Multiple breath washout: A noninvasive tool for identifying lung disease in symptomatic military deployers

Zell-Baran, L.; Krefft, S.D.; Moore, Camille M.; Wolff, Jenna; Meehan, Richard T.; Rose, Cecile S.

doi:10.1016/j.rmed.2020.106281

Cited by 10 publications

(8 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our findings may be helpful in predicting prognosis and guiding clinical management of military personnel with respiratory symptoms following deployment. Additionally, quantitative HRCT findings may inform or enhance the diagnostic value of newer non-invasive markers of deployment-related lung disease such as the lung clearance index score from multiple breath washout testing [ 49 ] or measures of resistance and reactance using impulse oscillometry [ 43 ].…”

Section: Discussionmentioning

confidence: 99%

Quantitative imaging analysis detects subtle airway abnormalities in symptomatic military deployers

et al. 2022

View full text Add to dashboard Cite

Background Exposure to inhalational hazards during post-9/11 deployment to Southwest Asia and Afghanistan puts military personnel at risk for respiratory symptoms and disease. Pulmonary function and qualitative chest high resolution computed tomography (HRCT) are often normal in “deployers” with persistent respiratory symptoms. We explored the utility of quantitative HRCT imaging markers of large and small airways abnormalities, including airway wall thickness, emphysema, and air trapping, in symptomatic deployers with clinically-confirmed lung disease compared to controls. Methods Chest HRCT images from 45 healthy controls and 82 symptomatic deployers with asthma, distal lung disease or both were analyzed using Thirona Lung quantification software to calculate airway wall thickness (by Pi10), emphysema (by percentage of lung volume with attenuation < -950 Hounsfield units [LAA%-950]), and three parameters of air trapping (expiratory/inspiratory total lung volume and mean lung density ratios, and LAA%-856). SAS v.9.4 was used to compare demographic and clinical characteristics between deployers and controls using Chi-Square, Fisher Exact or t-tests. Linear regression was used to assess relationships between pulmonary function and quantitative imaging findings. Results Gender and smoking status were not statistically significantly different between groups, but deployers were significantly younger than controls (42 vs 58 years, p < 0.0001), had higher body mass index (31 vs 28 kg/m2, p = 0.01), and had fewer total smoking pack-years (8 vs. 26, p = 0.007). Spirometric measures were not statistically significantly different between groups. Pi10 and LAA%-950 were significantly elevated in deployers compared to controls in unadjusted analyses, with the emphysema measure remaining significantly higher in deployers after adjustment for age, sex, smoking, BMI, and expiratory total lung volume. Air trapping parameters were more common in control images, likely due to differences in age and smoking between groups. Among deployers, LAA%-950 and Pi10 were significantly correlated with spirometric markers of obstruction based on ratio of forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) and/or percent predicted FEV1. Conclusions Quantitative chest HRCT imaging analysis identifies emphysema in deployers with asthma and distal lung disease, and may be useful in detecting and monitoring deployment-related lung disease in a population where spirometry is typically normal.

show abstract

Section: Discussionmentioning

confidence: 99%

Quantitative imaging analysis detects subtle airway abnormalities in symptomatic military deployers

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Elevated mdedge.com/fedprac lung clearance index values suggest ventilation heterogeneity and have been shown to be higher among deployed veterans with dyspnea. 26,27 Finally, advanced CT analytic techniques may help identify functional small airways disease and are higher in deployed service members with constrictive bronchiolitis on surgical lung biopsy. 28 These innovative noninvasive techniques are experimental but promising, especially as part of a broader evaluation of small airways disease.…”

Section: Discussionmentioning

confidence: 99%

Postdeployment Respiratory Health: The Roles of the Airborne Hazards and Open Burn Pit Registry and the Post-Deployment Cardiopulmonary Evaluation Network

Davis¹

2022

Federal Practitioner

View full text Add to dashboard Cite

“…However, given that pulmonary function was similar across groups, the present study’s findings may be considered consistent with that of Hirshberg and colleagues [ 24 ]. Zell-Baran et al [ 7 ] observed greater lung clearance index, suggestive of small airway injury, among previously deployed individuals (n = 71) with higher blast exposure intensity scores. This association was no longer significant after adjustment and no other pulmonary function parameters were considered.…”

Section: Discussionmentioning

confidence: 99%

“…This study was limited by reliance on a dichotomous, self-reported representation of blast exposure, and did not assess physiological outcomes. An alternative methodology to classify blast exposure was recently described by Zell-Baran et al [ 7 ] who developed a ‘blast exposure intensity score’ that was the sum of the product of deployment length (months) and frequency (days·month −1 ) of IED blasts and controlled detonations. Investigators observed an unadjusted association between their blast exposure severity score and lung clearance index (marker of ventilation heterogeneity) in 71 deployed individuals that was interpreted as evidence for a link between blast exposure and small airways injury.…”

Section: Introductionmentioning

confidence: 99%

Relationship between clinician documented blast exposure and pulmonary function: a retrospective chart review from a national specialty clinic

Therkorn

Sotolongo

et al. 2022

Respir Res

View full text Add to dashboard Cite

Background Service member exposure to explosive blast overpressure waves is common with considerable attention to traumatic brain injury (TBI) and neuropsychological sequalae. Less is known about the impacts on the respiratory system, particularly long-term effects, despite vulnerability to overpressure. Using a national registry, we previously observed an independent relationship between self-reported blast exposure and respiratory symptoms; however, the impact on objective measures of pulmonary function is poorly understood. Methods 307 Veterans referred to our national specialty center for post-deployment health concerns underwent a comprehensive multi-day evaluation that included complete pulmonary function testing (PFT), occupational and environmental medicine history, neuropsychological or psychological evaluation. We developed an a priori chart abstraction process and template to classify Veterans into blast exposure groups: (1) none, (2) single-mild, or (3) multiple-mild. This template focused primarily on clinician documented notes of blast related TBI that were used as proxy for blast overpressure injury to thorax. PFT variables characterizing flow (FEV1%; %∆FEV1), volume (TLC%), diffusion (DLCO%) and respiratory mechanics (forced oscillometry) were selected for analysis. Results Veterans (40.5 ± 9.7 years; 16.3% female) were referred 8.6 ± 3.6 years after their last deployment and presented with considerable comorbid conditions and health problems (e.g., 62% post-traumatic stress, 55% dyspnea). After chart abstraction, Veterans were assigned to none (n = 208), single mild (n = 52) and multiple mild (n = 47) blast exposure groups. Among the blast exposed, clinicians documented 73.7% were < 50 m from the blast and 40.4% were physically moved by blast. PFT outcome measures were similar across all groups (p value range: 0.10–0.99). Conclusions In this referred sample of deployed Veterans, PFT measures of flow, volume, diffusion, and respiratory mechanics were not associated with clinician documented blast exposure per the retrospective chart abstraction methodology applied. Yet, these clinical findings suggest future research should determine and assess distinction between Veteran recollections of perceived blast experiences versus overpressure wave exposure to the respiratory system.

show abstract

Multiple breath washout: A noninvasive tool for identifying lung disease in symptomatic military deployers

Cited by 10 publications

References 49 publications

Quantitative imaging analysis detects subtle airway abnormalities in symptomatic military deployers

Quantitative imaging analysis detects subtle airway abnormalities in symptomatic military deployers

Postdeployment Respiratory Health: The Roles of the Airborne Hazards and Open Burn Pit Registry and the Post-Deployment Cardiopulmonary Evaluation Network

Relationship between clinician documented blast exposure and pulmonary function: a retrospective chart review from a national specialty clinic

Contact Info

Product

Resources

About