Treatment approaches in posthypoxic myoclonus: A narrative review with expert opinion

Acute posthypoxic myoclonus (PHM) is a neurological complication that typically emerges within 12-48 h following cardiac arrest, often in comatose patients. It can present as generalized, multifocal, or focal myoclonus and has traditionally been associated with poor prognosis. There are currently no standardized guidelines for its management, and prognostic outcomes remain variable. This review synthesizes the available evidence on clinical features, pathophysiology, diagnostic approach, and treatment of acute PHM. We reviewed 21 studies on PHM. Most patients experienced poor outcomes, including high rates of mortality or progression to persistent vegetative state, although a minority achieved recovery. Treatment remains largely empirical and variable, with benzodiazepines and antiseizure medications (e.g., levetiracetam, valproate, clonazepam, perampanel) being commonly used. No therapeutic intervention has consistently demonstrated improved long-term neurological outcomes. We propose a possible treatment algorithm for PHM. Acute PHM is a clinically heterogeneous disorder with significant diagnostic and therapeutic challenges. Future research should focus on refining diagnostic criteria and identifying targeted therapies to improve outcomes in this often-fatal condition.