Nudrat Tasneem, Edgar A. Samaniego, Connie Pieper, Enrique C. Leira, Harold P. Adams, David Hasanand Santiago Ortega-Gutierrez
Department of Neurology, Stroke Division, University of Iowa Carver College of Medicine, Iowa City, IA, USA
Department of Neurosurgery, University of Iowa Carver College of Medicine, Iowa City, IA, USA
Stabilizing a patient with a brain injury doesn’t mean they are out of the woods just yet. Neurocritical care patients are at risk of developing secondary brain injury from inflammation, ischemia and edema that follows the primary injury. Recognizing secondary clinical deterioration is frequently challenging in comatose patients. Multimodality monitoring (MMM) encompasses various tools to monitor cerebral metabolism, perfusion and oxygenation aimed at detecting these changes to help modify therapies before irreversible injury sets in. Clinical presentation of acute brain injury (ABI) frequently includes a variable degree of altered mental status in conjunction with a very limited neurological exam.
This downstream injury is called Secondary BrainInjury (SBI) and it is often missed in unresponsive and sedated neurocritical patients. Cutting-edge technology now provides sophisticated tools that allow us to gather real-time integrated information of the pathophysiological processes in comatose patients. The goal of MMM is early detection of SBI by monitoring changes in physiologic parameters that reflect cell death and injury. These parameters include intracranialpressure (ICP), Cerebral Perfusion Pressure (CPP), Cerebra Blood Flow (CBF), brain tissue oxygenation, cerebral metabolism and electro cortical activity. ICP and CPP are the most commonly monitored parameters in patients with acute brain injury. Currently recommended devices include intraventricular catheter also known as External Ventricular Drainage (EVD) or intraparenchymal monitors (Natus Camino®).
Neurocritical care patients often have non-convulsive seizures, which are subclinical. The prevalence of non-convulsive seizures in patients with brain injury including TBI, SAH, ICH, and hypoxic-ischemic encephalopathy ranges from 4 to30% and is associated with secondary cerebral damage, evidenced by elevated LPR and ICP. Continuous EEG fora minimum of 48 hours is required to detect non-convulsive seizures with >90% sensitivity among comatose patients. Non-convulsive seizures are associated with increased morbidity and mortality regardless of etiology. CurrentMMMguidelines recommend EEG in all patients with ABI and unexplained altered consciousness, in patients with convulsive status epilepticus who do not return to baseline within 60 minutes after medication, during therapeutic hypothermia and within 24 hours after rewarming.
This paper discusses the use of various Multimodality Monitoring techniques including intracranial pressure, Electroencephalography, Cerebral perfusion pressure, blood flow, oxygenation and metabolism in neurocritical care patients to recognize clinical deterioration and reduce risk of brain injury.
Access the complete article
Download to read the complete article on Brain Multimodality Monitoring: A New Tool in Neurocritical Care of Comatose Patients today.