Long-term Effects of Accidental Dural Puncture in Patients Having Had an Epidural Blood Patch (LEAP)

Overview

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.

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.