Therapeutic abdominal paracentesis (ascitic drain) [advanced]

Before you start

Indications: large volume ascites causing respiratory compromise or abdominal pain/pressure

Relative contraindications: coagulopathy (INR >1.4, platelets <50, therapeutic anticoagulant <24 hours, clopidogrel <7days); pregnancy; distended bowel (obstruction/ileus); organomegaly; distended bladder

Introduction

• Wash hands, Introduce self, Patients name & DOB & wrist band, Explain procedure and get written consent
  • Risks: pain; bleeding; infection (peritonitis); damage to local structures (including bowel perforation); paracentesis leak
  • Ask patient to empty their bladder prior to procedure
• **Check patients clotting screen, platelet count and if they have been on an therapeutic anticoagulant/clopidogrel**
• Ensure assistant is available
• Examine patient and tap out ascites
• Use ultrasound to confirm the presence/location of ascites, check the depth of the abdominal wall and mark the spot pre-procedure

Preparation part

• Wash hands and apply apron
• Clean a trolley
• Gather equipment onto bottom of trolley (think through what you need in order)

• Walk to patient
• Wash hands
• Open sterile pack to form a sterile field on the top of the trolley
• Open packets (without touching the instruments themselves) and drop sterile instruments neatly into the sterile field
• Pick up waste bag from sterile pack without touching anything else and stick to side of trolley

Patient part

Positioning and exposure

• Position patient lying supine in bed with head of bed elevated (aids fluid accumulation in lower abdomen)
• Expose patient’s abdomen

If the insertion point has not already been marked using ultrasound…

• Locate insertion point:
  • Traditionally in the right iliac fossa (approximately 5cm above and up to 5cm medial to the right ASIS) – right side is strongly preferred because patients may have splenomegaly and splenic varices on left
  • Tap out ascites and confirm flank dullness at intended insertion point
• Use different site if there is overlying infection
• Mark insertion point with a skin pen/indentation

Preparation

• Wash hands
• Apply sterile gloves using sterile technique (open pack on a side surface)
• Sterilize area
  • Work from middle outwards in one spiral motion (using cleansing snap-sponge)
  • Repeat with second cleansing snap-sponge
  • Discard used snap-sponges as they are no longer sterile, but note all equipment used after this (including all needles) can be returned to the sterile field after use
  • Apply the sterile drape over the patient’s body so that the hole is in the correct place to allow access to the insertion site (or apply 2-3 drapes centred around exposed insertion site if no holes)
• Anaesthetise tract
  • Ask assistant to snap open lidocaine bottle and hold open upside-down
  • Draw up lidocaine using drawing-up needle on 10 ml syringe and expel any air
  • Change to the orange needle and insert at an acute angle to form a single subcutaneous bleb around insertion site in order to anaesthetise the skin
  • Change to the green needle and insert perpendicular to the skin to anaesthetise the insertion tract
    • This is done by instilling lidocaine in small increments of increasing depth
    • Always aspirate when advancing the needle (so you know when you get to the peritoneal cavity) and aspirate before injecting lidocaine (to check you are not in a vessel)
    • When fluid is aspirated, remove needle and do not advance further
• Now wait 1 minute for the anaesthetic to work, while you prepare the equipment and put in order:
  • Scalpel: expel blade
  • Needle/catheter preparation: attach 20ml syringe to end of needle; close 3-way tap; remove catheter sheath
  • Blue valve cap
  • Extension tubing

Paracentesis

• Make a 2mm scalpel incision through the anaesthetised skin
• Insert needle perpendicular to the skin into the same tract, aspirating during infiltration
• When fluid is aspirated, advance 5-10mm further to ensure the tip of the catheter enters the peritoneal cavity (not just the tip of the needle) – safety needle kits may also click as they enter the peritoneal cavity
• Holding the needle still, undo the blue valve and advance the catheter off the end of the needle until the flange touches the skin
• Remove needle
• Attach the blue valve cap to the blue valve at end of the catheter
• Secure catheter flange with dressing
• Attach extension tubing to 3-way tap, then attach drainage bag
• Open 3-way tap and ensure drainage
• IF SAMPLES ARE REQUIRED: attach the 20ml syringe used during insertion to the side port of the 3-way tap and aspirate 20ml for samples, then replace bung

Finally

• Secure tubing

To complete

• Confirm it works
• Thank patient and cover them
• Decant and send ascitic fluid samples if collected
• Bin waste and gloves, dispose of sharps safely, clean trolley and wash hands
• Fluid replacement: give 100ml 20% human albumin solution following every 2L ascites drained in cirrhotic patients; otherwise determine need for crystalloid fluids clinically
• Drainage rate: free drainage of up to 5L over first 4 hours, then up to 1L/h (if hypotensive – limit to 0.5L/h throughout)
• Fully document procedure in patients notes
• Other notes
  • Drain can be left in for up to 6 hours (risk of infection if left longer, especially for cirrhotic patients)
  • If ascitic fluid is still draining through tract after removal, attach stoma bag