Coma can be caused by diffuse injury or dysfunction of the brain’s cerebral cortex or a by a lesion affecting the reticular activating system in the brain stem. A comatose patient is unable to consciously feel, speak, hear, or move.
Brain death is a very severe form of coma with complete loss of brain function. Once this has occurred, the affected patient is legally dead even though the heart, circulation and lungs may still be supported by artificial means. Patients classified as brain-dead can have their organs surgically removed for organ donation.
A patient with locked in syndrome can appear like they are comatose because they can’t move or speak, but they are aware and alert. However, they can usually blink or move their eyes, and may be able to establish communication with others in this way.
There are numerous reported cases of patients with locked in syndrome after strokes or head trauma being misdiagnosed as comatose or even brain dead, some narrowly avoiding having their organs harvested.
If you ever suspect a comatose patient may actually be locked in, you can try to establish communication with eye blinks, or get an EEG which (unlike coma) will be normal and reactive in locked in syndrome.
Patients with locked in syndrome can regain some quality of life:
This plight was made famous in the movie “The Diving Bell And The Butterfly” which was based on a memoir written by journalist Jean-Dominique Bauby.
We are trying to do a better job educating our patients about the warning signs of stroke, and that if they think they might be having a stroke they should act FAST and call 911 to get to the ER as soon as possible.
However, despite these efforts only 5% of US stroke patients get to the ER in time to receive clot busting therapy to treat their stroke. Furthermore, the quicker the drug is given, the better the outcome, TIME IS BRAIN!
We would like to see patients getting treated within one hour of the onset of their stroke, but because of the time it takes to get to the hospital and get evaluated in the ER this is rarely possible.
A pilot study in Texas is looking at getting stroke therapy administered faster by bringing the ER to the stroke patient.
The project brings a mobile CT scanner and a stroke neurologist (via telemedicine) to the patient in a specially equipped ambulance. The investigators hope to see stroke patients getting treated faster and improved outcomes.
Here’s an illustrative example from a conversation with FD, an elderly woman who had had a right hemispheric stroke one week before, leaving her paralyzed on the left side and confined to a wheelchair:
How are you feeling today?
FD: I’ve got a headache. You know, doctor, I’ve had a stroke so they brought me to the hospital.
Can you walk?
FD: Yes (FD had been in a wheelchair for the past week, and cannot walk)
Mrs D, hold out your hands. Can you move your hands?
Can you use your right hand?
Can you use your left hand?
Are both hands equally strong?
FD: Yes, of course they are equally strong.
Mrs D, point to me with your left hand.
FD: (Her hand lays paralyzed in front of her).
Mrs D, are you pointing to my nose?
Can you see it pointing?
FD: Yes, it is about 2 inches from your nose.
Mrs D, can you clap?
FD: Yes, of course I can clap.
Mrs D, will you clap for me?
FD: (She proceeded to make clapping movements with her right hand, as if clapping with an imaginary hand near the midline)
Are you clapping?
FD: Yes, I am clapping.
He described two patients with left hemiplegia who didn’t know they were paralyzed. The word comes from the Greek words nosos, “disease”, and gnosis, “knowledge”.
Affected patients deny their deficit, and overestimate their abilities, they state that they are capable of moving their paralyzed limb and that they are not different than normal people.
Their false belief of normality persists despite logical arguments and contradictory evidence – they may even produce bizarre explanations to defend their convictions.
If they admit any impairments, they will attribute them to other causes (i.e. arthritis, tiredness, etc.).
But, this syndrome is not only seen with hemiplegia.
Visual anosognosia or Anton-Babinski syndrome is a rare neurological condition related to cortical blindness. Affected patients deny their blindness and affirm adamantly that they are capable of seeing. The clinical presentation includes confabulations – instead of admitting blindness, they will make up answers when asked about what they see.
Mr Magoo is a great TV example of Anton’s syndrome – unaware of his loss of vision, he misinterprets and confabulates his way into trouble.
Anosognosia may occur as part of receptive or Wernicke’s aphasia – affected patients cannot monitor and correct their own speech errors and may appear angry and frustrated when the person they are speaking to fails to understand them.
Watch this lecture, by Dr V. S. Ramachandran for more information on this fascinating syndrome:
Posted by Sanya Naware MSIV, Drexel University College of Medicine
What would it feel like to only perceive one half of the world around you?
For patients with hemispatial neglect, this is an everyday reality. Hemispatial neglect or hemineglect is a condition in which damage to one hemisphere of the brain causes a lack of awareness of one contralateral side of space. It is most often a lesion of the right posterior parietal cortex affecting the contralateral side of the body. The person is unable to recognize stimuli or process them on the affected side. Left neglect is more common than right neglect because the right hemisphere is able to compensate for the loss of left hemispheric function.
Because these patients only perceive one side, they only draw what we know to be half of an image as seen in the video and image below:
Lisa Genova, a neuroscientist, expertly describes the daily challenges of living with neglect in her book Left Neglected. It is a difficult condition to imagine and this book does a wonderful job of explaining the realities and frustrations of the patient and her family.
The main character, Sarah Nickerson, suffers a traumatic brain injury in a car crash. When she wakes up, everyone around her realizes that she ignores the left side of everything. Whether it is a clock, a painting, or a room around her, she is not able to recognize the left side of anything. While she is able to feel the left side of her body, she has to focus on the fact that she has a left side in order to control her left leg and walk. In fact, when she first sees her left arm, she states that it feels like it belongs to another person, a problem called somatoparaphrenia. While eating, she only eats the food on the right side of her tray. She frequently bumps into objects on the left side of her body because she is unaware of their presence.
Sarah’s story is optimistic as her therapist and family use certain tricks to help her adjust. Some of these methods include placing bright orange tape on the left side of things around their home, using a ruler to guide her to the left side of the page, and wearing shiny jewelry on her left hand to attract attention to it.
Genova ends her book by endorsing the New England Handicapped Sports Association (NEHSA), an organization of volunteers who help people like Sarah find some independence and confidence.
Click here to find out more about right hemispheric brain damage from NEHSA.
Atrial fibrillation (AF) is a major risk factor for TIA and Stroke.
It is estimated that AF accounts for >20% of all strokes.
Current guidelines recommend anticoagulation for all patients with AF, even paroxysmal (intermittent) AF:
1. If they have had a prior TIA or stroke, or
2. If they have two or more of the following risk factors: (1) age > 75 years, (2) history of hypertension, (3) diabetes mellitus, and (4) moderately or severely impaired left ventricular systolic function and/or heart failure.
Your risk of stroke is much higher than your bleeding risk, right?
Many AF patients don’t get anticoagulants because they are considered a fall risk. If you had AF and need anticoagulation, you would have to fall more than 300 times a year for the harm from the falls to outweigh the benefits of anticoagulation.
Despite these guidelines, recent studies have shown that:
1. Less than half of AF patients with a high stroke risk receive anticoagulants.
2. Even less patients with paroxysmal (intermittent) AF than those with permanent AF receive anticoagulants (31 vs 49%), even though the stroke risk is the same in both groups.
3. Too few patients with new onset AF are started on anticoagulants (only 52%).
We need to do better.
Click here to download a booklet about AF and stroke.
Click here to download a worksheet that you and your doctor can use to decide if anticoagulation is right for you.
We have urged you to call 911, and get to the hospital by Ambulance.
Certified stroke centers, like Monmouth Medical Center, have established protocols to get brain scans and blood work done as quickly as possible.
But what about if the Neurologist can’t get to the hospital quickly enough?
Suppose it’s late in the evening on July 4th, and the Neurologist gets stuck in traffic driving to the hospital.
You’re sitting in the emergency room with a stroke losing precious minutes.
Teleneurology allows the Neurologist to use a secure video conferencing system to examine and counsel an emergency room patient from wherever he or she may be:
Monmouth Medical Center is currently investing in telemedicine and teleneurology to improve patient care.
Watch this space for more information!
We have already blogged about acute stroke, thrombolytic therapy with t-PA, and the importance of getting to the hospital right away for early treatment.
However, even now that t-PA can be administered to most stroke patients within 4.5hrs since the onset of their symptoms, only around 5% of acute stroke patients receive the clot busting drug in the USA, more (7-8%) at certified stroke centers.
The #1 reason for not receiving t-PA is missing the time window for safe administration.
The drug must be administered within 4.5hrs (or 3hrs for some patients) since the onset of stroke symptoms in order for the benefits of the drug to exceed the risk.
Why don’t stroke patients get to the hospital in time?
Uncertain time of stroke onset.
In many cases, stroke happens during sleep, patients go to bed normal and wake up many hours later with a stroke.
We don’t know exactly what time the stroke occurred, and we have to go by the time when they were last known to be normal, which often put them outside that 3-4.5hr window.
Lack of knowledge.
However, there are still many patients who could get to the hospital in time to receive t-PA but don’t.
This is a failure of public education.
Studies have shown that as many as 1/3 of people surveyed cannot name a single symptom of stroke, and that 1/10 of people surveyed are not aware there is a time sensitive treatment available.
Only 2/3 stoke patients choose to call 911 and come to the hospital by ambulance – those that do are 50% more likely to get t-PA.
This is the reason for the ad campaigns like the AHA’s “act FAST” and “Time is brain”.
Even if they do get to the ED in time, most stroke patients still don’t get t-PA
Only 1/3 of acute stroke patients who do get to the hospital in time get t-PA!
Many have a definite contraindication, like taking blood thinners or having had recent major surgery, that does make the treatment too risky. These are a subset of stroke patients who should be considered for interventional procedures to directly retrieve blood clot from the cerebral arteries at comprehensive stroke centers.
However, as many as a 1/3 of acute stroke patients seen within that 3-4.5hr time window do not receive t-PA because their neurologic deficit is considered to be “too mild or rapidly reversing”. Obviously, this is a statement that is so hard to define, and yet still considered by many physicians to be contraindication to the use of the drug.
Many of us would argue that to the patient, there is no such thing as a “mild” stroke.
Some affected patients just get a quick screening examination lying on a gurney, and are quickly dismissed as having had “mild stroke” even though they can’t stand and walk because this was never tested.
Our own research from our certified stroke center at Monmouth Medical Center has corroborated these concerns:
We reviewed the charts from all acute stroke patients seen at Monmouth Medical Center from 2008-2012:
8% got t-PA.
75% were excluded because came outside the 3-4.5hr time frame for administration of t-PA.
9% were seen in time for t-PA, but either refused treatment or couldn’t get it because if a definite contra-indication.
8% did not get t-PA because of a “mild or rapidly improving deficit” – of those, 13% needed rehab placement, so there deficit wasn’t so mild after all!
Obviously, our goal is to give more t-PA to stroke patients who can benefit from the clot busting treatment.
We are working hard on public education events to get stroke patients to come to ED sooner, and we are also going to be treating more patients with “mild” deficits as long as they meet eligibility criteria.
What can you do?
Know the warning signs of stroke.
If you, or anyone you know, shows any of these signs call 911 and get them to the hospital right away.
Be a participant in your own or your loved one’s medical decision making – if there seems to be any residual stroke symptoms (however mild) ask about t-PA treatment for stroke.
This 46-year-old woman was healthy except for a history of occasional migraine headaches and cigarette smoking. On the day of admission she had fallen down a short flight of steps carrying a heavy box. About 2 hrs later she complained of some neck pain. Then later that evening developed abrupt onset left sided weakness. She arrived at the emergency room within 1.5 hrs of the onset of weakness. On examination, she was alert, but she had a right gaze deviation (she wouldn’t look to the left side) and the left side was completely paralyzed. She had a normal brain CT scan.
The stroke team was notified, and she was given intravenous thrombolytic (“clot busting”) drug therapy within 1/2 hr of her arrival at the hospital and 2 hrs since the onset of her symptoms.
Carotid ultrasound subsequently showed no flow in the right internal carotid artery, and carotid arteriography subsequently showed near occlusion of the artery from an arterial dissection (see image below, red arrow):
What is cervical artery dissection?
Cervical artery dissection is caused by bleeding inside the wall one of the major arteries in the neck.
This process is thought to be triggered by local injury to the inside layer of the vessel wall.
Cervical artery dissections occur from blunt trauma:
Cervical artery dissection can also occur after minor trauma, particularly in someone with a genetic predisposition:
What diseases predispose to arterial dissection?
There are some specific syndromes such as Marfan syndrome, Pseudoxanthoma elasticum and Ehlers- Danlos syndrome type IV that are associated with a weakness in the arterial wall making an arterial dissection more likely:
In other cases, the specific cause of arterial weakness is unknown, but there is ongoing research to try to identify genetic links.
What happens after a cervical artery dissection?
Symptoms can be caused from the damaged arterial wall itself (local symptoms) and some affected patients will later develop strokes.
Local symptoms include neck pain, unusual headache and/or Horner’s syndrome.
What about stroke?
Stroke symptoms only occur in 25-30% dissections and can occur several days after the neck trauma and/or onset of local symptoms.
The arterial dissection narrows the space inside the blood vessel (the lumen), so less blood flow gets to the brain:
Cervical arterial dissections can also cause stroke when pieces of blood clot break off and move with the blood flow only to block small arteries further inside the brain (cerebral thromboembolism), or if the dissection tracks across (and blocks off) an arterial branch (see below):
How is arterial dissection diagnosed?
Magnetic resonance imaging is probably the easiest way to make the diagnosis:
How is it treated?
In most cases the arterial dissection ultimately heals on its own without any surgical intervention. There has been some controversy surrounding the use of anticoagulant vs anti-platelet drugs for stroke prevention after cervical artery dissection, but most current data favors the use of the anti-platelet drug aspirin:
Of course, for patients presenting with symptoms of acute stroke, throbolytic therapy is also an option, and can improve outcome without increased risk in stroke from dissection:
Click here to find out more about cervical artery and dissection and stroke.
Click here to find out what to do if you think your having a stroke.
Click here to find out more the certified stroke center at Monmouth Medical Center.