Noninvasive Intracranial Pressure Morphology in Acute Liver Failure: Pre- and Post-orthotopic Liver Transplantation
Johnny Dang1, Davis Ewbank1, Adam Barron1, Catherine Hassett1
1Cleveland Clinic
Objective:
We present a case of time-lapsed non-invasive intracranial pressure (nICP) monitoring sessions used to help guide the management of a patient with acute on chronic liver failure (ACLF) before and after orthotopic liver transplantation (OLT).
Background:
Elevated levels of ammonia in the body can result in cerebral edema, posing a significant risk of life- threatening intracranial pressure (ICP). Several methods utilize ICP monitoring to obtain cerebral compliance estimations; however, current strategies require invasive placement. The mechanical extensometer (Brain4Care) offers a non-invasive alternative for assessing ICP waveform parameters, including Time to Peak (TTP) and the P2:P1 ratio. Estimations of cerebral compliance with P2:P1 ratio of ≥1.4 and TTP ≥0.2 seconds have been validated to predict intracranial hypertension.
Results:
A 27-year-old male presented in ACLF (MELD-Na 34) due to Wilson’s Disease and was transferred for OLT consideration. He developed progressive encephalopathy that led to eventual intubation. Non- contrasted CT Head revealed diffuse cerebral edema. Arterial ammonia peaked at 106 prior to initiation of continuous renal replacement therapy. Subsequent pre-OLT monitoring sessions depicted deteriorating nICP waveform trends with peak P2:P1 ratio of 1.36 (95% CI 1.15 – 1.60) and TTP of 0.23 seconds (95% CI 0.22, 0.24) correlating with evolving cerebral edema on serial CT imaging. The neurological ICU team stabilized the patient by optimizing cerebral perfusion pressure and initiating hyperosmolar therapy. The patient underwent successful OLT, and post-operative day 1 monitoring revealed normalization of nICP waveform with a P2/P1 ratio of 0.86 (95% CI 0.84, 0.89) and TTP of 0.10 seconds (95% CI 0.10, 0.11). These trends correlated with the patient’s improving metal status leading to eventual discharge to acute rehabilitation.
Conclusions:
nICP monitoring is feasible for the liver failure patient during OLT consideration. Future studies are needed to determine independent prognostic thresholds for nICP waveform in the liver failure population.