Paracentesis (ascitic tap / drain)

Category: Kidney & Dialysis Procedures · All kidney & dialysis procedures

What it is

Paracentesis removes fluid that has collected in the abdomen (ascites) using a needle or a temporary drain, usually guided by ultrasound. A small sample (diagnostic tap) helps find the cause; a large-volume drain relieves breathlessness and discomfort from a tense abdomen.

Why it is done

Ascites most often relates to liver disease, but also heart failure, kidney problems (including nephrotic syndrome and dialysis patients), infection and cancer. The tap tests the fluid for infection, cells and chemistry to guide treatment.

How to prepare

An ultrasound confirms the fluid pocket and safe site. Blood tests including clotting and platelets are checked; blood thinners are reviewed. For large-volume drainage, albumin (a protein fluid) is often given through a drip to protect circulation and kidney function as the fluid comes off.

What happens during the procedure

After numbing the skin, the needle or drain is inserted into the abdomen and fluid flows to a collection bag. A diagnostic sample takes minutes; a large-volume drain is clamped intermittently and typically runs over several hours under observation with blood pressure checks.

Afterwards — recovery & results

Most people feel more comfortable and breathe easier straight away. The drain is removed the same day in most cases. Fluid often re-accumulates if the cause persists — your team manages this with salt restriction, diuretics or repeat drainage plans. Seek help for fever, abdominal pain, leakage or dizziness afterwards.

Risks & considerations

Risks include leakage from the puncture site, bleeding, infection of the fluid, low blood pressure and kidney strain after very large removals (reduced by albumin cover and controlled rates), and rarely injury to bowel. Ultrasound guidance has improved safety.

Frequently asked questions

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