Bilateral Sphenopalatine Ganglion Block With or Without Bilateral Greater Occipital Nerve Block for Treatment of Obstetric Post-Dural Puncture Headache
Condition: Post-Dural Puncture Headache
MeSH terms: Post-Dural Puncture Headache; Headache
Study type: Interventional

Summary: 
      Post-dural puncture headache is a common complication, following neuraxial techniques. The
      obstetric population is particularly prone to PDPH. Therefore, treatment of PDPH is a key
      issue in obstetric anesthesia. Conservative treatment for PDPH includes adequate hydration,
      systemic analgesia with paracetamol and non-steroidal anti-inflammatory drugs and increased
      caffeine intake, as well as bed rest. If these measures are unsuccessful, the gold standard
      for the treatment of PDPH is the epidural blood patch which is an invasive technique.

      The use of nerve blocks for treating headache symptoms are well known techniques that have
      been previously used for managing some specific types of chronic headache such as
      cervicogenic headache, cluster headache, migraine, and occipital neuralgia and there are some
      recently published studies reporting that these blocks may be beneficial in treating PDPH and
      the available evidence although showing improvements in the visual analogue (VAS) scores and
      a reduced number of patients requiring an epidural blood patch, but it is still poor.

      Less invasive techniques such as SPG block and GONB are attractive therapeutic options which
      may eliminate the need for EBP in obstetric patients suffering from PDPH. Up to the best of
      our knowledge this is the first randomized trial to investigate the analgesic efficacy of
      adding SPG block either alone or in combination with GONB to PDPH treatment.
    

Detailed description: 
      Post-dural puncture headache (PDPH) is a relatively common complication following dural
      puncture which is more frequently noted in parturients undergoing cesarean section (CS) under
      neuraxial anesthesia. The mechanism of nociception in PDPH is still indistinct. However, it
      is thought to be related to the decrease in intracranial pressure caused by the cerebrospinal
      fluid (CSF) leak through the dural defect leading to a downward pull of intracranial
      nociceptive structures which is further exacerbated by compensatory cerebral vasodilation.
      Managing Post-dural Puncture Headache is a challenge for most anesthesiologists as the gold
      standard and definitive treatment; epidural blood patch (EBP) itself can lead to inadvertent
      dural puncture that caused the complication in the first place. Medical and conservative
      management of PDPH may not provide symptomatic relief and anesthesiologists are on a constant
      lookout for techniques that can provide immediate and sustained relief from this debilitating
      complication.

      The use of regional techniques and nerve blocks for the treatment of headache symptoms are
      well known techniques. The transnasal sphenopalatine ganglion (SPG) block which is an easy
      block that requires minimal training was shown to be helpful in the PDPH treatment with
      promising results. The SPG surrounded by mucous membrane within the posterior nasal
      turbinate, is a parasympathetic ganglion of cranial nerve (CN) VII which mediates
      intracranial vasodilation. The role of this block in PDPH management may be due to the
      vasoconstriction resulting from the parasympathetic block. Additionally, its relationship to
      the fifth cranial nerve (trigeminal nerve) may simultaneously relieve the frontal headache.

      Another regional technique that can be used is the Greater Occipital Nerve Block (GONB) that
      has been previously used for managing some specific types of chronic headache such as
      cervicogenic headache, cluster headache, migraine, and occipital neuralgia and there are some
      recently published studies reporting that GONB may have a beneficial role in PDPH management.
      In addition, it is a superficial block which can be done at the patient's bedside under
      ultrasound guidance. The greater occipital nerve is the main sensory nerve of the occipital
      region that arises from the dorsal ramus of cervical spinal nerve II. The neuromodulation
      effect together with decreased central sensitivity resulting from meningial and paraspinal
      muscles irritation as well as blocking the spinal cord dorsal horn afferent fibers may
      explain the role of GONB in relieving PDPH symptoms. Moreover, the sensitive neurons of the
      upper cervical cord are close to the trigeminal caudal nucleus. Therefore, its afferences may
      also be blocked with this technique.

      The available evidence of these blocks for treating PDPH although showing improvements in the
      visual analogue (VAS) scores and a reduced number of patients requiring an epidural blood
      patch, but it is still poor. Moreover, there are some clinical scenarios in which the patient
      may refuse treatment with the epidural blood patch, or there may be a contraindication for
      its use. Hence, we hypothesized those obstetric patients who are particularly prone to PDPH
      may get benefit from these less invasive techniques and that these blocks may be added to the
      treatment of patients suffering from PDPH in order to avoid the invasive EBP.
    

Intervention name(s): Bilateral transnasal sphenopalatine ganglion block.; Bilateral ultrasound guided greater occipital nerve block.
Intervention type(s): Procedure; Procedure
Intervention description(s): SPG block will be performed with the patient in supine position using cotton-tipped plastic hollow applicator inserted in the nose with the swab soaked in 1.5 ml 10%lignocaine. The applicator will be inserted parallel to the floor of the nose until resistance encountered. The swab will be rested in the pterygopalatine fossa superior to the middle turbinate and removed after 10 min. This procedure will be repeated in the other nostril too.; GONB will be performed with the patients lying in prone position using high frequency (6-13 MHz) probe of Siemens Acuson X300 machine placed in transverse orientation lateral to external occipital protuberance parallel to the superior nuchal line to detect occipital artery where the nerve is located medial to it 1.5inch; then 20 gauge needle will be inserted out of plane to avoid vascular injury. 4 ml of treatment solution containing 2.5 mg/ml bupivacaine and 1 mg/ml dexamethasone (prepared by adding 2 ml bupivacaine 0.5% + 1 ml dexamethasone + 1 ml saline) will be injected on each side.
Other intervention name(s): (SPG) block.; (GONB).
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment