Comparison of the Diskus inhaler and the Handihaler regarding preference and ease of use.

Many chronic obstructive pulmonary disease (COPD) patients use their inhaler ineffectively and there is a trend towards increased inhaler resistance. We wanted to answer two questions: Is there a difference in preference and ease of use between Diskus (DK) and Handihaler (HH)? How acceptable are inhalation resistances? Sixty COPD patients, naive to DK and HH, but experienced in the use of other inhalers, had to read the instruction leaflet and demonstrate their inhalation technique. If errors were made, instruction was given and inhalation technique was checked again. Patients had to state a preference for DK or HH. Subsequently they inhaled through a range of resistances and scored the acceptability. There was no difference in the number of instructions needed for both inhalers. One third inhaled perfectly after reading the instruction leaflet, which increased to 85% after one instruction. More patients preferred the DK (43) than the HH (16). With decreasing resistance acceptability increases, but it reaches a plateau. Patients have a clear preference for the DK. There is no difference in the number of instructions needed to obtain a perfect inhalation technique, but for some patients one instruction is not enough. The trend to increase the resistance of inhalers has reached a critical point with regard to acceptability.

The course of inhalation profiles during an exacerbation of obstructive lung disease.

BACKGROUND: Acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD) are associated with increased airflow Limitation, hyperinflation and respiratory muscle fatigue. It is unclear, whether patients are able to perform adequate inhalations through various inhalation devices with different orfices during an exacerbation. The aim of this study was to examine the evolution of inhalation profiles of patients inhaling through Diskus, Turbuhaler, pressurized metered dose inhaler (pMDI) and Volumatic and consequently the appropriateness of using the various devices during an exacerbation. MEASUREMENTS: 15 hospitalized patients participated in this randomized comparison of inhalation profiles through the four placebo-devices. For each device, triplicate inhalation profiles were recorded during day 1-9 of admission and in stable phase (day 50). RESULTS: The mean percentage of patients performing optimum inhalation profiles was 100% for Diskus, 60% for Turbuhaler, 14% for pMDI and 87% for Volumatic over the interval of day 1-9 and day 50. Patients with an inspiratory muscle strength (MIP) of less than 6kPa were generally unable to generate the optimum flow through the Turbuhaler (>60 l/min). CONCLUSION: The Diskus and Volumatic can be used effectively in the acute phase of an exacerbation of asthma or COPD. The Turbuhaler could be optimally used after the fifth day of convalescence. The pMDI is rather unsuitable during an exacerbation.

Does the inhalation device affect the bronchodilatory dose response curve of salbutamol in asthma and chronic obstructive pulmonary disease patients?

OBJECTIVE: This open randomized study examined differences between the effects of an equal dose of salbutamol administered via the Diskus, Turbuhaler, and pMDI plus Volumatic. Measurements included dose response curves, dynamic and static lung volumes, respiratory muscle strength, and systemic effects. METHODS: The cumulative dose-response study compared the biological effects (pulmonary function, respiratory muscle function, systemic effects) of an equal dose of salbutamol delivered via four different devices in 23 patients with asthma and 21 patients with moderate or severe chronic obstructive pulmonary disease (COPD). RESULTS: Salbutamol via Volumatic showed significantly better bronchodilation than via pMDI or Turbuhaler in both patient groups. No significant difference was found between salbutamol via Volumatic and Diskus. However, the advantage of Volumatic is of marginal clinical relevance since the additional bronchodilation was a maximum of 140 ml FEV(1) and did not exceed the minimal patient-perceivable improvement. In the asthma group a more evident plasma K(+) decrease was found after salbutamol delivered via pMDI and pMDI plus Volumatic. Furthermore, especially in the COPD patients a significant decrease was observed in hyperinflation and consequently an improvement in maximal inspiratory pressure as a result of salbutamol via all devices. CONCLUSIONS: Bronchodilation by salbutamol was slightly more effective via Volumatic than via pMDI or Turbuhaler. No significant difference in bronchodilation was found between salbutamol via Volumatic and Diskus. The advantage of Volumatic is not of clinical relevance.

In Check Dial: accuracy for Diskus and Turbuhaler.

OBJECTIVE: The In Check Dial was developed to evaluate whether a patient is able to generate an adequate peak inspiratory flow (PIF) through a certain inhalation device. The inhalation profile recorder (IPR) is a calibrated instrument that measures flows through Diskus and Turbuhaler in our research setting. The aim of this study was to compare the PIFs of patients when inhaling through a Diskus or Turbuhaler connected with the IPR (PIF_diskus and PIF_TH) to the flows through the corresponding orifices of the In Check Dial (Diskus_In Check and TH_In Check). METHODS: Twenty-four stable asthma and twenty-one chronic obstructive pulmonary disease (COPD) patients inhaled, on two separate occasions, in randomised order, via the Diskus or Turbuhaler connected with the IPR. Subsequently, patients inhaled through the In Check Dial using the orifices of Diskus or Turbuhaler. RESULTS: The difference between Diskus_In Check and PIF_diskus was 3.9 (11.9)l/min (P=0.038). The difference between TH_In Check and PIF_TH was 3.5 (10.6) l/min (NS). All Diskus- and Turbuhaler-inhalations were performed with the minimum required flow of 30 l/min. However, four COPD patients inhaled with the non-optimal flow (<60 l/min) through the Turbuhaler. The In Check Dial did not indicate two of them. CONCLUSION: Measuring PIF through Diskus and Turbuhaler using the IPR and the In Check Dial, respectively shows a disagreement of 3.9l/min. A disagreement of 3.5l/min was found for the Turbuhaler. The In Check Dial did not identify two of four patients as 'non-optimal' users.