Expiratory flow limitation in patients with pleural effusion

Breathlessness with Pleural Effusion: What Do We Know?

Breathlessness is the most common symptom in individuals with pleural effusion and is often disabling. The pathophysiology of breathlessness associated with pleural effusion is complex. The severity of breathlessness correlates weakly with the size of the effusion. Improvements in ventilatory capacity following pleural drainage are small and correlate poorly with the volume of fluid drained and improvements in breathlessness. Impaired hemidiaphragm function and a compensatory increase in respiratory drive to maintain ventilation appear to be an important mechanism of breathlessness associated with pleural effusion. Thoracocentesis reduces diaphragm distortion and improves its movement; these changes appear to reduce respiratory drive and associated breathlessness by improving the neuromechanical efficiency of the diaphragm.

Bronchodilator Reversibility Occurring during the Acute Phase of Paragonimiasis westermani Infection

A 43-year-old woman was referred to our hospital with peripheral blood hypereosinophilia and abnormal chest X-ray findings. Her pleural effusion revealed hypereosinophilia and a low glucose level. She was diagnosed with pulmonary paragonimiasis based on an elevated antibody level of Paragonimiasis westermani. Although she had no medical history of allergic disorders, a pulmonary function test revealed bronchodilator reversibility. After praziquantel therapy, her symptoms, hypereosinophilia in peripheral blood, and pleural effusion were improved. A repeated pulmonary function test after praziquantel therapy showed a negative bronchodilator response. Pulmonary paragonimiasis may induce bronchodilator reversibility during the acute phase of infection.

Temporal evolution of thoracocentesis-induced changes in spirometry and respiratory muscle pressures

BACKGROUND

Several studies investigated the effects of thoracocentesis on aspects of respiratory function without generally ensuring absence of coexistent lung pathology or homogeneity in initial size of the effusion.

METHODS

We studied 90 patients aged 61.6±15.9 years (mean±SD) separated into a group A with small-sized or medium-sized effusion (A=56 patients) and a group B with large and massive one (B=34 patients). There was no significant lung lesion or cardiovascular pathology. The basic spirometric parameters and maximal respiratory pressures were recorded on three instances: just before thoracocentesis (T1), 30 min after completion of the procedure (T2) and after 48 hours (T3).

RESULTS

At T2 vs T1, groups A and B respectively presented significant change (mean±SD) (increase) in forced vital capacity (FVC) of 0.071±0.232 and 0.139±0.224 L, in forced expiratory volume in 1 s (FEV₁) of 0.127±0.231 and 0.201±0.192 L, in FEV₁/FVC of 2.8% and 4.9%, in peak expiratory flow rate (PEFR) of 0.342±0.482 and 0.383±0.425 L/s, in maximal expiratory pressure (MEP) of 0.049±0.037 and 0.049±0.039 kPa and in maximal inspiratory pressure (MIP) of 0.040±0.041 kPa only in group A while decrease in MIP with significant change of 0.055±0.051 kPa in group B. At T3 vs T2 in groups A and B, there was significant change (decrease) in FEV₁/FVC of 2.7% and 4.6% as well as significant change (increase) in MIP of 0.036±0.046 and 0.115±0.060 and in MEP of 0.049±0.043 and 0.070±0.048 kPa.

CONCLUSIONS

Thoracocentesis is associated with progressive-small relative to the volume of fluid removed-increases in lung volumes. In larger effusions at T2, a transient decrease in MIP is observed presumably due to temporary geometric distortion of the diaphragm immediately after fluid removal.

Thoracentesis

Pleural effusions are common and account for high morbidity and mortality in a range of patients. Thoracentesis can provide significant symptom relief and improvement in physiologic parameters including dyspnea, exercise, and sleep. Recent advances, including the use of ultrasound and dedicated procedural teams, have improved the safety of thoracentesis. This has allowed thoracentesis to be performed on higher-risk individuals including those with elevated bleeding risk and bilateral pleural effusions. This review will summarize recent advances in thoracentesis procedural safety, symptom relief following thoracentesis, and understanding of the physiologic basis for such improvements.