ICP Monitoring

After studying this topic the learner will be able to: - Explain the Monro-Kellie doctrine and why a small added volume can produce a large pressure rise once compliance is exhausted. - Calculate cerebral perfusion pressure (CPP) from mean arterial pressure (MAP) and intracranial pressure (ICP), and state the target range and the ICP treatment threshold used in severe traumatic brain injury (TBI) guidance. - Compare an external ventricular drain (EVD) with an intraparenchymal monitor, and say what each can and cannot do. - Level, zero and clamp an EVD correctly under the unit's policy and the surgeon's orders, and predict the error produced by a wrongly placed transducer. - Distinguish early signs of intracranial hypertension from severe intracranial hypertension and impending herniation, and match the urgency of the response to the stage (Cushing's triad is a late sign). - Monitor a patient receiving osmotherapy (mannitol or hypertonic saline) and know which values are reported before the next dose. - Escalate a deteriorating patient promptly, and say who decides on each intervention.