Specific information regarding the Communication Sciences and Disorders' Acute Care Speech Language Pathology practicum led by Carley Evans MS CCC SLP. Carley is a medical speech pathologist at the Evelyn Trammell Institute for Voice and Swallowing of the Medical University of South Carolina in Charleston. If you are new to this practicum, start with the oldest post listed in Archive.

Friday, September 14, 2007

Coma Stimulation

What do you know about coma stimulation?

What kind of stimulation?
Is it effective?
Who does it?
What is the rationale?
For how long?

What is a persistent vegetative state?

7 comments:

christie said...

Persistant Vegetative State:
They are unresponsive to external stimuli, except, possibly, pain stimuli. Unlike coma, in which the patient's eyes are closed, PVS patients often open their eyes. Their eyes might be in a relatively fixed position, or track moving objects, or move in an unsynchronized manner. They may experience sleep-wake cycles, or be in a state of chronic wakefulness. They may exhibit some behaviors that can be construed as arising from partial consciousness, such as grinding their teeth, swallowing, smiling, shedding tears, grunting, moaning, or screaming without any apparent external stimulus. Those in a vegetative state usually emerge from this state within 30 days. Those who remain in this state for more than 30 days are considered to be in a persistant vegetative state. The younger the patient is, the more likely they are to emerge from a vegetative state.

christie said...

Coma Stimulation:Functional electrical stimulation (commonly abbreviated as FES) is a technique that uses electrical currents to activate nerves innervating extremities affected by paralysis resulting from spinal cord injury (SCI), head injury, stroke or other neurological disorders, restoring function in people with disabilities.

Injuries to the spinal cord interfere with electrical signals between the brain and the muscles, resulting in paralysis below the level of injury. Restoration of limb function as well as regulation of organ function are the main application of FES, although FES is also used for treatment of pain, pressure, sore prevention, etc.

Some examples of FES applications involve the use of Neuroprostheses that allow people with paraplegia to stand, restore hand grasp function in people with quadriplegia, or restore bowel and bladder function.

Electrical stimulation for the purpose of helping persons with paralysis of the arms or legs mainly focuses on the neuromuscular transmission peripherally. E-stim can also be used for central nervous system stimulation to hasten awakening from coma or the vegetative state. There is a long history of neurosurgeons who have implanted electrodes into the brain and spinal cord, especially in Japan, for increasing cerebral blood flow and certain neurotransmitters in persons in long term coma states.

Beginning in 1991 in Greenville, North Carolina (East Carolina University) and shortly after that in Charlottesville,Virginia (University of Virginia), the right median nerve has been used as a portal to help awaken injured human brains. Trains of differentiated square electrical pulses at 40 Hz (a frequency for upregulation of the thalamus), 20 seconds on and 40 seconds off, have been applied to the palmar side of the right wrist for transdermal stimulation of the right median nerve at low amplitudes, enough to produce contraction of the thumb. Battery powered FDA approved electrical neuromuscular stimulators have been used in these research projects connected by wires to the pair of right wrist electrodes embedded in a custom made plastic orthosis to localize the stimulation target. The right median nerve was selected as the electrical portal as there is large cortical respresentation of that nerve in the dominant left cerebral hemipshere. By subcortical connections, the transmitted signals go to Broca's motor/speech planning area (whether the person is right or left handed, the majority are left hemisphere dominant). Awakening from deep coma from motor vehicle crashes with closed head injury in the Glasgow Coma Scale range of 4-6 can be expected to respond in half of the treated cases after two to four weeks of 8 hours/day electrical treatment,if started within one to two weeks of the severe brain trauma. The advantage of the shorter than expected period of unconsciousness is a quicker start into a neurorehabilitation program to encourage ambulation and talking.

So FES appears to be transdermal stimulation. As far as its effectiveness goes...I searched through some articles and found a cochrane review of this type of stimulation for coma awakening. There were only a few articles that even met the inclusion criteria for the review. The results are as follows:
Results: Three studies (one RCT and two CCTs) with 68 traumatic brain-injured patients in total, most of whom were road accident victims, met the inclusion criteria. The overall methodological quality was poor and studies differed widely in terms of study design and conduct. Moreover, due to the diversity in reporting of outcome measures, a quantitative metanalysis was not possible. None of the three studies provided useful and valid results on outcomes of clinical relevance for coma patients.

My conclusion is a call for more research. There is a lot of research on FES for spinal cord injuries, but not alot on coma stimulation.

DBS (deep brain stimulation) has also been used to hasten coma awakening. I found the following article on it:
Abstract
Characterization and Modification of Brain Activity with Deep Brain Stimulation in Patients in a Persistent Vegetative State: Pain-Related Late Positive Component of Cerebral Evoked Potential
YOICHI KATAYAMA11Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan, TAKASHI TSUBOKAWA11Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan, TAKAMITSU YAMAMOTO11Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan, TERUYASU HIRAYAMA11Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan, SHUHEI MIYAZAKI11Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan, and SEIGOU KOYAMA11Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan
A series of eight patients in a persistent vegetative state (PVS) were subjected to chronic deep brain stimulation (DBS) for the purpose of promoting recovery from the PVS. The characteristics of the brain activity in these patients were evaluated from the late positive component of the cerebral evoked potential in response to painful stimuli (pain-related P250). While any neurological scoring system for the comatose state includes evaluations of motor reactions to painful stimuli, the pain-related P250 is unique in terms of its ability to assess the cortical responsiveness to painful stimuli directly and quantitatively without involving functions of the motor system. It was found that the pain-related P250 was more or less depressed in patients in a PVS. It was repeatedly demonstrated in four patients, however, that the pain-related P250 could be transiently increased by preceding stimulation of the mesencephalic reticular formation. Furthermore, a persistent increase in the pain-related P250 was produced in these four patients following chronic DBS of the mesencephalic reticular formation or nonspecific thalamic nuclei for more than 6 months, and this was correlated with the clinical improvements. These results imply that responsiveness at the cortical level to pain is depressed in the PVS. It also appears that some fraction of the depression may, however, be functionally produced and potentially reversible.

christie said...

Also, I read the article on patient interview and enjoyed it. Here are some snippets of what I found most interesting/helpful:

-A poorly conducted historical data collecting session can misdirect the entire assessment process before it begins.

-Allowing for open-ended conversation and using fewer leading and canned querstions were associated with more accurate diagnosis

-A completely open-ended question that allows the patient great latitude in his/her response (such as, "what brings you here"?) is most appropriate

-Ask the patient why they think they are having problems swallowing

-Coughing or choking on swallowing exclusively with thin liquids is a strong indicator of laryngeal penetration of swallowed materials. By itself, this complaint may indicate a poor coordination of airway protection and bolus propulsion often associated with pharyngeal delay. When combined with complains of excessive saliva or mucus, one can infer that there is a weakness in the propulsion of secretions during spontaneous nonbolus swallows.

-The frequency should be characterized with respect to the number of times the symptom occurs during the meal

-Odynophagia (pain on swallowing) should be characterized as burning, sharp, dull, aching, gnawing, or throbbing. The patient should provide an exact location by pointing to the area that hurts. An exact description of the onset of the pain also should be obtained.

-sudden onset of odynophagia could indicate the presence of infection or recurrence of cancer. Patients who recently have been trached or orall intubated often complain of pain on swallowing.

-Globus: lump in throat linked to hypertrophy of lingual tonsils, sinusitis, spondylitis with cervical osteophytes, and gastroesophageal reflux.

Table 1-21 on page 27 was very helpful as well.

Carley said...

Did you "google" coma stimulation? Try "googling" : Rancho Los Amigos Scale, Glasgow Coma Scale, Neuro Skills... then search those websites for information on "coma stim" or "coma stimulation techniques," etc.

But, don't spend too much time on this...

Like the information you found on "vegetative states."

Unknown said...

Hello, Mrs Beatrice from Texas and i have a 24-year old son who was suffering from Persistent Vegetative State

(PVS) -Brain and Spinal Cord.i am filled with joy in my heart sharing this testimony,my son had an accident which

led to severe brain damage,he was then rushed to a nearby hospital by with immediate treatment, two months later

the doctor called me and told me that my son is in the state of consciousness an unresponsive wakefulness

syndrome,that he will not be able to recognize anyone of us,that there is nothing he can do for us,since then is

been 4 years until one faithful day i went online and i saw a testimony of how a herbal doctor DR RAHANY helped

someone with the same condition,immediately i contacted him rahanyherbalcenter@yahoo.com,i told him what brought me

to him,he told me not to worry anymore that my son is going to remember everything he has lost.He sent me some

herbs which he told me will make him recover, to my surprise one month of my son taking the herbs,immediately he
recovered back his memory,and he is able to converse with everyone.i want to use this medium to let the world know

that there is solution,don't give up hopes cause my son is now fully well.you can contact him:

(rahanyherbalcenter@yahoo.com).HE also cure 1.AUTISM 2.HIV/AIDS 3.PREGNANCY.E.T.C

Unknown said...

Hello, Mrs Beatrice from Texas and i have a 24-year old son who was suffering from Persistent Vegetative State (PVS) -Brain and Spinal Cord.i am filled with joy in my heart sharing this testimony,my son had an accident which led to severe brain damage,he was then rushed to a nearby hospital by with immediate treatment, two months later the doctor called me and told me that my son is in the state of consciousness an unresponsive wakefulness syndrome,that he will not be able to recognize anyone of us,that there is nothing he can do for us,since then is been 4 years until one faithful day i went online and i saw a testimony of how a herbal doctor DR RAHANY helped someone with the same condition,immediately i contacted him rahanyherbalcenter@yahoo.com,i told him what brought me to him,he told me not to worry anymore that my son is going to remember everything he has lost.He sent me some herbs which he told me will make him recover, to my surprise one month of my son taking the herbs,immediately he
recovered back his memory,and he is able to converse with everyone.i want to use this medium to let the world know that there is solution,don't give up hopes cause my son is now fully well.you can contact him:(rahanyherbalcenter@yahoo.com).HE also cure 1.AUTISM 2.HIV/AIDS 3.PREGNANCY.E.T.C

Paul Fogle, Ph.D., CCC-SLP said...

Hello SLPs,

I am an SLP and have been for 49 years. I was a university professor for 35 years and taught all of the neuropathology courses plus counseling skills for speech-language pathologists and many others. I worked many summers in acute, subacute and convalescent hospitals and have maintained a private practice. I am the co-author of the RIPA-G, The Source for Cognitive Retraining for Independent Livings, Classic Aphasia Stimuli Kit (CATS), and 5 textbooks, including two editions of "Counseling Skills for Speech-Language Pathologists and Audiologists." I am currently writing a new textbook for Jones-Bartlett Learning titled "Traumatic Brain Injury in Infants, Children, and Adolescents." I have a section on coma and would like to include information about coma stimulation but have not found any literature discussing SLP's work in this area. Does anyone know of any published literature that can support our work in this important area of trauma care? Please email me at paulfoglephd@gmail.com. My website is www.PaulFoglePhD.com.

Thank you for your consideration.

Best regards,
Paul