Bilateral interhemispheric subdural hematoma after accidental lumbar puncture and epidural blood patch

Abstract

We read with interest the article of Demetriades et al. [1] concerning bilateral interhemispheric subdural hematoma after inadvertent lumbar puncture in a parturient. I congratulate them on the presentation of the case. Likewise, I would like to address the issue of the performing epidural blood patch (EBP) in the presence of subdural intracranial hematoma (SIH). The authors recommended EBP as one of the treatments of this complication. We should say it is risky to make this claim. Subdural intracranial hematoma is a very rare, but lifethreatening complication of accidental dural puncture caused by cerebral hypotension associated with excessive traction on the bridging veins secondary to cerebrospinal fluid (CSF) leak through a dural hole [2]. The incidence of this problem is unknown. Factors that increase the imbalance between production and loss of CSF (e.g., peripartum dehydration, labor contractions, bearing-down efforts, obstetric bleeding, postpartum dieresis or early ambulation) can increase its incidence in obstetric patients. Initial clinical presentation of SIH is most often an atypical headache (absence of postural component, persistence for more than 7 days, and unresponsiveness to analgesic therapy). Sometimes, the headache is accompanied by the signs of increased intracranial pressure or mass effect on the brain parenchyma such as vomiting, seizure activity, and altered level of consciousness, psychiatric or focal motor and sensory disturbances. Post dural puncture headache (PDPH) may initially mimic or unmask these symptoms, further complicating the diagnosis. A typical PDPH is exacerbated in the upright position and relieved by the horizontal position. When conservative management of PDPH is unsatisfactory or headache intensity is severe, an EBP is frequently performed. EBP relieves the headache restoring intracranial CSF volume and pressure by two basic mechanisms [2]. First, the blood injected clot and seal the dural perforation, preventing further CSF leak. Second, the volume injected into the epidural space increases epidural pressure and compresses the dura elevating adjacent subarachnoid pressure and, through continuity, the intracranial pressure. This increase in pressure is dependent on the rate and volume of injection and level injected. Thus, early EBP may decrease the risk of subdural bleeding by preventing a fall in CSF volume and subsequent intracranial hypotension. However, when EBP is performed in the presence of intracranial hemorrhage, rebound intracranial hypertension and neurological deterioration can result [2–6]. An early differential diagnosis is needed to provide the adequate treatment, which may influence the prognosis of this complication. EBP should not be performing when there is suspicion or evidence of the existence of SIH.