Spine subdural hematoma: a rare complication associated with vitamin K antagonist (VKA)

Flato, Uri Adrian Prync; Rheder, Paulo Sérgio; Guimarães, Helio Penna; Flato, Elias Silva; Cretella, Paulo

doi:10.1590/S0066-782X2009000100013

Abstracts

Spinal subdural hematoma (SSDH) is a rare condition, which is difficult to diagnose, related to Vitamin K Antagonist. This a case report of a life-threatening situation in a octogenarian patient with a history of recent atrial fibrillation that received K-Vitamin Antagonist (KVA) therapy. The history and the clinical assessment were normal at the admission, associated with increase in the coagulation parameters (INR >10). Twenty-four hours after the admission, the patient developed progressive tetraparesis and a Magnetic Resonance Imaging (MRI) was performed, disclosing the evidence of a SSDH (Figure 1). An emergency neurosurgical intervention was performed associated with normalization of the coagulation parameters. After the procedure, the patient presented improvement of the neurological symptoms.

Hematoma, subdural spinal; spinal cord; blood coagulation

O hematoma subdural de medula espinhal (HSDME) é uma complicação rara decorrente do uso de antagonistas de vitamina K (AVK) e de diagnostico difícil. Este artigo apresenta um caso com complicação ameaçadora à vida: um paciente octogenário portador de fibrilação atrial de início recente em uso de AVK. A história e o exame físico inicialmente se apresentavam normais, associados com a elevação dos valores de coagulograma supraterapêuticos (INR > 10). Após 24 horas da admissão hospitalar, o paciente apresentou tetraparesia progressiva, evidenciando na ressonância nuclear magnética (RNM) de medula espinhal um HSDME (Figura 1). Após reversão completa da hipocoagulação e intervenção neurocirúrgica o paciente obteve melhora do quadro neurológico.

Hematoma subdural espinal; medula espinhal; coagulação sanguínea

El hematoma subdural espinal (HSE) es una complicación rara proveniente del uso de antagonistas de vitamina K (AVK) y de diagnostico difícil. Este artículo presenta un caso con complicación amenazadora para la vida: un paciente octogenario portador de fibrilación auricular de inicio reciente, en uso de AVK. Inicialmente, la historia y el examen físico se presentaban normales, asociados a la elevación de los valores de coagulograma supra terapéuticos (INR > 10). Tras 24 horas del ingreso hospitalario, el paciente presentó tetraparesia progresiva. Al realizarse una resonancia nuclear magnética (RNM) de médula espinal, se evidenció un HSE (Figura 1). Tras reversión completa de la hipocoagulación e intervención neuroquirúrgica el paciente obtuvo mejora del cuadro neurológico.

Hematoma subdural espinal; médula espinal; coagulación sanguínea

CASE REPORT

Hospital Villa Lobos, São Paulo, SP - Brazil

Mailing address

ABSTRACT

Spinal subdural hematoma (SSDH) is a rare condition, which is difficult to diagnose, related to Vitamin K Antagonist. This a case report of a life-threatening situation in a octogenarian patient with a history of recent atrial fibrillation that received K-Vitamin Antagonist (KVA) therapy. The history and the clinical assessment were normal at the admission, associated with increase in the coagulation parameters (INR >10). Twenty-four hours after the admission, the patient developed progressive tetraparesis and a Magnetic Resonance Imaging (MRI) was performed, disclosing the evidence of a SSDH (Figure 1). An emergency neurosurgical intervention was performed associated with normalization of the coagulation parameters. After the procedure, the patient presented improvement of the neurological symptoms.

Key words: Hematoma, subdural spinal; spinal cord; blood coagulation.

Discussion

It is estimated that 2.5 million people¹ currently have atrial fibrillation in the USA, in whom treatment with vitamin K antagonists (VKA) implies in the relative decrease (RD) in cardiovascular events of 68%². With the increase in life expectancy, it is estimated that 10% of the world's population older than 80 years will present this heart arrhythmia.

Regarding the use of vitamin K antagonists (VKA), the clinical studies³ have demonstrated an incidence of major bleeding of 0.3%-0.5% a year and central nervous system bleeding of 0.2% a year. It is worth mentioning that these data were obtained from patients that were adequately managed and monitored regarding the anticoagulation parameter; in this scenario, some patients were excluded from the study: patients that abandoned the treatment during the initial study period (inclusion or Run-in phase), those excluded due to sociocultural questions, and a small number of patients in some subgroups with a high prevalence of cardioembolic complications, such as the elderly. Data from daily clinical practice, i.e., from "real-life patients", are probably higher than those previously reported; however, adequate evidence under a methodological point of view is not available and only retrospective studies with a small number of patients are considered for such. Abdelhafiz and Wheeldon⁴, in a retrospective study of patients using VKA, showed an incidence of major bleeding of around 3.4% a year, monitored in non-specialized outpatient clinics. The following are considered independent risk factors for bleeding associated to the use of VKA: intensity of the anticoagulant effect (INR >3.0), characteristics of the patient (age older than 75 yrs), use of drugs that interfere with the VKA and time of treatment. Due to the small number of octogenarian patients included in clinical studies of oral anticoagulants (OAC), this group endures reservations and suggestions of OAC with reduced therapeutic targets (INR 1.8-2.5). Its use must be based on socio-behavioral aspects and routine use of bleeding risk models⁵, to conduct the adequate therapy and decrease the risks to the patient. Recently, Hart et al⁶ carried out a randomized, double-blind study in octogenarian patients, comparing VKA aspirin and observed a decrease of 40% in ischemic cerebrovascular events associated to a similar rate of bleeding between the two groups.

The VKA management directives⁷ have been recently updated, especially regarding the use of this drug antidotes related to the patient's clinical presentation and the level of anticoagulation (Chart 1).

The complications related to this treatment can very often be devastating and perhaps, the implementation of educational measures, strategies to improve patients' adherence to VKA associated to the implementation of clinics that are specialized in anticoagulation can allow the therapeutic success as well as the decrease in severe adverse events.

The spinal subdural hematoma (SSDH)⁸ is an emergency situation and its prompt recognition and treatment are mandatory. In spite of the currently available imaging techniques, the delay in the recognition of the SSDH and the precision of the ideal diagnostic method are obstacles to be overcome. The main causes of this severe diagnosis are the use of oral anticoagulants, iatrogenic event during lumbar puncture, spinal trauma and tumors.

The clinical presentation varies from localized symptoms, vesical dysfunction, to unspecific symptoms such as lumbar pain, mimicking lumbosciatic syndrome. The extension of the hematoma, as well as its location in relation to the spinal cord, can lead to medullary compression syndrome and irreversible damage to the spinal cord, secondary to ischemia. The main factors related to irreversible spinal cord injury are: time of medullary compression (start of the symptoms > 12 hours) and the delay in the surgical treatment for decompression. The gold standard for the diagnosis of medullary structure alterations is the magnetic resonance imaging (MRI)^9,10; usually, it is impossible to differentiate between spinal subdural and epidural hematomas in their hyperacute phases (< 12 hours); however, through the multiplane reconstruction one can visualize, through sagittal slices, its entire head-caudal extension.

The therapeutic options described in the literature in cases of SSDH are: initial reversion of the precipitating cause, such as total reversion of the anticoagulation, decompressive surgical treatment (laminectomy, incision in the dura-mater and thrombus removal), percutaneous drainage and/or conservative treatment.

Conclusion

This case demonstrates the impact of hypercoagulation on an octogenarian individual, associated to a rare complication, difficult to diagnose and that requires rapid interventions. We conclude that the suspicion of medullary involvement in anticoagulated patients that present minimal neurological symptoms must be considered, particularly when safety ranges of INR values (2-3,5) are above the expected ones.

Potential Conflict of Interest

No potential conflict of interest relevant to this article was reported.

Sources of Funding

There were no external funding sources for this study.

Study Association

This study is not associated with any post-graduation program.

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