Late septic encephalopathy and septic shock are not associated with ongoing cerebral embolism

SummaryBackgroundThe hypothesis that cerebral embolism plays no role in late septic encephalopathy and septic shock is based on indirect clinical evidence in the literature. The goal of this study was to prove the hypothesis that cerebral embolism plays no role in the pathophysiology of sepsis by direct evidence.MethodsTo examine this hypothesis, 20 patients with a late septic encephalopathy and septic shock were examined for direct evidence of ongoing cerebral embolism with transcranial Doppler for 30 min. Clinical data analysis included age, gender, cause of sepsis (gram-positive or -negative microorganisms), an index of severity of illness (the APACHE II score) and outcome (survivor/non survivor). Cerebral embolism was quantified by embolus detection software.FindingsThe study revealed no ongoing cerebral embolism during sepsis.ConclusionCerebral micro-embolism plays no role in cerebral dysfunction during sepsis. This negative finding has an important clinical repercussion, because if transcranial Doppler exams should reveal ongoing cerebral embolism in septic shock, the embolism cannot be attributed to the septic shock itself rather it would indicate for a vigorous search for an embolic source.