Continuation Of a Study to Investigate the Effect of Thoracocentesis on Neural Respiratory Drive in Pleural Effusion

The aim of this study is to better understand the relationship between pleural effusions and breathlessness in patients with unilateral pleural effusions and breathlessness who require pleural fluid removal for its management.

Inclusion Criteria: * Age 18 years or above * Has a unilateral pleural effusion AND 1. require thoracocentesis OR 2. chest drain insertion (main study only) OR 3. has an IPC in situ (main study only) Exclusion Criteria: * Inability to consent * Any contraindications to the proposed pleural procedure * Haemodynamic or clinical instability that precludes from the safe completion of required pre-procedural measurements * Inability to identify surface landmarks for surface EMG electrode placement * Past medical history of diaphragmatic paralysis (diaphragm sub study only)