Long-term Effects of Accidental Dural Puncture in Patients Having Had an Epidural Blood Patch (LEAP)
Condition: Post-dural Puncture Headache; Post-dural Puncture Backache
MeSH terms: Post-Dural Puncture Headache; Headache; Wounds and Injuries
Study type: Observational

Summary: 
      Accidental dural puncture (ADP) during placement of an epidural catheter for anesthesia and
      analgesia is a well known complication. Previous studies have found audiometric deterioration
      following ADP. Epidural blood patch (EBP) is a common method for treating postural headache
      in patients with accidental dural puncture. In most cases, one-two patches are needed for
      successful management. Long-term effects of EBP on the incidence of backache, headache and
      early audiometric deterioration are few or non-existant. The present study aims to determine
      the long-term sequelae of EDP in parturients who had ADP and were treated with an EBP during
      the years 2005 - 2011.
    

Detailed description: 
      A major risk with epidural analgesia (EDA) is accidental dural puncture (ADP). ADP occurs in
      approximately 1% of all pregnant women receiving EDA in connection with childbirth. Postdural
      puncture headache (PDPH) is the most common complication after ADP and affects approximately
      86% of all mothers with ADP. Headache after ADP may be severe and sometimes affects the
      interaction between the newborn baby and the mother. The headaches are orthostatic which
      makes the patient bedridden, and are associated with symptoms such as nausea, vomiting,
      tinnitus and hearing changes. The symptoms are thought to represent leakage of cerebrospinal
      fluid (CSF), which in turn leads to reduced CSF volume and intracranial hypotension. These
      volume changes lead to traction of pain-sensitive intracranial structures. There are no
      studies in the literature that have either confirmed or visualized CSF leakage after ADP. The
      diagnosis of PDPH is solely based on clinical examination. There are over 50 different
      treatment options for PDPH. These treatments can be divided into conservative or invasive.
      Among others, the conservative treatment options include bed rest, caffeine and various pain
      medications. Several studies have shown the absence of a definite and curative effect of
      these treatment options. The most widely used invasive method for management of PDPH is
      epidural blood patch (EBP). EBP was first introduced in the 60's by applying three ml of the
      patients' own blood epidurally. Over the years, this volume has increased to at least 15-20
      ml on the basis of case reports and studies with small number of participants and without any
      definite scientific evidence. However, EBP should not be applied sooner than 24 hours after
      the onset of accidental dura puncture, as the risk of failure is higher. Further studies are
      required in the literature to confirm the efficacy of EBP.

      Additionally, the long term effects of EBP remain either unknown or vaguely understood. Are
      we treating an acute symptom with an invasive method, not knowing the long term sequelae?
      Since audiometric changes are known to result following ADP, can these changes persist over a
      long period of time? Therefore, we are interested in assessing the long term effects of EBP
      on backache, headache and audiometric changes in parturients who delivered during the years
      2005 - 2011.
    

Observational model: Case-Control
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        Women who had delivered during the years 2005 - 2011. Experimental group: 60 patients who
        had an accidental dura puncture during labour or caesarean section and developed post-dura
        puncture headache and required an epidural blood patch would constitute the experimental
        group Contro group: 600 patients, identical to the above except that they had no dura
        puncture and therefore no post-dural puncture headache
      
Keywords: Post-dural puncture headache; epidural blood patch; labour analgesia; epidural analgesia