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1.
Hand Surg Rehabil ; 42(4): 332-336, 2023 09.
Article in English | MEDLINE | ID: mdl-37224960

ABSTRACT

PURPOSE: Motor outcome following a brachial plexus injury is frequently measured to evaluate the success of surgical interventions. We aimed to identify whether the manual muscle testing using the Medical Research Council (MRC) method in adults with C5/6/7 motor weakness was reliable and whether its results correlated with functional recovery. METHODS: Two experienced clinicians examined 30 adults with C5/6/7 weakness following proximal nerve injury. The examination included using the modified MRC to assess motor outcome in the upper limb. Kappa statistics were calculated to evaluate inter-tester reliability. Correlation coefficients was calculated to explore the correlation between the MRC and the Disabilities of the Arm Shoulder and Hand (DASH) score and each EQ5D domain. RESULTS: We found that grades 3-5 of the modified and unmodified MRC motor rating scales have poor inter-rater reliability when assessing C5/6/7 innervated muscles in adults with a proximal nerve injury. The Deltoid Posterior and the Extensor Carpi Radialis Longus were the only muscles (using the modified MRC) to achieve a Kappa over 0.6 indicating substantial reliability. Higher combined MRC scores correlated significantly with a lower DASH and vice versa. Similarly, higher combined scores of MRC correlated significantly with a higher rating of overall health on the EQ5D VAS. CONCLUSIONS: This study demonstrates that the MRC motor rating scale has poor inter-rater reliability when assessing C5/C6/C7 innervated muscles in adults following proximal nerve injury. Other methods of assessing motor outcome following proximal nerve injury need to be considered.


Subject(s)
Brachial Plexus Neuropathies , Brachial Plexus , Adult , Humans , Reproducibility of Results , Brachial Plexus/injuries , Brachial Plexus Neuropathies/surgery , Muscle, Skeletal , Shoulder
2.
Micromachines (Basel) ; 13(4)2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35457855

ABSTRACT

Recent technology advances have led urology to become one of the leading specialities to utilise novel electronic systems to manage urological ailments. Contemporary bladder management strategies such as urinary catheters can provide a solution but leave the user mentally and physically debilitated. The unique properties of modern electronic devices, i.e., flexibility, stretchability, and biocompatibility, have allowed a plethora of new technologies to emerge. Many novel electronic device solutions in urology have been developed for treating impaired bladder disorders. These disorders include overactive bladder (OAB), underactive bladder (UAB) and other-urinary-affecting disorders (OUAD). This paper reviews common causes and conservative treatment strategies for OAB, UAB and OUAD, discussing the challenges and drawbacks of such treatments. Subsequently, this paper gives insight into clinically approved and research-based electronic advances in urology. Advances in this area cover bladder-stimulation and -monitoring devices, robot-assistive surgery, and bladder and sphincter prosthesis. This study aims to introduce the latest advances in electronic solutions for urology, comparing their advantages and disadvantages, and concluding with open problems for future urological device solutions.

3.
Indian J Ophthalmol ; 69(8): 2034-2039, 2021 08.
Article in English | MEDLINE | ID: mdl-34304173

ABSTRACT

Purpose: To determine the causes of visual impairment (VI) and blindness among children in schools for the blind in Myanmar; to identify the avoidable causes of VI and blindness; to provide spectacles, low-vision aids, and ophthalmic treatment where indicated; to provide an update of the 2007 survey performed and identify any major epidemiological changes. Methods: Two hundred and ninety children under 16 years of age from all eight schools for the blind in Myanmar were examined and the data entered into the World Health Organization Prevention of Blindness Examination Record for Childhood Blindness. Results: In total, 271 children (93.4%) were blind (visual acuity [VA] <3/60 in the better eye) and 15 (5.17%) had severe visual impairment (SVI = VA <6/60 to 3/60 in the better eye). Most children had whole globe as the major anatomical site of SVI or blindness (105, 36.6%). The cause was unknown in the majority of these (155, 54.0%). One hundred and twelve children had avoidable causes of blindness and SVI (39.0%). Forty children (13.9%) required an optical device and 10.1% required surgical or medical attention, with a potential for visual improvement through intervention in 3.48%. Conclusion: In all, 39.0% of children had potentially avoidable causes of SVI and blindness with cataracts and measles being the commonest causes. This follow-up survey performed after the first one completed in Myanmar in 2007 demonstrates a change in the major site of abnormality from the cornea to whole globe and a reduction in avoidable blindness but highlights the ongoing burden of measles.


Subject(s)
Vision, Low , Visually Impaired Persons , Blindness/epidemiology , Blindness/etiology , Child , Education, Special , Humans , Myanmar/epidemiology , Schools , Vision Disorders , Vision, Low/epidemiology , Vision, Low/etiology
4.
Healthc Technol Lett ; 3(1): 51-5, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27222733

ABSTRACT

This Letter investigated the efficacy of a decision-support system, designed for respiratory medicine, at predicting asthma exacerbations in a multi-site longitudinal randomised control trial. Adherence to inhaler medication was acquired over 3 months from patients with asthma employing a dose counter and a remote monitoring adherence device which recorded participant's inhaler use: n = 184 (23,656 audio files), 61% women, age (mean ± sd) 49.3 ± 16.4. Data on occurrence of exacerbations was collected at three clinical visits, 1 month apart. The relative risk of an asthma exacerbation for those with good and poor adherence was examined employing a univariate and multivariate modified Poisson regression approach; adjusting for age, gender and body mass index. For all months dose counter adherence was significantly (p < 0.01) higher than remote monitoring adherence. Overall, those with poor adherence had a 1.38 ± 0.34 and 1.42 ± 0.39 (remotely monitored) and 1.25 ± 0.32 and 1.18 ± 0.31 (dose counter) higher relative risk of an exacerbation in model 1 and model 2, respectively. However, this was not found to be statistically significantly different. Remotely monitored adherence holds important clinical information and future research should focus on refining adherence and exacerbation measures. Decision-support systems based on remote monitoring may enhance patient-physician communication, possibly reducing preventable adverse events.

5.
Trials ; 17(1): 226, 2016 May 04.
Article in English | MEDLINE | ID: mdl-27142873

ABSTRACT

BACKGROUND: Poor adherence to inhaled medication may lead to inadequate symptom control in patients with respiratory disease. In practice it can be difficult to identify poor adherence. We designed an acoustic recording device, the INCA® (INhaler Compliance Assessment) device, which, when attached to an inhaler, identifies and records the time and technique of inhaler use, thereby providing objective longitudinal data on an individual's adherence to inhaled medication. This study will test the hypothesis that providing objective, personalised, visual feedback on adherence to patients in combination with a tailored educational intervention in a community pharmacy setting, improves adherence more effectively than education alone. METHODS/DESIGN: The study is a prospective, cluster randomised, parallel-group, multi-site study conducted over 6 months. The study is designed to compare current best practice in care (i.e. routine inhaler technique training) with the use of the INCA® device for respiratory patients in a community pharmacy setting. Pharmacies are the unit of randomisation and on enrolment to the study they will be allocated by the lead researcher to one of the three study groups (intervention, comparator or control groups) using a computer-generated list of random numbers. Given the nature of the intervention neither pharmacists nor participants can be blinded. The intervention group will receive feedback from the acoustic recording device on inhaler technique and adherence three times over a 6-month period along with inhaler technique training at each of these times. The comparator group will also receive training in inhaler use three times over the 6-month study period but no feedback on their habitual performance. The control group will receive usual care (i.e. the safe supply of medicines and advice on their use). The primary outcome is the rate of participant adherence to their inhaled medication, defined as the proportion of correctly taken doses of medication at the correct time relative to the prescribed interval. Secondary outcomes include exacerbation rates and quality of life measures. Differences in the timing and technique of inhaler use as altered by the interventions will also be assessed. Data will be analysed on an intention-to-treat and a per-protocol basis. Sample size has been calculated with reference to comparisons to be made between the intervention and comparator clusters and indicates 75 participants per cluster. With an estimated 10 % loss to follow-up we will be able to show a 20 % difference between the population means of the intervention and comparator groups with a power of 0.8. The Type I error probability associated with the test of the null hypothesis is 0.05. DISCUSSION: This clinical trial will establish whether providing personalised feedback to individuals on their inhaler use improves adherence. It may also be possible to enhance the role of pharmacists in clinical care by identifying patients in whom alteration of either therapy or inhaler device is appropriate. REGISTRATION: ClinicalTrials.gov NCT02203266 .


Subject(s)
Acoustics/instrumentation , Bronchodilator Agents/administration & dosage , Community Pharmacy Services , Feedback, Psychological , Fluticasone-Salmeterol Drug Combination/administration & dosage , Glucocorticoids/administration & dosage , Lung Diseases, Obstructive/drug therapy , Medication Adherence , Nebulizers and Vaporizers , Patient Education as Topic , Administration, Inhalation , Disease Progression , Drug Administration Schedule , Equipment Design , Health Knowledge, Attitudes, Practice , Humans , Ireland , Lung Diseases, Obstructive/diagnosis , Lung Diseases, Obstructive/psychology , Prospective Studies , Quality of Life , Research Design , Time Factors , Treatment Outcome
6.
J Aerosol Med Pulm Drug Deliv ; 29(5): 439-446, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26859629

ABSTRACT

BACKGROUND: The efficacy of drug delivery from inhalers is very much dependent on the user's peak inspiratory flow rate (PIFR). Current methods to measure PIFR in inhalers are based on subjective checklists. There is a lack of methods currently available to objectively remotely monitor PIFR in pressurized metered dose inhalers (pMDIs) and dry powder inhalers (DPIs). In this study, for the first time, non-contact acoustic methods were employed to estimate PIFR through three commonly used inhalers (Diskus™ DPI, Turbuhaler™ DPI, and Evohaler™ pMDI) with the aim of applying these methods to remotely monitor inhaler inhalation technique in future clinical applications. METHODS: Each inhaler was placed inside an airtight container connected to a spirometer to measure PIFR. A high quality microphone was placed 5 cm from the mouthpiece of the inhalers to record inhalation sounds. Over 2000 inhaler inhalation sounds were recorded from 11 healthy participants. A range of temporal and spectral acoustic features from the inhalation sounds were correlated with PIFR. The variation of acoustic features and the repeatability of the inhalation acoustic spectral profile were investigated to further characterize inhaler inhalation sounds and to determine the reliability of acoustics to estimate PIFR. RESULTS: All acoustic features were significantly correlated with PIFR (p < 0.001). The mean power of the inhalation sound generated the most consistent correlation across all inhalers [R2 = 0.77 (Diskus™), R2 = 0.7 (Turbuhaler™), R2 = 0.75 (Evohaler™)]. Acoustic features generated low variation and the spectral profile of inhalation sounds was repeatable regardless of flow rate, suggesting that acoustic methods are a reliable method of estimating PIFR. CONCLUSIONS: The methods presented in this study may be employed in a wearable monitoring device in future applications to measure inhaler PIFR. Objective monitoring of PIFR in inhalers may help patients improve their inhaler inhalation technique and therefore may be of significant clinical benefit to both patients and clinicians.

7.
BMJ Open ; 6(1): e009350, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26729384

ABSTRACT

INTRODUCTION: In clinical practice, it is difficult to distinguish between patients with refractory asthma from those with poorly controlled asthma, where symptoms persist due to poor adherence, inadequate inhaler technique or comorbid diseases. We designed an audio recording device which, when attached to an inhaler, objectively identifies the time and technique of inhaler use, thereby assessing both aspects of adherence. This study will test the hypothesis that feedback on these two aspects of adherence when passed on to patients improves adherence and helps clinicians distinguish refractory from difficult-to-control asthma. METHODS: This is a single, blind, prospective, randomised, clinical trial performed at 5 research centres. Patients with partially controlled or uncontrolled severe asthma who have also had at least one severe asthma exacerbation in the prior year are eligible to participate. The effect of two types of nurse-delivered education interventions to promote adherence and inhaler technique will be assessed. The active group will receive feedback on their inhaler technique and adherence from the new device over a 3-month period. The control group will also receive training in inhaler technique and strategies to promote adherence, but no feedback from the device. The primary outcome is the difference in actual adherence, a measure that incorporates time and technique of inhaler use between groups at the end of the third month. Secondary outcomes include the number of patients who remain refractory despite good adherence, and differences in the components of adherence after the intervention. Data will be analysed on an intention-to-treat and a per-protocol basis. The sample size is 220 subjects (110 in each group), and loss to follow-up is estimated at 10% which will allow results to show a 10% difference (0.8 power) in adherence between group means with a type I error probability of 0.05. TRIAL REGISTRATION NUMBER: NCT01529697; Pre-results.


Subject(s)
Anti-Asthmatic Agents/administration & dosage , Feedback , Medication Adherence , Nebulizers and Vaporizers , Administration, Inhalation , Anti-Asthmatic Agents/therapeutic use , Asthma , Electrical Equipment and Supplies , Electronics , Humans , Prospective Studies , Research Design , Severity of Illness Index , Single-Blind Method
8.
J Aerosol Med Pulm Drug Deliv ; 28(4): 247-53, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25393346

ABSTRACT

BACKGROUND: Dry powder inhaler (DPI) users frequently exhale into their inhaler mouthpiece before the inhalation step. This error in technique compromises the integrity of the drug and results in poor bronchodilation. This study investigated the effect of four exhalation factors (exhalation flow rate, distance from mouth to inhaler, exhalation duration, and relative air humidity) on dry powder dose delivery. Given that acoustic energy can be related to the factors associated with exhalation sounds, we then aimed to develop a method of identifying and quantifying this critical inhaler technique error using acoustic based methods. METHODS: An in vitro test rig was developed to simulate this critical error. The effect of the four factors on subsequent drug delivery were investigated using multivariate regression models. In a further study we then used an acoustic monitoring device to unobtrusively record the sounds 22 asthmatic patients made whilst using a Diskus(™) DPI. Acoustic energy was employed to automatically detect and analyze exhalation events in the audio files. RESULTS: All exhalation factors had a statistically significant effect on drug delivery (p<0.05); distance from the inhaler mouthpiece had the largest effect size. Humid air exhalations were found to reduce the fine particle fraction (FPF) compared to dry air. In a dataset of 110 audio files from 22 asthmatic patients, the acoustic method detected exhalations with an accuracy of 89.1%. We were able to classify exhalations occurring 5 cm or less in the direction of the inhaler mouthpiece or recording device with a sensitivity of 72.2% and specificity of 85.7%. CONCLUSIONS: Exhaling into a DPI has a significant detrimental effect. Acoustic based methods can be employed to objectively detect and analyze exhalations during inhaler use, thus providing a method of remotely monitoring inhaler technique and providing personalized inhaler technique feedback.


Subject(s)
Acoustics , Asthma/drug therapy , Bronchodilator Agents/administration & dosage , Drug Delivery Systems/instrumentation , Dry Powder Inhalers , Exhalation , Fluticasone-Salmeterol Drug Combination/administration & dosage , Inhalation , Administration, Inhalation , Aerosols , Air , Algorithms , Asthma/physiopathology , Bronchodilator Agents/chemistry , Case-Control Studies , Equipment Design , Fluticasone-Salmeterol Drug Combination/chemistry , Humans , Humidity , Lung/drug effects , Lung/physiopathology , Multivariate Analysis , Powders , Regression Analysis , Respiratory Sounds , Signal Processing, Computer-Assisted , Sound Spectrography , Time Factors
9.
Article in English | MEDLINE | ID: mdl-26736734

ABSTRACT

Inhalers are hand-held devices used to treat chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). Medication is delivered from an inhaler to the user through an inhalation maneuver. It is unclear whether gender and anthropometric features such as age, height, weight and body mass index (BMI) influence the acoustic properties of inspiratory inhaler sounds and peak inspiratory flow rate (PIFR) in inhalers. In this study, healthy male (n=9) and female (n=7) participants were asked to inhale at an inspiratory flow rate (IFR) of 60 L/min in four commonly used inhalers (Turbuhaler(™), Diskus(™), Ellipta(™) and Evohaler(™)). Ambient inspiratory sounds were recorded from the mouthpiece of each inhaler and over the trachea of each participant. Each participant's PIFR was also recorded for each of the four inhalers. Results showed that gender and anthropometric features have the potential to influence the spectral properties of ambient and tracheal inspiratory inhaler sounds. It was also observed that males achieved statistically significantly higher PIFRs in each inhaler in comparison to females (p<;0.05). Acoustic features were found to be significantly different across inhalers suggesting that acoustic features are modulated by the inhaler design and its internal resistance to airflow.


Subject(s)
Asthma/physiopathology , Nebulizers and Vaporizers , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Sounds/physiopathology , Adult , Anthropometry , Asthma/drug therapy , Female , Humans , Male , Pulmonary Disease, Chronic Obstructive/drug therapy , Sex Factors , Tape Recording
10.
PLoS One ; 9(6): e98701, 2014.
Article in English | MEDLINE | ID: mdl-24905012

ABSTRACT

RATIONALE: Poor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use. OBJECTIVES: This paper introduces a device developed to create time stamped acoustic recordings of an individual's inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence. FINDINGS: The technology was validated by showing that the doses taken matched the number of audio recordings (r2 = 0.94, p<0.01). To demonstrate that audio analysis of inhaler use gives objective information, in vitro studies were performed. These showed that acoustic profiles of inhalations correlated with the peak inspiratory flow rate (r2 = 0.97, p<0.01), and that the acoustic energy of exhalations into the inhaler was related to the amount of drug removed. Despite training, 16% of participants exhaled into the mouthpiece after priming, in >20% of their inhaler events. Repeated training reduced this to 7% of participants (p = 0.03). When time of use was considered, there was no evidence of a relationship between adherence and changes in AQLQ (r2 = 0.2) or PEFR (r2 = 0.2). Combining time and technique the rate of adherence was related to changes in AQLQ (r2 = 0.53, p = 0.01) and PEFR (r2 = 0.29, p = 0.01). CONCLUSIONS: This study presents a novel method to objectively assess how errors in both time and technique of inhaler use impact on clinical outcomes. TRIAL REGISTRATION: EudraCT 2011-004149-42.


Subject(s)
Acoustics/instrumentation , Nebulizers and Vaporizers/statistics & numerical data , Patient Compliance , Adolescent , Adult , Aged , Aged, 80 and over , Electronic Data Processing , Female , Humans , Male , Middle Aged , Time Factors , Young Adult
11.
Pharm Res ; 31(10): 2735-47, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24867420

ABSTRACT

PURPOSE: Some patients are unable to generate the peak inspiratory flow rate (PIFR) necessary to de-agglomerate drug particles from dry powder inhalers (DPIs). In this study we tested the hypothesis that the acoustic parameters of an inhalation are related to the PIFR and hence reflect drug delivery. METHODS: A sensitivity analysis of the relationship of the acoustics of inhalation to simultaneously recorded airflow, in a cohort of volunteers (n = 92) was performed. The Next Generation Impactor (NGI) was used to assess in vitro drug delivery from salmeterol/fluticasone and salbutamol Diskus™ DPIs. Fine particle fraction, FPF, (<5 µm) was measured at 30-90 l/min for 2-6 s and correlated with acoustically determined flow rate (IFRc). In pharmacokinetic studies using a salbutamol (200 µg) Diskus™, volunteers inhaled either at maximal or minimal effort on separate days. RESULTS: PIFRc was correlated with spirometrically determined values (R (2) = 0.88). In in vitro studies, FPF increased as both flow rate and inhalation duration increased for the salmeterol/fluticasone Diskus™ (Adjusted R (2) = 0.95) and was proportional to flow rate only for the salbutamol Diskus™ (Adjusted R (2) = 0.71). In pharmacokinetic studies, blood salbutamol levels measured at 20 min were significantly lower when PIFRc was less than 60 l/min, p < 0.0001. CONCLUSION: Acoustically-determined PIFR is a suitable method for estimating drug delivery and for monitoring inhalation technique over time.


Subject(s)
Acoustics/instrumentation , Drug Delivery Systems/instrumentation , Dry Powder Inhalers , Inhalation/physiology , Inspiratory Capacity/physiology , Administration, Inhalation , Aerosols , Albuterol/administration & dosage , Albuterol/analogs & derivatives , Albuterol/blood , Albuterol/pharmacokinetics , Androstadienes/administration & dosage , Androstadienes/blood , Androstadienes/pharmacokinetics , Drug Combinations , Equipment Design , Fluticasone-Salmeterol Drug Combination , Humans
12.
Article in English | MEDLINE | ID: mdl-25571019

ABSTRACT

Chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) affect over 400 million people and are incurable. The pressurized metered dose inhaler (pMDI) has been the most popular inhaler device in inhaled therapy in recent times. However the pMDIs require good coordination between inhaling and actuating the inhaler to deliver the aerosolized drug most effectively. Poor coordination can greatly reduce the amount of drug delivered to a patient and therefore reducing the control of respiratory disease symptoms. Acoustic methods have been recently employed to monitor inhaler technique quite effectively. This study employs a noninvasive acoustic method to detect actuation sounds in a portable monitoring device. A total of 158 actuation sounds were obtained from a group of healthy subjects (n=5) and subjects suffering from respiratory diseases (n=15). The developed algorithm generated an overall accuracy of 99.7% demonstrating that this method may have clinical potential to monitor pMDI actuation coordination. The informative feedback from this method may also be employed in clinical training to highlight patient actuation technique.


Subject(s)
Metered Dose Inhalers , Administration, Inhalation , Adult , Aged , Aged, 80 and over , Asthma/drug therapy , Female , Humans , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/drug therapy , Sound , Young Adult
13.
IEEE J Transl Eng Health Med ; 2: 2700210, 2014.
Article in English | MEDLINE | ID: mdl-27170883

ABSTRACT

Inhalers are devices which deliver medication to the airways in the treatment of chronic respiratory diseases. When used correctly inhalers relieve and improve patients' symptoms. However, adherence to inhaler medication has been demonstrated to be poor, leading to reduced clinical outcomes, wasted medication, and higher healthcare costs. There is a clinical need for a system that can accurately monitor inhaler adherence as currently no method exists to evaluate how patients use their inhalers between clinic visits. This paper presents a method of automatically evaluating inhaler adherence through acoustic analysis of inhaler sounds. An acoustic monitoring device was employed to record the sounds patients produce while using a Diskus dry powder inhaler, in addition to the time and date patients use the inhaler. An algorithm was designed and developed to automatically detect inhaler events from the audio signals and provide feedback regarding patient adherence. The algorithm was evaluated on 407 audio files obtained from 12 community dwelling asthmatic patients. Results of the automatic classification were compared against two expert human raters. For patient data for whom the human raters Cohen's kappa agreement score was [Formula: see text], results indicated that the algorithm's accuracy was 83% in determining the correct inhaler technique score compared with the raters. This paper has several clinical implications as it demonstrates the feasibility of using acoustics to objectively monitor patient inhaler adherence and provide real-time personalized medical care for a chronic respiratory illness.

14.
Article in English | MEDLINE | ID: mdl-24111322

ABSTRACT

Morbidity and mortality rates of chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) are rising. There is a strong requirement for more effective management of these chronic diseases. Dry powder inhalers (DPIs) are one kind of devices currently employed to deliver medication aimed at controlling asthma and COPD symptoms. Despite their proven effectiveness when used correctly, some patients are unable to reach the inspiratory flow rate required to remove medication from the breath actuated devices and as a result, the medication does not reach the airways. This study employs an acoustic recording device, attached to a common DPI to record the audio signals of simulated inhalations. A rotameter was used to measure the flow rate through the inhaler while a milligram weighing scale was used to measure the amount of drug removed from each simulated inhalation. It was found that a strong correlation existed (R(2)>0.96) when average power, median amplitude, root mean square and mean absolute deviation were used to predict peak inspiratory flow rate. At a flow of 30 L/Min (mean absolute deviation=0.0049), it was found that 77% of the total emitted dose was removed from the inhaler. Results indicate that acoustic measurements may be used in the prediction of inspiratory flow rate and quantity of medication removed from an inhaler.


Subject(s)
Acoustics/instrumentation , Dry Powder Inhalers/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Administration, Inhalation , Equipment Design
15.
Article in English | MEDLINE | ID: mdl-24109939

ABSTRACT

Chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) affect millions of people worldwide. Inhalers are devices utilized to deliver medication in small doses directly to the airways in the treatment of asthma and COPD. Despite the proven effectiveness of inhaler medication in controlling symptoms, many patients suffer from technique errors leading to decreased levels of medication efficacy. This study employs a recording device attached to a commonly used dry powder inhaler (DPI) to obtain the acoustic signals of patients taking their inhaler medication. The audio files provide information on how a patient uses their inhaler over a period of one month. Manually listening to such a large quantity of audio files would be a time consuming and monotonous process and therefore an algorithm that could automatically carry out this task would be of great benefit. An algorithm was thus designed and developed to detect inhalation, exhalation and blister events in the audio signals, analyze the quantity of each event, the order in which the events took place and finally provide a score on the overall performance. The algorithm was tested on a dataset of 185 audio files obtained from five community dwelling asthmatic patients in real world environments. Evaluation of the algorithm on this dataset revealed that it had an accuracy of 92.8% in deciding the correct technique score compared to manual detection methods.


Subject(s)
Algorithms , Asthma/prevention & control , Nebulizers and Vaporizers , Pulmonary Disease, Chronic Obstructive/prevention & control , Acoustics , Adult , Aged , Automation , Female , Humans , Male , Middle Aged , Signal Processing, Computer-Assisted , Tape Recording
16.
Physiol Meas ; 34(8): 903-14, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23892977

ABSTRACT

Inhalers are devices employed to deliver medication to the airways in the treatment of respiratory diseases such as asthma and chronic obstructive pulmonary disease. A dry powder inhaler (DPI) is a breath actuated inhaler that delivers medication in dry powder form. When used correctly, DPIs improve patients' clinical outcomes. However, some patients are unable to reach the peak inspiratory flow rate (PIFR) necessary to fully extract the medication. Presently clinicians have no reliable method of objectively measuring PIFR in inhalers. In this study, we propose a novel method of estimating PIFR and also the inspiratory capacity (IC) of patients' inhalations from a commonly used DPI, using acoustic measurements. With a recording device, the acoustic signal of 15 healthy subjects using a DPI over a range of varying PIFR and IC values was obtained. Temporal and spectral signal analysis revealed that the inhalation signal contains sufficient information that can be employed to estimate PIFR and IC. It was found that the average power (Pave) in the frequency band 300-600 Hz had the strongest correlation with PIFR (R(2) = 0.9079), while the power in the same frequency band was also highly correlated with IC (R(2) = 0.9245). This study has several clinical implications as it demonstrates the feasibility of using acoustics to objectively monitor inhaler use.


Subject(s)
Acoustics/instrumentation , Inhalation/physiology , Nebulizers and Vaporizers , Rheology/instrumentation , Adolescent , Adult , Demography , Humans , Inspiratory Capacity/physiology , Spirometry , Young Adult
17.
Article in English | MEDLINE | ID: mdl-23366456

ABSTRACT

Asthma is chronic airways disease characterized by recurrent attacks of breathlessness and wheezing. Adherence to medication regimes is a common failing for asthmatic patients and there exists a requirement to monitor such patients' adherence. The detection of inhalations from recordings of inhaler use can provide empirical evidence about patients' adherence to their asthma medication regime. Manually listening to recordings of inhaler use is a tedious and time consuming process and thus an algorithm which can automatically and accurately carry out this task would be of great value. This study employs a recording device attached to a commonly used dry powder inhaler to record the acoustic signals of patients taking their prescribed medication. An algorithm was developed to automatically detect and accurately demarcate inhalations from the acoustic signals. This algorithm was tested on a dataset of 255 separate recordings of inhaler use in real world environments. The dataset was obtained from 12 asthma outpatients who attended a respiratory clinic over a three month period. Evaluation of the algorithm on this dataset achieved sensitivity of 95%, specificity of 94% and an accuracy of 89% in detecting inhalations compared to manual inhalation detection.


Subject(s)
Anti-Asthmatic Agents/administration & dosage , Asthma/drug therapy , Administration, Inhalation , Adult , Aged , Anti-Asthmatic Agents/therapeutic use , Dry Powder Inhalers , Female , Humans , Male , Middle Aged , Patient Compliance , Young Adult
18.
Ophthalmic Epidemiol ; 17(4): 225-33, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20642345

ABSTRACT

PURPOSE: To identify the causes of blindness and severe visual impairment (BL/SVI) in children attending four schools for the blind in Cambodia and to provide spectacles, low vision aids, orientation and mobility training and ophthalmic treatment. METHODS: Children < 16 years of age were recruited from all 4 schools for the blind in Cambodia. Causes of visual impairment and blindness were determined and categorized using World Health Organization methods. RESULTS: Of the 95 children examined, 54.7% were blind (BL) and 10.5% were severely visually impaired (SVI). The major anatomical site of BL/SVI was the lens in 27.4%, cornea in 25.8%, retina in 21% and whole globe in 17.7%. The major underlying etiologies of BL/SVI were hereditary factors (mainly cataract and retinal dystrophies) in 45.2%, undetermined/unknown (mainly microphthalmia and anterior segment dysgenesis) in 38.7% and childhood factors in 11.3%. Avoidable causes of BL/SVI accounted for 50% of the cases; 12.9% of the total were preventable with measles being the commonest cause (8.1% of the total); 37.1% were treatable with cataracts and glaucoma being the commonest causes (22.6% and 4.8% respectively). More than 35% of children required an optical device and 27.4% had potential for visual improvement with intervention. CONCLUSION: Half of the BL/SVI causes were potentially avoidable. The data support the need for increased coverage of measles immunization. There is also a need to develop specialized pediatric ophthalmic services for the management of surgically remediable conditions, to provide optometric, low vision and orientation and mobility services. Genetic risk counseling services also may be considered.


Subject(s)
Blindness/epidemiology , Education, Special/statistics & numerical data , Vision, Low/epidemiology , Visually Impaired Persons/statistics & numerical data , Adolescent , Blindness/etiology , Cambodia/epidemiology , Child , Child, Preschool , Eyeglasses , Female , Health Surveys , Humans , Male , Schools , Sensory Aids , Vision, Low/etiology
19.
Ophthalmic Epidemiol ; 16(6): 370-7, 2009.
Article in English | MEDLINE | ID: mdl-19995202

ABSTRACT

PURPOSE: To determine the causes of visual impairment and blindness amongst children in schools for the blind in Myanmar; to identify the avoidable causes of visual impairment and blindness; and to provide spectacles, low vision aids, orientation and mobility training and ophthalmic treatment where indicated. METHODS: Two hundred and eight children under 16 years of age from all 7 schools for the blind in Myanmar were examined and the data entered into the World Health Organization Prevention of Blindness Examination Record for Childhood Blindness (WHO/PBL ERCB). RESULTS: One hundred and ninety nine children (95.7%) were blind (BL = Visual Acuity [VA] < 3/60 in the better eye) and 3 had severe visual impairment (SVI = VA < 6/60 to 3/60 in the better eye). Most children had corneal abnormalities as the major anatomical site of SVI/BL (100, 49.5%), however the cause of SVI/BL was unknown in the majority (88, 43.6%). Measles keratitis was the commonest identifiable cause (17.4%) and 88 children had avoidable causes of SVI/BL (43.6%). Nearly 16% of children required an optical device and 24.2% required medical attention, with a potential for visual improvement through intervention in 15.8%. CONCLUSION: Nearly half of the children in schools for the blind in Myanmar had potentially avoidable causes of SVI/BL. With measles being both the commonest identifiable and commonest avoidable cause, the data supports the need for a measles immunization campaign. There is also a need for a dedicated pediatric eye care center with regular ophthalmology visits to the schools, and improved optometric, low vision and orientation and mobility services in Myanmar.


Subject(s)
Blindness/epidemiology , Education, Special/statistics & numerical data , Health Surveys , Schools/statistics & numerical data , Vision, Low/epidemiology , Visually Impaired Persons/statistics & numerical data , Adolescent , Blindness/etiology , Blindness/therapy , Child , Eyeglasses , Female , Humans , Male , Myanmar/epidemiology , Sensory Aids , Vision, Low/etiology , Vision, Low/therapy , Visual Acuity
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