Dados do Trabalho

Título

Reversible electroencephalographic burst-suppression pattern due to baclofen intoxication: a case report

Apresentação do caso

A 51-year-old female patient with generalized spasticity, managed with baclofen 80 mg/day, was referred to the hospital owing to increased drowsiness for four days. On admission to the ICU, she was intubated; midazolam and fentanyl were started at usual sedative doses. Urosepsis was diagnosed, warranting antibiotic therapy. Underwent a head CT scan, which showed no abnormalities. As the renal function declined, intermittent hemodialysis was started on the 12th day, and sedatives were discontinued on the 18th day; baclofen posology was maintained. A first EEG was performed on the 21st day, showing a diffuse slowing of brain rhythms in the theta range. In the following days, she presented with a reduced level of consciousness, bilateral mydriasis, and loss of the oculocephalic reflex, with preservation of the corneal-palpebral reflex and respiratory drive. A second CT scan was performed, with no relevant findings. On the 25th day, a second EEG showed a burst-suppression pattern, and a hypothesis of baclofen intoxication was considered, and the drug was discontinued; that was followed by significant improvement in the electroencephalographic pattern and some improvement in the level of consciousness and cranial nerve function.

Discussão

Baclofen is a muscle relaxant drug commonly used to treat spasticity. Intoxication can result in deep coma and may mimic brain death. Our patient developed a clinical-electroencephalographic syndrome compatible with this hypothesis, as there were no other plausible etiologies. Other factors that favored the diagnosis were: the presence of acute kidney injury, resulting in increased bioavailability of the drug; resolution of the burst-suppression pattern and improvement of neurological function after its discontinuation; the absence of structural abnormalities. Baclofen intoxication is related to a variety of electroencephalographic abnormalities, such as slowing of background activity, slow waves with triphasic morphology and generalized rhythmic delta activity. The burst-suppression pattern related to the drug is a rare condition, with only nine cases described so far.

Comentários finais

A burst-suppression pattern with coma may represent a rare electroclinical manifestation of baclofen overdose. Once its use is widespread in clinical practice, and because this complication is potentially reversible, the condition warrants promptly recognition.

Área

NEUROFISIOLOGIA CLÍNICA