Postdural Puncture Headache

Definition & Pathophysiology - Headache Horror

• Definition: Postural headache, typically bilateral, fronto-occipital. Onset usually 24-72h post-dural puncture.
• Incidence: Higher in obstetric patients. ↑ with larger needle size & cutting needles (vs. pencil-point).
• Pathophysiology: CSF leakage → ↓ CSF volume & pressure.
  • Brain sag → traction on pain-sensitive structures (meninges, vessels, nerves).
  • Compensatory cerebral vasodilation.
  • Monro-Kellie doctrine: ↓CSF volume → intracranial hypotension.

⭐ Classic PDPH is postural, worsening on sitting/standing and relieved by lying flat. oka

Risk Factors - Who Gets Hit?

• Patient Factors:
  • Younger age, female sex, pregnancy (all ↑ risk)
  • Prior PDPH, low BMI (both ↑ risk)
  • Connective tissue disorders (e.g., Marfan) (↑ risk)
• Procedural Factors:
  • Needle: ↑ gauge (e.g., 22G), cutting tip (Quincke) vs. ↓ gauge, pencil-point (Sprotte, Whitacre)
    • 📌 Mnemonic: "SPiN" - Sprotte Pencil-point is Non-cutting (↓ PDPH)
  • Bevel (cutting needles): Perpendicular to dural fibers (↑ risk) vs. parallel (↓ risk)
  • Multiple attempts, operator inexperience (both ↑ risk)
  • Loss of resistance: Air vs. saline (air ↑ risk? - controversial)

⭐ Use of smaller gauge, non-cutting (pencil-point) needles (e.g., Sprotte, Whitacre) significantly reduces PDPH incidence.

Clinical Features & Diagnosis - Spotting the Villain

⭐ Hallmark: Postural nature (worsens upright within 15-30 min, relieved supine within 15-30 min).

• Key Symptoms: 📌 POSTURAl H:
  • Postural, Occipital/frontal
  • Stiff neck, Tinnitus
  • Upright worsening, Recumbent relief
  • Associated (Nausea/Vomiting, photophobia, phonophobia)
  • Lightheadedness, Headache (often bilateral, throbbing/dull).
• Onset: Typically 24-72h post-puncture. Duration: Self-limiting (days to 2 weeks).
• Diagnosis: IHS criteria (history of dural puncture, characteristic postural headache, specific timing).
• Key Differentials: Migraine, tension headache, meningitis, sinusitis, pre-eclampsia headache, Cerebral Venous Thrombosis (CVT).
• Red Flags: Fever, focal neurological deficits, non-postural nature, sudden severe onset, altered sensorium.

Prevention Strategies - Dodging the Doom

• Procedural (📌 PREVENT):

  • Pencil-point/atraumatic needles (e.g., Sprotte, Whitacre).

  • Re-insert stylet before withdrawal.

  • Experienced operator; limit attempts.

  • Vigilant bevel: For cutting needles, orient parallel to dural fibres.

  • Effective (smallest) gauge (e.g., 25-27G Sprotte).

  • No multiple attempts.

  • Technique: Median/paramedian approach.

  ⭐ Orienting the bevel of a cutting needle parallel to the longitudinal dural fibres is a key preventive measure if such a needle is used.

• Patient Positioning: Post-puncture position lacks strong evidence for prevention.
• Prophylaxis:
  • Routine Epidural Blood Patch (EBP): Not generally recommended.
  • Fluids: Maintain hydration; limited prevention evidence.
  • Drugs (caffeine, cosyntropin, sumatriptan): Evidence lacking/controversial for prevention.

Management Options - Taming the Pain

• Conservative (First-line): 📌 Mnemonic: "B-HAC"
  • Bed rest (supine position).
  • Hydration (oral/IV).
  • Analgesics (simple): Paracetamol, NSAIDs.
  • Caffeine: Oral 300-500mg; IV 500mg (caffeine sodium benzoate).
• Pharmacological (Limited/Equivocal Evidence; Not First-Line):
  • Gabapentin, hydrocortisone, theophylline, sumatriptan.
• Invasive Procedures:
  • Epidural Blood Patch (EBP):

    ⭐ Epidural Blood Patch (EBP) using 15-20 mL of autologous blood is the gold standard treatment for severe or persistent PDPH.

    • Technique: Aseptic injection into epidural space (at/below puncture level).
    • Success rate: >90%.
    • Complications: Backache (common), repeat PDPH.
  • Sphenopalatine Ganglion Block (SPGB): Emerging option.

High‑Yield Points - ⚡ Biggest Takeaways

• PDPH is a postural headache (worse upright, relieved supine) after neuraxial block, due to CSF leakage.
• Onset typically 24-48 hours post-dural puncture, often fronto-occipital.
• Key risk factors: large-bore cutting needles, young age, female sex, pregnancy, multiple attempts.
• Prevention: Use small-gauge, pencil-point needles (e.g., Sprotte, Whitacre).
• Conservative management: Bed rest, hydration, analgesics, caffeine.
• Epidural Blood Patch (EBP) is the gold standard treatment for severe or refractory PDPH.
• Associated symptoms: Nausea, neck stiffness, photophobia, tinnitus may occur.