Can all patients with COPD use the correct inhalation flow with all inhalers and does training help?

The inhalation rate is important when patients use an inhaler. Dry powder inhalers (DPIs) require an inhalation rate >30 L min(-1) whereas metered dose inhalers (MDIs) should be used at <90 L min(-1). Within the setting of a routine clinic, we have measured peak inhalation flows (PIF) of COPD patients when they used a Diskus (SDSK), Turbuhaler (STBH), Handihaler (SHAND) and MDI. Subjects were then randomised into trained (VT) and non-trained (NT) groups. One hundred and sixty-three patients with a mean (S.D.) age and % predicted FEV(1) of 72.5 (9.9) years and 47.8 (22.2)% completed the study. Of the patients, 4.9%, 14.2% and 57.0% inhaled <30 L min(-1) through SDSK, STHB and SHAND, respectively and 59.5% inhaled >90 L min(-1) with the MDI. Generally, the more severe the COPD, the slower was their PIF with all inhalers. The MDI PIF values in the VT group (n=84) post-training were significantly (p<0.001) slower but there was no change for the DPIs. Of the 55 VT patients inhaling >90 L min(-1) through the MDI only 7 (p<0.001) inhaled too fast post-training. Pre-training 3, 15 and 46 VT subjects inhaled <30 L min(-1) through the SDSK, STBH and SHAND and after training none, 5 and 26 did not inhale faster than this minimum required rate. Some COPD patients have problems achieving required PIFs through DPIs but training is useful to help some exceed the minimum required rate despite only small improvements. The patients found it easier to slow their PIF through the MDI.

The potential of a 2Tone Trainer to help patients use their metered-dose inhalers.

BACKGROUND: Many patients have problems using the correct inhalation technique when they use their metered-dose inhalers (MDIs). We have investigated whether a training aid (2Tone Trainer [2T]; Canday Medical Ltd; Newmarket, UK) helps to maintain the correct inhaler technique after patients leave the clinic METHODS: Ethics committee approval was obtained, and patients gave consent. Asthmatic patients who had been prescribed an MDI had their inhalation technique assessed. Their peak inhalation flow (PIF) when using their MDI, FEV(1), and the Juniper asthma quality of life questionnaire (AQLQ) score were measured. Those patients using the recommended MDI technique were the good-technique (GT) group. The remainder were randomized to receive verbal training (VT) or VT plus the 2T to improve their MDI technique. All patients returned 6 weeks later. RESULTS: There were 36, 35, and 36 asthmatic patients, respectively, who completed the GT, VT, and 2T procedures. FEV1 did not change within all groups between visit 1 and 2. PIF and AQLQ score did not change in the GT group. In the VT and 2T groups, the AQLQ score increased by mean differences of 0.33 (95% confidence interval [CI], 0.14 to 0.53; p < 0.001) and 0.74 (95% CI, 0.62 to 0.86; p < 0.001). At visit 1, all patients in the VT and 2T groups inhaled > 90 L/min decreasing to 12 patients and 1 patient, respectively, at visit 2 (p < 0.001 both groups). The overall changes in the 2T group for PIF and AQLQ score, between visits 1 and 2, were significantly (p < 0.001) greater than the corresponding changes in the VT group. CONCLUSION: The 2T helps patients to maintain the recommended MDI technique posttraining with improvements in AQLQ score.