Cough During Pleural Effusion Drainage in Dialysis Patients

Mechanism and Clinical Significance

The American Thoracic Society suggests that cough during fluid removal indicates excessive negative pleural pressure and impending re-expansion pulmonary edema (RPO), requiring immediate cessation of drainage regardless of volume removed 1, 2, 4
Rapid lung re-expansion creates mechanical stress on pulmonary vasculature, triggering cough reflexes as pleural pressure drops precipitously below -20 cm H₂O 1, 4
Vascular stretching and reperfusion injury during re-expansion stimulates irritant receptors in the airways, manifesting as persistent cough 1
The development of cough signals that safe drainage limits have been exceeded, even if the absolute volume drained seems modest 2, 3, 4

The British Thoracic Society recommends draining no more than 1-1.5 liters at one time, or slow drainage to approximately 500 ml/hour if continuing beyond this threshold 2, 3, 4
In patients without contralateral mediastinal shift, remove only small volumes as they have increased likelihood of precipitous pleural pressure falls 1, 4
Continue drainage only if pleural pressure remains above -20 cm H₂O 1, 4
Stop immediately if end-expiratory pleural pressure falls below -20 cm H₂O, regardless of volume removed 4

Dialysis patients have multiple pre-existing causes of chronic cough that complicate assessment, including fluid overload, ACE inhibitors, and GERD (especially in peritoneal dialysis patients) 5, 6, 7, 8
Peritoneal dialysis patients have 3-fold higher risk of chronic cough (22% vs 7% in hemodialysis) primarily due to gastroesophageal reflux from increased intraperitoneal pressure 5, 6, 7, 8
The American College of Chest Physicians recommends distinguishing between pre-existing chronic cough from dialysis-related causes and new-onset cough during drainage, which is a procedural complication requiring immediate cessation 1, 2, 3, 4, 5, 6, 7, 8

Do not continue drainage to reach a volume target if cough develops, as symptom development mandates immediate cessation regardless of volume drained 1, 2, 3, 4
Do not drain rapidly without monitoring, as RPO can occur from rapid removal even if absolute volume is modest 1, 4
Do not ignore the warning signs (cough, chest pain, dyspnea) as these indicate dangerous negative pleural pressures that can lead to life-threatening RPO 1, 2, 3, 4
Do not apply excessive suction; if suction is needed, use high-volume, low-pressure systems with gradual increment to maximum -20 cm H₂O 2, 3, 4
Do not assume all cough in dialysis patients is benign; evaluate for pulmonary edema from fluid overload, which can be life-threatening and requires optimization of dialysis ultrafiltration rather than thoracentesis 8