Delirium
Delirium may be confused with multiple psychiatric disorders or chronic organic brain syndromes because of many overlapping signs and symptoms in common with dementia, depression, psychosis, etc.
[6] In some cases, temporary or symptomatic treatments are used to comfort the person or to facilitate other care (e.g., preventing people from pulling out a breathing tube).
Apart from the general difficulty of recruiting participants who are often unable to give consent, the inherently invasive nature of CSF sampling makes such research particularly challenging.
[26][38][39] A 2018 systematic review showed that, broadly, delirium may be associated with neurotransmitter imbalance (namely serotonin and dopamine signaling), reversible fall in somatostatin, and increased cortisol.
[42][43] Despite progress in the development of magnetic resonance imaging (MRI), the large variety in imaging-based findings has limited our understanding of the changes in the brain that may be linked to delirium.
[42][43] Altogether, these changes in MRI-based measurements invite further investigation of the mechanisms that may underlie delirium, as a potential avenue to improve clinical management of people with this condition.
[44] Since the 1950s, delirium has been known to be associated with slowing of resting-state EEG rhythms, with abnormally decreased background alpha power and increased theta and delta frequency activity.
[68] Key elements of detecting delirium in the ICU are whether a person can pay attention during a listening task and follow simple commands.
[69] The two most widely used are the Confusion Assessment Method for the ICU (CAM-ICU)[70] and the Intensive Care Delirium Screening Checklist (ICDSC).
Prevention approaches include screening to identify people who are at risk, and medication-based and non-medication based (non-pharmacological) treatments.
[82][9] In 1999, Sharon K. Inouye at Yale University, founded the Hospital Elder Life Program (HELP)[83] which has since become recognized as a proven model for preventing delirium.
The volunteer program equips each trainee with the adequate basic geriatric knowledge and interpersonal skills to interact with patients.
Volunteers perform the range of motion exercises, cognitive stimulation, and general conversation[85] with elderly patients who are staying in the hospital.
Delirium may be prevented and treated by using non-pharmacologic approaches focused on risk factors, such as constipation, dehydration, low oxygen levels, immobility, visual or hearing impairment, sleep disturbance, functional decline, and by removing or minimizing problematic medications.
[50][76] Ensuring a therapeutic environment (e.g., individualized care, clear communication, adequate reorientation and lighting during daytime, promoting uninterrupted sleep hygiene with minimal noise and light at night, minimizing room relocation, having familiar objects like family pictures, providing earplugs, and providing adequate nutrition, pain control, and assistance toward early mobilization) may also aid in preventing delirium.
[93] The benefits of hydration reminders and education on risk factors and care homes' solutions for reducing delirium is still uncertain.
[93] For inpatients in a hospital setting, numerous approaches have been suggested to prevent episodes of delirium including targeting risk factors such as sleep deprivation, mobility problems, dehydration, and impairments to a person's sensory system.
[94] Family, friends, and other caregivers can offer frequent reassurance, tactile and verbal orientation, cognitive stimulation (e.g. regular visits, familiar objects, clocks, calendars, etc.
[96] Another approached called the "T-A-DA (tolerate, anticipate, don't agitate) method" can be an effective management technique for older people with delirium, where abnormal behaviors (including hallucinations and delusions) are tolerated and unchallenged, as long as caregiver safety and the safety of the person experiencing delirium is not threatened.
[98] Similarly, people with dementia with Lewy bodies may have significant side effects with antipsychotics, and should either be treated with a none or small doses of benzodiazepines.
[99] Low quality evidence indicates that the antipsychotic medications risperidone or haloperidol may make the delirium slightly worse in people who are terminally ill, when compared to a placebo treatment.
[100] This systematic review only included studies that looked for an independent effect of delirium (i.e., after accounting for other associations with poor outcomes, for example co-morbidity or illness severity).
[100] In the only prospective study conducted in the general population, older persons reporting delirium also showed higher mortality (60% increase).
[101] A large (N=82,770) two-centre study in unselected older emergency population found that delirium detected as part of normal care using the 4AT tool was strongly linked to 30-day mortality, hospital length of stay, and days at home in the year following the 4AT test date.
In the only population-based prospective study of delirium, older persons had an eight-fold increase in dementia and faster cognitive decline.
[109][98] The implications of such an "acquired dementia-like illness" can profoundly debilitate a person's livelihood level, often dismantling his/her life in practical ways like impairing one's ability to find a car in a parking lot, complete shopping lists, or perform job-related tasks done previously for years.
[109] The societal implications can be enormous when considering work-force issues related to the inability of wage-earners to work due to their own ICU stay or that of someone else they must care for.
[117] The Roman author Aulus Cornelius Celsus used the term to describe mental disturbance from head trauma or fever in his work De Medicina.
[118] Sims (1995, p. 31) points out a "superb detailed and lengthy description" of delirium in "The Stroller's Tale" from Charles Dickens' The Pickwick Papers.
For instance, the English medical writer Philip Barrow noted in 1583 that if delirium (or "frensy") resolves, it may be followed by a loss of memory and reasoning power.
