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PROLONGED COMA MINIMALLY CONSCIOUS STATE by mikesanye

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                                                                                                                                2
 PROLONGED COMA MINIMALLY CONSCIOUS
                              STATE
                                                                            Dan Alexianu, Marius Prazaru
                                                                              Floreasca Emergency Hospital

                                                                                                              ABSTRACT
 With increasing refinements in the treatment of severe systemic diseases and cerebral injury, more and more patients who formerly
 would have died have survived for indefinite periods without regaining any meaningful mental function. These patients are wakeful and
 arousal but regain neither awareness nor purposeful behavior of any kind. If lasting, this syndrome is most appropriately called
 Persistent Vegetative State.
 We can not demonstrate with absolute assuredness the irreversibility of these cases. The clinic examination is the most important in
 estimation of this state. However, legally, socially and judicial it is considered irreversible the nontraumatic injuries/postanoxic
 ischemia, vascular injuries, toxic-metabolic injuries after three months; the traumatic injuries in patients under 45 years old must be
 evaluate after one year.
 The Persistent Vegetative State must be clearly distinguished from The Locked-in Syndrome or The De-afferented State in which
 there is little or no disturbance of awareness (consciousness) but the patient is not capable to respond adequately and from Akinetic
 Mutism – the patient is akinetic (motionless) and mute (doesn’t speak).
 Technological progresses in intensive care must be doubled by a compelling, continues and consumptive nursing, from the intensive
 care team and the family. The alternance between disciplinary methods and the privilege to treat such case with unexpected
 successes after months or years, are two elements that must be used with great diplomacy and experience.
 Key words: Vegetative state, Locked-in syndrome, Akinetic Mutism, neurological reanimation




   Consciousness: represents the summated activity                            above reflexes can be obtained, and the
of the cerebral cortex. It is characterized by                                plantar reflexes may be either flexor or
awareness and the ability to respond to                                       extensor (Babinski sign). Moreover, vigorous
environmental and intrinsic stimuli. Plum and                                 stimulation of the patient or distention of the
Posner differentiated between two aspects of                                  bladder may cause a stirring or moaning and
consciousness: arousal and content. The first is                              a quickening of respiration. These physical
linked to wakefulness and alertness, whereas the                              signs vary somewhat depending on the cause
second represents the sum of cognitive and affective                          of coma.
mental function. A variety of insults can cause                           For example, patients with alcoholic/toxic coma
impairment of one or both aspects of consciousness.                    may be areflexic and unresponsive to noxious
Among other causes these include structural brain                      stimuli, even when respiration and other vital
lesions, metabolic disturbances, hypoxia or                            functions are not threatened.
hypoperfusion and traumatic brain injury.                                 The repeated evaluation of the coma degree is
   The patient who appears to be asleep and is at                      most useful in assessing the direction in which the
the same time incapable of being aroused by external                   disease is evolving. Glasgow Coma Scale published
stimuli or inner need is in a state of coma.                           by Teasdale and Jennett in 1974, is probably the
   There are different degrees of coma:                                most familiar scale used in neurology, intensive care
   – deep coma: no reaction of any kind is                             and emergency medicine. The scale was created to
      obtainable: corneal, pupillary, pharyngeal,                      be a simple and reliable instrument in consciousness
      tendon, and plantar reflexes are in abeyance,                    level evaluation. It is easy to learn, understand and
      and tone in the limb muscles is diminished.                      apply.
   – moderate coma: pupillary reactions, reflex                           The way that Glasgow Coma Scale is evaluated
      ocular movements and corneal reflex are                          and the practitioner’s experience may give different
      preserved. Muscle tone in the limbs may be                       results with different prognostic effects.
      increased. Respiration may be slow or rapid,                        We must inventorize and compare daily, on the
      periodic, or deranged in other ways.                             medical history, the reactions to nursing and minor
   – superficial coma: sometimes referred to by                        surgical manoeuvres, and to aspiration manoeuvres
      the ambiguous term semicoma, most of the                         of airways secretions. These are very important


ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VII, NO. 2, 2008                                                                               57
58                                                  ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VII, NO. 2, 2008


elements in outcomes and prognosis of these                responsiveness is limited to primitive postural and
patients. The assessment of those cases must include       reflex movements of the limbs.
the transfer after 5-10 days into special neuro-               In brief, there is arousal or wakefulness and
rehabilitation clinics, with dedicated personnel,          alternating arousal-nonarousal cycles may be
independent and separately paid by the assurance           established, but the patient regains neither
systems. Theoretically in this clinics the patients        awareness nor purposeful behavior of any kind. This
are treated maximally 5 weeks. After that, they are        state is characterized by a number of EEG
transferred in chronic disease hospitals where they        abnormalities. After global anoxic injury, the EEG
get the same neurological rehabilitation treatment,        tends to display the most profound abnormalities,
this time using the family support trained “under          even to the point of being isoelectric.
way”. There are many studies that are proving a                If lasting, the above described syndrome is most
great neuroplasticity and axonal regeneration with         appropriately referred to as the persistent vegetative
reaferentation effect.                                     state (PVS) (Jennett and Plum). This term has gained
   Glasgow Outcome Scale was elaborated by                 wide acceptance and applies to the clinical situation
Jennett and Bond in 1975, in order to asses the long       whatever the underlying cause.
term prognosis in posttraumatic cerebral lesions.              The most common pathologic bases of this state
                                                           are diffuse cerebral injury due to head trauma,
                                                           widespread laminar necrosis of the cortex after
THE PERSISTENT VEGETATIVE STATE, LOCKED-
                                                           cardiac arrest, and thalamic necrosis from a number
    IN SYNDROME, AND AKINETIC MUTISM                       of causes. Occasionally, the most prominent
   With increasing refinements in the treatment of         changes are in the thalamic and subthalamic nuclei.
severe systemic diseases and cerebral injury, more         It is noteworthy that a persistent vegetative state
and more patients who formerly would have died             may also be the terminal phase of progressive
have survived for indefinite periods without               degenerative processes such as Alzheimer disease
regaining any meaningful mental function.                  and of Creutzfeldt-Jakob disease. The profound and
   Before the neuroreanimation age it was very             widespread dysfunction of the cerebrum is reflected
simple: the patients with severe cerebral lesions          by extreme reductions in cerebral blood flow and
used to die in more then 90% of cases; the rest used       metabolism, measured with positron emission
to recover with various degree of neurological             tomography (PET) and other techniques.
deficit.                                                       On the PET studies in a patient with carbon
   In present many efforts are made to precociously        monoxide poinsoning, Laureys and colleagues
remove all survival devices that are used in the           observed that the main difference between the PVS
intensive care unit: ventilatory weaning, gastric and      and the recovered state was the presence of
urinary tube removal.                                      hypometabolism in the parietal lobe association
                                                           areas in the former. However, it is quite clear that
   For the first week or two after the cerebral injury,
                                                           the neuroanatomic basis of the vegetative state is
these patients are in a state of deep coma. Then
                                                           far more complex.
they begin to open their eyes, at first in response to
                                                               Additional terms that have been used to describe
painful stimuli and later spontaneously and for
                                                           this syndrome of preserved autonomic and res-
increasingly prolonged periods. The patient may
                                                           piratory function without cognition include: apallic
blink in response to threat or to light and intermit-
                                                           syndrome and neocortical death.
tently the eyes move from side to side, seemingly
                                                               Recently, a commission has codified the features
following objects or fixating momentarily on the
                                                           of PVS and suggested dropping a number of related
physician or a family member and giving the
                                                           ambiguous terms although some, such as akinetic
erroneous impression of recognition. Respiration
                                                           mutism have a more specific neurologic meaning
may quicken in response to stimulation and certain
                                                           and still find use.
automatisms may be observed:                                   It is difficult to predict which patients will fall
   – swallowing                                            permanently into the PVS category. We can not
   – moaning                                               demonstrate with absolute assuredness the
   – grunting                                              irreversibility; the clinic examination is the most
   – grimacing                                             important in estimation of this state. However,
   However, the patient remains totally inattentive,       legally, socially and judicial it is considered
doesn’t speak, and shows no signs of awareness,            irreversible the nontraumatic injuries\ postanoxic
spontaneously or to environmental stimuli;                 ischemia, vascular injuries, toxic-metabolic injuries
ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VII, NO. 2, 2008                                                       59


after three months; the traumatic injuries in patients    and the family. The alternance between disciplinary
under 45 years old must be evaluated after one year.      methods and the privilege to treat such case with
   Plum and Posner have reported that of 45               unexpected successes after month or years, are two
patients with signs of the vegetative state at 1 week,    elements that must be used with great diplomacy
13 awakened and 5 had satisfactory outcomes; after        and experience.
being vegetative for close to 2 weeks, only one               The intensity of intensive care manoeuvres must
recovered to a level of moderate disability. After        be adapted to each and every case:
two weeks the prognosis was inconclusive. Larger              1. in intensive care units for the 5-10 days
studies by Higashi and colleagues have given                  2. in specialized neurorehabilitation units, after
similar results.                                                 the intensive care period, for maximum 5
   As a guide to prognosis in head injury, Braakman              weeks
and colleagues found that among a large group of              3. in clinics or hospitals for chronics specialized
comatose patients, 59 percent regained conscious-                in that kind of pathology.
ness within 6 hours; of those in a vegetative state at        The neurorehabilitation teams, independent and
3 months, none became independent. At no time             coordinated with other specialists from intensive
after the onset of coma was it possible to distinguish    care unit, will adapt the manoeuvres to patients
patients who would remain in a vegetative state from      tolerance. Those are patients with hemodynamic
those who would die. In some cases the diagnosis          instability, treated with complex therapy sometimes
of vegetative state can be applied soon after the         excessively sophisticated: extrarenal purification,
onset of coma, rather than requiring coma to persist      hypothermia, high-tech artificial ventilation modes,
for several months, but fewer cases would be              cardiac drugs.
“persistent”. For this reason and because of the              For the first 5-10 days from the accident, neuro-
anxiety created for families by such a final              rehabilitators will create a positive, encouraging
diagnosis, it has been suggested that the term be         psychoemotional contact with the patient and his
abandoned.                                                family.
   It is useful to maintain a critical view of news           The rehabilitation scores are depending
reports of remarkable recuperation from prolonged         sometimes of the position of the patient during
coma or the vegetative state. When the details of         examination: for example in sitting position the
such cases become known, it is evident that               patient awakens frequently; this is not always
recovery might reasonably have been expected.             happening in the other positions. The repeated
   There are, however, numerous reported                  stimulation at short intervals may create the
instances of partial recovery in patients, particularly   fatigability phenomenon with inexact conclusions
children, who display vegetative features for several     about the condition and evolution of the patient.
weeks or even several months after injury.                    Reestablishment and stimulation by any means
   Such observations cast doubt on unqualified            of visual, tactile, auditory, musculoskeletal,
claims of success with various therapies such as          vibrating receptors and continuous verbal
sensory stimulation. Nevertheless, the occurrence         communication, has a primordial role rehabilitation
of rare instances of very late recovery in adults must    of these cases.
be acknowledged.
   The decision “do not resuscitate” must be                            LOCKED-IN SYNDROME
inventoried through the level of medical knowledge
of those who are taking on the risk to make this              The states of coma and the PVS, described above,
call. Actual technologies such as “functional ” MR        must be clearly distinguished from a clinical state
are trying to evaluate the chances of recovery from       in which there is little or no disturbance of
Vegetative State or Minimally Conscious State. For        awareness (consciousness) but the patient is not
example: telling a pleasant story to the patient opens    capable to respond adequately. This state is called
certain neuronal circuits, inversely, an unpleasant       the locked-in syndrome or the de-afferented state.
story does not open those circuits.                       The term pseudocoma as a synonym for this state
                                                          is best avoided, since it is used by some physicians
              NEUROREHABILITATION                         to connote the feigned unconsciousness of the
                                                          hysteric or malingerer. The de-afferented syndrome
   Technological progresses in intensive care must        is due most often to a lesion of the ventral pons
be doubled by a compelling, continues and                 (basis pontis), in some cases as a result of basilar
consumptive nursing, from the intensive care team         artery occlusion. Such an infarction may spare both
60                                                 ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VII, NO. 2, 2008


the somatosensory pathways and the ascending                 The psychiatric patient with catatonia appears
neuronal systems that are responsible for arousal         unresponsive, simulating stupor, light coma, or the
and wakefulness as well as certain midbrain               akinetic mute state. There are no signs of structural
elements that allow the eyelids to be raised and give     brain disease such as pupillary or reflex ab-
the appearance of wakefulness.                            normalities. Oculocephalic responses are preserved
   The lesion interrupts the corticobulbar and            as in the awake state; the eyes move concurrently
corticospinal pathways, depriving the patient of          as the head is turned. There is usually resistance to
speech and the capacity to respond in any way             eye opening, and some patients display a waxy
except by vertical gaze and blinking.                     flexibility of passive limb movement that gives the
   Severe motor neuropathy (Guillain-Barré syn-           examiner a feeling of bending a wax rod (flexibilitas
drome), pontine myelinolysis, tumors, encephalitis,       cerea). There is also the retention for a long period
pontine infarction or recurrent paralysis may have        of seemingly uncomfortable limb postures
a similar effect. Such patients appear comatose but       (catalepsy).
are awake and alert although mute and quadriplegic.          In conclusion, from personal experience and
Decerebrate posturing or flexor spasms may be             from literature dates, in present it is impossible to
seen. The patient opens the eyes voluntary, and           determine with precision the prognosis in every
vertical eye movements may be seen. The EEG is            case; the emotional, financial and social effort is
normal.                                                   disproportionately big comparing to final results.
   This state was called by Cairms and colleagues         However the prognosis must be adapted and
akinetic mutism: the patient is akinetic (motionless)     realized according to some medical, social and
and mute (doesn’t speak). They described a patient        family rules.
who appeared to be awake but was unresponsive.               This situation determines the necessity to adapt
Following each of several evacuations of a third          the assistance systems so that after 7-14 days of
ventricular cyst, the patient would become aware
                                                          intensive care the patient is transferred to neuro
and responsive but would have no memory for any
                                                          rehabilitation supraspecialized for vegetative state
of the events that had taken place when she was in
                                                          clinics and after 4-5 weeks of rehabilitation the
the akinetic-mute state. This rare state of apparent
                                                          patients are transferred into asylum-hospitals or at
vigilance in an imperceptive and unresponsive
                                                          home were treatment conditions are assured.
patient has been referred to by French authors as
                                                             It must be mentioned that in those cases 30-80%
“coma vigile”.
   The term akinetic mutism has been applied to           recover with variable and unforeseeable
yet another group of patients who are silent and          neuropsychiatric deficit. The reevaluation must be
inert as a result of bilateral lesions of the anterior    obtained at 6 months and at the end at 2 years from
parts of the frontal lobes, leaving intact the motor      the beginning; albeit there are cases of late recovery
and sensory pathways; the patient is profoundly           after 6 years or more.
apathetic and abulic and unlike Cairns’s patient,            In Romania there are approximately 12000 cases
registers most of what is happening about him and         every year, most of them treated in intensive care
forms memories. Patients with this syndrome are           units, for more then 14 days. They are blocking
immobile and will usually lie wit there eyes closed.      hospital beds with high prices and results
Sleep-wake cycles exist.                                  disproportionately low.
   Outcome is variable and related to the underlying
cause and the extend of the brainstem lesions.
Mortality usually from pneumonia is approximately
70% when the cause is a vascular disturbance and          BIBLIOGRAPHY:
about 40% in nonvascular cases. Survivors may             1.   Arseni C., Alexianu D. – Phases in prolonged coma treatment.
recover partially or completely over a period of               Surgery Buc. Vol. 24, No. 6, 1972, p558-564
weeks to months. Consider reevaluation to 6 months        2.   Alexianu D. – Vegetative State VM. No. 5742, 2005
                                                          3.   Plum F., J.B. Posner – Diagnosis of Stupor and Coma. Ed Oxford
and to 2 years.                                                Press 2007

								
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