Acute liver failure (ALF) often leads to death, but how? In many, if not most cases, the cause is cerebral edema and its sequelae like hypoxic injury and brainstem herniation. The presence of cerebral edema requires timely diagnosis because effective management may be critical for survival.
The diagnosis of cerebral edema should be entertained after the onset of hepatic encephalopathy (typically Grade III or IV). Systemic hypertension, bradycardia and altered respirations, known as Cushing’s triad, may be absent in many cases, and less obvious signs like increased muscle tone, hyperreflexia or altered pupillary responsiveness are present.
The appropriate time to order a diagnostic head CT is not an easy choice to make; these patients often have elevated intracranial pressure (ICP) and the agitation associated with transport to and from radiology and tranfer to the CT scanner and back may exacerbate these pressures. If Grade of encephalopathy is high, and suspicions are even higher, a diagnostic CT is appropriate. In this image, notice the loss of sulci and the blurred distinction between grey and white matter.