Pediatric Ascitic Tap (Paracentesis)
Pediatric Ascitic Tap (Paracentesis)
Key Points
- Diagnostic and therapeutic procedure for removal of fluid from peritoneal cavity
- Essential skill for evaluation of new-onset ascites
- Requires careful patient preparation and sterile technique
- Can be both diagnostic and therapeutic
Definition
Paracentesis is a medical procedure involving the removal of fluid from the peritoneal cavity using a needle or catheter. In pediatric patients, this procedure requires special considerations due to smaller patient size and potentially different underlying pathologies.
Primary Indications
- New-onset ascites of unknown etiology
- Suspected spontaneous bacterial peritonitis (SBP)
- Refractory ascites causing respiratory compromise
- Evaluation of suspected malignant ascites
- Therapeutic drainage in patients with tense ascites
Clinical Scenarios
- Portal hypertension secondary to liver disease
- Nephrotic syndrome with significant fluid accumulation
- Suspected tuberculosis peritonitis
- Post-operative fluid collections
- Chylous ascites
Absolute Contraindications
- Acute surgical abdomen
- Severe coagulopathy (INR > 2.0)
- Severe thrombocytopenia (platelets < 50,000)
- Local skin infection at puncture site
Relative Contraindications
- Pregnancy
- Distended bowel
- Previous abdominal surgery in proposed tap site
- Uncorrected bleeding disorders
Essential Equipment
- Sterile gloves and drapes
- Antiseptic solution (Chlorhexidine or Betadine)
- Local anesthetic (1% lidocaine with 25G needle)
- Paracentesis needle (18-22G)
- Collection tubes:
- Plain tube
- EDTA tube
- Blood culture bottles
- Drainage bags (for therapeutic tap)
- Dressing materials
Procedure Steps
- Patient Preparation
- Explain procedure to patient/parents
- Obtain informed consent
- Empty bladder before procedure
- Position patient supine with head elevated 30-45°
- Site Selection
- Left lower quadrant (preferred)
- 2-3cm medial to anterior superior iliac spine
- Avoid visible blood vessels and scars
- Sterile Technique
- Mark site and clean with antiseptic
- Apply sterile drapes
- Infiltrate with local anesthetic
- Fluid Collection
- Insert needle at 90° angle
- Aspirate fluid slowly
- Collect appropriate samples
- Remove needle and apply pressure
Post-Procedure Care
- Apply sterile dressing
- Monitor vital signs for 2 hours
- Check for complications
- Document procedure details
Immediate Complications
- Bleeding
- Bowel perforation
- Vasovagal reactions
- Pain at puncture site
Delayed Complications
- Persistent leak from puncture site
- Local infection
- Peritonitis
- Hemodynamic changes (with large volume paracentesis)
Normal Values
- Protein: < 3 g/dL
- Albumin: < 1.1 g/dL
- WBC: < 500 cells/mm³
- PMN: < 250 cells/mm³
Diagnostic Criteria for SBP
- Absolute PMN count ≥ 250 cells/mm³
- Positive bacterial culture
Other Important Tests
- Serum-ascites albumin gradient (SAAG)
- Cytology
- Gram stain
- Culture and sensitivity
- Adenosine deaminase (for TB)
