Blow to the Head : DJ Part Two
DJ’s recount of what he does remember, as disjointed as it is, is pretty typical for someone with some amnesia around the time of the blow to the head. Looking back on it with a skeptical eye, as too often is done, is that there is apparent logic to what he does remember versus what he doesn’t. Further, what he remembers is complicated by the years of focus on these events, trying to sort out what is a pure memory and what is reconstructed.
One could argue that this inquiry in DJ’s case is irrelevant because we do not have to deduct that he had a TBI, because he ultimately became comatose, for two weeks after the blow to the head. Yet, one of the methodologies often used to measure the legitimacy of Mild Traumatic Brain Injury symptoms, is to compare them to severe TBI symptoms. With DJ as an example, as there can be no controversy about the severity of his brain injury, what we learn about some of the things he can remember during such period, does shed light on amnesia, for less severe TBI, caused by a blow to the head.
First, it highlights that the timeline for determining retrograde versus anterograde amnesia, may actually be two timelines. The first timeline begins the moment when he struck his head, say 4:30 p.m. The second timeline begins point at his neurological function deteriorates to the point that an ambulance was called, say10:30 p.m. He has very little retrograde amnesia before the first neurological insult, the blow to the head. However, he has considerable retrograde amnesia before the second neurological insult, the increase in intracranial pressure.
One could argue that the amnesia between 4:30 and 10:30 is anterograde amnesia to event one, yet I am not sure that is correct. It seems more probable that it is the beginning of anterograde amnesia for the second neurological insult, the increase in intracranial pressure caused by the blow to the head.
One would think as important as amnesia is to prognosis, that these kind of issues would be delineated in the treatises – textbooks on neurology and brain injury. I have never found such a discussion in those texts, perhaps because historically so many people with rapidly forming ICP events like DJ, never lived to be questioned about the problems.
The bigger problem is that there is no systematic treatment of amnesia inquiries. I wrote this initially before I looked at DJ’s records for the first 16 hours after his injury. At that time I predicted that there would be no contemporaneous inquiry as to what he remembers between 4:30 p.m. and 10:30 p.m. Upon reflection, I thought this question important enough that I obtained DJ’s permission to review and comment on his records for that period. Here is what I found:
- At 12:22 a.m., roughtly 8 hours after his injury, on his initial assessment, his chief complaint is “neck pain, for only one hour.”
- At 12:44 a.m., head pain is added to complaints. At such time he is “Level of Consciousness: Awake, alert, oriented – person, place, time.” He is sent for CT.
- At 1:58, he vomited in the examining room.
- At 3:05 Diagnosis: “subarachnoid hemorrhage.”
Despite the 3 a.m.the next day diagnosis, there is no documentation that he was ever asked anything about his memory from 4:35 p.m. on the day of injury to 3 a.m. the next day. Presumably, based upon the later coma and diagnosis of subarachnoid hemorrhage, his neurologic function was rapidly decreasing. Yet, the documentation of this most critical measure of that decrease, the ability to form new memories, is missing.
The other thing of significance in what DJ does remember (to the degree we can assume that these are first hand recollections) is that the more exciting the event – other than the blow to the head itself – the more he seems to remember. This would be consistent with a view that adrenaline/emotional content improves memory function, during an amnestic period.
So I remember the storm coming in, and I remember it being very violent. To this day I can see the lightening underneath the 405 Bridge going into Cape Canaveral Air Station.
The contemporaneous amnesia inquiry in DJ’s case was quickly made a low priority by the diagnosis of subarachnoid hemorrhage. Yet that doesn’t reduce my criticism of the emergency room staff for not making and documenting these inquiries. The potential for a permanent life altering TBI would have still existed, had the CT scan not documented the hemorrhage due to his blow to the head. But then the presence of amnesia could have been a critical diagnostic finding.