Abstract
Introduction Pathophysiology changes associated with pleural effusion, its drainage and factors governing symptom response are poorly understood. Our objective was to determine: 1) the effect of pleural effusion (and its drainage) on cardiorespiratory, functional and diaphragmatic parameters; and 2) the proportion as well as characteristics of patients with breathlessness relief post-drainage.
Methods Prospectively enrolled patients with symptomatic pleural effusions were assessed at both pre-therapeutic drainage and at 24–36 h post-therapeutic drainage.
Results 145 participants completed pre-drainage and post-drainage tests; 93% had effusions ≥25% of hemithorax. The median volume drained was 1.68 L. Breathlessness scores improved post-drainage (mean visual analogue scale (VAS) score by 28.0±24 mm; dyspnoea-12 (D12) score by 10.5±8.8; resting Borg score before 6-min walk test (6-MWT) by 0.6±1.7; all p<0.0001). The 6-min walk distance (6-MWD) increased by 29.7±73.5 m, p<0.0001. Improvements in vital signs and spirometry were modest (forced expiratory volume in 1 s (FEV1) by 0.22 L, 95% CI 0.18–0.27; forced vital capacity (FVC) by 0.30 L, 95% CI 0.24–0.37). The ipsilateral hemi-diaphragm was flattened/everted in 50% of participants pre-drainage and 48% of participants exhibited paradoxical or no diaphragmatic movement. Post-drainage, hemi-diaphragm shape and movement were normal in 94% and 73% of participants, respectively. Drainage provided meaningful breathlessness relief (VAS score improved ≥14 mm) in 73% of participants irrespective of whether the lung expanded (mean difference 0.14, 95% CI 10.02–0.29; p=0.13). Multivariate analyses found that breathlessness relief was associated with significant breathlessness pre-drainage (odds ratio (OR) 5.83 per standard deviation (sd) decrease), baseline abnormal/paralyzed/paradoxical diaphragm movement (OR 4.37), benign aetiology (OR 3.39), higher pleural pH (OR per sd increase 1.92) and higher serum albumin level (OR per sd increase 1.73).
Conclusions Breathlessness and exercise tolerance improved in most patients with only a small mean improvement in spirometry and no change in oxygenation. Breathlessness improvement was similar in participants with and without trapped lung. Abnormal hemi-diaphragm shape and movement were independently associated with relief of breathlessness post-drainage.
Abstract
The majority of patients improve after pleural fluid drainage. Abnormal diaphragmatic function may be an important contributor to breathlessness in patients with pleural effusion. http://bit.ly/2SyF8RW
Footnotes
This article has an editorial commentary: https://doi.org/10.1183/13993003.00501-2020
This article has supplementary material available from erj.ersjournals.com
This study is registered at https://www.anzctr.org.au/ with identifier number ACTRN12616000820404.
Author contributions: S. Muruganandan and M. Azzopardi are joint first authors. Y.C.G. Lee and R. Thomas conceived the initial trial concept with advice from B. Singh and P.R. Eastwood (diaphragm and respiratory physiology) and S. Jenkins (breathlessness scores and 6MWT). Together, these authors developed and modified the trial design and protocol. C.A. Read is the trial manager and oversees data collection and administrative matters. S. Muruganandan, R. Thomas, D.B Fitzgerald and M. Azzopardi were the trial coordinators, recruited patients and collected data. Y.J. Kuok and R. Thomas assessed the radiographs independently. H.M. Cheah assisted with database and data management. K. Murray and C.A. Budgeon were responsible for the statistical analyses. Y.C.G. Lee is the chief investigator and takes overall responsibility for all aspects of trial design, the protocol and trial conduct. All authors have read and approved the final manuscript.
Support statement: This project has received project grant funding from the Cancer Council of Western Australia and the Sir Charles Gairdner Research Advisory Group. Funding information for this article has been deposited with the Crossref Funder Registry.
Conflict of interest: S. Muruganandan has nothing to disclose.
Conflict of interest: M. Azzopardi has nothing to disclose.
Conflict of interest: R. Thomas has nothing to disclose.
Conflict of interest: D.B Fitzgerald has nothing to disclose.
Conflict of interest: Y.J. Kuok has nothing to disclose.
Conflict of interest: H.M. Cheah has nothing to disclose.
Conflict of interest: C.A. Read has nothing to disclose.
Conflict of interest: C.A. Budgeon has nothing to disclose.
Conflict of interest: P.R. Eastwood has nothing to disclose.
Conflict of interest: S. Jenkins has nothing to disclose.
Conflict of interest: B. Singh has nothing to disclose.
Conflict of interest: K. Murray has nothing to disclose.
Conflict of interest: Y.C.G. Lee has served on the advisory board of CareFusion/BD Ltd and has previously led clinical trials for which Rocket Medical plc (UK) provided the drainage kits for study participants without charge, as well as providing an unrestricted educational grant to assist the running of the trial.
- Received May 15, 2019.
- Accepted February 5, 2020.
- Copyright ©ERS 2020