Discussion This is a hospital-based study that was conducted on 100 patients attending the Department of Respiratory Medicine in a tertiary-care hospital

Etudes

Discussion
This is a hospital-based study that was conducted on 100 patients attending the Department of Respiratory Medicine in a tertiary-care hospital, Pune, Maharashtra to assess the correctness of inhaler technique among its users.
1. Age and Sex: In our study Mean age of study sample is 55.8 years with standard deviation of 15.81 years, with the highest 85 yrs and lowest 16 years. There were 71 (71%) males and 29 (29%) females in the study.

When we compare our study with the study by Saxena et al53 conducted on a purposive (nonrandom) sample of patients attending the Department of TB and Chest Diseases, FH Medical College and Hospital, Uttar Pradesh it has been seen that in their study most of the study subjects were male subjects (70%). The mean age of the study subjects was found to be 51 ± 14 years which correlates with our study. We can also correlate our study with the study by Arora et al,58 done in Lala Ram Sarup Institute of Tuberculosis and Respiratory Diseases, New Delhi, India where the male female ratio of the enrolled participants was 4:1 with a mean age of 42.59 years (SD ±14) which is similar to our study.
2. Diagnosis: Global Initiative for Chronic Obstructive Lung Disease and Global Initiative for Asthma reported 60% uncontrolled COPD and asthma patients worldwide.5,6 In our study, there were 51 (51%) bronchial asthma subjects among study samples, while 49 (49%) were having COPD. But there is no significant difference in the prevalence (p=0.8423) of both the diseases. In the study by Saxena et al53 62.8% (59 of 94) patients were experiencing COPD, while 37.2% (35 of 94) were patients of bronchial asthma.

In another study by Arora et al,58 out of the 300 subjects, 188 (62.7%) were known/diagnosed cases of COPD and 112 (37.2%) were Bronchial Asthma. In the above mentioned studies done in North India both showed more cases of COPD than bronchial asthma while in our area bronchial asthma prevalence is more than COPD however the difference is not significant.

3. Association with smoking: The World Health Organization and the Global Alliance against Chronic Respiratory Diseases identified the most important risk factors for respiratory diseases as: tobacco smoke, indoor and outdoor air pollution, allergens, occupational agents, diet and nutrition, and pulmonary infections.59,60 In our study the history of smoking was present more in COPD Subjects (61%) than bronchial asthma subjects (31%). There was association between smoking history and diagnosis of subjects (p = 0.003). However we have not distributed the subjects into male and female smokers and ex smokers and smokers.

In the study by Ganguly ,et al46 among male subjects 38.1% were smoker, 36.4% ex-smokers & 25.5% non-smoker. No female subject has smoking habit. They have not shown the association between smoking history and diagnosis (COPD/Bronchial asthma). In another study by Sehajpal R et al48 42.6% were ex-smokers and 15.4% were smokers. They also had not shown any association of smoking with the diagnosis.

4. Distribution of subjects according to use of inhalation devices: In our study there were 32 (32%) study samples using DPI single dose inhalation device, followed by 31(31%) PMDI device, 30 (30%) were using PMDI with spacer while 7 (7%) were using DPI multi dose inhalation device. In another study by Arora et al,58 DPI users (n = 130, 43.3%) were the highest among the enrolled population followed by MDI (n = 70, 23.3%), MDI with Spacer (n = 50, 16.7%) and Domiciliary Nebulizer (n Z 50, 16.7%) users which correlates to our study. In another study by Pothirat et al51 Accuhaler users (n=83, 41.5%) were the highest among the enrolled population followed by pMDI users (n=44, 22.0%), Handihaler users (n=40, 20.0%), and pMDI with spacer users (n=33, 16.5%).

5. Instructor: In our study 100% of the patients were educated by doctors about the use of inhalation devices. Mostly Chest physician (22%) was instructor in PMID with spacer while General Practitioner (22%) was mostly the instructor in DPI single dose. Gupta Vitull et al. 61 found that 71.5% patients were self educated to learn the inhaler technique, 11.6% patients were educated by pharmacist, 10.7% by a hospital staff and only 6.2% patients were actually educated by a doctor. On the other hand, a study by Melani S et al. 62 showed doctors to be the most common source of instruction for inhalation technique (58%), followed by hospital staff (15%) and pharmacists (5%).This difference in educator of inhalation method may be ascribed to the fact that the hospital settings were different for different studies in terms of their functioning, and the present study participants had access to a special inhaler technique training center within the hospital which might had contributed to a higher number of patients being trained by the hospital staff and the doctors.

6. Verbal vs. Demonstration: The present study showed that demonstration method of instruction was more preferred by chest physician than verbal method. While General Practitioner and physicians preferred verbal method of instruction regarding use of device and it was seen that less the mistake done when instruction mode was demonstration than Verbal. There was significant difference between the modes of instruction and the result of steps of inhalation (correct/incorrect), difference was statistically highly significant. P value is <0.00001. This can be compared with the study by Pothirat et al51 where a significant increase in the percentage of improvement in inhalation technique was observed after face-to-face demonstrations and training.

7. Nature of error observed: In the present study it was observed that
out of the 100 subjects, the maximum mistakes committed which was common for all the devices was that 61(61%) subjects had short breath hold after inhaling the drug from device, while 2nd most common mistake was 58 subjects (58%)did not exhale to residual volume before inhaling the drug.

In the PMDI devices with or without spacer ,32 subjects(52.45%) of subjects had short breadth hold while second most common error was not exhaling before inhaling in 31 subjects (50.81%).The third and a major mistake was that 26(42.62%)Subjects didn’t shake the inhaler before use.

This findings can be correlated with the study by Arora et al,58 where most common errors made by the MDI users were “No/Short Breath hold” (45.71%), “Not exhaling to residual volume” (40%). In a recent study from Trivandrum,63 authors found that the major incorrect steps were, not exhaling properly before inhalation (62%), not holding breath correctly (57%), not correctly shaking the inhaler (55%), and not inhaling correctly (17%) for pMDI. In another study by Pothirat et al51 for the pMDI, the steps “breathe out gently to residual volume” and “shake inhaler thoroughly” were most frequently performed incorrectly. On the other hand in a study by Sehajpal R et al48the step at which maximum number of patients committed mistake was exhalation (65.88%) followed by breath holding (45.88%).
But in our study when we consider the PMDI devices without spacer the major issue was of hand breadth coordination where 23 subjects (74.19%) committed error and did not have proper co-ordination. It was followed by short breadth hold and not shaking the inhaler where in both steps 16(51.61%) subjects committed mistakes. Pothirat et al51 has seen that for the pMDI with spacer, the step “breathe in and out through mouthpiece at least three times” was most frequently performed incorrectly.
In our study in DPI devices the maximum mistakes committed which was that 29(74.35%) subjects had short breath hold after inhaling the drug from device, while 2nd most common mistake was 27subjects (64.10%)did not exhale to residual volume before inhaling the drug. Pothirat et al51 has seen that for the Accuhaler, the steps “breathe out gently to residual volume” and “inhale forcefully and deeply” were most frequently performed incorrectly. For the Handihaler, the step “hold breath for at least 10 seconds” was most frequently performed incorrectly. In a study by Arora et al,58 DPI users had “Insufficient acceleration (52.31%), “Not inhaling deeply enough (36.92%)” and “Poor seal around mouth piece (29.23%). In another study by Saxena et al53 the most crucial steps in case of DPI which most of the subjects were found to be performing incorrectly were found to be ‘forceful inhalation through the mouth’ (71.7%), followed by ‘slow exhalation (70.2%), followed by ‘breath holding after inhalation’ (69.1%) and ‘continuing to inhale until lungs were full’ (44.7%).

There are various factors which can influence the patient’s adaptation to the inhalation technique specially the type of instructor who taught the technique which affects the correctness of technique at the preliminary level. It could be due to lack of reinforcement of the technique and periodic observation in subsequent visits that could have ensured that patients maintained adequate technique or it could be deficits in technique of the physicians themselves that could lead them to often choose to not to instruct the patient. In our study, it was seen that less the mistake done when instruction mode was demonstration than Verbal. There was significant difference between the modes of instructions (Verbal vs. Demonstration). So simply asking the patient whether they are using an inhaler properly is not sufficient. As proficiency in good technique tends to decrease over time and patient might introduce errors unknowingly hence repetitive education as well as demonstration is very much necessary.

Conclusion
It was observed that majority of patients were unable to use their inhalers correctly; thus, proper training at each visit should be carried out to get maximum benefit from inhalers.