Senator Mark Kirk is the junior Senator from Illinois. He currently holds President Obama’s old seat which he won in a special election in 2010 to replace Roland Burris.
He has apparently suffered a large right sided, non-dominant hemisphere middle cerebral artery stroke, potentially after a carotid artery dissection on that side. And he’s now undergone a decompressive craniectomy on the right from the late edema suffered with such a large stroke.
Dr. Fessler said the stroke “will affect his ability to move his left arm, possibly his left leg and possibly will involve some facial paralysis. Fortunately, the stroke was not on the left side of his brain, in which case it would affect his ability to speak, understand and think.”
Chances for a full mental recovery were “good” but chances for a full physical recovery were “not great,” Fessler said.
The doctor said he was hopeful that, after rehabilitation at an acute care facility, Kirk would regain the use of his left leg, but said prospects for regaining the full use of his left arm were “very difficult.”
He said recovery is a matter of weeks or months — “it’s not going to be days.” Kirk’s relative youth and good physical shape are positives, Fessler said, and he expects Kirk could return to “a very vibrant life.”
I’m sure they’ve been aggressive considering his age and functional status, not to mention his stature. But to feel the need to go ahead with a craniectomy following a stroke implies a large area of ischemia. Decompressive craniectomy for large middle cerebral artery strokes is not terribly uncommon and the popularity for it has probably grown over the decades. As one, admittedly international paper, describes it.
Decompressive craniotomy in the setting of acute brain swelling from massive MCA infarct is a life saving procedure. It should be considered in patients with initial good GCS, who are deteriorating in neurological status. With the team effort of neurologist and neurosurgeons these cases have good outcome contrary to the natural history of disease…Thus an ideal candidate for decompressive craniotomy is the victim who is young, with no risk factors, who presents early and has nondominant, middle cerebral artery territory infarct, with a reasonable Glasgow Coma Scale with no (or) early signs of herniation. The key for success of these cases of large MCA infarcts is early detection. Clinicians should concentrate on formulating newer clinical, radiological and technical protocols to detect the suitable patients at an early stage.
Certainly from what we know Senator Kirk appears to be an ideal candidate. From the description of his possible long term deficits he appears to have had a large non-dominant hemisphere middle cerebral artery stroke. He is relatively young and fit. And, as The Chicago Tribune describes it, he presented with a relatively good exam and deteriorated quickly.
My thoughts and prayers are with him and his family. He has a long road ahead of him.
Background
The Corticosteroid Randomization After Significant Head injury (CRASH) trail was a huge international double blinded randomized trial which collected a huge cohort of patients suffering traumatic brain injuries with GCS less than 14 on presentation and presenting within 8 hours of injury and randomizing them to receiving a 48 hour course of methylprednisolone versus a placebo. The final results were published in The Lancet in 2005.
As if that was not enough the database collected for the study was the largest, most complete database of patients following head injury in the world. It included more than 10,000 patients from across the world and had a very high rate of follow up through 6 months. This database was used to create a prognostic model for outcome following head injury. Published in the British Medical Journal in 2008 the CRASH model has become one of more widely cited outcome prediction models in clinical practice when dealing with patients with head injury.
MRC CRASH Trial Contributors. “Predicting Outcome after Traumatic Brain Injury: Practical Prognostic Models Based on Large Cohort of International Patients.” Bmj 336.7641 (2008): 425-29
The original paper is available for free as full text on the BMJ website.
Design
This was a retrospective review of outcome of a large cohort of patients.
The database included 10,008 patients originally collected for the CRASH Trial. The database contained information on a large number of variables but the prognostic model focused on 9 initial variables: age, sex, etiology of the trauma, time on presentation, GCS on presentation, pupil reactivity on presentation, results of CT scan, whether the patient had a major extracranial injury, level of per capita income in the country where the injury occured.
They prognosed to two outcomes death within 14 days of injury or outcome at 6 months as measured by the Glasgow Outcome Score which they dicotomized into favorable outcomes (moderate disability or good recovery) and unfavorable outcomes (dead, vegetative state or severe disability).
They developed two models with the above variables: a basic model which excluded the findings on CT imaging and a CT model which included them.
Internally they validated the two models using bootstrap resampling. And then they externally validated the model using the 8000+ patients suffering head injury included in the independent International Mission for Prognosis And Clinical Trial (IMPACT) database. The original description of the IMPACT Trial is here on PubMed.
Results
All nine of the variables included in the final two models independently had strong associations with both outcomes (death at 14 days and poor outcome at 6 months). The table showing the odds ratios for each variable can be found here.
Regression of outcome of model including CT scan findings
After this internal validation they compared their model to outcomes observed in the IMPACT Trial blinded.
CRASH model predictions of outcomes for patients enrolled in IMPACT versus variable outcome
It showed good discrimination in the external validation with a C-score of 0.77 (essentially the area under the reciever operator curve). And for the basic model and the CT model in high income countries there was very good calibration by the Hosmer-Lemeshow test.
The authors have published a calculator with predictive outcomes based on the regression. The calculator gives odds for death at 14 days and poor outcomes at 6 months based on both models.
Critique
The sample size of this study is legitimate and one of the stronger points of it. The database appears well maintained and exceptionaly complete considering the number of patients and the challenges of coordinating data collection across continents. Looking at the demographics it appears relatively representative. As well the follow up to 6 months is a legitimate end point for the goals of the study and the sample included a great number of patients to that end point.
The outcomes measured to seem clinically relevant and were set prior to the models being designed. The variables included in the regressions as well have previously been validated at predicting outcomes in other smaller studies and are clinically readily available.
The study found no difference in outcomes based on treatment, including the randomization to steroids or placebo in the trial itself, which is an important consideration.
It is true the CT model in particular showed comparatively poor calibration for patients injured in lower income countries. Even there however the Hosmer-Lemeshow measure isn’t particularly off. The smaller sample size of patients with readily available CT imaging findings may in part explain such.
The major critiques otherwise of the study seem to be those available to be leveled at all published prognostic models. Generalization is a difficult thing especially to individual anecdotal scenarios. However for a study with in vivo data from patients seemingly encountered early following representative head injury and undergoing real world salvage attempts the model shows remarkable, if not perfect, calibration and discrimination.
Conclusion
The models developed from the CRASH trial are very likely the “best” available prognostic models for predicting outcome early after traumatic head injury. The calculator published by the authors appears a valid and useful tool for any health care provider encountering significant neurotrauma. A “better” prognostic model for the prediction of outcome early after head injury seems unlikely.
A traumatic subdural with a pretty good shift deteriorates on his transfer from some rural area, gets to your hospital as a GCS of 7 and needs to go to the operating room emergently. His next of kin rode on the transport to your hospital. Other family members are en route by car but are some distance out.
You try to consent his next of kin using phrases like ‘emergency,’ ‘right now,’ ‘life and death’. The response is a lot of waffling, a request to wait until the rest of the family gets to the hospital, and calls to those same family members seeking advice.
I seem to have run into the above, or the equivalent, several times over my still young intern year. Not every night or every week, but a few times. Too many times.
I understand such situations are incredibly stressful for those presented with a decision for an emergent procedure (or not) for a loved one. I understand a lot of information is presented to them in a short period and they’re asked to digest it under stress and make one of the most important decisions of their lives.
I’m not sure it excuses trying to skirt the responsibility.
The most frustrating instances involve those legally responsible asking you as the provider to seek the opinion of other family members and to have them decide.
“Oh, I just don’t know! Can you call his sister and have her decide?”
“I’m happy to talk to her and anyone else in the family, but this is something I really need consent from you for.”
Admittedly it could be me. I don’t think so however. I think I present the situation generally with the proper sense of urgency and yet lay out the decision to be made and the options and the consequences of each option in a pretty down to earth and understandable way. The few times I’ve run into this, others – my residents, fellows, faculty – who have come along to talk to the family after me have had the same problem.
True, maybe as the first to attempt consent I’ve spoiled the whole pot for all who follow. More likely the commitment and responsibility owed to a loved one breaks down under the spotlight of the situation for some.
Decisions under time pressure, with limited information, with a loved one at stake are incredibly difficult and I try to check my frustration. However, a sense of responsibility is just sometimes lacking from those asked to choose to either put the pen to the consent form or to refuse to put the pen to the consent form.
