🩸 Chapter 139: Abdominal Paracentesis (Ascitic Tap)

Diagnostic & therapeutic indications · Sites (midline, left lower quadrant) · Z-track technique · Fluid analysis (SAAG, cell count, culture) · Contraindications (coagulopathy, bowel distension) · Large-volume paracentesis · Albumin infusion

🔍 Core Concepts: Abdominal Paracentesis (Ascitic Tap)

📌 Indications
Diagnostic: new ascites, suspected spontaneous bacterial peritonitis (SBP). Therapeutic: tense ascites with respiratory compromise, abdominal compartment syndrome.
📍 Insertion Sites
Midline (2 cm below umbilicus – linea alba, avascular). Left lower quadrant (5 cm superior/medial to ASIS – thinner wall). Ultrasound-guided.
🚫 Contraindications
Absolute: acute abdomen requiring surgery. Relative: coagulopathy (INR >2, platelets <20k), infection at site, distended bladder, bowel obstruction, pregnancy.
🔧 Technique
Z-track (retract skin 2 cm caudal) to prevent leak. Local anaesthesia. Advance needle until fluid flash. Catheter-over-needle or direct aspiration.
🧪 Fluid Analysis
Cell count/differential, SAAG (serum ascites albumin gradient), culture (inoculate blood culture bottles), Gram stain, LDH, glucose, cytology.
⚠️ Large-volume paracentesis (LVP)
For tense ascites with respiratory distress. Replace with albumin (8-10 g/L fluid removed) in cirrhotics to prevent post-paracentesis circulatory dysfunction (PICD).
⚡ Complications
Leak (most common), bleeding, infection, bowel perforation, hypotension (PICD), haematoma.

🩺 Stepwise Abdominal Paracentesis

1
Prepare patient & consent
Explain procedure, obtain consent. Empty bladder (reduce injury risk). Position supine with head elevated 30-45°.
2
Select site & ultrasound
Preferred sites: midline (2 cm below umbilicus) or left lower quadrant. Ultrasound to identify fluid pocket and avoid bowel/bladder.
3
Sterile prep & local anaesthesia
Chlorhexidine prep. Infiltrate lidocaine down to peritoneum (Z-track: pull skin 2 cm caudally while injecting to prevent leak).
4
Needle insertion & fluid collection
Insert needle (angiocath or paracentesis kit) with syringe. Advance until fluid flash. Collect 30-60 mL diagnostic sample. For therapeutic, connect tubing to drainage bag.
5
Send samples & post-care
Cell count (EDTA tube), SAAG (plain tube, albumin), culture (blood culture bottles at bedside), LDH, glucose, Gram stain. Apply occlusive dressing. Monitor for hypotension after large-volume paracentesis.