Effect of Regular Use of High-dose Nebulized β2-Agonists on Resting Energy Expenditure, Weight, and Handgrip Strength in Patients With Chronic Airflow Limitation: Materials and Methods

CAL was defined as prebronchodilator FEVl <60% predicted, FEV/FVC ratio <65%, and reversibility of FEV1 <15% following 200 |jLg of salbutamol via an MDI. A nebulizer assessment in our unit consists of an 8-week protocol of 4 X 2-week periods with different treatment regimens with daily home peak expiratory flow (PEF) monitoring throughout using a flowmeter (Mini-Wright PEF meter; Clement Clarke International; Harlow Essex, UK). Bronchodilator treatment progresses from standard-dose MDI inhaled bronchodilators (two puffs four times a day), to high-dose MDI inhaled bronchodilators (four puffs four times a day), to nebulized β2-agonists, and finally nebulized β2-agonists plus nebulized ipratropium bromide. Before each assessment, baseline spirometry was measured by a dry wedge spirometer (Vitalograph Ltd; Lenexa, Kan) at least 4 h after any inhaled β2-agonist medication.

REE was measured in the first week of the assessment when the treatment was two puffs of salbutamol via an MDI + large-volume spacer (Volumatic; Allen & Hanburys; GlaxoWel-lcome; Research Triangle Park, NC) four times daily (ie, 800 μg salbutamol per day). Measurement of REE was always made at least 6 h after the previous dose; studies of acute effects of β-agonists on REE have shown return to baseline by 2 h. The patient then continued with the assessment following which the result of the home PEF monitoring and subjective benefit scores were assessed by a physician independent of this study, and as per published criteria. If indicated by these criteria, a home nebulizer (Unineb Nebuliser; Unimed; UK) and compressor (Medix AC 2000 High-flo Neb; Medix; Baldock Herts, UK) were then provided with a prescription for regular high-dose salbutamol, 5 mg qd (plus ipratropium bromide, 500 jig qd if this drug had led to further improvement over and above salbutamol).