What is the key question?

• Are indwelling pleural catheters (IPC) superior to repeated therapeutic thoracentesis (TT) in the management of patients with refractory transudative pleural effusions?

What is the bottom line?

• The REDUCE study is an open-label multicenter randomized controlled trial where individuals with symptomatic pleural effusion due to either heart, liver or renal failure were assigned in a 1:1 ratio to either an IPC (intervention, n=33) or a TT (standard care, n=35). IPCs were drained at least three times a week for the first two weeks, and subsequently at a frequency considered appropriate by clinicians and patients. Patients receiving standard care had a first TT removing up to 1.5L in a hospital procedure room then had TT as needed. The primary outcome was mean daily breathlessness score over 12 weeks from randomization, measured using visual analogue scale (VAS) scores.
• The study found no significant difference between treatments in the primary outcome analysis, with mean breathless score over the 12-week study period of 39.7mm (SD 29.4) in the IPC arm and 45.0 mm (SD 26.1) in the TT arm (mean difference -2.9mm, 95% CI -16.1 to 10.3; p=0.67). Subgroup analysis did not show any significant differences in treatment effects between different causes of effusion (heart/renal versus liver) or size of effusion (≥ ½ or ½ < hemithorax). There was no significant difference between treatments in mean breathlessness scores over the first 7 or 28 days. There was no difference in mean number of bed days, care visits or pleurodesis success rates during the study period. There was no statistical difference in EQ-5D scores between groups at baseline or at the subsequent monthly visits.
• Significantly more patients in the IPC arm (59%) had at least one adverse event compared to the TT arm (37%), p=0.04. Most had minimal impact on the patient and the risk of infective complications was low with only one case of IPC related infection and none in the HH cohort.

Why read on?

• We learn from this study that IPCs do not offer greater control of breathlessness than repeated TT for recurrent non-malignant effusion, despite large difference in drainage volumes. IPC may have a role in selected patients who do not tolerate repeated TT, prefer a treatment strategy deliverable at home or in whom repeated interruption of anticoagulant therapy is undesirable.