Prediction of Post-dural Puncture Headache in Parturients Undergoing Elective Caesarean Section
Condition: Postdural Puncture Headache
MeSH terms: Post-Dural Puncture Headache; Headache
Study type: Observational [Patient Registry]

Summary: 
      The parturients are at particular risk of post dural puncture headache (PDPH) because of
      their sex, young age, and the widespread application of spinal and epidural anesthesia. PDPH
      has a negative impact on quality of life, patient satisfaction, the postpartum experience
      with the mother's inability to bond with and care for her baby and it increases the economic
      burden associated with childbirth. Therefore, it is necessary to prevent or decrease its
      incidence and severity.

      TCD enables measurement of the blood flow velocity in intracranial arteries and its
      parameters are affected by both fluctuations in intracranial pressure and changes in cerebral
      vessel diameters. The possibility of equipment mobilization, the opportunity of repeated
      bedside technique together with the noninvasive nature, makes TCD measurements attractive in
      the attempt to estimate CBF and offers potential application to predict and follow patients
      with PDPH.
    

Detailed description: 
      PDPH is described as severe "searing and spreading like hot metal" distributed over the
      occipital and frontal areas radiating to the neck and shoulders. 90% of headache will occur
      within three days of the procedure, and 66% within the first 48 hours. The PDPH rarely
      develops between 5 and 14 days after the technique however it may immediately occur after
      dural puncture but it is rare and should pay attention of the physician to alternative
      causes. The pain is increased by head movement, upright posture and relieved by lying down.
      It resolves either spontaneously within 7 days or within 48 h after effective treatment which
      is usually consists of fluid therapy, analgesics, sumatriptan and caffeine. Epidural blood
      patch remained the gold standard therapy but it is an invasive technique.

      The exact etiology of PDPH is unknown; there is two hypothesis attempts to explain the cause.
      First it's known that dural tear leads to cerebrospinal fluid (CSF) leak and decreased volume
      of CSF result in intracranial hypotension which cause on pain sensitive intracranial
      structures that become stretched when assuming upright position result in pain. Second,
      intracranial volume is constant and equal to the sum of intracranial blood, CSF, and brain
      matter. After loss of CSF a compensatory reflex vasodilatation occur in the same pain
      sensitive blood vessels and this result in pain.

      The association of common risk factors like female gender, particularly females during
      pregnancy, age groups of 20 - 40 years, a prior history of chronic headache, and a lower body
      mass index expose the patient to PDPH. The identification of factors that predict the
      likelihood of PDPH is important so that measures can be taken to minimize this painful
      complication resulting from spinal anesthesia.

      Transcranial Doppler ultrasound (TCD) is a portable, safe, noninvasive and real-time tool for
      assessing intracranial blood hemodynamics. The first description of the technique was by Rune
      Aaslid in early 20th century and it has gained increasing acceptance as an accurate
      diagnostic and therapeutic tool in both cerebrovascular disease and neurocritical care. TCD
      enables measurement of the blood flow velocity in intracranial arteries and several Studies
      have shown that its parameters are affected by both fluctuations in intracranial pressure and
      changes in cerebral vessel diameters. So, as PDPH may be resulted from significant changes in
      cerebral blood flow, it could be visualized by TCD.

      The possibility of equipment mobilization, the opportunity of repeated bedside technique
      together with the noninvasive nature, makes TCD measurements attractive in the attempt to
      estimate CBF and offers potential application to predict and follow patients with PDPH.
    

Intervention name(s): Performance of the transcranial Doppler (TCD)
Intervention type(s): Device
Intervention description(s): Within 24 hour before the operation, TCD is performed using Siemens Acuson X300 machine with ultrasound frequency is 1 - 5 MHz probe to measure Mean Velocity and Pulsatility Index in the right middle cerebral artery.postoperatively, TCD study is performed twice at 24h and 48h after spinal anesthesia. For 5 days postoperatively, the Patients are assessed clinically for the occurrence of headache. Patients who developed PDPH will be identified and their pre and post puncture measurements will be compared with the corresponding measurements of PDPH free patients.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Pregnant female undergoing Elective caesarean section under spinal anesthesia.