Improved targeting of beclomethasone diproprionate (250 micrograms metered dose inhaler) to the lungs of asthmatics with the Spacehaler.

The Spacehaler (Evans Medical Ltd, Leatherhead, U.K.) is a new, compact, inhaler device containing the same aerosol canister as a conventional metered dose inhaler (MDI). However, the design of the Spacehaler has been shown to reduce the velocity of the aerosol, thus reducing the proportion of non-respirable particles delivered to the patient. This study compared radioaerosol deposition patterns following inhalation of 250 micrograms of beclomethasone dipropionate from the Spacehaler and a conventional MDI (Beclazone, Norton Health Care, Harlow, U.K.). After rigorous in vitro validation of the radiolabelling technique, 12 asthmatic subjects (seven men aged 20-69 years, mean baseline FEV1 2.59 1 (SD 0.55 1) received one dose of 99mTc-labelled beclomethasone dipropionate 250 micrograms via either a Spacehaler or MDI on each of two study days in a randomized cross-over manner. All subjects had been taught the required inhalation technique before the dose was administered. Inhalation details were recorded using a spirometer connected in series with the device. Lung and oropharyngeal depositions were measured by gamma scintigraphy. The mean percentage of the metered dose deposited in the lungs was 23.0% (SD 8.3%) for the Spacehaler and 12.8% (SD 6.8%) for the MDI (P < 0.01). However, there was no significant difference in the distribution patterns within the lungs between the two devices. Oropharyngeal deposition was significantly lower (P < 0.01) for the Spacehaler than for the MDI [mean (SD) 27.9% (16.4%) and 73.6% (8.7%), respectively] whilst the percentage of the metered dose remaining on the Spacehaler actuator was significantly greater than that on the MDI actuator [mean (SD) 48.0% (11.8%) and 12.4% (8.5%) respectively, P < 0.01]. There was evidence from the inhalation recordings that some patients experienced the 'cold Freon effect' whilst using the metered dose inhaler which may have contributed to the lower lung deposition seen with this device. This study demonstrates that the proportion of a 250 micrograms dose of beclomethasone dipropionate that is delivered to the lungs is significantly greater with the Spacehaler than the MDI. The Spacehaler also reduces the proportion of the does that is deposited in the oropharynx to less than half that observed with the MDI, and reduces the total dose of drug received by the patient.

The Spacehaler for delivery of salbutamol: a comparison with the standard metered-dose inhaler plus Volumatic spacer device.

The Spacehaler is a new, compact, pressurized aerosol device that uses the same canister as a conventional metered-dose inhaler (MDI). Its design, however, reduces the velocity of the aerosol cloud that emerges from the inhaler, thereby reducing the amount of the non-respirable fraction of the drug delivered to the patient. Large volume spacers achieve a similar effect, but they are bulky and therefore inconvenient to use and carry around. This study compared the bronchodilator effect of 200 micrograms salbutamol delivered by the Spacehaler to that of an MDI used with a Volumatic spacer (MDI plus spacer) in patients with reversible obstructive airways disease. Twenty-five patients with asthma, having a forced expiratory volume in 1 s (FEV1) between 50 and 90% predicted and a reversibility of > or = 15% to 200 micrograms salbutamol given by the conventional (standard) MDI entered the study. On two separate study days, they inhaled 200 micrograms salbutamol either via the Spacehaler or the MDI plus spacer. To maintain blinding, they received placebo on both study days via the alternate device. Their FEV1, forced vital capacity (FVC) and peak expiratory flow (PEF) were measured before and at regular intervals for 6 h after inhalation. Assessment of equivalence between the two devices was based on whether the 90% confidence interval for the difference between the weighted mean FEV1 was within +/- 0.25 1. Patient preference was assessed by a questionnaire at the end of the second study day. Twenty-four patients completed the study. Both devices produced a significant improvement in FEV1 (P < 0.02). The upper and lower 90% confidence limits for the difference in weighted mean FEV1 between the devices was +/- 0.041, and the 99% confidence limits were +0.061 and -0.071. The weighted means for FVC and PEF, and the duration of effect and peak responses for FEV1, FVC and PEF also showed no difference between the two devices. Patients found no difficulty in using the Spacehaler, and 20 out of 24 patients (83.3%) preferred it to the MDI plus spacer. The bronchodilator effect of 200 micrograms salbutamol administered by a Spacehaler was equivalent to that produced by an MDI plus spacer in this group of patients with reversible airways obstruction. The majority of patients preferred it to a large volume spacer.