Disautonomias

539

SHORT REPORT

Gabapentin in the management of dysautonomia following severe traumatic brain injury: a case series
Ian J Baguley, Roxana E Heriseanu, Joseph A Gurka, Annette Nordenbo, Ian D Cameron
................................................................................................................................... J Neurol Neurosurg Psychiatry 2007;78:539–541. doi:10.1136/jnnp.2006.096388

The pharmacological management of dysautonomia, otherwise known as autonomic storms, following acute neurological insults, is problematic and remains poorly researched. This paper presents six subjects with dysautonomia following extremely severe traumatic brain injury where gabapentin controlled paroxysmal autonomic changes and posturing in the early post-acute phasefollowing limited success with conventional medication regimens. In two subjects, other medications were reduced or ceased without a recurrence of symptoms. It is proposed that medications that can block or minimise abnormal afferent stimuli may represent a better option for dysautonomia management than drugs which increase inhibition of efferent pathways. Potential mechanisms for these effects arediscussed.

evidence, is intravenous morphine, midazolam, drugs with sympathetic activity (alpha agonists and some beta blockers), bromocriptine and intrathecal baclofen.6 The efficacy of gabapentin in the management of dysautonomia has not been reported to date.

CASE REPORTS
Subjects were males in their late teens or early twenties who survived extremely severe TBI following high speed motorvehicle crashes. The injury suffered by subject No 3 was complicated by prehospital cerebral hypoxia. Subjects were transferred to inpatient rehabilitation with dysautonomic features in evidence (diagnosed according to previously published criteria1). All subjects were minimally responsive at the time of admission to rehabilitation and had spastic tetraparesis. The findings presented in this reportfollowed the successful reduction of pain and spasticity in two subjects with late stage dysautonomic changes following severe TBI (subject Nos 1 and 2 in table 1). In these subjects, dysautonomic paroxysms had largely settled and gabapentin was commenced to treat presumed neuropathic pain syndromes. This reduced paroxysmal spasticity and pain in subject No 1 and improved spasticity and posturing insubject No 2 with gabapentin doses of 300 mg twice daily and 600 mg twice daily, respectively. Subject No 3 Subject No 3 displayed dysautonomic paroxysms with abnormal posturing and agitation during episodes. Bromocriptine was initiated (5 mg three times daily, increasing to 10 mg three times daily) with minimal effect. He was commenced on regular oral morphine, titrated to minimise the degree ofsedation and to reduce, but not stop, dysautonomic episodes. An intrathecal baclofen (ITB) pump was implanted 2 months after admission, reaching a stable dose of 370 mg daily. This markedly decreased tone and dysautonomic features while at rest and oral morphine was ceased. He continued to experience dysautonomic episodes when stimulated, particularly with muscle stretches and ranging of joints.A presumed neuropathic pain syndrome was treated with gabapentin 300 mg three times daily, 4 months after admission. This immediately decreased his dysautonomic paroxysms and apparent pain, with improved sleep and reduced agitation. Regular morphine was weaned off and then ceased without recurrence of symptoms and the ITB dose was weaned to 225 mg/day without an increase in spasticity. Subject No4 Subject No 4 developed severe dysautonomia in the ICU and was treated with beta blockers (50 mg metoprolol four times daily) and intravenous morphine. Multiple severe
Abbreviations: ANS, autonomic nervous system; ITB, intrathecal baclofen; TBI, traumatic brain injury www.jnnp.com

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ysautonomia, otherwise known as ‘‘autonomic storm’’, is a distinct clinical syndrome affecting a subgroup...