DELIRIUM IN ACUTE CARE 2
Delirium in Acute Care
Lindsey Moeller
Wright State University
Delirium in Acute Care
Definition and Significance of the Problem
Delirium is defined by an acute onset of confusion that waxes and wanes, decreased awareness of environment, and decreased level of consciousness not attributable to an underlying cognitive or medical condition (Catic, 2011; Davis et al., 2013). According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth edition (DSM-V), these are the criteria for the diagnosis. The hallmark of delirium is the fluctuation in level of consciousness (Collier, 2012). The onset is within hours to days with a duration of days to several months depending on the severity, etiology, and treatment.
Delirium occurs in about 30% or one third of patients 70 years of age and greater during hospitalization (Collier, 2012; Davis et al., 2013; Lorenzl, Fusgen & Noachtar, 2012). An estimated 20% of elderly have delirium on admission and there are negative associations with this problem. Patients who experience delirium in the acute care setting have increased length of stays, increased use of long-term care facilities, higher mortality and morbidity, and an increased risk of death within one year. As a result, healthcare cost increase with an estimated 150 million dollars spent annually in the United States (Lorenzl, Fusgen & Noachtar, 2012). It is thought that delirium is underdiagnosed, not always taken seriously in the elderly, and sometimes blamed on old age.
The purpose of this paper is to review the significance, etiology, relevant literature, and implications for Adult-Gerontology Nurse Practitioners (AG-ACNP) in regards to management of delirium in the hospitalized elder. Alcohol withdraw delirium is excluded.
Discussion of Problem
Etiology
Delirium has many etiologies and for this reason can make it challenging for providers to determine the cause. Often times the etiologies are multifactorial. Delirium can be precipitated by medication, inflammation, metabolic disturbances, withdraw from benzodiazepines, sepsis, infection, surgery, dehydration, or malnutrition during a hospitalization (Catic, 2011; Collier, 2012; Khan et al., 2013). Older adults 65 years of age and older who develop delirium have an increased risk of falls, pressure ulcers, use of restraints and medications such as anticholinergic agents. Complications can worsen due to inactivity and decreased appetite from acute confusion. Patients with baseline dementia can also experience an acute decline from baseline mental status while hospitalized.
Medications and polypharmacy are attributed to 39% of cases in hospitalized elderly specifically, but not limited to antidepressants, antihistamines, steroids, anticholinergic agents, benzodiazepines, and opioids (Catic, 2011; Clegg & Young, 2011). Medication associated delirium is one of the most common causes during hospitalization. Patients who take nine or more medications or who take multiple doses per day are high risk. Other contributing factors in the elderly are altered pharmacokinetics such as decreased creatinine clearance, increased plasma drug concentrations, increased volume distribution, and decreased drug metabolism.
Pathophysiology
Perhaps delirium is difficult to understand due to the complexity and multiple etiologies, leading to underdiagnoses and mismanagement. The pathophysiology differs according to the cause. Medication induced delirium is incredibly complex, but it is thought that dopamine excess and acetylcholine deficiency cause neurotransmitter pathways dysfunction (Barr et al., 2013; Clegg & Young, 2011). Several different types of medications such as antihistamines, steroids, digoxin and H2 antagonists increase anticholinergic activity whereas neuroleptics, angiotensin converting enzyme inhibitors, and antiparkinson medications increase dopaminergic activity.
Delirium due to metabolic disturbances may decrease or slow the release of neurotransmitters due to poor function of the neurons (Lorenzl, Fusgen & Noachtar, 2012). Hypoxia, hypoglycemia and hypercalcemia are all examples of metabolic disturbances. On the other hand, when inflammatory processes are the cause of delirium neurotransmitters are slowed by the increased cytokine release. During stressful states there are higher levels of noradrenaline and glucocorticoids in the body, which can also lead to neuronal damage. The elderly may have more than one pathway for delirium at any given time during hospitalization.
Diagnostic and Treatment Issues
Diagnosis and treatment of delirium is challenging in the elderly, but should not be ignored or strictly blamed on their age. It is a clinical diagnosis and relies heavily on knowledge of the clinician, history, physical, medication history and daily assessment during hospitalization (Catic, 2011). The two types of delirium to recognize are hypoactive and hyperactive, but approximately 30%-60% of cases go undiagnosed (Lorenzl, Fusgen & Noachtar, 2012). Hyperactive types can be manifested by agitation, which is the patient a staff nurse is asking to restrain. The hypoactive type is sometimes more subtle, missed more often, and a poor prognostic factor. Patients who have underlying cognitive disorders or mental illnesses such as depression, Parkinson’s disease, dementia, and Alzheimer’s may acquire acute delirium in the face of their chronic disease making recognition difficult.
Treatment of delirium remains ununiformed and challenging in the acute care setting (Eeles, Thompson, McCrow & Pandy, 2013; Lorenzl, Fusgen, Noachtar, 2012). The underlying cause must be treated in order to resolve the delirium, but symptoms of delirium may be treated. How providers treat delirium can vary widely due to assessment skills, knowledge, experience, but overall it continues to be underdiagnosed (Yevchak et al., 2012). Treatment is difficult because determining the cause is often multifactorial and complex.
Symptoms of delirium can be treated by pharmacologic intervention which can be problematic because the elderly are already are at risk for polypharmacy (Lorenzl, Fusgen, & Noachtar, 2012). Non-pharmacologic treatment of delirium is not always used before reverting to pharmacologic therapy. Hyperactive delirium is sometimes mismanaged with benzodiazepines or sedatives, which may further worsen or lengthen the acute process.
Relevant Research and Guidelines
Sedative medications are commonly used during inpatient elderly stays for various reasons. Beers criteria are a published list of medications to avoid in the elderly (Rothberg et al., 2013). A retrospective cohort and case-controlled studies examined the association between Beers criteria sedative medications and delirium in hospitalized elderly patients with common problems such as acute myocardial infarction, chronic obstructive pulmonary disease, community-acquired pneumonia, congestive heart failure, ischemic stroke, and urinary tract infections (Rothberg et al., 2013). All patients age 65 years of age or greater admitted to over 374 United States hospitals between September 2003 and June 2005 with the previous listed problems were included. Inclusion criteria were initiation of an antipsychotic or restraints on day three of admission or after. There were 225,028 participants with approximately 72% white and 58% female with an average age of 82. Findings were a positive correlation between delirium in patients who received diphenhydramine, short and long acting benzodiazepines, and promethazine. Amitriptyline and muscle relaxants were not associated with delirium. Sedating medications specifically benzodiazepines, diphenhydramine, and promethazine should be avoided or used with extreme caution in hospitalized patients age 65 and older (Rothberg et al., 2013). There were several limitations such as medications used for incorrect indications such as benzodiazepines administered for agitated delirium, lack of specific dosages reported, hypoactive delirium underreported, and variation of reporting among hospitals.
Short and long acting benzodiazepines have been used to treat delirium in the inpatient setting. A systematic review examined the efficacy of benzodiazepines in the acute treatment of delirium (Loneergan, Luxenberg, & Sastre, 2009). Inclusion criteria for studies were pre and post assessments of delirium, randomized controlled trials, and placebo-controlled trials. The populations were adults who developed delirium during hospitalization excluding alcohol withdraw or identified reversible causes such as pain or hypoxia and met DSM-III or DSM-IV criteria. One study met inclusion criteria in the systematic review with one hundred and six medical/surgical mechanically ventilated patients included. The Confusion Assessment Method of the Intensive Care Unit (CAM-ICU) was used to assess for delirium. Delirium was treated in 52 patients with dexmedotomidine and 51 patients received lorazepam continuous intravenous infusions for sedation. The number of delirium and coma free days was less with dexmedotomidine in comparison to lorazepam. Benzodiazepines are not recommended for the treatment of delirium (Loneergan, Luxenberg, & Sastre, 2009). Limitations were only one study met inclusion criteria, lack of ability to generalize to practice outside of the intensive care unit, small sample size, and the study that did meet inclusion criteria only studied lorazepam instead of other benzodiazepines in the treatment of delirium.
Quetiapine and haloperidol have also been used in the management of delirium, but there is concern for adverse side effect such as extrapyramidal side effects. A seven day prospective, double-blind randomized control trial compared tolerance as well as efficacy of quetiapine and haloperidol in the treatment of delirium (Maneeton, Maneeton, Srisurapanont, & Chittawatanarat, 2013). Fifty-two hospitalized patients (35 males and 17 females) between the ages of 18-75 both male and female at Chiang Mai University Hospital in Thailand from June 2009-April 2011. DSM-IV criteria for delirium, a positive CAM score, and a psychiatric consult were also inclusion criteria. The subjects were randomized and received 25-100 mg/day of quetiapine (n=24) or 0.5-2.0 mg/day of haloperidol (n=28). No significant difference in overall response, sleep time, or hypersomnia between the two groups. Low-dose quetiapine or haloperidol are appropriate agents for AG-ACNP’s to use in the treatment of delirium. Limitations to this study are small sample size, not specific to certain diagnoses, and not specific to the elderly population.
Clinical practice guidelines for the treatment of hospital acquired delirium in the intensive care unit (ICU) are available for AG-ACNP’s to reference. The guidelines were updated and released in 2013 by the Society of Critical Care Medicine and focused on management of delirium, pain and sedation in adult ICU patients. The review committee had 20 members, were from multiple disciplines with guideline development skills, and multiple institutions (Barr et al., 2013). Recommendations include there are no data to support the use of haloperidol or antipsychotics to prevent delirium. Antipsychotics may reduce the length of delirium, but not haloperidol. Obtain a baseline electrocardiogram for QT interval measurement when initiating antipsychotics, monitor the QT interval, and avoid these medications in patients with a history of torsade’s or if at high risk for development. Continuous infusions of benzodiazepines are not recommended for delirium, but continuous intravenous dexmedetomidine are acceptable. Further research data are needed for the use of haloperidol and antipsychotics in and out of the ICU for the treatment of delirium.
Role of Adult-Gerontology Acute Care Nurse Practitioner’s in Managing Delirium
The AG-ACNP have a large role in managing delirium in the hospitalized older adult in and out of the ICU. Prevention and recognition are primary responsibilities when caring for patients in the acute care setting. AG-ACNP should stay up-to-date on the latest research and guidelines for the treatment of delirium in the older adult. Participating in research at all levels as well as sharing knowledge with peers, physicians, and bedside nursing staff is crucial. Collaborating with nursing staff to identify patients at high risk for delirium, perform daily standardized delirium assessments, promote strategies to maintain homeostasis, and a careful review prescribed medications.
AG-ACNP’s should use a systematic approach to diagnose delirium such the Confusion Assessment Method (CAM). It is a well-studied assessment tool with approximately 94-100% sensitivity and 90-95% specificity for delirium diagnosis (Khan, 2013; Lorenzl, Fusgen & Noachtar, 2012). This tool addresses onset, fluctuation, inattention, level of consciousness, and clarity of thinking. This needs to be performed by the AG-ACNP and the staff nurse for comparison and discussion on rounds.
After diagnosis, the AG-ACNP determines the appropriate therapy non-pharmacologic or pharmacologic and sometimes a combination is necessary. Treatment begins with evaluation of the cause before development of the treatment plan. Fluids, nutrition, re-orientation, discontinuation of potential contributing medications, and creating a calm environment are examples of non-pharmacologic interventions (Lorenzl, Fusgen, & Noachtar, 2012). Prescribing haloperidol or an antipsychotic at the lowest dose appropriate are possible pharmacologic therapies the AG-ACNP may prescribe.
Summary
The AG-ACNP can help bridge the gap between misdiagnosis and treatment of delirium in the older adult while hospitalized. Delirium is highly individualized with varying clinical manifestations, etiologies, and durations. More research is needed for the treatment and prevention of delirium. With education and implementation of current guidelines into practice, rates of recognition can improve with the goal of identifying and treating the underlying cause. Eliminating any unnecessary or controllable factors is also important. Current evidence does not support the use of medication prophylaxis in the non-alcohol withdraw delirium, but The Society of Critical Care Medicine latest recommendations agree with the use of intravenous dexmedetomidine in the ICU for treatment (Barr et al., 2013). Benzodiazepines are not supported for delirium treatment, but minimal doses of haloperidol or an antipsychotic may be helpful to reduce the length of delirium (Maneeton et al., 2013). Use pharmacologic therapies judiciously and continuously monitor risk versus benefit.
References
Barr, J., Fraser, G., Puntillo, K., Ely, E., Gelinas, C., Dasta, J., Davidson, J., Devlin, J., Kress, J., Joffee, A., Coursin, D., Herr, D., Tung, A., Robinson, H., Fontaine, D., Ramsay, M., Riker, R., Sessler, C., Pun, B., Skrobik, Y., & Jaeschke, R. (2013). Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit. Critical Care Medicine, 41(1), 263-306. doi: 10.1097/CCM.0b013e3182783b72
Catic, A. (2011). Identification and management of in-hospital drug-induced delirium in older patients. Drugs Aging, 28(9), 737-748.
Clegg, A., & Young, J. (2011). Which medications to avoid in people at risk for delirium: a systematic review. Age and Ageing, 40, 23-29. doi: 10.1093/ageing/afq140
Collier, R. (2012). Hospital-induced delirium hits hard. Canadian Medical Association Journal, 184(1), 23-24. doi: 10.1053/cmaj.109-4069
Davis, D., Kreisel, S., Terrera, G., Hall, A., Morandi, A., Boustani, M., Neufeld, K., Lee, H., MacLullich, A., & Brayne, C. (2013). The epidemiology of delirium: Challenges and opportunities for population studies. The American Journal of Geriatric Psychiatry, 21(12), 1173-1189. doi:10.1016/j.jagp.2013.04.007
Eeles, E., Thompson, L., McCrow, J., & Pandy, S. (2013). Innovations in aged care, management of delirium in medicine: Experience of a close observation unit. Australian Journal of Ageing, 32(1), 60-63. doi: 10.1111/ajag.12007