The lower limit for FEV1/FVC in dive medical assessments: a retrospective study

Introduction: Interpreting pulmonary function test (PFT) results requires a valid reference set and a cut-off differentiating pathological from physiological pulmonary function; the lower limit of normal (LLN). However, in diving medicine it is unclear whether an LLN of 2.5% (LLN-2.5) or 5% (LLN-5) in healthy subjects constitutes an appropriate cut-off. Methods: All PFTs performed at the Royal Netherlands Navy Diving Medical Centre between 1 January 2015 and 1 January 2021 resulting in a forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and/or FEV1/FVC with a Z-score between -1.64 (LLN-5) and -1.96 (LLN-2.5) were included. Records were screened for additional tests, referral to a pulmonary specialist, results of radiological imaging, and fitness to dive. Results: Analysis of 2,108 assessments in 814 subjects showed that 83 subjects, 74 men and nine women, mean age 32.4 (SD 8.2) years and height 182 (7.0) cm, had an FVC, FEV1 and/or FEV1/FVC with Z-scores between -1.64 and -1.96. Of these 83 subjects, 35 (42%) underwent additional tests, 77 (93%) were referred to a pulmonary specialist and 31 (37%) underwent high-resolution CT-imaging. Ten subjects (12%) were declared ‘unfit to dive’ for various reasons. Information from their medical history could have identified these individuals. Conclusions: Use of LLN-2.5 rather than LLN-5 for FEV1/FVC in asymptomatic individuals reduces additional investigations and referrals to a pulmonary specialist without missing important diagnoses, provided a thorough medical history is taken. Adoption of LLN-2.5 could save resources spent on diving medical assessments and protect subjects from harmful side effects associated with additional investigations, while maintaining an equal level of safety.

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“Pulmonary dysfunction in children with Duchenne muscular dystrophy may appear earlier than we thought – analysis using novel methodology based on z-scores."

Archives of Medical Science ◽

10.5114/aoms/119782 ◽

2021 ◽

Author(s):

Eliza Wasilewska ◽

Sylwia Małgorzewicz ◽

Jarosław Meyer-Szary ◽

Karolina Sledzinska ◽

Marek Niedoszytko ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Pulmonary Function ◽

Steroid Therapy ◽

Pulmonary Function Test ◽

Forced Expiratory Volume ◽

Z Score ◽

Factors Affecting ◽

Function Test ◽

Z Scores

IntroductionRespiratory status is one of the main factors affecting the length of survival in patients with Duchenne muscular dystrophy (DMD) – the most common, severe, progressive muscular dystrophy.The aim: (1) to assess pulmonary function in DMD patients using the z-score method and (2) to identify factors affecting it, irrespective of the disease progress.Material and methodsWe evaluated 55 boys (aged 5 – 18 years) with DMD. The spirometry was performed with: forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF) analysis as absolute values (in litres or litres/min), % predicted value (%pv) and z-scores [z]. The need of ventilation support, ambulatory status, steroid therapy were collected.Results25(45%) subjects were non-ambulatory, 38(69%) used steroid therapy. Mean FVC[z] -2.4±2.2, FEV1[z] -2.0±1.9, PEF[z] -1.5±1.3 value significantly decrease with age (r=-0.62/-0.65/-0.55; p<0.001 respectively), after reaching the peak values between 9-12 or 6-9 years of age depending on analysis method (absolute, %pv or z-score). The results fell below normal range (z-score<-1.64) at the age of 9.8/10.4/11.6 years and below 80%pv at 10.7/13.2/13.2 for FVC/FEV1/PEF, respectively. The pulmonary function test results were significantly lower in non-ambulant (p<0.001) and non-steroid patients (p<0.02).ConclusionsAnalysis of pulmonary function test based on z-score shows that deterioration of pulmonary function in DMD males may appear earlier than we thought measured by %pv and absolute values. Early loss of ambulation, lack of or delayed steroid therapy are risk factors for worse pulmonary outcomes. To confirm these findings cohort longitudinal studies are necessary.

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Global Lung Function Initiative 2012 reference equations for spirometry in the Norwegian population

European Respiratory Journal ◽

10.1183/13993003.00443-2016 ◽

2016 ◽

Vol 48 (6) ◽

pp. 1602-1611 ◽

Cited By ~ 33

Author(s):

Arnulf Langhammer ◽

Ane Johannessen ◽

Turid L. Holmen ◽

Hasse Melbye ◽

Sanja Stanojevic ◽

...

Keyword(s):

Lung Function ◽

Reference Values ◽

Vital Capacity ◽

Population Based ◽

Forced Expiratory Volume ◽

Female Adolescents ◽

Norwegian Population ◽

Reference Equations ◽

Z Scores ◽

Lower Limit Of Normal

We studied the fit of the Global Lung Function Initiative (GLI) all-age reference values to Norwegians, compared them with currently used references (European Community for Steel and Coal (ECSC) and Zapletal) and estimated the prevalence of obstructive lung disease.Spirometry data collected in 30 239 subjects (51.7% females) aged 12–90 years in three population-based studies were converted to z-scores.We studied healthy non-smokers comprising 2438 adults (57.4% females) aged 20–90 years and 8725 (47.7% female) adolescents aged 12–19 years. The GLI-2012 prediction equations fitted the Norwegian data satisfactorily. Median±sd z-scores were respectively 0.02±1.03, 0.01±1.04 and −0.04±0.91 for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC in males, and −0.01±1.02, 0.07±0.97 and −0.21±0.82 in females. The ECSC and Zapletal references significantly underestimated FEV1 and FVC. Stricter criteria of obstruction (FEV1/FVC <GLI-2012 lower limit of normal (LLN)) carried a substantially higher risk of obstructive characteristics than FEV1/FVC <0.7 and >GLI-2012 LLN. Corresponding comparison regarding myocardial infarction showed a four-fold higher risk for women.The GLI-2012 reference values fit the Norwegian data satisfactorily and are recommended for use in Norway. Correspondingly, the FEV1/FVC GLI-2012 LLN identifies higher risk of obstructive characteristics than FEV1/FVC <0.7.

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Pattern of Pulmonary Function Test in Patients with Severe Mitral Stenosis

Bangladesh Critical Care Journal ◽

10.3329/bccj.v2i2.24078 ◽

2015 ◽

Vol 2 (2) ◽

pp. 57-59

Author(s):

Umme Salma Khan ◽

Abdullah Al Shafi Majumder ◽

AKM Monwarul Islam ◽

Fazle Rabbi Mohammed

Keyword(s):

Pulmonary Function ◽

Pulmonary Function Test ◽

Mitral Stenosis ◽

Vital Capacity ◽

Forced Expiratory Volume ◽

Female Ratio ◽

Function Test ◽

Male Female Ratio ◽

Restricted Type ◽

Impaired Pulmonary Function

Background: The deterioration in lung function in mitral stenosis correlates with the severity of stenotic valves. A correlation is noted between vital capacity and the severity of dyspnoea in patients with mitral stenosis. This study tried to evaluate the pattern of pulmonary function test in patient with severe mitral stenosis.Materials & Methods: This study involving 56 patients of severe mitral stenosis was performed in a referral cardiovascular center at Dhaka, Bangladesh from January to September, 2011. Colour doppler echocardiography and pulmonary function test were performed in each cases. Forced vital capacity (FVC), forced expiratory volume in first second (FEV1), FEV1/FVC and peak expiratory flow (PEF) rate was assessed from pulmonary function test. Finally, pattern of pulmonary function test in severe mitral stenosis was assessed.Results: Amomg 56 patients, 46 were female with a male female ratio 1: 0.22 and the mean age of patients was 28.76 ± 7.2. Among patients with severe mitral stenosis, mean FEV1 (%) was 60.18 ± 13.054. Minimum FVC (%) was 26, maximum was 90 with mean 53.80 ± 12.313. The PEF varied from 150 to 330 L/minute with mean 223.75 ± 62.3251. In current study, out of 56 patients, 2 cases had obstructive type and rest of the patients had restricted type of airway on pulmonary function.Conclusion: The brief results of this study reveal that severe mitral stenosis is associated with impaired pulmonary function, usually presenting restrictive airway pattern.Bangladesh Crit Care J September 2014; 2 (2): 57-59

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Pulmonary function impairment in patients with chronic heart failure: Lower limit of normal versus conventional cutoff values

Heart & Lung ◽

10.1016/j.hrtlng.2014.03.011 ◽

2014 ◽

Vol 43 (4) ◽

pp. 311-316 ◽

Cited By ~ 3

Author(s):

Armine G. Minasian ◽

Frank J.J. van den Elshout ◽

P.N. Richard Dekhuijzen ◽

Petra J.E. Vos ◽

Frank F. Willems ◽

...

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Pulmonary Function ◽

Lower Limit ◽

Cutoff Values ◽

Function Impairment ◽

Lower Limit Of Normal

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A Method to Derive Lower Limit of Normal for the FEV 1 /Forced Expiratory Volume at 6 s of Exhalation Ratio From FEV 1 /FVC Data

CHEST Journal ◽

10.1378/chest.08-1769 ◽

2009 ◽

Vol 135 (2) ◽

pp. 408-418 ◽

Cited By ~ 7

Author(s):

André Capderou ◽

Malika Berkani ◽

Marie-Hélèene Becquemin ◽

Marc Zelter

Keyword(s):

Lower Limit ◽

Forced Expiratory Volume ◽

Lower Limit Of Normal

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The effectiveness of lower limit of normal criteria and cutoff rate of forced expiratory volume in 1 s/forced expiratory volume in 6 s using in the diagnosis of airway obstruction in chronic obstructive pulmonary disease patients diagnosed with fixed ratio

Eurasian Journal of Pulmonology ◽

10.4103/ejop.ejop_78_18 ◽

2019 ◽

Vol 21 (3) ◽

pp. 175

Author(s):

Gokhan Erdogan ◽

Esra Sonmez ◽

Hisam Alahdab

Keyword(s):

Chronic Obstructive Pulmonary Disease ◽

Airway Obstruction ◽

Pulmonary Disease ◽

Lower Limit ◽

Fixed Ratio ◽

Forced Expiratory Volume ◽

Chronic Obstructive ◽

Obstructive Pulmonary Disease ◽

Cutoff Rate ◽

Lower Limit Of Normal

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Importance of Pre Operative Pulmonary Function Test to Predict Risk of Pulmonary Complications after Abdominal Surgery- An Evidence Based Study

International Journal of Science and Healthcare Research ◽

10.52403/ijshr.20210741 ◽

2021 ◽

Vol 6 (3) ◽

pp. 236-243

Author(s):

Krupa Pareshbhai Patel ◽

Anjali Bhise

Keyword(s):

Abdominal Surgery ◽

Pulmonary Function ◽

Pulmonary Function Test ◽

Meta Analysis ◽

Pulmonary Function Tests ◽

Forced Expiratory Volume ◽

Pulmonary Complications ◽

Evidence Based ◽

Function Tests ◽

Function Test

Background: Spirometry is a universal, simple, and non-invasive pulmonary function test. Spirometry, along with calculation of the forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), is helpful for diagnosing obstructive or restrictive lung disease. Postoperative Pulmonary Complications are defined as unintended pulmonary abnormalities that occur as a result of surgery which cause identifiable dysfunction. Purpose: To find the evidence showing the importance of pre-operative PFT to predict risk of pulmonary complications after abdominal surgery Methodology: The study was conducted according to Preferred Reporting Items for systematic reviews and meta-analysis guidelines. Evidences selected since year 2002- 2020 from PubMed, Google Scholar, Physiotherapy Evidence Database (PEDro), ResearchGate and ScienceDirect. Key words used were: Pulmonary Function Tests, Post-Operative Pulmonary Complications, and Abdominal Surgery. Analysis was done using 2 scales: Centre for Evidence-Based Medicine Levels of Evidence Scale. Total 12 articles were found. Among them 10 were selected. Results: 5 articles showed that preoperative PFT is important in prediction of PPCs while the other half concluded that routine preoperative spirometry is not necessary before non-thoracic surgeries. Conclusion: Based on evidences, in the nutshell it is reviewed that there is controversy regarding the value of preoperative pulmonary functions test in non-thoracic surgeries. Keywords: Pulmonary Function Tests, Post-Operative Pulmonary Complications, and Abdominal Surgery

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Preoperative Pulmonary Function Testing to Predict Recurrence of Chronic Rhinosinusitis With Nasal Polyps

Allergy & Rhinology ◽

10.1177/2152656720946994 ◽

2020 ◽

Vol 11 ◽

pp. 215265672094699

Author(s):

Yuji Nakamaru ◽

Masanobu Suzuki ◽

Aya Honma ◽

Akira Nakazono ◽

Shogo Kimura ◽

...

Keyword(s):

Pulmonary Function ◽

Chronic Rhinosinusitis ◽

Nasal Polyps ◽

Pulmonary Function Tests ◽

Forced Expiratory Volume ◽

Multivariable Logistic Regression Model ◽

Recurrent Group ◽

Function Test ◽

Close Relationship ◽

Function Testing

Background Although the close relationship between the upper and lower airways has been highlighted previously, little is known about the association between lung function and the recurrence of chronic rhinosinusitis with nasal polyps (CRSwNP). This study aimed to evaluate the factors associated with pulmonary function that affect CRSwNP recurrence after surgery. Methods We performed a series of routine pulmonary function tests for general anesthesia prior to CRSwNP surgery. The values for each parameter were compared in the presence or absence of recurrence. Results Sixty-nine patients with CRSwNP were included. The percent predicted forced expiratory volume in one second (%FEV1) in the recurrent group was significantly lower than that in the non-recurrent group ( P = .005). A multivariable logistic regression model revealed that %FEV1 was a positive predictor of recurrence (odds ratio: 0.96, 95% CI: 0.92-0.99, P = .023). There were no significant differences in the other pulmonary functions between the two groups. Conclusions We found that %FEV1 may be a predictor of CRSwNP recurrence after surgery. As %FEV1 is a pulmonary function test that is routinely performed before surgery, this parameter is readily applicable. Moreover, as %FEV1 appears to have the potential to reveal concealed asthma, %FEV1 might be a particularly useful tool for the prediction of CRSwNP recurrence after surgery.

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Unique Pattern of Pulmonary Function after Exercise in Patients with Cystic Fibrosis

Pediatric Exercise Science ◽

10.1123/pes.6.3.275 ◽

1994 ◽

Vol 6 (3) ◽

pp. 275-286 ◽

Cited By ~ 1

Author(s):

Ted. A. Kaplan ◽

Gina Moccia ◽

Robert M. McKey

Keyword(s):

Cystic Fibrosis ◽

Pulmonary Function ◽

Time Course ◽

Forced Expiratory Volume ◽

Distinct Pattern ◽

Degree Pattern ◽

Function Test ◽

The Mean ◽

Exercise Induced ◽

Mean Time

The purpose of this study was to assess the incidence, degree, pattern, and time course of pulmonary function test (PFT) changes measured after a dynamic exercise challenge. Forced expiratory maneuvers were performed before and serially after a 7-min run-walk in 44 patients with cystic fibrosis (CF). Twenty-four patients met at least one PFT criterion for exercise-induced bronchospasm (EIB) within 21 min after exercise, and 38 patients had >5% increase in a PFT parameter at some point after exercise. The mean time of greatest increase in PFTs occurred sooner than the greatest decrease, which was later than for 22 patients with asthma or allergic rhinitis found to have EIB. Age was inversely related to percentage fall in forced expiratory volume in 1 s (FEV,) after exercise. These results demonstrate a distinct pattern of PFTs measured after exercise in most patients with CF, with an early bronchodilation followed by a significant decrease in PFTs.

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