NASHVILLE—Patients with stroke who have not improved after receiving t-PA can benefit from treatment in the ICU for various complications resulting from large infarcts, according to Daryl R. Gress, MD, who addressed the Society of Critical Care Medicine’s 38th Critical Care Congress.
“Most strokes are probably never seen in the ICU, and they are more optimally managed in stroke units,” said Dr. Gress, Associate Professor of Neurology and Director of Neurocritical Care at the University of Virginia in Charlottesville. “In critical care, we are really talking about individuals with either severe deficits and high NIH Stroke Scale scores or those in which mental status is compromised. We also see those postrevascularization.”
Stroke Care in the ICU
A decline in mental status is the most common reason that patients with stroke are admitted into the ICU, along with the need for intubation, largely for airway protection, according to Dr. Gress. “By the time that one needs to intubate, you are dealing with a very serious problem,” he said.
Neurologic deterioration among patients with large ischemic strokes should be monitored closely, advised Dr. Gress. “Almost always as the neurologic exam deteriorates, it triggers the need for imaging and head CT, in part, to exclude hemorrhage, particularly in the postthrombolytic patients. If there’s hemorrhage, one has to take some effort to reverse the associated coagulopathy, but it is not easily done…. In many of these situations, large hemorrhage following t-PA has a poor prognosis irrespective of surgical intervention.”
Intracranial pressure issues, such as maintaining cerebral perfusion, are also key elements of ICU care in patients with stroke. For monitoring neurologic deterioration, “intracranial pressure is only a fair marker of tissue shift and is not a perfect monitoring device for this,” noted Dr. Gress. “If you don’t have intracranial pressure and those people are awake and you can follow the exam, you clearly are watching to try to keep the exam from deteriorating. If they get sleepier, if the ipsilateral pupil starts to get bigger, you know that you are beginning to get on that slippery slope into the herniation syndrome, and it’s time to be careful. Hyperventilation is a fairly short strategy for an hour or two and does not serve much purpose in long-term intracranial pressure management.”
Osmotic therapy is a useful tool, although “medical management via osmotic therapy may well not be strong or potent enough for us to overcome the physiology of that infarct,” commented Dr. Gress. Mannitol and hypertonic saline are two options that clinicians can use. “You want to achieve a hyperosmolar state that is a little bit higher than your current osmolality,” he noted.
“Medical management is really limited in these [cases], and it may well be that you do all your best and people are continuing to deteriorate,” Dr. Gress continued. “[Patients with] these large middle cerebral infarcts have a pretty poor prognosis. If you look at what people define as large middle cerebral artery infarcts needing intubation and ICU care, the mortality is clearly in excess of 50%.... There may be a need for something beyond medical management in that case, and it is one of those situations in which surgical intervention clearly can be considered.”
Surgical Intervention
Decompressive hemicraniectomy can be used to help control intracranial pressure and tissue shift related to herniation, according to Dr. Gress. Surgical decompression is a fairly common tool for cerebellar infarcts and hemorrhage, although it is less commonly accepted with extensive middle cerebral artery infarcts, he noted. “For massive middle cerebral artery infarcts, the natural history is bad outcome in a high percentage—[ranging from 50% to 90%]—depending on how you define that population,” said Dr. Gress. Unpublished data from the Head First trial revealed that 26 patients had an improvement in survival from 54% to 73%. European trials such as DESTINY, DECIMAL, and HAMLET have reported a benefit in survival ranging from 29% to 78%, with no increased risk of severe disability. “Age is one of the biggest determinants in outcome following these [interventions], in part, because age is a big determinant in one’s ability to recover from a given infarct,” he noted.
The timing of surgical intervention has been debated among clinicians. “I think most of us prefer to wait until it’s pretty clear that things are going to be a problem, but not so long that it becomes too late to get any benefit out of it,” commented Dr. Gress. “If one is following intracranial pressure or the neurologic exam and considering hemicraniectomy, it’s good to have you, the neurosurgeon, and the family understand at what point that decision is going to be translated into action.