. Further studies will be needed to validate the MATAM device for healthy individuals and other patient groups, and for the investigation of standard values.