الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The main four domains for diagnosing delirium as listed by the American Psychiatric Association‘s Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-V) are; disturbance of consciousness, change in cognition, development over a short period, and fluctuation.
Several symptoms of delirium also occur in other psychiatric conditions as in dementia and depression and these psychiatric conditions may also coexist in the same patient, which can make the diagnosis problematic. Distinguishing delirium from other psychiatric problems is crucial as it can be the first indicator of a serious medical problem, which can be treatable, and because it has been associated with poor outcomes.
Delirium is a nonspecific but generally reversible manifestation of acute illness that appears to have many causes. The pathophysiology of delirium per se is ill defined but there are a number of theories regarding the pathological changes in the brain that result in and from delirium.
Delirium has a wide range of presentations. It can be divided accordingly into hyperactive delirium, hypoactive
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delirium or mixed clinical picture of both subtypes. Each is distinguishable by psychomotor behavior and arousal.
Among medical ICU patients, delirium has shown to be a strong predictor of longer duration of mechanical ventilation, longer length of ICU stay, higher costs, prolonged neuropsychological dysfunction, and even death.
In practical terms, the risk factors for delirium can be divided into the following categories: (1) host factors, (2) the acute illness itself, (3) iatrogenic and precipitating factors (4) underlying co-morbidities and (5) environmental factors.
A number of instruments are available to help in detection and diagnosis of delirium in critically ill patients during their ICU stay. The importance of using these instruments lies in that most cases of delirium in the ICU may go undetected. In a systematic review since 2007, six validated instruments to assess delirium in critically ill patients were identified. These included the Cognitive Test for Delirium, abbreviated Cognitive Test for Delirium, Confusion Assessment Method for the Intensive Care Unit (CAM-ICU), Intensive Care Delirium Screening Checklist (ICDSC), Neelon and Champagne Confusion Scale, and the Delirium Detection Score. The ICDSC and CAM-ICU are the most studied & validated instruments.
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Diagnosis of delirium is a two-step process. Level of arousal is first measured with the use of a standardized sedation scale, like the Richmond Agitation-Sedation Scale (RASS) or the Sedation-Agitation Scale (SAS), then assessment of delirium is performed using CAM-ICU or ICDSC.
There are two main approaches to prevention of delirium: non-pharmacologic and pharmacologic therapies. Three risk-factors in particular—sedatives, immobility and sleep disruption—are widespread in the ICU as a result of clinical practice habits in most ICUs and therefore serve as important targets for delirium prevention. A bundled approach combining evidence-based practices in sedation management, ventilator weaning, delirium management and early mobility and exercise, which is referred to as the ABCDE approach, has been proposed to improve multiple outcomes, including preventing and reducing the duration of delirium in the ICU.
Pharmacologic therapy for delirium in the ICU may be a helpful adjunct to the needed multicomponent approach to patient care. Pharmacologic strategies primarily involve the use of dopamine antagonists – typical antipsychotic as haloperidol and atypical antipsychotics as olanzapine, quetiapine, risperidone, aripiprazol, and ziprasidone– or Alpha-2 agonists with a sedative effect as dexmedetomidine and clonidine.