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.