Indications

• Clinical symptoms of increased intracranial pressure.  Symptoms may include
  • Apnoea, bradycardia
  • Poor feeding
  • Somnolence
  • Hypotonia

• Ultrasound evidence of progressive ventriculomegaly

Contraindications

• Low circulating blood volume
• Cellulitis or abrasion over reservoir site
• Sunken fontanelle

Aims of Treatment

• To decrease progressive ventriculomegaly
• To allow head growth at a rate of <1cm per week

Equipment

• Chlorhexidine or Povidine-Iodine skin preparation solution
• 25 gauge butterfly needle (may need 23g if CSF tenacious)
• Standard infant lumbar puncture set
• Sterile drapes to allow for maintenance of a sterile field

Precautions

1. Maintain strict asepsis.
2. Monitor and correct serum electrolytes every other day if more than 10ml removed daily.
3. Be prepared to provide rapid fluid replacement should infant not tolerate large volumes removed. Replace fluid removed with intravenous normal saline.
4. If skin breakdown occurs, select insertion site away from broken area.
5. Do not place IVs on same side of scalp.

Technique

1. Consider the use of Sucrose for analgesia if the baby meets the criteria.
2. Place the infant with head in neutral position in anticipation of a 20 to 25 minute procedure.
3. Cut any long hair that interferes with the surgical area but do not shave operative area.
4. Wearing sterile gloves, clean skin with chlorhexidine (or Povidine-Iodine) over the reservoir and a surrounding circle of skin with a diameter of 4cm.
   • Use light but firm contact.
   • Allow to dry (2 minutes).
5. Position sterile drape to maintain a sterile field.
6. Cut the hub from the butterfly tubing.
7. Insert butterfly needle through skin just into reservoir bladder.

• Select an insertion site different from the one most recently used.
• Angle needle at 30 to 45 degrees from the skin.
• The base of the reservoir is metal so cannot be punctured.

7. Allow the cerebrospinal fluid (CSF) to drip into the CSF collection bottles.  As the pressure reduces, the flow rate will reduce accordingly and this should be used as a guide for to when cease the procedure.
8. Limit total volume of CSF drained at each tapping to no more than 30ml or 15ml/kg (whichever is less).
   • The initial puncture should not exceed 10ml in volume and can be increased on sequential taps at a rate of not more than 5ml/day.
9. Sample CSF for culture, cell count, glucose and protein every three days.
   • If fluid is blood-stained (from old haemorrhage), biochemical analysis may not be helpful.
   • Culture dark fluid every three days.
10. Remove needle and hold firm pressure for 2 minutes or until CSF leakage from skin stops.
11. Repeat drainage at intervals dictated by clinical response +/or ultrasound markers. Repeat once a day but as often as twice daily. Aim to improve daily volume sufficient to prevent progressive ventriculomegaly.
    • The volume taken off each day should result in initial concavity of the fontanelle, with some overlapping of the cranial sutures.
    • If the sutures are still overlapping and the fontanelle concave the following day, the interval between aspirations should be lengthened appropriately.
12. Follow response with cranial ultrasound scans.

Reservoirs are seldom removed even if they are no longer needed.

Complications

• Local skin breakdown
• Hypovolaemia
• Hypoproteinaemia
• Hyponatraemia (check electrolytes every 2-3 days)
• Wound or reservoir infection
• CSF leak from puncture site
• Obstruction of ventricular catheter
• Ventriculitis
• May precipitate further haemorrhage if large amounts of CSF removed

References