Eur Respir J 1990, 3, 584-585

Comparison of terbutaline via the Nebuhaler and salbutamol via the Volumatic: theory and practice

B.J. Chapman, G.K. Crompton

Comparison ofterbutaline via the Nebuhaler and salbutamol via the Volumatic: Correspondence: Dr B.J. Chapman, Department of theory and practice. B.J. Chapman, G.K. Crompton. Geriatric Medicine, City Hospital, Edinburgh EHlO 5SD, UK. ABSTRACT: The bronchodllatlng efficacy of terbutaUne (250 ~g·puff) inhaled via the Nebubaler and salbutamol (100 ~g·puff) Inhaled via the Keywords: Asthma, B1 -agonist therapy, space Volumatic has been studied ln 30 patients with reversible obstructive airways devices. disease in a randomized crossover study. The salbutamoi/Volumatlc combination produced significantly greater broncbodllatatlon than Received: November 1988; accepted after revision, 3 terbutaline/Nebuhaler (one puff, p

Deposition studies [ 1, 2] and clinical comparisons at least 20% on day 1. Baseline FEV1 values on the two [3, 4] have shown that a 750 ml pear-shaped spacer device days varied by less than 15% in all patients. The results (Nebuhaler, Astra Phannaceuticals) significantly increases were analysed using paired t-tests to compare the changes • the delivery and bronchodilating effect of terbutaline in FEV1 administered from a metered dose inhaler (MDI). A similar spacer device (Volumatic, Allen and Hanbury Phannaceuticals) is now available for use in conjunction 2.2 with salbutamol MDis, but its effectiveness has yet to be established. To compare the two spacer devices, we have FEV1 measured the bronchodilating effects of equal numbers I 2 .0 of actuations of terbutaline and salbutamol given via the Nebuhaler and Volumatic, respectively. 1.8

Patients and methods 1.6

Thirty subjects (17 male, l3 female; aged 20-74 yrs mean 50 yrs) with reversible chronic obstructive lung disease were studied on two separate days when they 0 20 40 received terbutaline (Bricanyl) 250 ~g·puff via the M in Nebuhaler and salbutamol (Ventolin) lOO ~g·puff via the ) Fig. 1. - Mean forced expiratory volume in one second (FEV 1 values Volumatic in random order. On each visit, they inhaled in 30 patients inhaling salbutamol via Volumatic and teroutaline via one puff of bronchodilator the spacer, followed via Nebuhaler. Mean FEV1±sBM; • : p

Discussion Aclurowledgemenls: We are grateful to the Respiratory Measurement Technicians for performing lhe pulmonary function tests. The development of spacer devices like the Nebuhaler and Volumatic was based on the principle that they would act as holding chambers in which aerosol particle size References and velocity could decrease and thereby increase the penetration of particles to the airways [5]. The Nebuhaler 1. Newman SP, Monm F, Pavia D, Little F, Clarke SW. - is pear-shaped corresponding to the shape of the aerosol Deposition of .pressuri~ed suspension aerosols inhaled cloud emerging from the terbutaline MDI. In contrast, through extension devices. Am Rev Respir Dis, 1981, 124, 317-320. the Volumatic is symmetrical in outline and shorter than 2. Newman SP, Millar AB, Lennard-Iones TR, Moren F, the Nebuhaler, despite the fact that the salbutamol MDI Clarke SW. - Improvement of pressurised aerosol deposition aerosol particles emerge at a higher velocity. In vitro with Nebuhaler spacer device. Thorax, 1984, 39, 935-941. studies have suggested that there is greater deposition of 3. Cushley MI, Lewis RA, Tattersfield AE. - Comparison Ventolin in the Volumatic compared with Bricanyl in the of three techniques of inhalation on the airway response to Nebuhaler (78% vs 62%) (Andersson J., unpublished terbutaline. Thorax, 1983, 38, 908-913. results. AB Draco, Lund, Sweden). The present study 4. Morris I, Milledge JS, Moszoro H, Higgins A. - The was designed to assess if the theoretical advantages of efficacy of drug delivery by a pear-shaped spacer and metered the terbutaline/Nebuhaler combination were reflected in dose inhaler. Br J Dis Chest, 1984, 78, 383- 387. practice. We chose to compare one actuation of each 5. Newman SP, Clarke SW. - Therapeutic aerosols 1 - MDI in the belief that any increased efficiency of drug Physical and practical considerations. Thorax, 1983, 38, 881-886. delivery would be more readily apparent with low doses 6. Freedman BI. - Trial of a terbutaline aerosol in of ~2-agonist (2]. the treatment of asthma and a comparison of its effects with The finding that the salbutamoi/Volumatic those of a salbutarnol aerosol. Br J Dis Chest, 1972, 66, combination was more effective is surprising and the 222-229. explanation is not at all clear. There was no evidence to 7. Sirnonsson BG, Stiksa I, Strom B. - Double blind trial suggest the Nebuhalers used were faulty with, for with increasing doses of salbutarnol and terbutaline aerosols in example, sticky valves. They were inspected carefully patients with reversible airways obstruction. Acta Med Scand, and the valves appeared to function normally. The fact 1972, 192, 371-376. this was an open study raises the possibility of observer 8. Harris L. - Comparison of cardiorespiratory effects of bias. However, the respiratory measurement technicians terbutaline and salbutarnol aerosols in patients with reversible airflow obstruction. Thorax; 1973, 28, 592-595. were all experienced and reliable workers, and we know 9. Choo-Kang YFI, MacDonald HL, Home NW. - A of no reason why any bias should have occurred. Also, comparison of salbutarnol and terbutaline aerosols in bronchial the data were not analysed until the completion of the asthma. Practitioner, 1973, 211, 801-804. study. 10. Bennis I, Svedrnyr N. - A controlled comparison of 1l1is study has assumed that l OO }.l.g salbutamol and salbutamol and terbutaline inhaled by IPPV in asthmatic 250 }.l.g terbu taline have equal bronchodilaling efficacy patients: a dose response study. Scand J Resp Dis, 1977, 58 [6-9]. We know of no evidence to the contrary. A (Suppl. 101). 113-117. possible explanation Ues in the higher velocity of the salbutamol MDI particles causing greater impaction Comparaison de la terbutaline administree par le Nebuhaler et of aerosol particles in the oropharynx with a du salbutamol administre par le Volumatic: rheorie et pratique. corresponding reduction in bronchodilating emcacy. One B. Chapman, G. Crompton. puff of salbutamol may appear equipotent to one puff of RtSUME: L'efficacite bronchodilatatrice de la tertutaline (250 tcrbutaline when inhaled directly from the MDI, but the Jig·bouffee) inhalee par le Nebuhaler, et du salbutarnol (100 addition of the spacer may reduce the negative effect of fi&·bouffee) inhale par le Volumatic, a ete etudiee chez 30 the higher salbutamol particle velocity and thus make the patients atteints de maladie obstructive reversible des voies salbutamoi/Volumatic combination appear more aeriennes dans une etude random.isee avec permutation croisee. effective. However, this seems an unlikely explanation La combinaison Volumatic/salbutamol a provoque une dilatation significativement plus marquee que tertutaline/ since when given by IPPY, 100 }.l.g salbutamol appears Nebuhnlcr (une bouffee, p