Drug-induced delirium. Incidence, management and prevention

Melatonin intervention to prevent delirium in hospitalized patients: A meta-analysis

BACKGROUND

Evaluation of the effectiveness of melatonin is necessary to prevent the development of delirium in hospitalized patients. Melatonin (N-acetyl-5-methoxytryptamine) is a hormone produced by the pineal gland of the brain from the amino acid tryptophan. Synthetic melatonin supplements have been used for various medical conditions, especially sleep-related diseases, and have proved to be successful.

AIM

To determine the effect of melatonin on the prevention of delirium in hospitalized patients.

METHODS

A literature search of the CNKI, Wanfang Database, VIP Database, China Biomedical Literature Database, PubMed, Embase, Cochrane Library, Web of Science, and other databases was conducted. The CNKI, Wanfang Database, VIP Database (VIP), and China Biomedical Literature Database were searched for Chinese studies, and PubMed, Embase, Cochrane Library, Web of Science and other databases were searched for international studies. It will be established in June 2021 in a randomized controlled trial (RCT) whether melatonin treatment for 6 mo prevents delirium in hospitalized patients. Literature screening, quality review, and data extraction were carried out using the Cochrane Manual 5.1.0 systematic evaluation method, and Stata 15.0 software and Review Manager 5.3 were used for meta-analysis and processing.

RESULTS

A total of 18 new RCT articles and 18 experimental subjects were identified. The results of the meta-analysis showed that following the occurrence of delirium, melatonin reduced the incidence of delirium in patients (RR = 0.69, 95%CI: 0.60-0.80), which is of significance, but heterogeneity was significant I² = 62%. Subgroup analysis was performed to examine the source of heterogeneity, and it was found that different patient types were the source of heterogeneity; the research on subgroup analysis was of high quality and homogeneous. To determine the reliability and robustness of the research results, a sensitivity analysis was carried out. The results showed that after excluding individual studies one by one, the effect size was still within 95%CI, which strengthened the reliability of the original meta-analysis results. Melatonin has a significant preventive effect on delirium in hospitalized medical patients [RR = 0.60, 95%CI: 0.47-0.76), P < 0.001].

CONCLUSION

Melatonin can reduce the rate of delirium in medical patients, and the role of melatonin in reducing the incidence of delirium in surgical patients and critical care unit patients requires further study.

Hospital-treated deliberate self-poisoning patients: Drug-induced delirium and clinical outcomes

OBJECTIVE

Drug-induced delirium has been attributed to opioid, benzodiazepine, antipsychotic, antihistaminic and anticholinergic drug groups at therapeutic doses. Delirium also occurs in hospital-treated self-poisoning (at supra-therapeutic doses), although the causative drug classes are not well established and co-ingestion is common. We tested the magnitude and direction of association of five major drug groups with incident cases of delirium.

METHODS

A retrospective longitudinal cohort (n = 5131) study was undertaken of deliberate and recreational/chronic misuse poisoning cases from a regional sentinel toxicology unit. We described ingestion and co-ingestion patterns and estimated the unadjusted and adjusted odds for developing a drug-induced delirium. We also estimated the odds of drug-induced delirium being associated with three outcomes: intensive care unit admission, general hospital length of stay and discharge to home.

RESULTS

Drug-induced delirium occurred in 3.9% of cases (n = 200). The unadjusted odds ratios for development of delirium were increased for anticholinergics 10.79 (5.43-21.48), antihistamines 6.10 (4.20-8.84) and antipsychotics 2.99 (2.20-4.06); non-significant for opioids 1.31 (95% confidence interval = [0.81, 2.13]); and reduced for benzodiazepines 0.37 (0.24-0.58); with little change after adjustment for age, gender and co-ingestion. Delirium was associated with intensive care unit admission, longer length of stay and discharge destination.

CONCLUSION

Drug-induced delirium was uncommon in this population. Co-ingestion was common but did not alter the risk. In contrast to drug-induced delirium at therapeutic doses in older populations, opioids were not associated with delirium and benzodiazepines were protective. Drug-induced delirium required increased clinical services. Clinical services should be funded and prepared to provide additional supportive care for these deliriogenic drug group ingestions.

Hospitalizations of older people in an emergency department related to potential medication-induced hyperactive delirium: a cross-sectional study

Background Although delirium is one of the most common adverse drug reactions observed in hospitalized older people, it remains underdiagnosed. Aim To estimate the prevalence of hospitalization of older people with potential medication-induced hyperactive delirium in the emergency department (ED); to identify the risk factors and the medicines frequently associated with the occurrence of the syndrome. Method A cross-sectional, retrospective study was performed with older people (age ≥ 60) admitted in 2018 to a Brazilian ED. The hospitalizations with suspected hyperactive delirium were screened with the aid of trigger-tools: International Code of Diseases-10th Revision, intra-hospital prescriptions of antipsychotics, and trigger-words related to the syndrome. A chart-review and medication review were developed to establish the causality assessment between adverse event and medicine. Logistic regression was used to determine risk factors for occurrence. Results Among the hospitalizations included, 67.5% (193/286) were screened by at least one trigger-tool. Of these, potential medication-induced hyperactive delirium was observed in 26.0% (50/193). The prevalence estimated in the ward was 17.5% (50/286). Opioids (31.9%), benzodiazepines (18.8%) and corticosteroids (10.6%) were the commonest medicines associated with delirium. Long-lived patients (p = 0.005), potentially inappropriate medicines (PIMs) (p = 0.025), and high weighted deliriogenic load (p = 0.014) were associated with potential medication-induced hyperactive delirium. Conclusion Approximately one in six hospitalizations of older people in the ED showed potential medication-induced hyperactive delirium. Data suggest PIMs and high weighted deliriogenic load, rather than polypharmacy or anticholinergic burden, are considered the most important characteristics of pharmacotherapy associated with avoidable hyperactive delirium among long-lived patients.

Identifying frequent drug combinations associated with delirium in older adults: Application of association rules method to a case-time-control design

BACKGROUND

Older adults are at an increased risk of delirium because of age, polypharmacy, multiple comorbidities, frailty, and acute illness. Although medication-induced delirium in older adults is well understood, limited population-level evidence is available, particularly on combinations of medications associated with delirium in older adults.

OBJECTIVES

We aimed to apply association rule analysis to identify drug combinations contributing to delirium risk in adults aged 65 and older using a case-time-control design.

METHOD

We sourced a nationwide representative sample of New Zealander's aged ≥65 years from the pharmaceutical collections and hospital discharge information. Prescription records (2005-2015) were obtained from New Zealand pharmaceutical collections (Pharms). Medication exposures were coded as binary variables (exposed vs. not exposed) at the individual drug level. All medications, including antimicrobials, antihistamines, diuretics, opioids, and nonsteroidal anti-inflammatory medications, were considered drugs of interest. The first-time coded diagnosis of delirium was extracted from the National Minimal Dataset (NMDS). A unique patient identifier linked the prescription dataset to the event dataset to set up a case-time-control cohort, indexed at the first delirium event. Association rules were then applied to identify frequent drug combinations in the case and the control periods (l-day with a 35-day washout period) that are statistically associated with delirium, and the association was tested by computing a time-trend adjusted matched odds-ratio (MOR) and its 95% confidence interval (CI).

RESULTS

We identified 28 503 individuals (mean age 84.1 years) from 2005 to 2015 with delirium. Our combined association rule and case-time-control analysis identified several drug classes, including antipsychotics, benzodiazepines, opioids, and diuretics associated with delirium. Our analysis also identified frequently used drug combinations that are associated with delirium. Examples include combined exposures to quetiapine and furosemide (MOR = 6.17; 95%CI = [2.05-18.54]), haloperidol (MOR = 4.81; 95%CI = [3.16-6.69]), combined exposures to furosemide, omeprazole, and lorazepam (MOR = 3.94; 95%CI = [3.03-5.10]), and fentanyl exposure (MOR = 3.46; 95%CI [2.05-9.21]).

CONCLUSION

The association rule method applied to a case-time-control design is a novel approach to identifying drug combinations contributing to delirium with adjustment for any temporal trends in exposures. The study provides new insight into the combination of medicines linked to delirium.

A longitudinal study on delirium in nursing homes

OBJECTIVE

To investigate the evolution of delirium of nursing home (NH) residents and their possible predictors.

DESIGN

Post-hoc analysis of a prospective cohort assessment.

SETTING

Ninety NHs in Switzerland.

PARTICIPANTS

Included 14,771 NH residents.

MEASUREMENTS

The Resident Assessment Instrument Minimum Data Set and the Nursing Home Confusion Assessment Method were used to determine follow-up of subsyndromal or full delirium in NH residents using discrete Markov chain modeling to describe long-term trajectories and multiple logistic regression analyses to determine predictors of the trajectories.

RESULTS

We identified four major types of delirium time courses in NH. Increasing severity of cognitive impairment and of depressive symptoms at the initial assessment predicted the different delirium time courses.

CONCLUSION

More pronounced cognitive impairment and depressive symptoms at the initial assessment are associated with different subsequent evolutions of delirium. The presence and evolution of delirium in the first year after NH admission predicted the subsequent course of delirium until death.

The evaluation and management of delirium among older persons

This article reviews the pathophysiology, prevalence, incidence, and consequences of delirium, focusing on the evaluation of delirium, the published models of care for prevention in patients at risk of delirium, and management of patients for whom delirium is not preventable. Evidence on why physical restraints should not be used for patients with delirium is reviewed. Current available evidence on antipyschotics does not support the role for the general use in the treatment of delirium. An example of a restraint-free, nonpharmacologic management approach [called the TADA approach (tolerate, anticipate, and don't agitate)] is presented.

Assessment of role of perioperative melatonin in prevention and treatment of postoperative delirium after hip arthroplasty under spinal anesthesia in the elderly

CONTEXT

Little is known about the relationship between sedative drugs used preoperatively and postoperative delirium. Melatonin is a drug used to sedate patients preoperatively and is hypothesized by recent works to have a curative effect on postoperative delirium.

AIMS

The incidence of postoperative delirium will be tested if affected by three different sedative drugs including melatonin.

SETTINGS AND DESIGN

Controlled randomized doubleblind study.

PATIENTS AND METHODS

Three-hundred patients aged>65 years scheduled for hip arthroplasty under spinal anesthesia were randomly distributed to one of the four groups. Group 1 (control) received nothing for sedation. Group 2 (melatonin) received 5 mg melatonin. Group 3 (midazolam) received 7.5 mg midazolam. Group 4 (clonidine) received 100 μg clonidine. These medications were given orally at sleep time at night of operation and another dose 90 min before operative time. Patients who developed postoperative delirium received 5 mg of melatonin 9 pm for three successive days in a trial to treat delirium.

STATISTICAL ANALYSIS USED

Statistical analysis was done using the SPSS Software (version 13).

RESULTS

Total of 222 patients completed the study. Percentage of postoperative delirium in the control group was 32.65% (16/49 patients). The melatonin group showed a statistically significant decrease in the percentage of postoperative delirium to 9.43% (5/53 patients). Melatonin was successful in treating 58.06% of patients suffered postoperative delirium (36/62 patients) with no difference between different groups.

CONCLUSIONS

Postoperative delirium is affected with the drug used for preoperative sedation. Melatonin was successful in decreasing postoperative delirium when used preoperatively and in treating more than half of patients developed postoperative delirium when used for three postoperative nights.

Delirium in the nursing home patients seen in the emergency department

OBJECTIVES

To determine whether nursing home patients are more likely than non-nursing home patients to present to the emergency department (ED) with delirium and to explore how variations in their delirium risk factor profiles contribute to this relationship.

DESIGN

Prospective cross-sectional study.

SETTING

Tertiary care academic ED.

PARTICIPANTS

Three hundred forty-one English-speaking patients aged 65 and older.

MEASUREMENTS

Delirium status was determined using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) administered by trained research assistants. Multivariable logistic regression was used to determine whether nursing home residence was independently associated with delirium. Adjusted odds ratios (ORs) with their 95% confidence intervals (95% CIs) were reported.

RESULTS

Of the 341 patients enrolled, 58 (17.0%) resided in a nursing home and 38 (11.1%) were considered to have delirium in the ED. Of the 58, (22 (37.9%) nursing home patients and 16 of 283 (5.7%) non-nursing home patients had delirium; unadjusted OR=10.2, 95% CI=4.9-21.2). After adjusting for dementia, a Katz activity of daily living score less than or equal to 4, hearing impairment, and the presence of systemic inflammatory response syndrome, nursing home residence was independently associated with delirium in the ED (adjusted OR=4.2, 95% CI=1.8-9.7).

CONCLUSION

In the ED setting, nursing home patients were more likely to present with delirium, and this relationship persisted after adjusting for delirium risk factors.

Benzodiazepine and opioid use and the duration of intensive care unit delirium in an older population

OBJECTIVE

There is a high prevalence of delirium in older medical intensive care unit (ICU) patients and delirium is associated with adverse outcomes. We need to identify modifiable risk factors for delirium, such as medication use, in the ICU. The objective of this study was to examine the impact of benzodiazepine or opioid use on the duration of ICU delirium in an older medical population.

DESIGN

Prospective cohort study.

SETTING

Fourteen-bed medical intensive care unit in an urban university teaching hospital.

PATIENTS

304 consecutive admissions age 60 and older.

INTERVENTIONS

None.

MAIN OUTCOME MEASUREMENTS

The main outcome measure was duration of ICU delirium, specifically the first episode of ICU delirium. Patients were assessed daily for delirium with the Confusion Assessment Method for the ICU and a validated chart review method. Our main predictor was receiving benzodiazepines or opioids during ICU stay. A multivariable model was developed using Poisson rate regression.

RESULTS

Delirium occurred in 239 of 304 patients (79%). The median duration of ICU delirium was 3 days with a range of 1-33 days. In a multivariable regression model, receipt of a benzodiazepine or opioid (rate ratio [RR] 1.64, 95% confidence interval [CI] 1.27-2.10) was associated with increased delirium duration. Other variables associated with delirium duration in this analysis include preexisting dementia (RR 1.19, 95% CI 1.07-1.33), receipt of haloperidol (RR 1.35, 95% CI 1.21-1.50), and severity of illness (RR 1.01, 95% CI 1.00-1.02).

CONCLUSIONS

The use of benzodiazepines or opioids in the ICU is associated with longer duration of a first episode of delirium. Receipt of these medications may represent modifiable risk factors for delirium. Clinicians caring for ICU patients should carefully evaluate the need for benzodiazepines, opioids, and haloperidol.

Psychiatric issues in palliative care: Recognition of delirium in patients enrolled in hospice care

Objectives:

Delirium is prevalent, difficult to assess, under-recognized, and undertreated in hospice and palliative care settings. Furthermore, it is associated with significant morbidity and mortality. Under-recognition of delirium results in under-treatment and increased suffering. The intent of this study was to retrospectively evaluate the recognition of delirium in a large cohort of hospice patients by interdisciplinary hospice care teams.

Methods:

A retrospective chart review of 2,716 patients receiving hospice care was conducted in order to determine the baseline rate of recognition of delirium in patients with advanced, life-threatening illnesses by front-line hospice clinicians. Documentation of “delirium” as either a diagnosis or problem was used as an estimate of how often these disorders were considered significant issues by the treating interdisciplinary team.

Results:

Of the patients receiving home/long-term care, 17.8% (386/2168) had delirium documented as a diagnosis or significant problem. The presence of recognized delirium in this setting was associated with significant differences in marital status, ethnicity, hospice diagnosis, and age. Total length of hospice care was also significantly longer. Of patients receiving inpatient care, 28.3% (614/548) had delirium documented as a diagnosis or significant problem. Recognized delirium in this setting was associated with significant differences in gender, ethnicity, hospice diagnosis, and length of inpatient stay.

Significance of results:

If documentation is representative of the care that the interdisciplinary teams provide, delirium of any kind appears to be under-recognized in this population. In fact, it is on the low end of prevalence estimates in the literature. Improved delirium assessment is needed in order to minimize the impact of delirium on patients living with advanced, life-threatening illnesses and their caregivers.

Delirium: guidelines for general hospitals

OBJECTIVE

Delirium is highly prevalent in general hospitals but remains underrecognized and undertreated despite its association with increased morbidity, mortality, and health services utilization. To enhance its management, we developed guidelines covering all aspects, from risk factor identification to preventive, diagnostic, and therapeutic interventions in adult patients.

METHODS

Guidelines, systematic reviews, randomized controlled trials (RCT), and cohort studies were systematically searched and evaluated. Based on a synthesis of retrieved high-quality documents, recommendation items were submitted to a multidisciplinary expert panel. Experts scored the appropriateness of recommendation items, using an evidence-based, explicit, multidisciplinary panel approach. Each recommendation was graded according to this process' results.

RESULTS

Rated recommendations were mostly supported by a low level of evidence (1.3% RCT and systematic reviews, 14.3% nonrandomized trials vs. 84.4% observational studies or expert opinions). Nevertheless, 71.1% of recommendations were considered appropriate by the experts. Prevention of delirium and its nonpharmacological management should be fostered. Haloperidol remains the first-choice drug, whereas the role of atypical antipsychotics is still uncertain.

CONCLUSIONS

While many topics addressed in these guidelines have not yet been adequately studied, an explicit panel and evidence-based approach allowed the proposal of comprehensive recommendations for the prevention and management of delirium in general hospitals.

Meta-review of high-quality systematic reviews of interventions in key areas of liaison psychiatry

BACKGROUND

When planning and delivering a liaison psychiatry service it is important to have an understanding of the research evidence supporting the use of interventions likely to be delivered by the service.

AIMS

To identify high-quality systematic reviews for all interventions in three defined areas of liaison psychiatry, to summarise their clinical implications and to highlight areas where more research is needed. The three areas were the psychological effects of physical illness or treatment, somatoform disorders and self-harming behaviour.

METHOD

Computerised database searching, secondary reference searching, hand-searching and expert consultation were used to identify relevant systematic reviews. Studies were reliably selected, and quality-assessed, and data were extracted and interpreted by two reviewers.

RESULTS

We found 64 high-quality systematic reviews. Only 14 reviews included meta-analyses.

CONCLUSIONS

Many areas of liaison psychiatry practice are not based on high-quality evidence. More research in this area would help inform development and planning of liaison psychiatry services.

Association Between Psychoactive Medications and Delirium in Hospitalized Patients: A Critical Review

Psychoactive medications are often reported as delirium risk factors in hospitalized patients, and delirium induced by medication is potentially avoidable. The authors critically reviewed the evidence for a role of medications in delirium etiology. Only a few positive associations were noted. Use of psychoactive medications, considered together as a single variable, and use of opioids increased the risk of delirium. Data were scarce and sometimes conflicting, and methodological limitations were often present. The suspected association between psychoactive drugs and delirium cannot be unambiguously confirmed with current epidemiological evidence. The interpretation of these results must take into account the limitations of published studies, which should be addressed in future research.

Effect of Person-Centered Showering and the Towel Bath on Bathing-Associated Aggression, Agitation, and Discomfort in Nursing Home Residents with Dementia: A Randomized, Controlled Trial

OBJECTIVES

To evaluate the efficacy of two nonpharmacological techniques in reducing agitation, aggression, and discomfort in nursing home residents with dementia. The techniques evaluated were person-centered showering and the towel bath (a person-centered, in-bed bag-bath with no-rinse soap).

DESIGN

A randomized, controlled trial, with a usual-care control group and two experimental groups, with crossover.

SETTING

Nine skilled nursing facilities in Oregon and six in North Carolina.

PARTICIPANTS

Seventy-three residents with agitation during bathing (69 completed the trial) and 37 nursing assistants who bathed them.

MEASUREMENTS

Agitation and aggression were measured using the Care Recipient Behavior Assessment; discomfort was measured using a modification of the Discomfort Scale for Dementia of the Alzheimer Type. Raters who were blinded to subject status coded both from videotaped baths. Secondary measures of effect included bath duration, bath completeness, skin condition, and skin microbial flora.

RESULTS

All measures of agitation and aggression declined significantly in both treatment groups but not in the control group, with aggressive incidents declining 53% in the person-centered shower group (P<.001) and 60% in the towel-bath group (P<.001). Discomfort scores also declined significantly in both intervention groups (P<.001) but not in the control group. The two interventions did not differ in agitation/aggression reduction, but discomfort was less with the towel bath (P=.003). Average bath duration increased significantly (by a mean of 3.3 minutes) with person-centered showering but not with the towel bath. Neither intervention resulted in fewer body parts being bathed; both improved skin condition; and neither increased colonization with potentially pathogenic bacteria, corynebacteria, or Candida albicans.

CONCLUSION

Person-centered showering and the towel bath constitute safe, effective methods of reducing agitation, aggression, and discomfort during bathing of persons with dementia.

Benzodiazépines : conséquences sur le fonctionnement mnésique des personnes âgées

Des études effectuées chez une population de volontaires sains en administration unique indiquent que les benzodiazépines (BZD) sont connues pour induire des déficits en mémoire. Cette population étudiée ne correspond toutefois pas avec celle qui consomme régulièrement ces substances soit les personnes âgées. Peu d’études ont été faites auprès de cette population cible afin de déterminer l’impact des BZD sur leur mémoire. Par contre, il existe des évidences suggérant aussi qu’il existe des conséquences importantes sur le fonctionnement de la mémoire des personnes âgées qui prennent des BZD. Les données actuelles vont même jusqu’à suggérer que les BZD exacerbent les déficits de mémoire chez les personnes âgées. Cela pourrait même constituer un facteur de risque précipitant le déclin cognitif et augmentant ainsi le risque de développer une démence.

Cost-effectiveness analysis of pharmaceutical care in a medicare drug benefit program

OBJECTIVES

Although there has recently been substantial interest in a Medicare drug benefit program, little attention has focused on ensuring improved access to medication monitoring for Medicare beneficiaries. Using a societal perspective, we evaluated the impact pharmacists could have on inappropriate prescribing, patient compliance, and medication-related morbidity and mortality within a Medicare drug benefits program.

METHODS

A cost-effectiveness analysis from a societal perspective was performed. A comprehensive MEDLINE search for relevant literature identified data sources and model parameters.

RESULTS

In the base case, a pharmaceutical care benefit in the elderly population would cost US dollars 2100 (year 2000 prices) per life-year saved, which is highly cost-effective. Reasonable changes in model parameters did not raise the cost-effectiveness ratio above US dollars 13000 per life-year saved.

CONCLUSION

Despite limitations in both the quantity and the specificity of data available, pharmaceutical care appears to be a highly cost-effective augmentation to a Medicare drug benefit program. This result is robust to model parameter changes. This model is conservative in that it does not include ongoing benefits from medication monitoring or increased elderly drug utilization and polypharmacy as the Medicare drug program is phased in.

Delirium: an important (but often unrecognized) clinical syndrome

Delirium is a clinical syndrome characterized by the acute onset of a disturbance in consciousness accompanied by a reduced ability to focus, sustain, or shift attention. It may foreshadow impending death in as many as 25% of hospitalized inpatients and may be a source of significant morbidity in those who present with this syndrome. The disorder may go unrecognized by hospital staff as well as those close to an affected individual, and this oversight may lead to poorer outcomes including longer lengths of stay in acute care hospitals, the need for nursing home placement, prolonged cognitive disturbances, and protracted disability. This paper will address this complex condition, focusing on its history, definition, epidemiology, pathophysiology, recognition, risk factors, and clinical quantification. Its prevention and treatment will be covered elsewhere in this journal.

Lithium toxicity: an iatrogenic problem in susceptible individuals

OBJECTIVE

Lithium toxicity, manifesting primarily as neurotoxicity, is a significant health problem and is primarily iatrogenic in nature. Despite 50 years of medical experience with lithium, factors contributing to the development of severe neurotoxicity remain poorly documented. We hypothesized that severe neurotoxicity represents the most clinically significant manifestation of lithium toxicity. We proposed that this occurs primarily in the context of chronic therapeutic administration ('chronic poisoning'), rather than in the context of an overdose. Furthermore we hypothesized that patients who developed chronic poisoning did so in the presence of identifiable factors which predictably impair lithium clearance.

METHOD

A retrospective analysis of 97 cases of lithium poisoning, treated at a regional centre over a 13-year period was performed. Demographic data and factors considered likely to relate to the risk of developing lithium toxicity were recorded. Patients were classified according to mode of poisoning (acute, acute on chronic, or chronic) and according to severity of neurotoxicity (nil, mild, moderate, severe). The risk of developing severe neurotoxicity as a result of each mode of poisoning was assessed. The association between various risk factors and the development of chronic poisoning was assessed using a logistic regression model.

RESULTS

Twenty-eight cases were rated as suffering severe neurotoxicity; in 26 this developed in the context of chronic poisoning and in two in the context of acute on chronic poisoning. All patients who developed severe neurotoxicity had at least one putative risk factor present, regardless of mode of poisoning. Length of stay was significantly longer for cases with severe neurotoxicity compared to those without severe neurotoxicity (12 vs. 2 days, P < 0.001). Peak serum lithium concentrations were significantly higher in cases with severe neurotoxicity compared to those without (2.3 vs. 1.6 mmol/L, P = 0.02). Patients presenting with chronic poisoning had a substantially higher risk of severe neurotoxicity than those presenting after an overdose of lithium (Odds Ratio [OR] 136, 95% CI 23-1300). A logistic regression model showed three factors contributed independently to the risk of chronic poisoning. These were: nephrogenic diabetes insipidus (adjusted OR 26.96, 95% CI 2.89-251.94), age over 50 years (adjusted OR 6.20, 95% CI 1.36-28.32) and thyroid dysfunction (adjusted OR 9.30, 95% CI 1.36-63.66). A fourth factor, baseline endogenous creatinine clearance below normal limits, was significant at the P = 0.05 level (adjusted OR 6.49, 95% CI 0.98-43.01). Hyperparathyroidism was noted in three cases of chronic poisoning suffering severe neurotoxicity.

CONCLUSION

Severe lithium neurotoxicity occurs almost exclusively in the context of chronic therapeutic administration of lithium, and rarely results from acute ingestion of lithium, even in patients currently taking lithium. As such it is an iatrogenic illness, occurring in patients who have identifiable clinical risk factors: nephrogenic diabetes insipidus, older age, abnormal thyroid function and impaired renal function. Although administration of drugs which impair lithium clearance appeared to contribute minimally to chronic lithium poisoning in the absence of other factors, these drugs may well 'uncover' the predisposing risk factors and certainly should not be considered safe to use as a consequence of this study. The serious morbidity suffered by lithium toxic patients, and the cost to society due to long hospital stays, might be reduced by careful prescribing, vigilant monitoring and awareness of these factors, as they develop in otherwise stable patients. Review of existing therapeutic guidelines may be warranted.

Neurologic complications in intensive care

Neurologic complications in intensive care occur as the result of critical illness, intensive care therapies and procedures, or medical or surgical conditions; perioperatively; or because of underlying primary neurologic disease. These complications occur at greater frequency and are often unrecognized because critically ill patients are often intubated, sedated, and/or receiving neuromuscular blocking agents. Encephalopathy is the most common neurologic complication in the ICU and is usually multifactorial in origin. Sepsis is associated with the highest incidence of neurologic complications. Neurologic complications are associated with increased disability, longer hospital stay, and increased mortality. This review focuses on neurologic complications that are the result of critical illnesses and intensive care management.

A nurse-led interdisciplinary intervention program for delirium in elderly hip-fracture patients

OBJECTIVES

To develop and test the effect of a nurse-led interdisciplinary intervention program for delirium on the incidence and course (severity and duration) of delirium, cognitive functioning, functional rehabilitation, mortality, and length of stay in older hip-fracture patients.

DESIGN

Longitudinal prospective before/after design (sequential design).

SETTING

The emergency room and two traumatological units of an academic medical center located in an urban area in Belgium.

PARTICIPANTS

60 patients in an intervention cohort (81.7% females, median age = 82, interquartile range (IQR) = 13) and another 60 patients in a usual care/nonintervention cohort (80% females, median age = 80, IQR = 12).

INTERVENTION

(1) Education of nursing staff, (2) systematic cognitive screening, (3) consultative services by a delirium resource nurse, a geriatric nurse specialist, or a psychogeriatrician, and (4) use of a scheduled pain protocol.

MEASUREMENTS

All patients were monitored for signs of delirium, as measured by the Confusion Assessment Method (CAM). Severity of delirium was assessed using a variant of the CAM. Cognitive and functional status were measured by the Mini-Mental State Examination (MMSE) (including subscales of memory, linguistic ability, concentration, and psychomotor executive skills) and the Katz Index of activities of daily living (ADLs), respectively.

RESULTS

Although there was no significant effect on the incidence of delirium (23.3% in the control vs 20.0% in the intervention cohort; P =.82), duration of delirium was shorter (P =.03) and severity of delirium was less (P =.0049) in the intervention cohort. Further, clinically higher cognitive functioning was observed for the delirious patients in the intervention cohort compared with the nonintervention cohort. Additionally, a trend toward decreased length of stay postoperatively was noted for the delirious patients in the intervention cohort. Despite these positive intervention effects, no effect on ADL rehabilitation was found. Results for risk of mortality were inconclusive.

CONCLUSIONS

This study demonstrated the beneficial effects of an intervention program focusing on early recognition and treatment of delirium in older hip-fracture patients and confirms the reversibility of the syndrome in view of the delirium's duration and severity.

MDS-Med Guide. Assessing medication effects using resident assessment data

The MDS-Med Guide is a unique new clinical tool developed to integrate patient assessment data with medication monitoring in the federally mandated resident assessment process. The guide correlates medication effects with a patient's physical, functional, and psychosocial status; identifies medications that may cause or aggravate common geriatric problems; and facilitates incorporation of medication information into the patient's care plan. The information provided in the guide is applicable to all geriatric patients receiving medication therapy to treat chronic diseases and conditions and should be of benefit to geriatric nurses in all practice settings.

Delirium

Delirium is a true medical emergency that can masquerade as chronic dementia or functional psychosis and obscure the causative underlying physical or toxic disorder. In most cases, a well-focused history and thorough physical examination can unmask the delirium and reveal the medical or toxic problem. Carefully selected diagnostic testing can be required. Emergency management of the medical or toxic disorder is the same as in nondelirious patients. Control of agitated or aggressive behavior with pharmacologic or physical restraints and special support measures are required to facilitate ED care. Delirious patients whose symptoms do not totally resolve in the ED must be admitted.

Acute confusion indicators: risk factors and prevalence using MDS data

Long-term care (LTC) Minimum Data Set (MDS) data from a Midwestern state were analyzed to validate whether components of a conceptual model developed from findings in acute care identified acute confusion risk variables in LTC. The prevalence of probable acute confusion in this sample was 13.98% (n = 324). Using a cross-sectional design, both univariate and unconditional stepwise logistic regression analyses were accomplished with presence or absence of probable acute confusion as the outcome variable (N = 2,318). Variables significantly related to acute confusion by univariate analysis were included in the logistic regression analysis. Inadequate fluid intake was the first variable to enter the stepwise equation and was highly significant (OR 3.40, 95% CI 2.99-3.81, p < .0001). Other significant variables included a diagnosis of dementia or a fall in the last 30 days. Implications for nursing practice, education and research are discussed.