Acute confusion (Delirium)
Introduction
Confusion has
been defined as a state of altered consciousness in which patients are
bewildered and misinterpret the world around them.
Primary and
secondary confusion
Primary confusion
is caused by a direct pathology in the central nervous system, eg. CNS
injury, dementia
Dementia is a
chronic brain syndrome
Leads to
chronic confusion
Causes -
Alzheimer's disease, Pick`s disease, Creutzfeldt-Jakob Disease, HIV dementia.
Typically the
onset of primary conditions is insidious
Acute,
secondary confusion may complicate primary
Secondary
confusion is caused by something else
Clinical
features
Alterations
cognition, general behaviour, motor activity and features of psychotic or neurotic
conditions
Thinking
becomes disorganised
Memory
disturbance.
Alteration in
the sleep - wake cycle
Distress
Severity of
confusion may fluctuate during the course of the day
Confusion for
time, place, person
Use a mental
test score tool
Diagnostic criteria
from the American Psychiatric Association for delirium
1. Disturbance
of consciousness (ie. reduced clarity of awareness of the environment) with
reduced ability to focus, sustain or shift attention.
2. A change in
cognition (such as memory defect, disorientation, language disturbance) or the
development of a perceptual disturbance that is not better accounted for by a
pre-existing or evolving dementia.
3. The
disturbance develops over a short period of time (usually hours to days) and
tends to fluctuate during the course of the day.
4. There is
evidence from the history, physical examination, or laboratory findings that
the disturbance is caused by the direct physiological consequences of a general
medical condition, substance intoxication or substance withdrawal.
Aetiology
A more
descriptive term for acute brain syndrome is diffuse encephalopathy.
Age is a risk
factor as older people have less redundancy, (spare capacity) in terms of
cortical neurones and cerebral perfusion.
Causes of secondary confusion
Migraine in children Cerebrovascular
insufficiency
Cerebrovascular disease Respiratory
disease
Anaemia Space
occupying lesions
Toxic problems Malnutrition
Dehydration Electrolyte
disturbance
Systemic infections Hypothermia
Hyperthermia Post
operative
Depression Psychosis
Concussion Constipation
Terminal illness Heart
failure
Environmental
Confusion
Introduction
Confusion has
been defined as `a state of altered consciousness in which patients are
bewildered and misinterpret the world around them`(Kumar and Clark, 1994). This
should not be confused with stupor which is an abnormal sleepy state.
Traditionally, delirium has been described as a state of high arousal with
acute confusion and agitation often accompanied by hallucinations. However, the
current trend is to classify any acute confusional state as delirium, (American
Psychiatric Association 1994).
Clinical
features
In confusion
there may be alterations in orientation, cognition, general behaviour, motor
activity and features of psychotic or neurotic conditions, (Hadley Vermeersch
and Henly 1997). Thinking becomes disorganised and there is usually memory
disturbance. Alteration in the sleep - wake cycle is common, (Bennett and
Plumb, 1995). Distress is another possible manifestation, (Barraclough, 1997).
The severity of confusion may fluctuate during the course of the day. In mild
confusion there may be disorientation for time, this means the patient does not
know where they are in time. This may be for the hour, day, month or year. As
the condition becomes more severe place is also confused so the individual does
not know where they are, often believing they are somewhere else. In still more
severe states there is disorientation for person, for example nurses may be
believed to be members of the patients family. Table 1 gives the diagnostic
criteria from the American Psychiatric Association for delirium, (ie. acute
confusion). A more descriptive term for acute brain syndrome is diffuse
encephalopathy, which describes the behavioural state produced by a group of
brain effecting disorders, (Bennett and Plum, 1995).
Age is a risk
factor as older people have less redundancy, (spare capacity) in terms of
cortical neurones and cerebral perfusion. Those with memory impairment, sight
or hearing problems are at increased risk, (Barraclough, 1997).
Causes of
confusion
Confusion is a
potentially serious feature. Flaherty, (1998) points out that acute confusion is
associated with significant morbidity and mortality among older persons. This
means that confusion should be explained as it may be a symptom of a
potentially serious underlying condition. It is sometimes useful to
differentiate between primary and secondary causes of confusion.
Primary
Primary
confusion is caused by a direct pathology in the central nervous system. This
could be caused by CNS injury or occur as part of a dementia resulting in
chronic confusion. Primary causes of confusion may therefore include,
Alzheimer's disease, Pick`s disease, Creutzfeldt-Jakob Disease and HIV
dementia. Dementia is a chronic brain syndrome characterised by a progressive
irreversible impairment of intellectual function often caused by loss of
cortical neurones. Typically the onset in these conditions is insidious, and
there are no effective curative treatments.
Individuals
with dementia may become acutely more confused if they acquire another
condition also causing confusion as a secondary effect. This is referred to as
an acute on chronic confusion.
So called
sundown syndrome has been identified in 24% of patients with Alzheimer's
disease. This is characterised by restlessness and other multiple behavioural
disturbances in the evening and may be related to use of sedatives,
particularly chloral hydrate and length of time spent in hospital, (Little et
al, 1995).
Secondary
In secondary
confusion, the function of the brain is embarrassed secondary to an underlying
medical condition. It is important that any underlying contributory condition
is identified as this is often reversible. When the underlying condition is
corrected the confusion will usually be reversed. The onset of secondary
confusion is often relatively acute occurring over hours or days. Acute confusion
is a common complication of hospitalisation in the elderly that impacts on both
the use of health care resources and the functional status of individuals,
(Kozak-Campbell and Hughes 1996).
Although
confusion is usually associated with the elderly this is not always the case.
For example migraine in children can present as a state of confusion or
agitation with or without a history of headaches. These features can arise
spontaneously or can be triggered by mild head trauma. Transient blindness and
hemiplegia may accompany the confusional state, (Ferrera and Reicho 1996). A
typical duration of confusion associated with migraine in children has been
found to be 2-24 hours, (Shaabat 1996). The cause of confusion in migraine is
probably localised cerebral hypoperfusion, (Nezu, 1997)
In addition to
the primary causes of dementia discussed above, irreversible impairment of
brain function may occur secondary to cerebrovascular insufficiency which will
lead to neuronal hypoxia. As well as hypoxia, an inadequate perfusion of the
brain will deprive nerve cells of essential nutrients and waste products of
metabolism may not be removed efficiently. Over time these factors can cause
neuronal death and consequent irreversible damage to the brain leading to
dementia. This condition may be due to ischaemic changes secondary to
atherosclerosis or occur as a result of multiple cerebral infarcts. Emboli,
often blood clots, may arise from thrombosis in the heart or in atheromatus
arteries anywhere between the heart and the brain. Acute confusion may also be
seen following a cerebrovascular accident. Other possible causes of prolonged
cerebral hypoxia include pulmonary disease which may result in hypoxaemia,
anaemia which reduces the oxygen carrying capacity of the blood, hypotension
which reduces cerebral perfusion and heart disease which may also lead to
impaired cerebral circulation.
Another
possible cause of organic brain pathology leading to confusion are space
occupying lesions. These may occur as a result of primary or secondary
neoplasms, haematoma or as a result of infections such as tuberculosis. These
conditions may be complicated by raised intracranial pressure.
Older patients
are more likely to suffer from confusion in response to prescribed and non -
prescribed drugs than younger people, (McMinn, 1995). Over use of medications
has been identified as the most common cause of delirium by Jorden and
Torrance, (1995). Polypharmacy should be avoided in the elderly as the risk of
adverse drug events rises exponentially with the number of medications
prescribed, (Flaherty, 1998). Confusion may also be a feature of drug
withdrawal, particularly when patients have used alcohol, opiates or
benzodiazepines, (Barraclough, 1997). A variety of non - prescribed drugs may
lead to confusion, for example alcohol, hallucinogens, opiates and
amphetamines, (Bennett and Plumb 1995). Malnutrition and dehydration may also
complicate non - prescribed drug use. Toxicity from non - pharmacological
causes can also result in confusion, this may be caused by uraemia or
electrolyte imbalance secondary to renal or hepatic disfunction. Metabolic or
endocrine disorders are further possible causes.
Nutritional
deficiencies are may causes of confusion in the elderly. Hypoglycaemia may lead
to reduced cerebral function as glucose is essential for neuronal metabolism.
Lack of the B vitamins is a well known cause of confusion. Vitamin B acts as a
cofactor, or co enzyme, these factors are non - proteins which combine with
protein based components to form a complete functional enzyme, (Anderson,
1994). Nutrients may be supplemented, but the use of supplements should always
be accompanied by the restitution of a normal adequate balanced diet.
Dehydration is another frequent cause of confusion in the elderly, (Mentes
and Buckwalter, 1997). Dehydration
may be caused by diarrhoea and vomiting, environmental heat, reduced fluid
intake, fever or use of diuretics. Ideally these deficiencies should be
prevented, however if they present the confusion should be rapidly reversed
with appropriate management. Electrolyte disturbance may independently cause
confusion or may complicate dehydration.
Infections and
fevers are an additional possible cause of confusion. This may result from
almost any systemic infection however respiratory and urinary infections are
frequent causes. Confusion may be caused by the presence of bacterial toxins in
the blood or by dehydration caused by the increase in insensible loss of fluid
as a result of fever. Hypothermia is another cause which may be encountered in
the community. Abnormally high or low temperature can adversely effect the
enzymic systems in the neurones which facilitate intracellular energy
production.
Post operative
confusion in the elderly is frequently seen, this has been related to reduced
cerebral perfusion as a contributory factor, (Kessler et al, 1997). Post
operative confusion has been associated with prolonged hospital stays and
increased postoperative mortality, (Ballard-Ferguson, 1997).
Brooking,
(1992) includes environment a cause of confusion. Sensory deprivation may be a
factor especially when older people are removed from their familiar home
environment. Other contributory factors may include noise in a hospital ward,
unfamiliar people, lack of clocks or calendars and lights being kept on
overnight.
Confusion may
arise as a result of major depression or psychoses, (Espino et al 1998). In
addition acute and transient functional psychosis may sometimes mimic acute
confusional states (Murai, Toichi and
Sengoku, 1996). Other possible causes include Parkinson's disease, constipation
and Huntington`s disease. Often in older patients several factors may
contribute towards confusion in an individual. Interestingly the common causes
of confusion may vary with geographical location, for example in Ethiopia the
most common cause was found to be infections, (Melka, Tekie-Haimanot and
Assefa, 1997).
Confusion may
occur in terminal care and may be part of terminal agitation. Here the
underlying cause will vary with the cause of the patients terminal condition
but may include ureamia, dehydration and cerebral hypoxia or metastasis.
Nursing
measures
Espino et al
(1998) has claimed all but the rarest causes of confusion can usually be
identified based on the complete history, medication review, physical
examination, mental status evaluation and laboratory evaluation with
longitudinal revaluation. Given the multiple possible causes of confusion
accurate nursing assessment is vital, (MIller et al, 1996), Confusion has been
considered to be a symptom of a failure in brain function with many possible
causes, (Feske, 1998). As many of these conditions may progress and lead to
further morbidity or death the cause of the confusion should be identified.
Thurston, (1997) warns that nurses should not to succumb to the temptation of
assuming that confusion is merely part of a progressive dementia in an elderly
person and therefore incapable of treatment, as a cause may be found with
appropriate investigations.
Use of a
specific cognitive screening tool may aid in assessment and monitoring the
evolution of a confusional state, (Jitapunkul, Pillay and Ebrahim, 1991), (table 2). However it is important to
remember such assessments will not differentiate between chronic confusion resulting
from dementia and the delirium of acute confusion.
Basic nursing
observations may yield useful information for example pyrexia or hypothermia
may be identified, irregularities in the pulse may indicate a cardiac
component, abnormal or reduced respirations may lead to hypoxia and observation
of blood pressure may indicate hypo or hypertension.
Kozak-Campbell
and Hughes, (1996) identify three aspects of nursing care necessary to provide
optimum nursing care in confused patients, Firstly the nurse's ability to
differentiate acute confusion from other common conditions in the hospitalised
elderly, chiefly dementia or depression. Secondly the nurse's ability to
identify factors contributing to confusion and thirdly the implementation of
interventions to minimise the effects of these factors on the patient.
Very often
confused patient may not be able to tell nurses if they are in pain or
suffering something. This means that in addition to trying to improve
communication nurses need to assess what other problems an individual has which
they may be unable to communicate. Acute confusion is a significant problem
among elderly surgical patients, and it can impair the older persons ability to
localise, interpret, or communicate discomfort to care-givers. Discomfort is a
common experience for hospitalised older patients, especially those recovering
from trauma or surgery. Self-report is not a reliable indicator of discomfort
in elderly confused patients. Miller, Moore and Schofield, (1996) recommend that health
care providers focus on discomfort as they provide care to these patients, and
intervene in a preventive fashion.
It has been
suggested that primary nursing is a useful approach when nursing a confused
patient, (Saunders, 1995). This will allow opportunity for the person to get to
know a few individual nurses who have a consistent approach with which the
person may become familiar. Patients should be nursed in a well lit room single
room and should not be moved around the ward or from ward to ward.
Clear
communication is essential to reduce confusion. A relaxed non - threatening
approach may help to put an individual at ease. Nurses should communicate at
the same level as the patient and touch may be used where appropriate. Patients
should be given information to improve orientation whenever possible, probably
with every intervention, (Jones 1995). This may be achieved by reminding
patients where they are whenever necessary, clocks and calendars should be
clearly visible. Orientation may be improved by frequent visits from friends
and family. Even in severely demented patients, people known for many years are
usually recognised and help to put the individual at ease. In addition the
introduction of familiar objects and other changes which make a hospital
environment more homelike can be beneficial, (Forreman and Zane, 1996).
Confused
patients are at increased risk of injury, nurses need to think about the
environment to reduce the risk of any untoward incidents such as falls or burns
with hot drinks. They are also more likely to climb out of bed and pull out
catheters, nasogastric tubes and intravenous lines, (Sanders, 1995). Wandering
behaviour may also occur, this may be due to disorientation for place but may
also have a cause such as looking for the toilet or food. Other complications
confused patients are at increased risk of include pressure sores, nosocomial
infections and continence problems.
It has been
demonstrated that simple nursing strategies such as using a toileting regimen
for patients who were both confused and had mobility problems could
significantly reduce falls, (Bakarich, McMillan and Prosser, 1997). These workers
demonstrated a 53% reduction in falls, (n = 2, 023) when a regular toileting
protocol was introduced. Ensuring adequate nutrition and hydration are basic
but essential nursing functions. Excessive activity leading to fatigue may
contribute to confusion so nurses should ensure adequate rest periods.
Constructive activity should also be employed to increase the interest an individual
takes in his or her environment.
There is a
potential danger to nurses from confused patients especially when care on the
person is being performed. Patients may mis - interpret a nurses action so it
should be ensured the patients is fully informed of all interventions and their
co-operation gained as much as possible. Sedation may be required in extreme
circumstances to manage acute confusion and if so haloperidol is most
appropriate. Foreman and Zane, (1996) claim that with proper management acute
confusion should resolve in three to four days.
Delirium
Delirium is characterised by a
disturbance of consciousness and a change in cognition that develop over a
short period of time. The disorder has a tendency to fluctuate during the course
of the day, and there is evidence from the history, examination or
investigations that the delirium is direct consequence of a general medical
condition, drug withdrawal or intoxication.
Features
1. Disturbance of consciousness (ie.
reduced clarity of awareness of the environment) with reduced ability to focus,
sustain or shift attention.
2. A change in cognition (such as
memory defect, disorientation, language disturbance) or the development of a
perceptual disturbance that is not better accounted for by a pre-existing or
evolving dementia.
3. The disturbance develops over a
short period of time (usually hours to days) and tends to fluctuate during the
course of the day.
4. There is evidence from the history,
physical examination, or laboratory findings that the disturbance is caused by
the direct physiological consequences of a general medical condition, substance
intoxication or substance withdrawal.
Table 1. After
the American Psychiatric Association 1994, (DSM IV)
The patient is asked the following
questions
1. Age
2. Time (to the nearest hour)
3. Address for recall at end of test,
(eg. 7 Bridge St.)
4. Year
5. Name of hospital patient is in
6. Recognition of 2 persons, (eg.
doctor, nurse)
7. Date of birth
8. Year of 1st World War
9. Name of present monarch
10. Count backwards from 20 to 1
Table 2.
Abbreviated Mental Test Score, (AMT). A score of less than 8 out of 10 is
abnormal, (Jitapunkul, Pillay and Ebrahim, 1991)
References
American
Psychiatric Association, (1994), Diagnostic
and Statistical Manual of Mental Disorders, (4th Ed.) Washington DC., American
Psychiatric Association.
Anderson KN.
Anderson LE. Glanze WD. (1994), Mosby`s Dictionary, (4th. Ed), Moseby,
St. Louis.
Bakarich
A. McMillan V. Prosser R. (1997), The effect of a
nursing intervention on the incidence of older patient falls, Australian Journal of Advanced
Nursing, 15(1):26-31.
Barraclough J
(1997), Depression, anxiety and confusion, BMJ, vol. 315, 1365 - 1368
Bennett and
Plumb, (1995) Textbook of
Medicine, Volume 2, (20th Ed.) WB. Saunders Co. Philadelphia.
Brooking JI.
Ritter SA. Thomas BL, (1992), Psychiatric and Mental Health Nursing,
Churchill Livingstone, Edinburgh
Espino DV. Jules-Bradley AC. Johnston CL. Mouton CP. (1998), Diagnostic approach
to the confused elderly patient, American Family Physician, 57(6):1358-66.
Ferrera
PC. Reicho PR. (1996) Acute confusional migraine and
trauma-triggered migraine. American Journal of Emergency Medicine. 14(3):276-8, 1996 May.
Flaherty
JH. (1998), Psychotherapeutic agents in older
adults. Commonly prescribed and
over-the-counter remedies: causes of confusion. Clinics in Geriatric Medicine, 14(1):101-27.
Forreman
MD, Zane D, (1996), Nursing Strategies for Acute Confusion
in Elders, American Journal of
Nursing, 97 (4) 44 - 49
Jitapunkul S,
Pillay I, Ebrahim S, (1991), The
abbreviated mental test: its use and validity. Age and Ageing, 20 332 - 336
Jones A (1995)
How effective is reality orientation for elderly , confused patients, British
Journal of Nursing, 4 (9) 519 - 522
Jorden and
Torrance (1995), Bionursing: confusion in the elderly, Nursing Standard,
10 (6) 30 - 32
Kumar P. Clark M. (1995) Clinical Medicine, (third ed.)
Bailliere Tindale, London
Kozak-Campbell
C. Hughes AM. (1996) The use of
Functional Consequences Theory in acutely confused hospitalized elderly. Journal
of Gerontological Nursing.
22(1):27-36.
Little JT. Satlin A. Sunderland T. Volicer L. (1995), Sundown syndrome in
severely demented patients with probable Alzheimer's disease. Journal of Geriatric Psychiatry &
Neurology. 8(2):103-6.
Melka A. Tekie-Haimanot R. Assefa M. (1997), Aetiology and outcome of non-traumatic
altered states of consciousness in north western Ethiopia, East African Medical Journal. 74(1):49-53.
Mentes J. Buckwalter K. (1997), Getting back to basics: maintaining
hydration to prevent acute confusion in frail elderly, Journal of Gerontological Nursing, 23(10):48-51.
Miller J. Moore K. Schofield A. Ng'andu N. (1996), A study of discomfort and
confusion among elderly surgical patients, Orthopaedic Nursing. 15(6):27-34, 1996 Nov-Dec.
Miller J. Neelon V. Dalton J. Ng'andu N. Bailey D Jr. Layman E. (1996), The assessment of
discomfort in elderly confused patients: a preliminary study. Journal of Neuroscience Nursing. 28(3):175-82.
Murai T. Toichi M. Sengoku A. (1996), Functional psychosis
mimicking acute confusional state: longitudinal neuropsychological assessment
of an acute and transient psychotic patient. Psychiatry & Clinical
Neurosciences. 50(5):257-60.
Nezu A. Kimura S. Ohtsuki N. Tanaka M. Takebayashi S. (1997), Acute confusional
migraine and migrainous infarction in childhood. Brain & Development. 19(2):148-51.
Sanders P
(1995) Caring for confused people in the general hospital setting, Nursing
Times, 91 (47) 27 - 29
Shaabat A.
(1996), Confusional migraine in
childhood, Pediatric Neurology,
15(1):23-5.
World Health
Organisation, (1992), International
Statistical Classification of Disease and Related Health Problems, 10th
Revision, WHO, Geneva
Answer the
following questions.
1. What
clinical features may lead you to believe a patient is confused?
2. What is
meant by the term primary confusion?
3. Give some
examples of diseases which lead to dementia.
4. List some
conditions which may lead to secondary confusion.
5. How does
the American Psychiatric association describe an acute confusional state?
6. Explain in
pathophysiological terms why the following conditions may cause confusion
i. Obstructive
airways disease ii. Carotid
arterial atherosclerosis
iii Malnutrition iv. Infections
v. Dehydration vi. Hypothermia
7. How would
you distinguish between acute and chronic confusion in a newly admitted
patient.