Inspiratory Flow Measurements Research Articles

Dry-powder inhaler use in primary school-aged children with asthma: a systematic review.

Asthma is the most common chronic disease among children. Dry-powder inhalers (DPIs) are effective for medication delivery in adults and adolescents, and provide a lower environmental footprint and more portability than a metered dose inhaler (MDI) with a spacer. They require a specific technique, and it is necessary to ascertain whether they can be used in younger age groups. We aimed to assess evidence regarding whether primary school-aged (5-11 years) children can use DPIs with adequate technique during both stable and acute asthma. Ovid MEDLINE, Embase and PubMed were searched for studies assessing DPI use among children aged 5-11 years with asthma or wheeze. Results of studies were synthesised by study design and outcome measure. 38 studies were identified for analysis. These were analysed in three groups: 1) 25 studies assessing children's ability to use DPIs by peak inspiratory flow measurement, 2) 10 studies assessing children's ability to use DPIs by physician assessment, and 3) three studies measuring the efficacy of DPIs compared with the gold standard (MDI with spacer). Five studies included children during acute exacerbations. The majority of primary school-aged children have the ability to use a DPI with adequate training, support and practice. Some younger children may have difficulties, and clinician assessment and ongoing review is crucial in determining which children are likely to benefit from a DPI. Consistent correct use and adherence remain as challenges, but these are also issues with an MDI plus spacer and do not appear to be significantly worse with DPIs. Evidence of the use of DPIs during acute illness is limited; more studies are required in this setting.

Peak Nasal Inspiratory Flow (PNIF) for Nasal Breathing Evaluation.

Measuring nasal airflow and nasal breathing has been a major goal of rhinology. Many objective methods for measuring nasal airflow or nasal airway resistance or dimensions provide valuable data but are time-consuming and require expensive equipment and trained technicians, thus making these methods less practical for clinical practice. Peak nasal inspiratory flow (PNIF) measurement is fast, unexpensive, noninvasive, and able to provide an objective evaluation of nasal airflow in real-time. Unilateral PNIF measurements allow separated evaluation of each side of the nasal airway and may prove particularly useful when clinical assessment detects significant asymmetry between both nasal cavities.PNIF measurements are most useful for assessing changes in nasal airflow achieved by any form of therapy, including surgical treatment of the nasal airway. These measurements generally correlate with other objective methods for nasal airway evaluation, but not unequivocally with patient-reported evaluation of nasal breathing. Nevertheless, as low PNIF values prevent the sensation of a suitable nasal breathing, PNIF measurement may also prove useful to optimize the decision of how to best address patients with complaints of nasal airway obstruction.

Peak nasal inspiratory flow in children and adolescents with sickle cell disease: a case-control study.

Sickle cell disease is the most frequent of the hereditary hemoglobinopathies and it presents multisystemic effects. A manifestation that is commonly found in sickle cell disease is upper airway obstruction, particularly adenotonsillar hypertrophy. This study aims to evaluate the peak nasal inspiratory flow measurements of children and adolescents with sickle cell disease. This is a case-control study on children aged between 8 and 15 years who were diagnosed with sickle cell disease. Peak nasal inspiratory flow measurements were obtained from patients. A total of 279 patients were enrolled in this study, with 93 in the case group and 186 in the control group. The case group had an 82.83% chance of having lower peak nasal inspiratory flow values than the control group. In the case group, 75% of the peak nasal inspiratory flow values were in the lower standards, whereas in the control group, only 25% were in the lower standards. This study showed a high prevalence of reduced peak nasal inspiratory flow values in children with sickle cell disease and could certainly be incorporated into the day-to-day clinical evaluation of patients as a screening instrument.

Efficacy and safety of a hypertonic nasal wash solution containing sea algae extracts in patients that underwent surgical correction of a deviated nasal septum and radiofrequency turbinate volume reduction.

The objective of this study was to evaluate efficacy and safety of a Hypertonic Seawater Solution (2.3% NaCl) containing brown and blue-green Algae (HSS-A) in comparison to Isotonic Saline Solution (ISS) regarding the improvement of nasal breathing in patients that have undergone surgical correction of a deviated nasal septum and radiofrequency turbinate volume reduction. A total of 101 individuals were enrolled in the study (HSS-A: 57; ISS: 44). Nasal breathing was evaluated using a Peak Nasal Inspiratory Flow (PNIF) measurement device at four timepoints: prior to surgical intervention (up to 30 days pre-surgery) and at the 2nd, 10th and 20th postoperative days. On the 20th postoperative day, patients also answered a Nasal Surgical Questionnaire (NSQ) evaluating breathing ability and overall satisfaction from the use of both nasal sprays. No significant differences were observed in PNIF measurements between groups at different points. On the 20th postoperative day, NSQ analysis showed that ISS-treated patients had more frequently moderate nasal bleeding compared to the HSS-A group (85.7% vs. 14.3%, p=0.038). No other statistically significant differences were observed between groups. When NSQ parameters were evaluated in a binary mode, a trend for reduced crusting scores was seen in the HSS-A group (15.9% vs. 35.5% in ISS, p=0.053). No safety concerns were reported throughout the study. In patients that have undergone surgical correction of a deviated nasal septum and radiofrequency turbinate volume reduction, PNIF values did not differ significantly in patients receiving HSS-A and ISS solutions. Nasal bleeding was more frequent in ISS patients versus HSS-A. Overall, both solutions provided symptomatic relief and use satisfaction in the absence of side effects.

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.

Critical to Know Pcrit: A Review on Pharyngeal Critical Closing Pressure in Obstructive Sleep Apnea.

It is crucial to understand the underlying pathophysiology of obstructive sleep apnea (OSA). Upper airway collapsibility is an important pathophysiological factor that affects the upper airway in OSA. The aim of the current study was to review the existing body of knowledge on the pharyngeal collapsibility in OSA. After a thorough search through Medline, PubMed, Scopus, and Web of science, the relevant articles were found and used in this study. Critical closing pressure (Pcrit) is the gold standard measure for the degree of collapsibility of the pharyngeal airway. Various physiological factors and treatments affect upper airway collapsibility. Recently, it has been shown that the baseline value of Pcrit is helpful in the upfront selection of therapy options. The standard techniques to measure Pcrit are labor-intensive and time-consuming. Therefore, despite the importance of Pcrit, it is not routinely measured in clinical practice. New emerging surrogates, such as finite element (FE) modeling or the use of peak inspiratory flow measurements during a routine overnight polysomnography, may enable clinicians to have an estimate of the pharyngeal collapsibility. However, validation of these techniques is needed.

The relationship between peak inspiratory flow and hand grip strength measurement in men with mild chronic obstructive pulmonary disease

BackgroundChronic obstructive pulmonary disease (COPD) decreases quality of life and muscular strength. Inspiratory flow is important for inhalants in the bronchi but is complicated to measure in routine practice. We hypothesized that hand grip strength (HGS) would correlate with inhalation rate in patients with mild COPD.MethodsThe COPD patients were recruited at the St. Marianna University School of Medicine, Yokohama Seibu Hospital, from 2015 to 2018. We measured peak inspiratory flow (PIF) through an In-Check flow meter attached with Diskus [PIF(D)] and Turbuhaler [PIF(T)] inhalers. The 6-min walking test (6MWT), and the fraction of exhaled nitric oxide (FENO), spirometry, HGS, or forced oscillation technique (FOT) parameters were measured.ResultsForty-four subjects were enrolled. All were men, with a mean age (± SD) of 77.8 ± 9.36 years. Thirty-nine patients had mild COPD. PIF(D) was 110 (80, 140) L/min (median, interquartile range), PIF(T) was 80 (70, 90) L/min, and HGS was 28.7 (13.8, 43.6) kgf. PIF(D) and PIF(T) were significantly correlated (r = 0.443, p = 0.003). PIF(D) was significantly correlated with age (r = − 0.327, p = 0.030) and HGS (r = 0.326, p = 0.031). PIF(T) was significantly correlated with age (r = − 0.328, p = 0.030), FVC (r = 0.351, p = 0.019), 6MWT distance (r = 0.392, p = 0.011), and HGS (r = 0.328, p = 0.030).ConclusionHGS might be more useful for predicting PIF than other parameters. Also, elderly COPD patients need to be taught inhaled methods carefully.

Relationship between Peak Inspiratory Flow and Patient and Disease Characteristics in Individuals with COPD-A Systematic Scoping Review.

Optimal delivery of medication via dry powder inhalers, the most commonly prescribed inhaler type, is dependent on a patient achieving a minimum level of inspiratory flow during inhalation. However, measurement of peak inspiratory flow (PIF) against the simulated resistance of a dry powder inhaler is not frequently performed in clinical practice due to time or equipment limitations. Therefore, defining which patient characteristics are associated with lower PIF is critically important to help clinicians optimize their inhaler choice through a more personalized approach to prescribing. The objective of this scoping review was to systematically evaluate patient and disease characteristics determining PIF in patients with chronic obstructive pulmonary disease (COPD). Medline, Cochrane and Embase databases were systematically searched for relevant studies on PIF in patients with COPD published in English between January 2000 and May 2021. The quality of evidence was assessed using a modified Grading of Recommendations Assessment, Development and Evaluation checklist. Of 3382 citations retrieved, 35 publications were included in the review (nine scored as high quality, 13 as moderate, nine as low, and four as very low). Factors correlating with PIF in >70% of papers included both patient characteristics (lower PIF correlated with increased age, female gender, shorter height, decreased handgrip and inspiratory muscle strength, and certain comorbidities) and disease characteristics (lower PIF correlated with markers of lung hyperinflation, lower peak expiratory flow [PEF] and increased disease severity). Other factors correlating with adequate/optimal or improved PIF included education/counseling and exercise/inspiratory muscle training; impaired physical function and errors in inhalation technique/non-adherence were associated with low/suboptimal PIF. In conclusion, clinicians should measure PIF against the simulated resistance of a particular device wherever possible. However, as this often cannot be done due to lack of resources or time, the patient and disease characteristics that influence PIF, as identified in this review, can help clinicians to choose the most appropriate inhaler type for their patients.

Assessment of nasal obstruction by subjective methods and peak nasal inspiratory flow in children and adolescents with chronic rhinitis.

Nasal obstruction (NO) is the most irritating symptom of chronic rhinitis (CR). The results of studies that correlated subjective and objective methods of NO in children and adults were contradictory. To analyze the correlation between subjective NO scales and peak nasal inspiratory flow (PNIF) measurements and compare the subjective NO assessment and PNIF in children by age. Participants were patients with CR. The correlation between the subjective NO assessment using a visual analog scale (NO-VAS) and the Nasal Obstruction Symptom Evaluation (NOSE) and nasal airflow measurement pre- and post-vasoconstrictor administration using the PNIF was estimated. The differences in the subjective NO assessment and PNIF between children aged 8-11 years and 12-15 years were analyzed. A total of 79 patients aged 8-15 years were included. No correlation was established between the NO-VAS and the PNIF before and after vasoconstrictor administration (r = -0.19; p = 0.11 and r = -0.18; p = 0.15 respectively) or between the NOSE and the baseline PNIF (r = -0.23; p = 0.07). Differences were observed in the PNIF between children aged 8-11 years and 12-15 years (p =<0.0001), but there were no differences in the subjective perception assessed with the NO-VAS (p = 0.7591). No correlation was demonstrated between the subjective NO score and the PNIF in children and adolescents with CR. Older children have a lower perception of NO than younger ones. Subjective NO scales cannot replace the PNIF measurement in patients with rhinitis.

Assessment of peak inspiratory flow in the management of acute inspiratory dyspnoea

Assessment of inspiratory dyspnoea associated with upper airway obstruction is based on subjective clinical and nasal fibreoptic laryngoscopy (NFL) signs. The aim of this study was to determine whether peak inspiratory flow (PIF) measurement could indicate the need for upper airway release surgery in patients with acute inspiratory dyspnoea during emergency. A retrospective single-institution study (February 2018-March 2020) of 48 patients with acute inspiratory dyspnoea and PIF measurement (Peak Flow In-Check Dial G16®-Harlow-England) was conducted. The surgical decision was based on the clinical evaluation of the patient's respiratory tolerance and NFL. Forty-eight patients were included in this study. Thirty-five patients underwent surgery (PIF: 36 L/min), and 13 patients did not (PIF: 58 L/min) (p = 0.0009). Three of these 13 patients underwent an operation later (PIF value: 42 L/min versus 63 L/min for the 10 others [p = 0.25]). PIF measurement is a quantitative, objective, inexpensive, non-invasive, and quick test that is potentially useful for general practitioners, mobile medical teams, or for ear-nose-and-throat specialists. A threshold of 42 L/min can help doctors in emergency decision making to refer patients to an ear-nose-and-throat specialist to release the upper airway and perform surgery or to choose medical monitoring for patients with emergency inspiratory dyspnoea.

Investigation of Repeatability of Peak Nasal Inspiratory Flow Rate Measurements Under Baseline Conditions and After Administration of 0.05% Oxymetazoline.

Peak nasal inspiratory flow (PNIF) measurement is an inexpensive and user-friendly method to assess nasal patency. However, the repeatability of PNIF measurements, as well as the threshold value of a change in PNIF, which can be considered significant remain unclear. This study aims to investigate the repeatability of PNIF measurements and the change in PNIF after the administration of 0.05% oxymetazoline. Repeated measurements of PNIF (Clement Clarke In-Check nasal inspiratory flow meter; Clement Clarke International, Ltd, Harlow, Essex, UK) were obtained in 333 healthy volunteers (174 women). Based on age, participants were categorized into three groups (6-7 years, 13-14 years, and 20-45 years). We obtained five measurements in each participant. PNIF was remeasured in 294 subjects 30 min after administration of 0.05% oxymetazoline. The variability in PNIF measurements was assessed using the coefficient of variation (CV = standard deviation × 100%/mean). The first four PNIF measurements significantly differed from each other. The difference in PNIF measurements ceased to be statistically significant only between the fourth and fifth measurements (p = 0.19). PNIF repeatability was acceptable; the median CV was 15.5% (0-66), which did not significantly differ between age groups. The administration of 0.05% oxymetazoline led to a statistically significant increase in the PNIF value by 14.3% (-45, 157%) (p = 0.000000). 1. No statistically significant difference was observed in PNIF values only between the fourth and fifth measurements; therefore, at least three measurements are essential to draw meaningful conclusions. 2. PNIF measurements were satisfactorily characterized by a relatively low CV (15%). 3. The administration of 0.05% oxymetazoline led to an increase in PNIF by approximately 14% over the baseline value.

Peak In- and Expiratory Flow Revisited: Reliability and Reference Values in Adults

Background: While peak in- and expiratory flow rates offer valuable information for diagnosis and monitoring in respiratory disease, these indices are usually considered too variable to be routinely used for quantification in clinical practice. Objectives: The aim of the study was to obtain reproducible measurements of maximal inspiratory flow rates and to construct reference equations for peak in- and expiratory flows (PIF and PEF). Method: With coaching for maximal effort, 187 healthy Caucasian subjects (20–80 years) performed at least 3 combined forced inspiratory and expiratory manoeuvres, until at least 2 peak inspiratory flow measurements were within 10% of each other. The effect on PIF preceded by a slow expiration instead of a forced expiration and PIF repeatability over 3 different days was also investigated in subgroups. Reference values and limits of normal for PIF, mid-inspiratory flow, and PEF were obtained according to the Lambda-Mu-Sigma statistical method. Results: A valid PIF could be obtained within 3.3 ± 0.6(SD) attempts, resulting in an overall within-test PIF variability of 4.6 ± 3.2(SD)%. A slow instead of a forced expiration prior to forced inspiration resulted in a significant (p < 0.001) but small PIF increase (2.5% on average). Intraclass correlation coefficient for between-day PIF was 0.981 (95% CI: 0.960–0.992). Over the entire age range, inter-subject PIF variability was smaller than in previous reports, and PIF could be predicted based on its determinants gender, age, and height (r² = 0.53). Conclusions: When adhering to similar criteria for the measurement of effort-dependent portions of inspiratory and expiratory flow-volume curves, performed according to current ATS/ERS standards, it is possible to obtain reproducible PIF and PEF values for use in routine clinical practice.

Reference Value of Nasal Peak Inspiratory Flow Rate in Indian Children: A Cross-sectional Study

Introduction: Peak Nasal Inspiratory Flow (PNIF) measurement is a basic, convenient, easy to use and low cost method of determining the nasal airway patency. However, normative data for paediatric population is scarce and not available for Indian children aged 6 to 12 years. Aim: To establish reference value of PNIF in Indian children aged 6 to 12 years of age. Materials and Methods: A descriptive cross-sectional study was conducted between July 2012 and June 2013 in the Himalayan range of east Sikkim district and Sub-Himalayan Terai region of Darjeeling district of West Bengal. Total 1001 children aged 6 to 12 years were selected from 16 schools by simple random sampling. Of these 1001 children, 784 children were enrolled in the study after taking into account inclusion and exclusion criteria. Repeated PNIF measurements were taken from these 784 children. Mean PNIF value was calculated. The effect of age and height on PNIF was studied. The mean and standard deviation of Peak Inhalation Flow Rate (PIFR) are calculated and compared across groups using a one-way ANOVA test. Regression analysis was done to establish an equation of predicting PNIF level based on height for normal children. The analysis was carried out using Statistical Package for Social Sciences (SPSS) version 16 statistical software. An alpha level of 5% was chosen, which means that any p-value less than 0.05 was considered significant. Results: Mean value of PNIF age group; 6-7 years-53.36 L/min, &gt;7-8 years-56.79 L/min, &gt;8-9 years-63.91 L/min, &gt;9-10 years- 69.45 L/min, &gt;10-11years- 80.71 L/min, &gt;11-12 years-85.69 L/ min. PNIF increases with age and height. A simple formula has also been established to calculate mean PNIF at a given height. PNIF or PIFR (L/min)=-52.716+0.945×height in cm. Conclusion: PNIF measurements are possible in children aged six years and older. Age and height also affect PNIF.

The Correlation Between Objective Peak Nasal Inspiratory Flow Measurements (PNIF) And Subjective Allergy Symptom Assessments In The Environmental Exposure Unit (EEU)

The Correlation Between Objective Peak Nasal Inspiratory Flow Measurements (PNIF) And Subjective Allergy Symptom Assessments In The Environmental Exposure Unit (EEU)

Efficacy of a Quail Eggs-Based Dietary Supplement for Allergic Rhinitis: Results of a Single-Arm Trial

Previous data suggested the potential treatment effect of a proprietary quail eggs-based blend on allergic rhinitis (AR) symptoms, induced by allergen challenge. We herein aimed to investigate the efficacy and safety of a similar dietary supplement, comprising the bioactive ingredients of quail eggs and the zinc mineral, in the setting of active AR. Adult patients (n = 77), aged 18- 60 years, with mild, intermittent AR were enrolled in this single-arm, open-label trial. Patients’ responses were assessed based on peak nasal inspiratory flow (PNIF) measurements at two visits (Day 1/Visit 1 and Day 7/Visit 2) and self-rating of AR-associated symptoms on a Visual Analog Scale (VAS) throughout the entire 7-day study period. PNIF values at 15, 30, 60, 90 and 120 min (Visit 1) following administration of an oral dose of the study product were the primary efficacy endpoint. PNIF values (Visit 1) gradually increased from baseline (pre-treatment), with statistical significance first reached 30 min later (p = 0.002). VAS scores (Visit 1) for all AR symptoms gradually decreased with statistical significance first reached at 15 min (rhinorrhea, p = 0.042; itchy nose, p = 0.001; sneezing p < 0.001), 30 min (nasal congestion, p < 0.001; itchy eyes, p = 0.003) or 60 min (watery eyes, p = 0.04). PNIF improvement and decline of VAS scores were significantly more apparent at Visit one vs. Visit 2. Treatment-emergent adverse events were limited to cough and muscle strain (one patient each). Our results support the efficacy, rapid mode of action and tolerability of the investigated product for symptomatic treatment of mild intermittent AR.

A New Technique for Robust Stabilization in the Keystone Area during Extracorporeal Septorhinoplasty.

Although extracorporeal septorhinoplasty is the most powerful technique for correcting deviated and leaning noses, many investigators have abandoned it because of keystone problems. The authors defined a new neoseptum fixation technique and used it in 10 patients in 2016. Preoperative and postoperative Nasal Obstruction Symptom Evaluation scale and peak nasal inspiratory flow measurement, and septal indexes of the patients were compared. There was statistically significant improvement in the respiratory condition of all patients. No recurrence or dorsal irregularity has been observed. This new, easily applicable, and robust fixation method of extracorporeal septorhinoplasty may be a definitive solution to prevent keystone irregularities. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, IV.

Peak nasal inspiratory flow measurement and visual analogue scale in a large adult population.

Nasal obstruction is the most common symptom in nasal diseases. It can be evaluated objectively, that is by means of peak nasal inspiratory flow (PNIF) measures and/or subjectively by means of validated questionnaires. However, it has been reported that there is a lack of reliable correlation between subjective and objective measurements of nasal obstruction. The aim of the present study was to evaluate the correlation between PNIF measurements and the subjective sensation of nasal obstruction measured by means of a visual analogue scale (VAS) in a large population of consecutive rhinologic patients. Prospective clinical study. Tertiary rhinological referral centre. A total of 641 consecutive subjects were enrolled. Visual analogue scale and PNIF were performed to assess nasal obstruction. Nasal septal deviation was classified according to Mladina classification, and its severity was assessed using three levels of severity. Although weak, there was a significant negative correlation (r=-0.13, P=0.001) between PNIF and VAS. Dividing the population in those affected by nasal septal deviation (NSD) and those affected by chronic rhinosinusitis (CRS), a week negative correlation between PNIF and VAS was again confirmed in both groups (r=-0.208, P=0.006 for NSD and r=-0.13, P=0.04 for CRS). Peak nasal inspiratory flow and VAS were also evaluated according to the grade of polyps and the type and level of septal deviation. Visual analogue scale and PNIF significantly correlated, although with a low degree, in a large population of rhinologic patients. Peak nasal inspiratory flow, being cheap and simple to use, could be a good candidate to assist clinicians dealing with "airway" diseases in their daily clinical practice in order to provide comprehensive information on nasal function. Peak nasal inspiratory flow can in fact give some important rough insights on VAS, but these measurements cannot be alternative to each other.

Spirometry Measurement of Peak Inspiratory Flow Identifies Suboptimal Use of Dry Powder Inhalers in Ambulatory Patients with COPD.

Determine the prevalence of suboptimal peak inspiratory flow rate (PIFR) and associated patient characteristics and compare PIFR measurements obtained with spirometry and In-Check DIAL® device in ambulatory patients with COPD. Patients underwent PIFR measurement with In-Check DIAL® device and pulmonary function testing with calibrated equipment. Group characteristics and lung function were compared for patients with suboptimal (≤ 60 L/min) and optimal (> 60 L/min) PIFR. Receiver operating curve analysis determined the best maximal forced inspiratory flow (FIF max) value in identifying optimal PIFR by gender and height. From July 1, 2016 to January 31, 2018, a total of 303 patients with chronic obstructive pulmonary disease (COPD) had PIFR and pulmonary function measurements. Group mean age was 65.5 ± 11.3 years with equal gender distribution. Suboptimal PIFR was observed in 61 (20.1%) patients. A significant correlation was observed between PIFR and FIF max, inspiratory capacity and residual volume (RV) to total lung capacity (TLC) ratio. In the suboptimal PIFR group, mean FIF max measured by spirometry was significantly less compared with the optimal PIFR group; 178.5 ± 56.9 L/min and 263.4 ± 89.9 L/min, respectively (p<0.0001). Receiver operator curve analysis of FIF max to identify an optimal PIFR yielded an area under the curve of 0.79. Males < 65 inches had a suboptimal PIFR in 16.7 % of the male cohort, while females < 65 inches had a suboptimal PIFR in 27.4 % of the women. Suboptimal PIFR was present in 1 in 5 stable patients with COPD and was more frequent in short statured females. Spirometry determined FIF max was associated with PIFR based on gender and height.

Unilateral and Bilateral PNIF in Quality Control of Nasal Septal Surgery.

The aim of this study was to explore the usefulness of unilateral, combined unilateral (left + right), and bilateral peak nasal inspiratory flow (PNIF) measurements in assessing the results of nasal septal surgery. Nasal obstruction was recorded subjectively and objectively before and 4 months after nasal septoplasty using a visual analogue scale (VAS) and a PNIF meter. Nasal septoplasty (58 patients) and septoplasty with turbinoplasty (68 patients) were performed on 126 patients (85 males; 41 females) with a mean age of 32.8 years. The results showed a significant improvement in VAS scores, as well as unilateral, combined unilateral, and bilateral PNIF values after both septoplasty and septoplasty with turbinoplasty. Septoplasty with turbinoplasty showed better improvement in VAS and PNIF scores than septoplasty alone and this was significant for bilateral PNIF scores. The best unilateral pre- and postoperative correlations between VAS and PNIF measurements were found using the lower of the two unilateral PNIF scores, irrespective of side. In the total material, VAS/PNIF correlations were mostly significant, but weak (all r<0.30). We found VAS and PNIF to be useful instruments in reporting results of surgery. The weak correlations between VAS and PNIF measurements suggest that these subjective and objective instruments may target different aspects of nasal obstruction.

Patient experience of nasal obstruction and its clinical assessment.

The correlation between objective and subjective nasal obstruction is poor, and dissatisfaction rates after surgery for nasal obstruction are high. Accordingly, novel assessment techniques may be required. This survey aimed to determine patient experience and preferences for the measurement of nasal obstruction. Prospective survey of rhinology patients. Of 72 questionnaires distributed, 60 were completed (response rate of 83 per cent). Obstruction duration (more than one year) (χ2 = 13.5, p = 0.00024), but not obstruction severity, affected willingness to spend more time being assessed. Questionnaires (48 per cent) and nasal inspiratory peak flow measurement (53 per cent) are the most commonly used assessment techniques. Forty-nine per cent of participants found their assessment unhelpful in understanding their obstruction. Eighty-two per cent agreed or strongly agreed that a visual and numerical aid would help them understand their blockage. Many patients are dissatisfied with current assessment techniques; a novel device with visual or numerical results may help. Obstruction duration determines willingness to undergo longer assessment.