BackgroundAlthough alert fatigue is blamed for high override rates in contemporary clinical decision support systems, the concept of alert fatigue is poorly defined. We tested hypotheses arising from two possible alert fatigue mechanisms: (A) cognitive overload associated with amount of work, complexity of work, and effort distinguishing informative from uninformative alerts, and (B) desensitization from repeated exposure to the same alert over time.MethodsRetrospective cohort study using electronic health record data (both drug alerts and clinical practice reminders) from January 2010 through June 2013 from 112 ambulatory primary care clinicians. The cognitive overload hypotheses were that alert acceptance would be lower with higher workload (number of encounters, number of patients), higher work complexity (patient comorbidity, alerts per encounter), and more alerts low in informational value (repeated alerts for the same patient in the same year). The desensitization hypothesis was that, for newly deployed alerts, acceptance rates would decline after an initial peak.ResultsOn average, one-quarter of drug alerts received by a primary care clinician, and one-third of clinical reminders, were repeats for the same patient within the same year. Alert acceptance was associated with work complexity and repeated alerts, but not with the amount of work. Likelihood of reminder acceptance dropped by 30% for each additional reminder received per encounter, and by 10% for each five percentage point increase in proportion of repeated reminders. The newly deployed reminders did not show a pattern of declining response rates over time, which would have been consistent with desensitization. Interestingly, nurse practitioners were 4 times as likely to accept drug alerts as physicians.ConclusionsClinicians became less likely to accept alerts as they received more of them, particularly more repeated alerts. There was no evidence of an effect of workload per se, or of desensitization over time for a newly deployed alert. Reducing within-patient repeats may be a promising target for reducing alert overrides and alert fatigue.

Objective Delirium occurs frequently in adults, and is an independent predictor of mortality. However, the epidemiology and outcomes of pediatric delirium are not well-characterized. The primary objectives of this study were to describe the incidence of delirium in critically ill children, its duration, associated risk factors, and effect on in-hospital outcomes, including mortality. Secondary objectives included determination of delirium subtype, and effect of delirium on duration of mechanical ventilation (MV), and length of hospital stay (LOS). Design Prospective longitudinal cohort study. Setting Urban academic tertiary care pediatric intensive care unit (PICU). Patients All consecutive admissions from September 2014 through August 2015. Intervention Children were screened for delirium twice daily throughout their ICU stay. Measurements and Main Results Of 1547 consecutive patients, delirium was diagnosed in 267 (17%), and lasted a median of two days (IQR 1,5). Seventy-eight percent of children with delirium developed it within the first three PICU days. Most cases of delirium were of the hypoactive (46%) and mixed (45%) subtypes; only 8% of delirium episodes were characterized as hyperactive delirium. In multivariable analysis, independent predictors of delirium included age ≤2 years, developmental delay, severity of illness, prior coma, mechanical ventilation, and receipt of benzodiazepines and anticholinergics. PICU LOS was increased in children with delirium (adjusted relative LOS 2.3, CI= 2.1, 2.5, p<0.001), as was duration of MV (median 4 vs. 1 day, p<0.001). Delirium was a strong and independent predictor of mortality (adjusted OR 4.39, CI= 1.96–9.99, p<0.001). Conclusions Delirium occurs frequently in critically ill children and is independently associated with mortality. Some in-hospital risk factors for delirium development are modifiable. Interventional studies are needed to determine best practices to limit delirium exposure in at-risk children.

Background Delirium is acute brain dysfunction associated with serious illness. Emerging data indicate that delirium occurs in greater than 20% of children in pediatric intensive care units. Cardiac bypass surgery is a known risk factor for delirium in adults, but has never been systematically studied in pediatrics. Objectives To describe the incidence of delirium in pediatric patients after cardiac bypass surgery, and explore associated risk factors and effect of delirium on in-hospital outcomes. Design Prospective observational single-center study. Setting Fourteen-bed pediatric cardiothoracic intensive care unit (PCICU). Patients One hundred and ninety four consecutive admissions following cardiac bypass surgery, age one day to 21 years. Interventions Subjects were screened for delirium daily using the Cornell Assessment of Pediatric Delirium. Measurements and Main Results Incidence of delirium in this sample was 49%. Delirium most often lasted 1–2 days, and developed within the first 1–3 days after surgery. Age less than two years, developmental delay, higher RACHS-1 score, cyanotic disease, and albumin less than three were all independently associated with development of delirium in a multivariable model (all p values <0.03). Delirium was an independent predictor of prolonged ICU LOS, with patients who were ever delirious having a 60% increase in ICU days compared to patients who were never delirious (p<0.01). Conclusions In our institution, delirium is a frequent problem in children after cardiac bypass surgery, with identifiable risk factors. Our study suggests that cardiac bypass surgery significantly increases children’s susceptibility to delirium. This highlights the need for heightened, targeted delirium screening in all PCICUs to potentially improve outcomes in this vulnerable patient population.

Objective To determine the costs associated with delirium in critically ill children. Design Prospective observational study. Setting An urban, academic, tertiary-care pediatric intensive care unit (PICU) in New York City. Patients Four-hundred and sixty-four consecutive PICU admissions between 9/2/2014 and 12/19/2014. Interventions None. Measurements and Main Results All children were assessed for delirium daily throughout their PICU stay. Hospital costs were analyzed using cost-to-charge ratios, in 2014 dollars. Median total PICU costs were higher in patients with delirium than in patients who were never delirious ($18,832 vs. $4,803, p<0.0001). Costs increased incrementally with number of days spent delirious (median cost of $9,173 for 1 day with delirium, $19,682 for 2–3 days with delirium, and $75,833 for >3 days with delirium, p<0.0001); this remained highly significant even after adjusting for PICU length of stay (p<0.0001). After controlling for age, gender, severity of illness, and PICU length of stay, delirium was associated with an 85% increase in PICU costs (p<0.0001). Conclusions Pediatric delirium is associated with a major increase in PICU costs. Further research directed at prevention and treatment of pediatric delirium is essential to improve outcomes in this population, and could lead to substantial healthcare savings.

Benzodiazepines are an independent and modifiable risk factor for development of delirium in critically ill children, even after carefully controlling for time-dependent covariates, with a dose-response effect. This temporal relationship suggests causality between benzodiazepine exposure and pediatric delirium and supports limiting the use of benzodiazepines in critically ill children.