Peak Inspiratory Flow Meter Research Articles

Exploration of quality criteria for the detection of peak inspiratory flow under different resistance conditions.

At present, robust quality criteria and methods for the assessment of Peak inspiratory flow meter performance are lacking. A standard flow-volume simulator for quality control analyses of an inhalation assessment device was utilized with different simulated resistance levels in order to propose a quality testing method and associated standard for this device type. A standard flow-volume simulator was utilized to assess the performance of an In-Check DIAL® (Device I) and an intelligent inhalation assessment device (Device P) at a fixed volume and flow rate. Indices used to evaluate these two instruments included repeatability, accuracy, linearity, and impedance. Both devices exhibited good repeatability (<± 3 L/min). The difference between test results and standard simulator values for Device P was less than ± 5 L/min at resistance level R1 but higher than ± 5 L/min at resistance levels R2-5, while Device I were greater than 5 L/min at all resistance levels. The relative error for Device P was <± 10% at resistance levels R1, R2, and R4, but > 10% at resistance levels R3 and R5. The relative error values for Device I at all five resistance levels were > 10%. Device P passed the linearity test at the R2 resistance level, while Device I partially passed the linearity test at all five resistance levels. Standard monitoring methods and standards provide a valuable approach to the more reliable clinical assessment and application of these instruments.

Comparative Analysis of Peak Inspiratory Flow Rate at Discharge and Three-month Follow-up in Severe Acute Exacerbation of COPD Patients using Metered Dose Inhalers versus Dry Powder Inhalers: A Prospective Observational Study

Introduction: Patients discharged following hospitalisation for Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD) are prescribed Metered Dose Inhalers (MDI), Dry Powder Inhalers (DPI), or nebulisers. Drug dispersion from the inhaler and deposition in the lung depends on Peak Inspiratory Flow Rate (PIFR) among other factors. A low PIFR results in suboptimal drug delivery and is a risk factor for readmission. Aim: To estimate PIFR at discharge following AECOPD, assess the type of inhalers prescribed at discharge, and estimate the mean change in PIFR at three months follow-up in patients using MDI and DPI. Materials and Methods: A prospective observational study was conducted at a tertiary care hospital, Goa Medical College, Goa, India on 138 patients over 15 months from November 2018 to February 2020. A sample size of 138 was calculated, and the study duration was 15 months. Patients admitted with AECOPD were enrolled in the study after obtaining informed consent. At discharge, baseline characteristics and co-morbidities were recorded, and PIFR was measured using an in-check dial peak inspiratory flow meter without resistance. Inhalers prescribed by the treating physician were verified and checked for errors. PIFR was measured at three months of follow-up. Optimal PIFR was defined as PIFR of ≥60 L/min. Statistical analysis was performed using the Statistical Package for Social Science Programs (SPSS) version 24.0 (IBM Corp, SPSS Inc, Chicago, IL). A paired t-test assessed the change in PIFR at discharge and three months follow-up, and Pearson’s correlation test was used to assess the correlation between continuous variables. Results: Total 138 were enrolled with a mean age of 69.8±7.5 years, 87 (63%) were males. The mean PIFR at discharge was 58.9±24.7 L/min. 85 (61.6%) had suboptimal PIFR and were older {71.9±7.8 versus 66.3±5.6, p-value=0.01}. A total of 59 (69.4%) with suboptimal PIFR received MDI. At three months, the suboptimal PIFR group receiving MDI showed a mean change in PIFR of 18.6±7.7, p-value&lt;0.001 while with DPI mean change was -3.8±6.3, p-value=0.005. Conclusion: 61.6% had suboptimal PIFR at discharge following hospitalisation with AECOPD. Patients with suboptimal PIFR receiving MDI showed improvement in PIFR at three months, while those with suboptimal PIFR using DPI showed significant deterioration. Identifying patients with suboptimal PIFR will aid appropriate prescription of inhaler devices.

Verifying Efficacy of Self-Inhalation Training for Velopharyngeal Dysfunction

Velopharyngeal closure in healthy adults during different tasksObjective: Velopharyngeal dysfunction causes not only resonance problems (so-called “hypernasality”) but also dysphagia, particularly in the elderly. In our previous study, we developed a new inhaling training method to objectively improve velopharyngeal function using the measurement of peak inspiratory flow (PIF) rate, which was effective in all patients. In this study, we clarify the degree of velopharyngeal closure to determine the efficacy of our training to improve the closure mechanism. Methods: Three healthy volunteers performed tasks in a magnetic resonance imaging (MRI) gantry in the supine position. To confirm velopharyngeal function, volunteers were first asked to distinguish the difference in the velum position between the production of a nonnasal (sustained phonation /shi:/) and a nasal (sustained phonation /n:/) sound. They were then asked to inhale forcefully through the mouth from an empty 500-mL plastic bottle. For comparison, volunteers performed exhaling forcefully, then inhaling and exhaling softly, through a straw. Each task was performed for 30 s, and the MRI images were obtained in sagittal sections. Results: Inhaling forcefully from an empty plastic bottle created the strongest velopharyngeal closure between the posterior surface of the velum (soft palate) and the posterior pharyngeal wall in all volunteers. Conclusion: The results of our MRI study supported our training method. Using inhalation through a PIF meter or from a plastic bottle to create resistance strengthens particularly the levator veli palatini muscle for velopharyngeal closure, which may be useful in patients with other acquired velopharyngeal dysfunctions including physiological aging. Also, anyone anywhere can train with plastic bottles.

Peak inspiratory flow as predictor for tracheotomy

ObjectivesQuantitative evaluation of upper airway obstruction cannot be commonly performed under acute dyspnea, especially in head and neck cancer (HNC); the decision whether or not to perform airway control surgery may be difficult to reach. Peak inspiratory flow (PIF) has been previously demonstrated to be a useful tool to decide on decannulation after HNC surgery. The aim of the present study was to assess the role of PIF as a standardized non-invasive tool in quantifying severe inspiratory dyspnea requiring emergency tracheostomy. Materials and methodsA single-center prospective observational pilot study analyzed PIF measurements in 22 patients exhibiting acute dyspnea due to upper airway obstruction. Main outcome measuresThe decision whether or not to perform tracheotomy was taken prior to PIF measurement. PIF was measured with a hand-held PIF meter (In-Check method), and laryngeal fiberoscopy was then performed. Obstruction severity was defined by PIF values. ResultsPIF could be measured prior to tracheotomy (imminent in 21 cases, postponed in 1) in all cases. PIF values below 53.1 L/min (i.e., 18.3% of theoretic value) correlated with necessity for emergency tracheotomy. This threshold is concordant with that previously found for the feasibility of decannulation (60L/min). ConclusionsPIF is a non-invasive quantitative parameter assessing severity of upper airway obstruction, that may be helpful in decision-making for tracheostomy. Testing is simple, quick and reproducible.

Peak inspiratory flow is a simple means of predicting decannulation success following head and neck cancer surgery: a prospective study of fifty-six patients.

Temporary tracheotomies are commonly performed in head and neck cancer surgery. The aim of this study was to propose a minimum peak inspiratory flow (PIF) as a standardized simple tool for successful decannulation after surgery. Prospective review between January 2011 and June 2013 in a university teaching hospital. Fifty-six patients after head and neck cancer surgery requiring tracheotomies were included. Decannulation failure was defined as the need to recannulate patients within 24 hours. PIF values did not influence the decisions to decannulate or recannulate. Pre- and postdecannulation PIF values, measured with a handheld PIF meter (In-Check Dial), were registered until definitive decannulation. A total of 67 decannulation attempts were performed, with 47 positive and nine negative decannulations at the first attempt. Of the latter, seven were positive at the second attempt and two at the third. All patients were decannulated (mean, 6.3 days). PIF values of 40 L/min appear to be the threshold with the best sensitivity (90%) and specificity (95%) for predicting decannulation success. There was a significant difference (P < .001) between mean PIF in the positive (86 L/min) and negative (20 L/min) decannulation groups and between mean PIF values with (77 L/min) and without cannula (100 L/min). PIF ≥40 L/min with cannula (>60 L/min without) using the In-Check Dial oral method is a threshold associated with decannulation success. PIF is a simple quantitative parameter for evaluating the upper airway, aiding the decision to decannulate safely. 4.

Reduced Peak Inspiratory Effort through the Diskus?? and the Turbuhaler?? due to Mishandling is??Common in Clinical Practice

A minimum peak inspiratory flow (PIF) through dry powder inhalers (DPIs) is required for effective drug delivery to the lungs. Some patients are unable to generate the minimally effective PIF through the DPI. However, little information is available about the 'real life' prevalence of reduced peak inspiratory effort through the Diskus((R)) and the Turbuhaler((R)) as a result of mishandling We investigated peak inhalation effort through the Diskus((R)) and the Turbuhaler((R)) by both direct observation and the In-Check Dial((R)), a portable PIF meter, in a large sample of patients consecutively referred to our laboratory who were familiar with these devices. Patients with reduced peak inspiratory effort repeated the PIF measurement after a session of instruction on the need for more forceful effort through the device. We studied 644 patients (mean age 62 years, 42% female). Of these, 62% had chronic obstructive pulmonary disease and 35% had asthma. The mean baseline forced expiratory volume in 1 second was 53% of predicted. 502 patients were using the Diskus((R)) and 185 the Turbuhaler((R)). Overall, 106 patients (16.5%) showed weak inhalation by direct observation at baseline. Of 44 subjects with weak inhalation through the Turbuhaler((R)), 34 (77%) demonstrated a PIF <30 L/min. Post-counselling, only four patients did not achieve a PIF of at least 30 L/min (p < 0.01). Of 62 subjects with weak inhalation through the Diskus((R)), 37 (60%) had a PIF <30 L/min. Post-counselling, all these subjects achieved a PIF of at least 30 L/min (p < 0.001). A significant number of patients show a reduced peak inspiratory effort through the Diskus((R)) and the Turbuhaler((R)) in real life. Our results indicate that the cause of this deficiency is often mishandling of the device because, after a brief session of instruction on the need for more forceful inhalation, most patients obtained an acceptable PIF rate. A PIF meter may identify patients with inadequately weak inhalation and offer useful feedback for obtaining the best inspiratory effort.

Measurement of peak inspiratory flow with in-check dial device to simulate low-resistance (Diskus) and high-resistance (Turbohaler) dry powder inhalers in children with asthma

Drug delivery and lung deposition from a dry powder inhaler (DPI) are dependent on the peak inspiratory flow (PIF) through the DPI. Therefore, when prescribing a DPI, it is important to know whether a child is able to generate sufficient PIF through a particular device. Using a PIF meter (In-Check Dial) that mimics the internal resistance of DPIs, two commonly used devices (high-resistance Turbohaler (TH) and low-resistance Diskus (DK)) determined the PIF generated by asthmatic children through each of them. Two hundred and twenty-three children were studied, of whom 100 (mean age, 9.1 +/- 3.0 years; range, 3-15 years) were experienced with the use of a DPI (>1 month of regular DPI use), and 123 (mean, 5.5 +/- 1.9 years; range, 3-9 years) were inexperienced (no previous DPI use). All of the experienced patients generated more than 30 l/min through both devices, but a PIF of 60 l/min through the TH was obtained by only 68 (68%) of them. The age above which a minimal PIF of 30 l/min (for DK) or 60 l/min (for TH) could be achieved in new DPI users (inexperienced) was 4 years and 9 years, respectively. Even among experienced patients, many young children may not generate optimal PIFs through high-resistance DPIs. When DPI treatment is considered for young children, some devices may be successfully introduced at a younger age. It may thus be important to measure PIF in children who use a DPI or in whom DPI use is contemplated. This evaluation can be easily undertaken in the clinic with the In-Check Dial device.

Peak inspiratory flow through Diskus and Turbuhaler, measured by means of a peak inspiratory flow meter (In-Check DIAL ®)

With a handheld peak inspiratory flow (PIF) meter (In-Check DIAL ®), the internal resistance of the Diskus ® (DKR) and the Turbuhaler ® (THR) can be simulated by means of calibrated resistances. This study investigated whether patients with asthma or chronic obstructive pulmonary disease could generate a PIF which is optimal for the Diskus (DK) (30 l/min) and the Turbuhaler (TH) (60 l/min). Peak expiratory flow (PEF) and maximal inspiratory pressure (MIP) were also assessed. All 50 patients (30 males, mean age 56.9) achieved the required flow of 30 l/min with the DKR, while six patients (five females) could not generate the optimal flow of 60 l/min via the THR. Analysis showed that MIP was an independent predictor of an adequate PIF through the THR. During the study, eight patients were treated for an exacerbation of which four could not generate an adequate PIF via the THR. Analysis showed that the female gender and an exacerbation appeared to be independent predictors of the inability to generate an adequate PIF via the THR. Twelve per cent of patients (25% of females) could not generate the optimal inspiratory flow via the THR. When in doubt whether the patient can generate an adequate inspiration, measurement with the In-Check DIAL ® is recommended.

Fluticasone propionate nasal spray is more effective and has a faster onset of action than placebo in treatment of rhinitis medicamentosa

Controversy still exists about the treatment of rhinitis medicamentosa and treatment has never been objectively evaluated. To study the effect of fluticasone propionate aqueous nasal spray compared to placebo nasal spray in the treatment of rhinitis medicamentosa. A parallel randomized, double-blind study was conducted to evaluate the treatment of rhinitis medicamentosa. Two groups containing 10 patients with rhinitis medicamentosa in each group stopped their overuse of nasal vasoconstrictor spray immediately and were treated with either fluticasone propionate nasal spray once daily 200 micrograms, or placebo nasal spray for 14 days. The nasal mucosal swelling was recorded with rhinostereometry, acoustic rhinometry and a peak inspiratory flow meter. Nasal stuffiness was estimated on a visual analogue scale in the morning and in the evening of each day. The mucosal swelling decreased after 7 and 14 days of treatment with fluticasone propionate as well as placebo, but the reduction was significantly greater after treatment with fluticasone propionate. The symptom scores for nasal stuffiness showed a marked reduction during the treatment period in both groups, but there was a faster onset of symptom reduction after treatment with fluticasone propionate. Fluticasone propionate is more effective and has a faster onset of action than placebo in the treatment of rhinitis medicamentosa. An adequate treatment of these patients consists of a combination of vasoconstrictor withdrawal and a topical corticosteroid to alleviate the withdrawal process.