Light at the end of the Tunnel-post Hypoxic Myoclonic Seizures-lance Adams Syndrome

INTRODUCTION: Neurological outcomes after successful cardio-pulmonary resuscitation are often difficult to predict. Although Lance-Adams syndrome (LAS) is a rare occurrence, it is common in cardiac arrest survivors where the cause is respiratory arrest. Less than 150 cases have been reported in the medical literature till date. Early diagnosis and treatment of LAS is associated with better functional outcome. We report a case of 69-year-old survivor of respiratory arrest who developed myoclonic jerks few hours after the event which we initially thought of as myoclonic status epilepticus (MSE) but was found to have LAS. CASE REPORT/CASE SERIES: 69-year-old male patient with history of left MCA infarct, presented with COPD-acute exacerbation with type-2 respiratory failure. He was initially given a NIV trial and but due to worsening of respiratory acidosis he was intubated. His type 2 respiratory failure resolved and after successful spontaneous breathing trial patient was extubated and put on NIV. Patient developed cardiac arrest later, for which cardiopulmonary resuscitation was initiated. The return of spontaneous circulation was achieved following 6 cycles and was intubated. GCS score was E1VTM1 post arrest. He developed myoclonic jerks few hours post arrest, hence was started on with Inj. levetiracetam and infusion of midazolam and propofol. Suspecting hypoxic ischemic encephalopathy, EEG and brain imaging were done. EEG study showed-dys II generalized, moderate encephalopathy (suppressed background theta rhythm). No evidence of acute infarct/bleed or hypoxic ischemic encephalopathy was found in brain imaging. Sedative infusions were stopped as EEG wasn't suggestive of myoclonic status epilepticus. Dose of levetiracetam was hiked and oral clonazepam and valproate was added. Reassessment of sensorium showed an improvement from baseline E1VTM1 to E3VTM6. Whenever midazolam infusion was stopped, he was awake, intermittently alert, following commands, visual tracking bilaterally with myoclonic jerks (right hand, left foot) appearing intermittently mainly on stimulation. Thus, based on clinical findings and after ruling out myoclonic status epilepticus on EEG and acute infarcts or hemorrhage in imaging, a diagnosis of Lance -Adams syndrome was made. The frequency of myoclonic jerks subsided during the ICU stay. Patient was tracheostomized and weaned to bipap later. DISCUSSIONS: Lance-Adams syndrome is a rare but important complication of hypoxic brain injuries. It occurs due to disruptions of circuitry between subcortical and cortical structures while sparing majority of the cortex.(1) It is often confused with post-hypoxic myoclonus status epilepticus which has a worser prognosis. CONCLUSION: It is important to differentiate LAS from MSE since the former is associated with better neurological outcome. Clinicians should supplement their clinical findings with imaging and EEG to provide the most accurate diagnosis and prognosis.