The value of inhaled drugs has been recognised for millenia by ancient
civilizations (Miller, 1973). Inhalation therapy has many advantages
including drug delivery direct to site of action, rapid onset of therapeutic
effect (Plit et aI, 1972) minimisation of dose required (Newman &
Clarke, 1985) minimisation of systemic side-effects (Sterling, 1978),
avoidance of first pass metabolism (C & D Livingstone, 1988) and noninvasive
delivery technique. However, specific drug delivery may be
hindered by defence mechanisms of the respiratory tract (Reiser &
Warner, 1986), and other problems may also be present since drug
delivery depends on the mechanism of deposition (Newman, 1984),
particle size (Rees et aI, 1982), inhalation mode (Pavia et aI, 1977) and
patient factors. The types of drugs used in inhalation therapy include
the beta adrenergic stimulants, anticholinergic bronchodilators,
methylxanthines, sodium cromoglycate, corticosteroids, water and saline
aerosols, mucolytics and antibiotics. The delivery systems employed are
the nebuliser, dry powder inhalers and the metered dose inhalers
(MDls). Recently, a new device has been developed, and this is the
Turbohaler.peer-reviewe

Micallef, Ivan P.

OAR@UM

INHALATION THERAPY IN OBSTRUCTIVE AIRWAYS DISEASE: EVALUATION AND INSTRUCTION OF METERED DOSE INHALER TECHNIQUE Ivan P. Micallef Introduction The value of inhaled drugs has been recognised for millenia by ancient civilizations (Miller, 1973). Inhalation therapy has many advantages including drug delivery direct to site of action, rapid onset of therapeutic effect (Plit et aI, 1972) minimisation of dose required (Newman & Clarke, 1985) minimisation of systemic side-effects (Sterling, 1978), avoidance of first pass metabolism (C & D Livingstone, 1988) and non-invasive delivery technique. However, specific drug delivery may be hindered by defence mechanisms of the respiratory tract (Reiser & Warner, 1986), and other problems may also be present since drug delivery depends on the mechanism of deposition (Newman, 1984), particle size (Rees et aI, 1982), inhalation mode (Pavia et aI, 1977) and patient factors. The types of drugs used in inhalation therapy include the beta adrenergic stimulants, anticholinergic bronchodilators, methylxanthines, sodium cromoglycate, corticosteroids, water and saline aerosols, mucolytics and antibiotics. The delivery systems employed are the nebuliser, dry powder inhalers and the metered dose inhalers (MDls). Recently, a new device has been developed, and this is the TurbohalerR. Correct patient technique in inhaler use is critical for the success of therapy. Although correct MDI use involves a relatively simple procedure, studies have shown that patients often administer aerosol drug incorrectly. PattersOn and Crompton [1976] found that 14% of patients had an 'inefficient' technique. In contrast, Orehek et al [1976] reported that 75% of inhaler users failed to administer them correctly. Other reports have placed the number of patients misusing their inhalers between. these two extremes (Earis & Bernstein [1978];. Epstein et al [1979]; Gayrard & Orehek [1983]; Shim & Williams [1980]; Augusti et al [1985]; Saunders [1985]). Since the pharmacist is often the last link prior to the patient using the devices, he has an obligation to the patient to ensure that the medicine is administered correctly. The objectives of this study were to: a) Assess the technique of local inhaler users, determine the major problems and correlate the results with those of other countries b) Examine the most effective method of instruction c) Determine the importance of reinstruction 544 d) Evaluate the hypothesis that poor inhaler technique may be perpetuated by clinical staff Method Study 1: Inhaler technique assessment An expansion of the correct inhaler technique recommended by Newman and Clarke [1984] was developed and used throughout the study. In this study, the ability of 141 patients to use their MD! was assessed by applying a scoring system to each step of the technique. Table 1: Correct MD! technique and scoring system used Step 1. Ensure that the canister is firmly inserted in the case and is not below room temperature 2. Remove the cap, shake well and hold upright 3. Breathe out in a relaxed fashion 4. Hold head upright and tongue relaxed 5. Place the mouthpiece in mouth and close lips tightly around it 6. Breathe in deeply and while doing so, press metal canister firmly into the adapter 7. Release the pressure on the metal canister, remove the mouthpiece from the mouth and hold breath for 10 seconds 8. Breathe out slowly through the nose Max Score 5 15 10 10 15 20 15 10 Due to the subjective nature of this assessment, two precautions were observed: a) Each patient was assessed by two investigators, each one being unaware of the other investigator's scores b) Each step of the technique had a score range which indicated the patient's exact performance 545 Each patient was then asked to answer a short questionnaire which supplied information regarding demographic data, the disease and its severity, treatment and compliance, patient characteristics related to MDI use and patients' attitudes and beliefs. In addition, spirometry was performed on patients aged 0 - 11 years and a mental status questionnaire was compiled for patients over 60 years old. Study 2: Phase 1: Instruction methods a) Volunteer study A pilot study was performed amongst 36 volunteers who had no previous experience in the use of MDIs. These were randomly assigned to one of 3 groups: i) Group A (written instruction): each volunteer was given a manufacturer's written instruction package insert (VentolinR Inhaler, M500050 1188) i i ) Group B (personal instruction): each volunteer was instructed personally with a correct inhaler technique demonstration and instruction sheet i i i) Group C (video instruction): a video presentation on the correct use of MDIs was prepared "in-house" and shown to the volunteers The volunteers of each group were then given a placebo to practice with and their technique was then assessed. This study was performed to obtain a baseline reference for instruction methods. b) Patient study The 141 patients were divided into similar 3 groups and the instruction was given and assessment performed as in the volunteer study. Study 2: Phase 2: . Reassessment after 4 weeks The patients had their technique reassessed in the same way as it was initially assessed. All the above data was subjected to statistical analysis. 546 Study 3: Inhaler technique and the clinical staff The advice on inhaler technique given unawares by a number of health care professionals and pharmacy technicians was recorded. The investigator presented himself as a recently diagnosed asthmatic patient who had been prescribed an MDI for the first time and was asking for advice. This survey was carried out to determine whether clinical staff were responsible for the fact that poor technique is still so widespread. A questionnaire was also issued to investigate the degree of familiarity of physicians and pharmacists with aerosol therapy. Results: Table 1: Distribution of patients in the study Instruction Males Females Age Range in years (%) Group (%) (%) 0-11 12-18 19-59 >60 Manufactu-rer's sheet 17.7 12.8 3.5 12.1 8.5 6.4 Personal 29.8 18.4 13.5 14.9 12.8 7.1 Video 14.2 7.1 4.3 7.1 7.8 2.1 Table 2: Summary of results obtained from the patient questionnaire regarding MDI use Average duration of MOl use: 5.74 years Daily use: 61.7% Previous instruction given: 81.6% Instruction given by physician: 85.8% Additional instruction received: 29.1% Satisfied with technique prior to instruction: 78% Physical and mental problems with MDI use: 4.3% Appreciate educational material: 97.9% Written form: 8.0% Personal form: 76.15 Audio-visual form: 20.3% 547 Table 3: Mean scores for the 3 different instruction groups on the 3 assessment days Instruction Group Manufactu-rer's sheet Personal Video Initial Assessment after Assessment Instruction % Score % Score Mal N.Ire Mal N.Ire 55.51 NRIS 66.24 61.87 59.21 NRIS 77.25 80.25 58.52 NRIS 77.50 75.00 NRIS - Not Recorded In Study Mal - Malta N.Ire - N. Ireland (McElnav et al. 19R9) 100 80 60 40 20 Figure 1: Evaluation of individual steps in patient inhaler technique Patients (%) 2 345 6 Step number 7 Assessment 4 Weeks after Instruction % Score Mal N.Ire 64.16 59.13 72.79 74.38 73.63 62.50 8 _ Mln score achieved ~ Mln score unachleved 548 70 60 50 40 30 20 10 o Discussion Figure 2: Inhaler technique in part of the clinical staff % Physicians Pharmacists Health professional - Adequate technique ~ Inadequate technique Although it is now widely accepted that drug administration by inhalation is preferable to oral therapy, 33.33% of the patients in this study failed to have an adequate inhaler technique. The average inhaler technique was quite low (57.93 points), a score close to the lower boundary of the satisfactory range. Incorrect use diminishes the therapeutic effect and such a phenomenon was more common in the two extreme age groups, i.e., 0 - 11 years and> 60 years. The only compliance problem in the latter group was that of language (from Mental Status Questionnaire); this indicates poor hand-lung coordination and lack of proper instruction (only 36.17% had been given reinstruction prior to this study) as the major factors contributing to poor MD! technique. The pilot volunteer study indicated personal demonstration and counselling, and video as efficient instruction methods. Such results were 549 reflected in the patient study: patient instruction by the use of a manufacturer's package insert was not enough and is in no way an alternative to personal or video instruction. Score improvements in the latter two groups were approximately equal and double that in the written instruction group. However, although video was found to be as effective as personal tuition, 76.1 % of the patients prefered educational material in the personal form, with only 20.3% preferring the video. This should be further investigated since it indicates that video is as effective and less time-consuming than personal instruction, but is not as accepted by the patients· The importance of reinstruction was demonstrated by the decrease in technique score observed in patients of all three instruction groups after four weeks. The lowest decrease was in the written instruction group, but this was only a reflection of the poor initial scores. The results obtained locally correlated well .with those of McElnay et al (1989), except for the video assessment score recorded 4 weeks after instruction, were the total technique score decrease was much lower in this study than that reported by McElnay (4.99% compared to 16.67%). The results obtained in the study concerned with health professionals support the hypothesis that poor inhaler technique may be perpetuated by clinical staff and that the latter are partly responsible for the fact that poor MDI technique is still so widespread. 37.5% of the physicians, 53.5% of the pharmacists'and 66.7% of the pharmacy technicians failed to have an adequate MDI technique, but although highly significant they are not as alarming as those recorded in other countries. A parodoxical result was also observed in that although 80.14% of the patients believed that the pharmacist could provide such education, 32.62% of the patients had negligible confidence in their pharmacist. Conclusion The following conclusions can be drawn from the results that were obtained: a) 33.33% inadequate MDI users reflect the need of proper instruction and education b) Video instruction is as effective but less time-consuming than personal instruction and should therefore be employed in dispensary and out-patient waiting-rooms 550 c) Technique deterioration with time did not differ between patients given a written instruction sheet to take home and those that were not given are, thus indicating the relative ineffectiveness of such an educational method in this case d) The average pharmacist should be more competent and motivated in order to increase patient compliance in inhalation therapy References: Augusti AGN, Ussetti P, Roca J, Montserrat JM, Rodriguez-Roisin R, Augusti-Vidal A (1985) Proper use of metered-dose inhalers. Carina and Duncan Livingstone (1988) Inhalation therapy (Drug delivery). Pharmaceutical Journal Oct 8: 476-478 Earis JE, Bernstein A (1978) Misuse of pressurised nebulisers. Medical Journal 1:1554 British Epstein SW, Manning CPR, Ashey MJ, Corey PN (1979) Survey of the clinical use of pressurised aerosol inhalers. Can Med Assoc J 120:813-816 Gayrard P, Orehek J (1983) Inadequate use of pressurised aerosols by asthmatic patients. Respiration 40:47-52 McElnay et al (1989) Audiovisual demonstration for patient counselling in the use of pressurised aerosol bronchodilator inhalers. J of Clin Pharm & Therap 14:135-144 Miller WF (1973) Aerosol therapy in acute and chronic respiratory disease. Ann Intern Med 131:148-155 Newman (1984) Therapeutic inhalation agents and devices. Inhalation therapy Vo!. 76 No. 5 ,Postgraduate medicine Newman SP, Clarke SW (1984) The proper use of metered dose inhalers. Chest 86:342-344 Newman and Clark (1985) Aerosols in therapy; in Aerosols in Medicine (ed. Moren, Newhouse, Dolovich) 551 Orehek J, Gayrard P, Grimaud EH, Charpin J (1976) Patient error in use of bronchodilator metered aerosols. British Medical Journal 1:76 Paterson DC, Crompton GK (1976) Use of pressurized aerosols by asthmatic patients. British Medical Journal 1:76-77 Pavia, Thomson, Clark (1977) Effect of lung function and mode of inhalation on penetration of aerosol into human lung. Thorax 32(2):194-197 Plit, Goldman, Cassel, Zwi (1972) Med. Proc. 18:41-45 Rees, Clark, Moren (1982) Eur. J.Resp. Dis. 63:Suppl. 119:73-78 Reiser and Warner (1986) Inhalation treatment for asthma. of disease in childhood .61:88-94 Archives Saunders KB (1985) Misuse of inhaled bronchodilator agents. Br Med J 1:1037-1038 Shim C, Williams HM (1980) The adequacy of inhalation of aerosols from canister nebulisers. American Journal of Medicine 69:891-894 Sterling (1978) British Medical Journal 1:1259-1262 552 

Inhalation therapy in obstructive airways disease : evaluation and instruction on metered dose inhaler technique

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Inhalation therapy in obstructive airways disease : evaluation and instruction on metered dose inhaler technique

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