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

Exposure to Sedation and Analgesia Medications: Short-term Cognitive Outcomes in Pediatric Critical Care Survivors With Acquired Brain Injury

Background/Objective: Pediatric intensive care unit (PICU) survivors risk significant cognitive morbidity, particularly those with acquired brain injury (ABI) diagnoses. Studies show sedative and analgesic medication may potentiate neurologic injury, but few studies evaluate impact on survivor outcomes. This study aimed to evaluate whether exposures to analgesic and sedative medications are associated with worse neurocognitive outcome. Methods: A retrospective cohort study was conducted of 91 patients aged 8 to 18 years, undergoing clinical neurocognitive evaluation approximately 1 to 3 months after PICU discharge. Electronic health data was queried for sedative and analgesic medication exposures, including opioids, benzodiazepines, propofol, ketamine, and dexmedetomidine. Doses were converted to class equivalents, evaluated by any exposure and cumulative dose exposure per patient weight. Cognitive outcome was derived from 8 objective cognitive assessments with an emphasis on executive function skills using Principal Components Analysis. Then, linear regression was used to control for baseline cognitive function estimates to calculate a standardized residualized neurocognitive index (rNCI) z-score. Multivariable linear regression evaluated the association between rNCI and medication exposure controlling for covariates. Significance was defined as P < .05. Results: Most (n = 80; 88%) patients received 1 or more study medications. Any exposure and higher cumulative doses of benzodiazepine and ketamine were significantly associated with worse rNCI in bivariate analyses. When controlling for Medicaid, preadmission comorbid conditions, length of stay, delirium, and receipt of other medication classes, receipt of benzodiazepine was associated with significantly worse rNCI (β-coefficient = -0.48, 95% confidence interval = -0.88, -0.08). Conclusions: Exposure to benzodiazepines was independently associated with worse acute phase cognitive outcome using objective assessments focused on executive function skills when controlling for demographic and illness characteristics. Clinician decisions regarding medication regimens in the PICU may serve as a modifiable factor to improve outcomes. Additional inquiry into associations with long-term cognitive outcome and optimal medication regimens is needed.

Subcutaneous injection of lidocaine around ischemic ankle provides safe and effective foot analgesia in patients with critical limb ischemia

OBJECTIVE

It is often difficult to alleviate foot pain associated with critical limb ischemia (CLI) using common analgesics. Neuraxial block is contraindicated in anticoagulant therapy. This study was designed to determine the response to subcutaneous injection of lidocaine around the network of peripheral nerves around the ankle in patients with CLI pain on anticoagulants and antiplatelets.

METHODS

Sixteen patients with CLI pain in the foot were enrolled in this double-blind placebo-controlled crossover study. Patients were randomized to receive either 2% lidocaine or saline via catheters inserted into the subcutaneous area around the ankle. After recurrence of pain, the patients were crossed over to receive the alternative treatment. Pain was assessed with a numerical rating scale (NRS) before and 15 min after injection. Patients used a descriptive scale to grade pain control and were asked to determine the duration of analgesia in each arm of the study.

RESULTS

No serious complications including protracted bleeding occurred. Lidocaine significantly decreased the NRS on movement from 10 (6, 10) [median (range)] to 2 (0, 10) (p < .001), and the differences in the Δ change in NRS between lidocaine and placebo were significant (p = .009). Of the 16 patients, 14 patients were very satisfied after lidocaine but only one described the same after saline. The effect of lidocaine and placebo lasted 11 (0, 28) and 1 (0, 22) h, respectively.

CONCLUSION

Subcutaneous injection of lidocaine around the ischemic ankle affectively alleviated pain in patients with CLI without serious adverse effects under anticoagulant therapy.

Determinants of delirium in elderly in-patients in a general ward setting in a teaching hospital: A case control study

Background

There is a dearth of research on risk factors of delirium among elderly inpatients in nonintensive low resource settings.

Aim

To determine the risk factors of delirium in elderly inpatients in a nonintensive care unit setting.

Materials and Methods

Sixty two elderly patients with delirium (cases) and 62 patients without delirium (controls) were administered a semi-structured proforma with socio-demographic variables and putative predisposing and precipitating risk factors and the Vellore screening instrument for dementia.

Results

On univariate analysis, factors such as past cognitive impairment, history of nocturnal confusion and delirium, diminished daily living activities, severe medical illness, history of psychiatric illness, presence of dementia, infection, fever above 1000F, abnormal electrolytes abnormal RFT, leukocytes in urine, hypoxia, anticholinergics and benzodiazepines, emergency admission, use of physical restraints, bladder catheterization, more than routine investigations, intensive care unit admission, surgery, and duration of hospital stay more than 10 days were found to be significantly associated with delirium. On multivariate analysis with binary logistic regression, bladder catheterization (odds ratio [OR] = 13.85; confidence interval [CI] = 1.44-133.14), abnormal electrolytes (OR = 5.12; CI = 1.11-23.69), and hypoxia (OR = 75.52; CI = 4.64-1.134E3) were detected to be independently associated with delirium.

Conclusion

Acute modifiable rather than long-term factors were risk factors for delirium among the elderly. An awareness of modifiable risk factors has the potential of developing targeted interventions for the early mitigation of delirium.

Associations between early in-hospital medications and the development of delirium in patients with stroke

OBJECTIVES

Patients hospitalized with stroke develop delirium at higher rates than general hospitalized patients. While several medications are associated with existing delirium, it is unknown whether early medication exposures are associated with subsequent delirium in patients with stroke. Additionally, it is unknown whether delirium identification is associated with changes in the prescription of these medications.

MATERIALS AND METHODS

We conducted a retrospective cohort study of patients admitted to a comprehensive stroke center, who were assessed for delirium by trained nursing staff during clinical care. We analyzed exposures to multiple medication classes in the first 48 h of admission, and compared them between patients who developed delirium >48 hours after admission and those who never developed delirium. Statistical analysis was performed using univariate testing. Multivariable logistic regression was used further to evaluate the significance of univariately significant medications, while controlling for clinical confounders.

RESULTS

1671 unique patients were included in the cohort, of whom 464 (27.8%) developed delirium >48 hours after admission. Delirium was associated with prior exposure to antipsychotics, sedatives, opiates, and antimicrobials. Antipsychotics, sedatives, and antimicrobials remained significantly associated with delirium even after accounting for several clinical covariates. Usage of these medications decreased in the 48 hours following delirium identification, except for atypical antipsychotics, whose use increased. Other medication classes such as steroids, benzodiazepines, and sleep aids were not initially associated with subsequent delirium, but prescription patterns still changed after delirium identification.

CONCLUSIONS

Early exposure to multiple medication classes is associated with the subsequent development of delirium in patients with stroke. Additionally, prescription patterns changed following delirium identification, suggesting that some of the associated medication classes may represent modifiable targets for future delirium prevention strategies, although future study is needed.

Delirium in older patients given propofol or sevoflurane anaesthesia for major cancer surgery: a multicentre randomised trial

BACKGROUND

Delirium is a common and disturbing postoperative complication that might be ameliorated by propofol-based anaesthesia. We therefore tested the primary hypothesis that there is less delirium after propofol-based than after sevoflurane-based anaesthesia within 7 days of major cancer surgery.

METHODS

This multicentre randomised trial was conducted in 14 tertiary care hospitals in China. Patients aged 65-90 yr undergoing major cancer surgery were randomised to either propofol-based anaesthesia or to sevoflurane-based anaesthesia. The primary endpoint was the incidence of delirium within 7 postoperative days.

RESULTS

A total of 1228 subjects were enrolled and randomised, with 1195 subjects included in the modified intention-to-treat analysis (mean age 71 yr; 422 [35%] women); one subject died before delirium assessment. Delirium occurred in 8.4% (50/597) of subjects given propofol-based anaesthesia vs 12.4% (74/597) of subjects given sevoflurane-based anaesthesia (relative risk 0.68 [95% confidence interval {CI}: 0.48-0.95]; P=0.023; adjusted relative risk 0.59 [95% CI: 0.39-0.90]; P=0.014). Delirium reduction mainly occurred on the first day after surgery, with a prevalence of 5.4% (32/597) with propofol anaesthesia vs 10.7% (64/597) with sevoflurane anaesthesia (relative risk 0.50 [95% CI: 0.33-0.75]; P=0.001). Secondary endpoints, including ICU admission, postoperative duration of hospitalisation, major complications within 30 days, cognitive function at 30 days and 3 yr, and safety outcomes, did not differ significantly between groups.

CONCLUSIONS

Delirium was a third less common after propofol than sevoflurane anaesthesia in older patients having major cancer surgery. Clinicians might therefore reasonably select propofol-based anaesthesia in patients at high risk of postoperative delirium.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR-IPR-15006209) and ClinicalTrials.gov (NCT02662257).

Delirium-associated medication in people at risk: A systematic update review, meta-analyses, and GRADE-profiles

BACKGROUND

Drug-associated delirium is a common but potentially preventable neuropsychiatric syndrome associated with detrimental outcomes. Empirical evidence for delirium-associated medication is uncertain due to a lack of high-quality studies. We aimed to further investigate the body of evidence for drugs suspected to trigger delirium.

METHODS

A systematic update review and meta-analyses of prospective studies presenting drug associations with incident delirium in adult study populations was conducted. Two authors independently searched MEDLINE, PsycINFO, Embase, and Google Scholar dated from October 1, 2009 to June 23, 2020, after screening a previous review published in 2011. The most reliable results on drug-delirium associations were pooled in meta-analyses using the random-effects model. Quality of evidence was assessed using the GRADE-approach. This study is preregistered with OSF (DOI https://doi.org.10.17605/OSF.IO/4PUHY).

RESULTS

The 31 eligible studies, presenting results for 24 medication classes were identified. Meta-analyses and GRADE level of evidence ratings show no increased delirium risk for Haloperidol (OR: 0.96, 95% CI 0.72-1.28; high-quality evidence), Olanzapine (OR: 0.25, 95% CI 0.15-0.40), Ketamine (OR: 0.72, 95% CI 0.35-1.46) or corticosteroids (OR: 0.69, 95% CI 0.32-1.50; moderate quality evidence, respectively). Low-level evidence suggests a three-fold increased risk for anticholinergics (OR: 3.11, 95% CI 1.04-9.26). Opioids, benzodiazepines, H₁ -antihistamines, and antidepressants did not reach reliable evidence levels in our analyses.

CONCLUSION

We investigated the retrievable body of evidence for delirium-associated medication. The results of this systematic review were then interpreted in conjunction with other evidence-based works and guidelines providing conclusions for clinical decision-making.

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.

The detection of delirium in admitted oncology patients: a scoping review

Aim

To understand the validation of delirium detection tools in medical oncology, as well as identify data on incidence, prevalence and reversibility in this setting.

Findings

Of twelve studies, only four used case ascertainment methods following published recommendations, six studies had a low risk of bias.

Message

In delirium tool validation studies in the oncology setting, choice of appropriate gold standard for case ascertainment is a critical factor. New tools and new validations are not recommended, rather the critical application of existing tools depending on appropriate validation and clinical practicality for the setting.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-021-00586-1.

Purpose

Delirium leads to poor outcomes for patients and careers and has negative impacts on staff and service provision. Cancer rates in elderly populations are increasing and frequently, cancer diagnoses are a co-morbidity in the context of frailty. Data relating to the epidemiology of delirium in hospitalised cancer patients are limited. With the overarching purpose of improving delirium detection and reducing the morbidity and mortality of delirium in cancer patients, we reviewed the epidemiological data and approach to delirium detection in hospitalised, adult oncology patients.

Methods

MEDLINE, EMBASE, CINAHL, PsycINFO, and SCOPUS databases were searched from January 1996 to August 2017. Key concepts were delirium, cancer, inpatient oncology and delirium screening/detection.

Results

Of 896 unique studies identified; 91 met full-text review criteria. Of 12 eligible studies, four applied recommended case ascertainment methods to all patients, three used delirium screening tools alone or with case ascertainment tools sub-optimally applied, four used tools not recommended for delirium screening or case ascertainment, one used the Confusion Assessment Method with insufficient information to determine if it met case ascertainment status. Two studies presented delirium incidence rates: 7.8%, and 17% respectively. Prevalence rates ranged from 18–33% for general medical or oncology wards; 42–58% for Acute Palliative Care Units (APCU); and for older cancer patients: 22% and 57%. Three studies reported reversibility; 26% and 49% respectively (APCUs) and 30% (older patients with cancer). Six studies had a low risk of bias according to QUADAS-2 criteria; all studies in the APCU setting were rated at higher risk of bias. Tool selection, study flow and recruitment bias reduced study quality.

Conclusion

The knowledge base for improved interventions and clinical care for adults with cancer and delirium is limited by the low number of studies. A clear distinction between screening tools and diagnostic tools is required to provide an improved understanding of the rates of delirium and its reversibility in this population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-021-00586-1.

Cognitive Dysfunction After Analgesia and Sedation: Out of the Operating Room and Into the Pediatric Intensive Care Unit

In the midst of concerns for potential neurodevelopmental effects after surgical anesthesia, there is a growing awareness that children who require sedation during critical illness are susceptible to neurologic dysfunctions collectively termed pediatric post-intensive care syndrome, or PICS-p. In contrast to healthy children undergoing elective surgery, critically ill children are subject to inordinate neurologic stress or injury and need to be considered separately. Despite recognition of PICS-p, inconsistency in techniques and timing of post-discharge assessments continues to be a significant barrier to understanding the specific role of sedation in later cognitive dysfunction. Nonetheless, available pediatric studies that account for analgesia and sedation consistently identify sedative and opioid analgesic exposures as risk factors for both in-hospital delirium and post-discharge neurologic sequelae. Clinical observations are supported by animal models showing neuroinflammation, increased neuronal death, dysmyelination, and altered synaptic plasticity and neurotransmission. Additionally, intensive care sedation also contributes to sleep disruption, an important and overlooked variable during acute illness and post-discharge recovery. Because analgesia and sedation are potentially modifiable, understanding the underlying mechanisms could transform sedation strategies to improve outcomes. To move the needle on this, prospective clinical studies would benefit from cohesion with regard to datasets and core outcome assessments, including sleep quality. Analyses should also account for the wide range of diagnoses, heterogeneity of this population, and the dynamic nature of neurodevelopment in age cohorts. Much of the related preclinical evidence has been studied in comparatively brief anesthetic exposures in healthy animals during infancy and is not generalizable to critically ill children. Thus, complementary animal models that more accurately "reverse translate" critical illness paradigms and the effect of analgesia and sedation on neuropathology and functional outcomes are needed. This review explores the interactive role of sedatives and the neurologic vulnerability of critically ill children as it pertains to survivorship and functional outcomes, which is the next frontier in pediatric intensive care.

Delirium in Older Patients after Combined Epidural-General Anesthesia or General Anesthesia for Major Surgery: A Randomized Trial

BACKGROUND

Delirium is a common and serious postoperative complication, especially in the elderly. Epidural anesthesia may reduce delirium by improving analgesia, reducing opioid consumption, and blunting stress response to surgery. This trial therefore tested the hypothesis that combined epidural-general anesthesia reduces the incidence of postoperative delirium in elderly patients recovering from major noncardiac surgery.

METHODS

Patients aged 60 to 90 yr scheduled for major noncardiac thoracic or abdominal surgeries expected to last 2 h or more were enrolled. Participants were randomized 1:1 to either combined epidural-general anesthesia with postoperative epidural analgesia or general anesthesia with postoperative intravenous analgesia. The primary outcome was the incidence of delirium, which was assessed with the Confusion Assessment Method for the Intensive Care Unit twice daily during the initial 7 postoperative days.

RESULTS

Between November 2011 and May 2015, 1,802 patients were randomized to combined epidural-general anesthesia (n = 901) or general anesthesia alone (n = 901). Among these, 1,720 patients (mean age, 70 yr; 35% women) completed the study and were included in the intention-to-treat analysis. Delirium was significantly less common in the combined epidural-general anesthesia group (15 [1.8%] of 857 patients) than in the general anesthesia group (43 [5.0%] of 863 patients; relative risk, 0.351; 95% CI, 0.197 to 0.627; P < 0.001; number needed to treat 31). Intraoperative hypotension (systolic blood pressure less than 80 mmHg) was more common in patients assigned to epidural anesthesia (421 [49%] vs. 288 [33%]; relative risk, 1.47, 95% CI, 1.31 to 1.65; P < 0.001), and more epidural patients were given vasopressors (495 [58%] vs. 387 [45%]; relative risk, 1.29; 95% CI, 1.17 to 1.41; P < 0.001).

CONCLUSIONS

Older patients randomized to combined epidural-general anesthesia for major thoracic and abdominal surgeries had one third as much delirium but 50% more hypotension. Clinicians should consider combining epidural and general anesthesia in patients at risk of postoperative delirium, and avoiding the combination in patients at risk of hypotension.

EDITOR’S PERSPECTIVE

Evaluation of the course and treatment of Alcohol Withdrawal Syndrome with the Clinical Institute Withdrawal Assessment for Alcohol - Revised: A systematic review-based meta-analysis

BACKGROUND

Although the Clinical Institute Withdrawal Assessment for Alcohol - Revised (CIWA-Ar) is a gold standard tool for the clinical evaluation of alcohol withdrawal syndrome (AWS), a systematic analysis using the total scores of the CIWA-Ar as a means of an objective follow-up of the course and treatment of AWS is missing. The aims of the present study were to systematically evaluate scientific data using the CIWA-Ar, to reveal whether the aggregated CIWA-Ar total scores follow the course of AWS and to compare benzodiazepine (BZD) and non-benzodiazepine (nBZD) therapies in AWS.

METHODS

1054 findings were identified with the keyword "ciwa" from four databases (PubMed, ScienceDirect, Web of Science, Cochrane Registry). Articles using CIWA-Ar in patients treated with AWS were incorporated and two measurement intervals (cumulative mean data of day 1-3 and day 4-9) of the CIWA-Ar total scores were compared. Subgroup analysis based on pharmacotherapy regimen was conducted to compare the effectiveness of BZD and nBZD treatments.

RESULTS

The random effects analysis of 423 patients showed decreased CIWA-Ar scores between the two measurement intervals (BZD: d = -1.361; CI: -1.829 < δ < -0.893; nBZD: d = -0.858; CI: -1.073 < δ < -0.643). Sampling variances were calculated for the BZD (v₁ = 0.215) and the nBZD (v₂ = 0.106) groups, which indicated no significant group difference (z = -1.532).

CONCLUSIONS

Our findings support that the CIWA-Ar follows the course of AWS. Furthermore, nBZD therapy has a similar effectiveness compared to BZD treatment based on the CIWA-Ar total scores.

Depression in Cancer Care

Depression is common among cancer patients and their families, and may lead to substantial clinical consequences. Clinicians should routinely screen cancer patients for comorbid depression and should provide appropriate care at both primary and specialized care levels. Good quality care is beneficial not only for cancer patients themselves but also for their family members. It includes good communication between patients and health providers, and addressing of unmet needs of cancer patients. Specialized care comprises pharmacotherapy and psychotherapy. The advancement of psychotherapy for cancer patients parallels the advancement of general psychotherapy. Among the many types of psychotherapies, mindfulness-based interventions have been attracting growing attention. Some relevant studies that have been conducted in Keio University Hospital are described herein.

Preventive Effect of Suvorexant for Postoperative Delirium after Coronary Artery Bypass Grafting

OBJECTIVE

Suvorexant is an orexin receptor antagonist and is effective in inducing sleep. We hypothesized that Suvorexant would reduce the incidence of postoperative delirium (POD) after coronary artery bypass grafting (CABG).

METHODS

We reviewed 88 patients (12 women, mean age: 69.3 ± 2.5 years) who were undergone CABG alone. Patients were divided into two groups; patients received Suvorexant (S group, n = 36), patients not received Suvorexant (N group, n = 52), and the following data were analyzed and compared between two groups.

RESULTS

Intensive Care Unit Delirium Screening Checklist Score was significantly lower in S group compared with N group (N:S = 2.0 ± 1.7:0.8 ± 1.0, p = 0.0003). Although POD was present in 11 of 52 patients (21.2%) in N group, one patient (2.8%) developed in S group (p = 0.008). In S group, both intensive care unit stay (N:S = median 6:5 days, p = 0.001) and hospital stay (N:S = median 23:20 days, p = 0.035) were significantly shorter than in N group.

CONCLUSIONS

Suvorexant might reduce incidence of POD in patients undergone CABG.

Acute Brain Failure: Pathophysiology, Diagnosis, Management, and Sequelae of Delirium

Delirium is the most common psychiatric syndrome found in the general hospital setting, with an incidence as high as 87% in the acute care setting. Delirium is a neurobehavioral syndrome caused by the transient disruption of normal neuronal activity secondary to systemic disturbances. The development of delirium is associated with increased morbidity, mortality, cost of care, hospital-acquired complications, placement in specialized intermediate and long-term care facilities, slower rate of recovery, poor functional and cognitive recovery, decreased quality of life, and prolonged hospital stays. This article discusses the epidemiology, known etiological factors, presentation and characteristics, prevention, management, and impact of delirium.

Central Nervous System-Acting Medicines and Risk of Hospital Admission for Confusion, Delirium, or Dementia

BACKGROUND

Most studies assessing the effect of central nervous system (CNS)-acting medicines on cognitive disturbances have focused on the use of individual medicines. The impact on cognitive function when another CNS-acting medicine is added to a patient's treatment regimen is not well known.

OBJECTIVE

To determine risk of hospitalization for confusion, delirium, or dementia in older people associated with increasing numbers of CNS-acting medicines taken concurrently, as well as the number of standard doses taken each day (measured as defined daily doses).

DESIGN

Retrospective cohort study, from July 2011 to June 2012, using health claims data.

SETTING

Australian veteran population.

PARTICIPANTS

A total of 74,321 community-dwelling individuals aged 65 years and over, who were dispensed at least 1 CNS-acting medicine in the year before study entry. Patients with prior hospitalization for confusion or delirium, and those with dementia or receiving palliative care, were excluded.

MAIN OUTCOME MEASURE

Hospitalization for confusion, delirium, or dementia.

RESULTS

Over the 1-year study period, 401 participants were hospitalized with confusion, delirium, or dementia. Adjusted analyses showed the risk of hospitalization was 2.4 times greater with the use of 2 CNS-acting medicines compared with no use [incident rate ratio (IRR) 2.39, 95% confidence interval (CI) 1.79-3.19, P < .001], and more than 19 times greater when 5 or more CNS-acting medicines were taken concurrently (IRR 19.35, 95% CI 11.10-33.72, P < .001). Similarly, the risk of hospitalization was significantly increased among patients taking between 1.0 and 1.9 standard doses per day (IRR 2.64, 95% CI 1.99-3.50, P < .001) and between 2.0 and 2.9 standard doses per day (IRR 3.43, 95% CI 2.07-5.69, P < .001) compared with no use.

CONCLUSIONS

Use of multiple CNS-acting medicines or higher doses is associated with an increased risk of hospitalization for confusion, delirium, or dementia. Health care professionals need to be alert to the contribution of CNS-acting medicines among patients presenting with confusion or delirium and consider strategies to reduce treatment burden where possible.

Incidence of Delirium Among Patients Having Cancer Injected With Different Opioids for the First Time

Background:

Despite the risk of drug-induced delirium, it is difficult to avoid the use of opioids in palliative care. However, no previous study has carefully investigated how the development of delirium varies among patients injected with different opioids for the first time.

Objectives:

To reveal the difference in the incidence of delirium between different opioids.

Design:

The incidence of delirium was compared among 114 patients who had started morphine, oxycodone, or fentanyl injection at Shizuoka Cancer Center between June 2012 and September 2014.

Results:

The incidence of delirium was 28.9% in the morphine group (n = 38), 19.5% in the oxycodone group (n = 41), and 8.6% in the fentanyl group (n = 35). There was a significant difference between the morphine and fentanyl groups (Fisher’s exact test, P = 0.04) but not between the morphine and oxycodone groups (P = 0.43) nor between the oxycodone and fentanyl groups (P = 0.21).

Conclusions:

The incidence of delirium after the commencement of fentanyl injection was significantly lower, suggesting that fentanyl is a useful opioid injection drug from the perspective of delirium risk.

Effect of melatonin on duration of delirium in organophosphorus compound poisoning patients: A double-blind randomised placebo controlled trial

Background and Aims:

Organophosphate compound poisoning (OPCP) is associated with high incidence of delirium. Melatonin has been tried in the treatment of delirium and has shown a beneficial effect in OPCP. This study was conducted to know the effect of melatonin on duration of delirium and recovery profile in OPCP patients.

Methods:

Double-blind randomised placebo control trial in which 56 patients of OPCP confirmed by history and syndrome of OPCP with low plasma pseudocholinesterase, aged >18 years and weighing between 50 and 100 kg, and Acute Physiology and Chronic Health Evaluation II score of <20 were studied. Group M (n = 26) received tablet melatonin 3 mg and Group C (n = 30) received placebo tablet at 9 PM, every night throughout the Intensive Care Unit (ICU) stay. Delirium was assessed using the Confusion Assessment Method for ICU, thrice a day. Sedation was provided with injection midazolam, fentanyl and lorazepam. Duration of mechanical ventilation, vital parameters, ICU stay, sedative and atropine requirement, were recorded.

Results:

The time taken to be delirium free was significantly lower in Group M (6 ± 2.92 days) compared to Group C (9.05 ± 2.75 days) (P = 0.001) and prevalence of delirium was significantly decreased in Group M compared to Group C from day 3 onwards. The requirement of midazolam (Group M - 2.98 ± 4.99 mg/day, Group C - 9.68 ± 9.17 mg/day, P < 0.001) and fentanyl (Group M - 94.09 ± 170.05 μg/day, Group C - 189.33 ± 156.38 μg/day, P = 0.03) decreased significantly in Group M. There was no significant difference in the average atropine consumption (P = 0.27), duration of mechanical ventilation (P = 0.26), ICU stay (P = 0.21) and the number of patients requiring mechanical ventilation (P = 0.50).

Conclusion:

Orally given melatonin in organophosphate compound poisoning patients reduces the duration of delirium and the requirement of sedation and analgesia.

Delirium as a complication of the surgical intensive care

BACKGROUND

The aim of this study was to examine the impact of somatic illnesses, electrolyte imbalance, red blood cell count, hypotension, and antipsychotic and opioid treatment on the duration of delirium in Central Intensive Care Unit for Surgery.

PATIENTS AND METHODS

Patients who were admitted to the Department of Central Intensive Care Unit for Surgery in the University Hospital Olomouc from February 2004 to November 2008 were evaluated using Riker sedation-agitation scale. Their blood pressure, heart rate, respiratory rate, and peripheral blood oxygen saturation were measured continually, and body temperature was monitored once in an hour. The laboratory blood tests including sodium, potassium, chlorides, phosphorus, urea and creatinine, hemoglobin, hematocrit, red and white blood cell count, and C-reactive protein, albumin levels and laboratory markers of renal and liver dysfunction were done every day. All measurements were made at least for ten consecutive days or longer until the delirium resolved.

RESULTS

The sample consisted of 140 consecutive delirious patients with a mean age of 68.21±12.07 years. Delirium was diagnosed in 140 of 5,642 patients (2.48%) admitted in CICUS in the last 5 years. The median duration of delirium was 48 hours with a range of 12-240 hours. Statistical analysis showed that hyperactive subtype of delirium and treatment with antipsychotics were associated with prolonged delirium duration (hyperactive 76.15±40.53 hours, hypoactive 54.46±28.44 hours, mixed 61.22±37.86 hours; Kruskal-Wallis test: 8.022; P<0.05). The duration of delirium was significantly correlated also with blood potassium levels (Pearson's r=0.2189, P<0.05), hypotension (hypotension 40.41±30.23 hours versus normotension 70.47±54.98 hours; Mann-Whitney U=1,512; P<0.05), administration of antipsychotics compared to other drugs (antipsychotics 72.83±40.6, benzodiazepines 42.00±20.78, others drugs, mostly piracetam 46.96±18.42 hours; Kruskal-Wallis test: 17.39, P<0.0005), and history of alcohol abuse (with a history of abuse 73.63±45.20 hours, without a history of abuse 59.54±30.61 hours; Mann-Whitney U=1,840; P<0.05). One patient had suffered from complicated postoperative hypostatic pneumonia and died due to respiratory failure (patient with hypoactive subtype). According to the backward stepwise multiple regression, the best significant predictors of duration of the delirium were the hypotension, type of psychopharmacs, type of delirium, the daily dose of opioids, a combination of psychopharmacs, history of alcohol abuse, plasma level of potassium, anemia, hyperpyrexia, and plasma level of albumin, reaching statistical significance (analysis of variance: F=5.205; df=24; P<0.005; adjusted r²=0.637).

CONCLUSION

The hyperactive type of delirium, hypotension, usage of antipsychotics, the higher daily dose of opioids, a combination of psychopharmacs, history of alcohol abuse, low blood levels of potassium, anemia, hyperpyrexia, and hypoalbuminemia in the CICUS were associated with longer duration of delirium.

Effect of melatonin on incidence of delirium among patients with hip fracture: a multicentre, double-blind randomized controlled trial

BACKGROUND

Disturbance of the sleep-wake cycle is a characteristic of delirium. In addition, changes in melatonin rhythm influence the circadian rhythm and are associated with delirium. We compared the effect of melatonin and placebo on the incidence and duration of delirium.

METHODS

We performed this multicentre, double-blind, randomized controlled trial between November 2008 and May 2012 in 1 academic and 2 nonacademic hospitals. Patients aged 65 years or older who were scheduled for acute hip surgery were eligible for inclusion. Patients received melatonin 3 mg or placebo in the evening for 5 consecutive days, starting within 24 hours after admission. The primary outcome was incidence of delirium within 8 days of admission. We also monitored the duration of delirium.

RESULTS

A total of 452 patients were randomly assigned to the 2 study groups. We subsequently excluded 74 patients for whom the primary end point could not be measured or who had delirium before the second day of the study. After these postrandomization exclusions, data for 378 patients were included in the main analysis. The overall mean age was 84 years, 238 (63.0%) of the patients lived at home before admission, and 210 (55.6%) had cognitive impairment. We observed no effect of melatonin on the incidence of delirium: 55/186 (29.6%) in the melatonin group v. 49/192 (25.5%) in the placebo group; difference 4.1 (95% confidence interval -0.05 to 13.1) percentage points. There were no between-group differences in mortality or in cognitive or functional outcomes at 3-month follow-up.

INTERPRETATION

In this older population with hip fracture, treatment with melatonin did not reduce the incidence of delirium.

TRIAL REGISTRATION

Netherlands Trial Registry, NTR1576: MAPLE (Melatonin Against PLacebo in Elderly patients) study; www.trialregister.nl/trialreg/admin/rctview.asp?TC=1576.

Post-operative delirium in elderly patients

Delirium is a common, but an often underdiagnosed complication in the elderly following major surgery. Recognising delirium in early stages and diagnosing the condition based on established criteria can improve the outcome and management. Managing delirium with environmental, supportive and pharmacological interventions will possibly reduce the incidence and side-effects associated with post-operative delirium. The purpose of this article is to provide an over view of the current knowledge about the disease, diagnosis, pathogenesis, preventive strategies, and treatment of post-operative delirium.

Antipsychotic Prescribing Patterns, and the Factors and Outcomes Associated with Their Use, among Patients Requiring Prolonged Mechanical Ventilation in the Long-Term Acute Care Hospital Setting

BACKGROUND:

Administration of scheduled antipsychotic therapy to mechanically ventilated patients to prevent or treat delirium is common, despite the lack of evidence to support its use. Among long-term acute care hospital (LTACH) patients requiring prolonged mechanical ventilation (PMV), the frequency of scheduled antipsychotic therapy use, and the factors and outcomes associated with it, have not been described.

OBJECTIVE:

To identify scheduled antipsychotic therapy prescribing practices, and the factors and outcomes associated with the use of antipsychotics, among LTACH patients requiring PMV.

METHODS:

Consecutive patients without major psychiatric disorders or dementia who were admitted to an LTACH for PMV over 1 year were categorized as those receiving scheduled antipsychotic therapy (≥24 hours of use) and those not receiving scheduled antipsychotic therapy. Presence of delirium, use of psychiatric evaluation, nonscheduled antipsychotic therapy, and scheduled antipsychotic therapy—related adverse effects were extracted and compared between the 2 groups and when significant (p ≤ 0.05), were entered into a regression analysis using generalized estimating equation techniques.

RESULTS:

Among 80 patients included, 39% (31) received scheduled antipsychotic therapy and 61% (49) did not. Baseline characteristics, including age, sex, illness severity, and medical history, were similar between the 2 groups. Scheduled antipsychotic therapy was administered on 52% of LTACH days for a median (interquartile range [IQR]) of 25 (6–38) days and, in the antipsychotic group, was initiated at an outside hospital (45%) or on day 2 (1–6; median [IQR]) of the LTACH stay (55%). Quetiapine was the most frequently administered scheduled antipsychotic (77%; median dose 50 [37–72] mg/day). Use of scheduled antipsychotic therapy was associated with a greater incidence of psychiatric evaluation (OR 5.7; p = 0.01), delirium (OR 2.4; p = 0.05), as-needed antipsychotic use (OR 4.1; p = 0.005) and 1:1 sitter use (OR 7.3; p = 0.001), but not benzodiazepine use (p = 0.19).

CONCLUSIONS:

Among LTACH patients requiring PMV, scheduled antipsychotic therapy is used frequently and is associated with a greater incidence of psychiatric evaluation, delirium, as-needed psychotic use, and sitter use. Although scheduled antipsychotic therapy—related adverse effects are uncommon, these effects are infrequently monitored.

Delirium in critically ill patients: epidemiology, pathophysiology, diagnosis and management

Delirium is commonly observed in critically ill patients and is associated with negative outcomes. The pathophysiology of delirium is not completely understood. However, alterations to neurotransmitters, especially acetylcholine and dopamine, inflammatory pathways and an aberrant stress response are proposed mechanisms leading to intensive care unit (ICU) delirium. Detection of delirium using a validated delirium assessment tool makes early treatment possible, which may improve prognosis. Patients at high risk of delirium, especially those with cognitive decline and advanced age, should be identified in the first 24 hours of admission to the ICU. Whether these high-risk patients benefit from haloperidol prophylaxis deserves further study. The effectiveness of a multicomponent, non-pharmacological approach is shown in non-ICU patients, which provides proof of concept for use in the ICU. The few studies on this approach in ICU patients suggest that the burden of ICU delirium may be reduced by early mobility, increased daylight exposure and the use of earplugs. In addition, the combined use of sedation, ventilation, delirium and physical therapy protocols can reduce the frequency and severity of adverse outcomes and should become part of routine practice in the ICU, as should avoidance of deliriogenic medication such as anticholinergic drugs and benzodiazepines. Once delirium develops, symptomatic treatment with antipsychotics is recommended, with haloperidol being the drug of first choice. However, there is limited evidence on the safety and effectiveness of antipsychotics in ICU delirium.

Delirium: an emerging frontier in the management of critically ill children

Delirium is a syndrome of acute brain dysfunction that commonly occurs in critically ill adults and most certainly is prevalent in critically ill children all over the world. The dearth of information about the incidence, prevalence, and severity of pediatric delirium stems from the simple fact that there have not been well-validated instruments for routine delirium diagnosis at the bedside. This article reviewed the emerging solutions to this problem, including description of a new pediatric tool called the pCAM-ICU. In adults, delirium is responsible for significant increases in both morbidity and mortality in critically ill patients. The advent of new tools for use in critically ill children will allow the epidemiology of this form of acute brain dysfunction to be studied adequately, will allow clinical management algorithms to be developed and implemented following testing, and will present the necessary incorporation of delirium as an outcome measure for future clinical trials in pediatric critical care medicine.

Delirium: a review

Delirium affects a diverse patient population, may present with highly variable clinical features, is a source of distress for patients and their caregivers, prolongs hospital stays and may herald a poor prognosis. Many cases of delirium are reversible and therefore a full history, physical examination and investigations should be performed. Ahigh degree of suspicion is required for detecting delirium and thorough investigations are necessary in order to determine the underlying etiology and to maximize the potential for reversibility. The following review outlines important aspects of a clinical approach to delirium, the differential diagnosis of delirium, investigation of a patient presenting with delirium, management of delirium, the pathophysiology of delirium and the prognosis accompanying delirium.

Evaluation of dexmedetomidine versus propofol-based sedation therapy in mechanically ventilated cardiac surgery patients at a tertiary academic medical center

Management of pain and sedation therapy is a vital component of optimizing patient outcomes; however, the ideal pharmacotherapy regimen has not been identified in the postoperative cardiac surgery population. We sought to evaluate efficacy and safety outcomes between postoperative mechanically ventilated cardiac surgery patients receiving dexmedetomidine versus propofol therapy upon arrival to the intensive care unit (ICU). We conducted a single center, descriptive study of clinical practice at a 20-bed cardiac surgery ICU in a tertiary academic medical center. Adult mechanically ventilated postcardiac surgery patients who received either dexmedetomidine or propofol for sedation therapy upon admission to the ICU between October 20, 2006 and December 15, 2006 were evaluated. A pharmacy database was used to identify patients receiving dexmedetomidine or propofol therapy for perioperative sedation during cardiac surgery. Patients were matched according to surgical procedure type. Fifty-six patients who received either dexmedetomidine (n = 28) or propofol (n = 28) were included in the analysis. No differences in the ICU length of stay (58.67 ± 32.61 vs. 61 ± 33.1 hours; P = 0.79) and duration of mechanical ventilation (16.21 ± 6.05 vs. 13.97 ± 4.62 hours; P = 0.13) were seen between the propofol and dexmedetomidine groups, respectively. Hypotension (17 [61%] vs. 9 [32%]; P = 0.04), morphine use (11 [39.3%] vs. 1 [3.6%]; P = 0.002), and nonsteroidal anti-inflammatory use (7 [25%] vs. 1 [3.6%]; P = 0.05) occurred more during dexmedetomidine therapy versus propofol. Dexmedetomidine therapy resulted in a higher incidence of hypotension and analgesic consumption compared with propofol-based sedation therapy. Further evaluation is needed to assess differences in clinical outcomes of propofol and dexmedetomidine-based therapy in mechanically ventilated cardiac surgery patients.

[Delirium in the intensive care unit]

In recent years delirium in the intensive care unit (ICU) has internationally become a matter of rising concern for intensive care physicians. Due to the design of highly sophisticated ventilators the practice of deep sedation is nowadays mostly obsolete. To assess a ventilated ICU patient for delirium easy to handle bedside tests have been developed which permit a psychiatric scoring. The significance of ICU delirium is equivalent to organ failure and has been proven to be an independent prognostic factor for mortality and length of ICU and hospital stay. The pathophysiology and risk factors of ICU delirium are still insufficiently understood in detail. A certain constellation of pre-existing patient-related conditions, the current diagnosis and surgical procedure and administered medication entail a higher risk for the occurrence of ICU delirium. A favored hypothesis is that an imbalance of the neurotransmitters acetylcholine and dopamine serotonin results in an unpredictable neurotransmission. Currently, the administration of neuroleptics, enforced physiotherapy, re-orientation measures and appropriate pain treatment are the basis of the therapeutic approach.

Review of topiramate for the treatment of epilepsy in elderly patients

Individuals over 65 years of age experience the new onset of seizures at a prevalence rate of roughly twice that of younger adults. Differences in physiology, need of concomitant medications, and liability for cognitive deficits in this population, make the choice of anticonvulsant drugs especially important. This paper reviews topiramate (TPM), a treatment for many types of seizures, with the above risks in mind. In particular, we discuss efficacy and pharmacokinetics with emphasis on the older patient, and adverse events in both the younger and older adult. With most studies of TPM-induced cognitive deficits having been performed in younger adults and volunteers, we discuss the implications for the older adult. Even in studies of younger individuals, up to 50% discontinue TPM because of intolerable cognitive deficits. Most studies find specific declines in working memory and verbal fluency. In conclusion, we give recommendations for use of this antiepileptic drug in this population.

Strategies for promoting early activity in critically ill mechanically ventilated patients

Prolonged immobilization plays a significant role in neuromuscular abnormalities and complicates the clinical course of a majority of critically ill patients. Immobilization in critically ill patients is associated with significant morbidity and impaired physical function. Overuse of sedation, sleep deprivation, immobility, and the development of delirium are all intensive care unit (ICU) factors that may negatively impact patient outcomes. Ambulation of critically ill patients is difficult with risk for adverse events. However, with a dedicated and trained team and culture change, early ICU mobility can be a feasible and safe process. Early mobility has potential as a therapy to prevent or treat the neuromuscular complications of critical illness. ICU culture can be transformed in a way that leads to improved and more reliable treatments and care, including early activity and mobility.

Delirium: an emerging frontier in the management of critically ill children

The objectives of this article are (1) to introduce pediatric delirium and provide understanding of acute brain dysfunction with its classification and clinical presentations (2) to understand how delirium is diagnosed and discuss current modes of delirium diagnosis in the critically ill adult population and translation to pediatrics (3) to understand the prevalence and prognostic significance of delirium in the adult and pediatric critically ill population (4) to discuss the pathophysiology of delirium as currently understood, and (5) to provide general management guidelines for delirium.

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.

Pathoetiological model of delirium: a comprehensive understanding of the neurobiology of delirium and an evidence-based approach to prevention and treatment

Delirium is the most common complication found in the general hospital setting. Yet, we know relatively little about its actual pathophysiology. This article contains a summary of what we know to date and how different proposed intrinsic and external factors may work together or by themselves to elicit the cascade of neurochemical events that leads to the development delirium. Given how devastating delirium can be, it is imperative that we better understand the causes and underlying pathophysiology. Elaborating a pathoetiology-based cohesive model to better grasp the basic mechanisms that mediate this syndrome will serve clinicians well in aspiring to find ways to correct these cascades, instituting rational treatment modalities, and developing effective preventive techniques.

Delirium in the acute care setting: characteristics, diagnosis and treatment

Delirium is a neurobehavioral syndrome caused by the transient disruption of normal neuronal activity secondary to systemic disturbances. It is also the most common psychiatric syndrome found in the general hospital setting, its prevalence surpassing better known psychiatric disorders. This article reviews the published literature on delirium and addresses the epidemiology, known etiologic factors, presentation and characteristics of delirium, while emphasizing what is known about treatment strategies and prevention. Given increasing evidence that delirium is not always reversible and the many sequelae associated with its development, physicians must do everything possible to prevent its occurrence or shorten its duration, by recognizing its symptoms early, correcting underlying contributing causes, and using treatment strategies proven to help recover functional status.

Delirium and its treatment

Delirium occurs at rates ranging from 10% to 30% of all hospital admissions. It is a negative prognostic indicator, often leading to longer hospital stays and higher mortality. The aetiology of delirium is multifactorial and many causes have been suggested. The stress-diathesis model, which posits an interaction between the underlying vulnerability and the nature of the precipitating factor, is useful in understanding delirium. Preventing delirium is the most effective strategy for reducing its frequency and complications. Environmental strategies are valuable but are often underutilized, while remedial treatment is usually aimed at specific symptoms of delirium. Antipsychotics are the mainstay of pharmacological treatment and have been shown to be effective in treating symptoms of both hyperactive and hypoactive delirium, as well as generally improving cognition. Haloperidol is considered to be first-line treatment as it can be administered via many routes, has fewer active metabolites, limited anticholinergic effects and has a lower propensity for sedative or hypotensive effects compared with many other antipsychotics. Potential benefits of atypical compared with typical antipsychotics include the lower propensity to cause over-sedation and movement disorder. Of the second-generation antipsychotics investigated in delirium, most data support the use of risperidone and olanzapine. Other drugs (e.g. aripiprazole, quetiapine, donepezil and flumazenil) have been evaluated but data are limited. Benzodiazepines are the drugs of choice (in addition to antipsychotics) for delirium that is not controlled with an antipsychotic (and can be used alone for the treatment of alcohol and sedative hypnotic withdrawal-related delirium). Lorazepam is the benzodiazepine of choice as it has a rapid onset and shorter duration of action, a low risk of accumulation, no major active metabolites and its bioavailability is more predictable when it is administered both orally and intramuscularly.

Delirium in cancer patients: a focus on treatment-induced psychopathology

PURPOSE OF REVIEW

Delirium is a neuropsychiatric syndrome that occurs frequently in cancer patients, especially in those with advanced disease. Recognition and effective management of delirium is particularly important in supportive and palliative care, especially in view of the projected increase in the elderly population and the consequent potential for the number of patients both diagnosed and living longer with cancer to increase substantively.

RECENT FINDINGS

Studies of delirium in a variety of settings have generated new insights into phenomenology, assessment tools, the psychomotor subtypes, potential patho-physiological markers, pathogenesis, reversibility, and the role of sedation in symptom control.

SUMMARY

Validated tools exist to assist in the assessment of delirium. Although our understanding of the pathogenesis of delirium has improved somewhat, there remains a compelling need to further elucidate the underlying pathophysiology, especially in relation to opioids and the other psychoactive medications that are used in supportive care. Further trials are needed, especially in patients with advanced disease to determine predictive models of reversibility, preventive strategies, outcomes, and to assess the role of antipsychotic and other medications in symptomatic management.

Comparison of short- and long-acting benzodiazepine-receptor agonists with different receptor selectivity on motor coordination and muscle relaxation following thiopental-induced anesthesia in mice

In this study, we compared the effects of Type I benzodiazepine receptor-selective agonists (zolpidem, quazepam) and Type I/II non-selective agonists (zopiclone, triazolam, nitrazepam) with either an ultra-short action (zolpidem, zopiclone, triazolam) or long action (quazepam, nitrazepam) on motor coordination (rota-rod test) and muscle relaxation (traction test) following the recovery from thiopental-induced anesthesia (20 mg/kg) in ddY mice. Zolpidem (3 mg/kg), zopiclone (6 mg/kg), and triazolam (0.3 mg/kg) similarly caused an approximately 2-fold prolongation of the thiopental-induced anesthesia. Nitrazepam (1 mg/kg) and quazepam (3 mg/kg) showed a 6- or 10-fold prolongation of the anesthesia, respectively. Zolpidem and zopiclone had no effect on the rota-rod and traction test. Moreover, zolpidem did not affect motor coordination and caused no muscle relaxation following the recovery from the thiopental-induced anesthesia. However, zopiclone significantly impaired the motor coordination at the beginning of the recovery. Triazolam significantly impaired the motor coordination and muscle relaxant activity by itself, and these impairments were markedly exacerbated after the recovery from anesthesia. Nitrazepam and quazepam significantly impaired motor coordination, and the impairments were exacerbated after the recovery. These results suggest that the profile of recovery of motor coordination and muscle flaccidity after co-administration of benzodiazepine-receptor agonists and thiopental is related to the half-life and selectivity for the benzodiazepine-receptor subtypes.

Children's factual and delusional memories of intensive care

RATIONALE

Delusional memories are significantly associated with post-traumatic stress in adult patients after intensive care.

OBJECTIVES

In this study, we attempted to establish whether this relationship was found in children. We also examined the association between factual memory and distress.

METHODS

One hundred two consecutive children, aged between 7 and 17 years, were interviewed about their pediatric intensive care unit (PICU) experience 3 months after discharge from a PICU. Principal measures were the ICU Memory Tool (a checklist of intensive care memories) and an abbreviated version of the Impact of Event Scale (a screen for post-traumatic stress disorder).

MEASUREMENTS AND MAIN RESULTS

In total, 64 of 102 (63%) children reported at least one factual memory of their admission and 33 of 102 (32%) reported delusional memories, including disturbing hallucinations. Traumatic brain injury was negatively associated with factual memory (odds ratio, 0.23; 95% confidence interval [CI], 0.09-0.58; P = 0.002). Longer duration of opiates/benzodiazepines was associated with delusional memory (odds ratio, 4.98; 95% CI, 1.3-20.0; P = 0.023). Post-traumatic stress scores were higher in children reporting delusional memories (adjusted difference, 3.0; 95% CI, 0.06-5.9; P = 0.045) when illness severity and emergency status were controlled for. Factual memory was not significantly associated with post-traumatic stress.

CONCLUSIONS

This study indicates that delusional memories are reported by almost one-third of children and are associated both with the duration of opiates/benzodiazepines and risk of post-traumatic stress. More research is needed on the presence of delusional memories and associated risk factors in children receiving intensive care treatment.