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Tuesday 18 October 2016

Long-Term Mental Health Problems After Delirium in the ICU

Long-Term Mental Health Problems After Delirium in the ICU

Wolters, A et al

Critical Care Medicine October 2016 - Volume 44 - Issue 10 - p 1808–1813


Objectives: To determine whether delirium during ICU stay is associated with long-term mental health problems defined as symptoms of anxiety, depression, and posttraumatic stress disorder. Design: Prospective cohort study. Setting: Survey study, 1 year after discharge from a medical-surgical ICU in the Netherlands. Patients: One-year ICU survivors of an ICU admission lasting more than 48 hours, without a neurologic disorder or other condition that would impede delirium assessment during ICU stay. Interventions: None. 
Measurements and Main Results: One year after discharge, ICU survivors received a survey containing the Hospital Anxiety and Depression Scale with a subscale for symptoms of depression and a subscale for symptoms of anxiety, and the Impact of Event Scale 15 item measuring symptoms of posttraumatic stress disorder. Participants were classified as having experienced no delirium (n = 270; 48%), a single day of delirium (n = 86; 15%), or multiple days of delirium (n = 211; 37%) during ICU stay. Log-binomial regression was used to assess the association between delirium and symptoms of anxiety, depression, and posttraumatic stress disorder. The study population consisted of 567 subjects; of whom 246 subjects (43%) reported symptoms of anxiety (Hospital Anxiety and Depression Scale with a subscale for anxiety, ≥ 8), and 254 (45%) symptoms of depression (Hospital Anxiety and Depression Scale with a subscale for depression, ≥ 8). In 220 patients (39%), the Impact of Event Scale 15 item was greater than or equal to 35, indicating a high probability of posttraumatic stress disorder. There was substantial overlap between these mental health problems—63% of the subjects who scored positive for the presence of any three of the mental health problems, scored positive for all three. No association was observed between either a single day or multiple days of delirium and symptoms of anxiety, depression, or posttraumatic stress disorder. 
Conclusions: Although symptoms of anxiety, depression, and posttraumatic stress disorder were found to be common 1 year after critical illness, the occurrence of delirium during ICU stay did not increase the risk of these long-term mental health problems.

Association Among ICU Congestion, ICU Admission Decision, and Patient Outcomes

Association Among ICU Congestion, ICU Admission Decision, and Patient Outcomes

Kim, S et al

Critical Care Medicine: October 2016 - Volume 44 - Issue 10 - p 1814–1821

Objectives: To employ automated bed data to examine whether ICU occupancy influences ICU admission decisions and patient outcomes. 

Design: Retrospective study using an instrumental variable to remove biases from unobserved differences in illness severity for patients admitted to ICU. Setting: Fifteen hospitals in an integrated healthcare delivery system in California. Patients: Seventy thousand one hundred thirty-three episodes involving patients admitted via emergency departments to a medical service over a 1-year period between 2008 and 2009. Interventions: None. 
Measurements and Main Results: A third of patients admitted via emergency department to a medical service were admitted under high ICU congestion (more than 90% of beds occupied). High ICU congestion was associated with a 9% lower likelihood of ICU admission for patients defined as eligible for ICU admission. We further found strong associations between ICU admission and patient outcomes, with a 32% lower likelihood of hospital readmission if the first inpatient unit was an ICU. Similarly, hospital length of stay decreased by 33% and likelihood of transfer to ICU from other units—including ICU readmission if the first unit was an ICU—decreased by 73%. 
Conclusions: High ICU congestion is associated with a lower likelihood of ICU admission, which has important operational implications and can affect patient outcomes. By taking advantage of our ability to identify a subset of patients whose ICU admission decisions are affected by congestion, we found that, if congestion were not a barrier and more eligible patients were admitted to ICU, this hospital system could save approximately 7.5 hospital readmissions and 253.8 hospital days per year. These findings could help inform future capacity planning and staffing decisions.

Cumulative Fluid Balance and Mortality in Septic Patients With or Without Acute Kidney Injury and Chronic Kidney Disease

Cumulative Fluid Balance and Mortality in Septic Patients With or Without Acute Kidney Injury and Chronic Kidney Disease
Neyra JA et al
Critical Care Medicine October 2016 Volume 44 - Issue 10 - p 1891–1900

Objective: Incident acute kidney injury and prevalent chronic kidney disease are commonly encountered in septic patients. We examined the differential effect of acute kidney injury and chronic kidney disease on the association between cumulative fluid balance and hospital mortality in critically ill septic patients. 
Design: Retrospective cohort study. Setting: Urban academic medical center ICU. Patients: ICU adult patients with severe sepsis or septic shock and serum creatinine measured within 3 months prior to and 72 hours of ICU admission. Patients with estimated glomerular filtration rate less than 15 mL/min/1.73 m2 or receiving chronic dialysis were excluded. Interventions: None. 
Measurements and Main Results: A total of 2,632 patients, 1,211 with chronic kidney disease, were followed up until hospital death or discharge. Acute kidney injury occurred in 1,525 patients (57.9%), of whom 679 (44.5%) had chronic kidney disease. Hospital mortality occurred in 603 patients (22.9%). Every 1-L increase in cumulative fluid balance at 72 hours of ICU admission was independently associated with hospital mortality in all patients (adjusted odds ratio, 1.06 [95% CI] 1.04–1.08; p < 0.001), and in each acute kidney injury/chronic kidney disease subgroup (adjusted odds ratio, 1.06 [1.03–1.09] for acute kidney injury+/chronic kidney disease+; 1.09 [1.05–1.13] for acute kidney injury–/chronic kidney disease+; 1.05 [1.03–1.08] for acute kidney injury+/chronic kidney disease–; and 1.07 [1.02–1.11] for acute kidney injury–/chronic kidney disease–). There was a significant interaction between acute kidney injury and chronic kidney disease on cumulative fluid balance (p =0.005) such that different cumulative fluid balance cut-offs with the best prognostic accuracy for hospital mortality were identified: 5.9 L for acute kidney injury+/chronic kidney disease+; 3.8 L for acute kidney injury–/chronic kidney disease+; 4.3 L for acute kidney injury+/chronic kidney disease–; and 1.5 L for acute kidney injury–/chronic kidney disease–. The addition of cumulative fluid balance to the admission Sequential Organ Failure Assessment score had increased prognostic utility for hospital mortality when compared with Sequential Organ Failure Assessment alone, particularly in patients with acute kidney injury. 
Conclusions: Higher cumulative fluid balance at 72 hours of ICU admission was independently associated with hospital mortality regardless of acute kidney injury or chronic kidney disease presence. We characterized cumulative fluid balance cut-offs associated with hospital mortality based on acute kidney injury/chronic kidney disease status, underpinning the heterogeneity of fluid regulation in sepsis and kidney disease.

Effect of Chlorhexidine Bathing Every Other Day on Prevention of Hospital-Acquired Infections in the Surgical ICU: A Single-Center, Randomized Controlled Trial

Effect of Chlorhexidine Bathing Every Other Day on Prevention of Hospital-Acquired Infections in the Surgical ICU: A Single-Center, Randomized Controlled Trial
Swan JT et al 
Critical Care Medicine October 2016 - Volume 44 - Issue 10 - p 1822–1832

Objective: To test the hypothesis that compared with daily soap and water bathing, 2% chlorhexidine gluconate bathing every other day for up to 28 days decreases the risk of hospital-acquired catheter-associated urinary tract infection, ventilator-associated pneumonia, incisional surgical site infection, and primary bloodstream infection in surgical ICU patients. 
Design: This was a single-center, pragmatic, randomized trial. Patients and clinicians were aware of treatment-group assignment; investigators who determined outcomes were blinded. Setting: Twenty-four–bed surgical ICU at a quaternary academic medical center. Patients: Adults admitted to the surgical ICU from July 2012 to May 2013 with an anticipated surgical ICU stay for 48 hours or more were included. Interventions: Patients were randomized to bathing with 2% chlorhexidine every other day alternating with soap and water every other day (treatment arm) or to bathing with soap and water daily (control arm). 
Measurements and Main Results: The primary endpoint was a composite outcome of catheter-associated urinary tract infection, ventilator-associated pneumonia, incisional surgical site infection, and primary bloodstream infection. Of 350 patients randomized, 24 were excluded due to prior enrollment in this trial and one withdrew consent. Therefore, 325 were analyzed (164 soap and water versus 161 chlorhexidine). Patients acquired 53 infections. Compared with soap and water bathing, chlorhexidine bathing every other day decreased the risk of acquiring infections (hazard ratio = 0.555; 95% CI, 0.309–0.997; p = 0.049). For patients bathed with soap and water versus chlorhexidine, counts of incident hospital-acquired infections were 14 versus 7 for catheter-associated urinary tract infection, 13 versus 8 for ventilator-associated pneumonia, 6 versus 3 for incisional surgical site infections, and 2 versus 0 for primary bloodstream infection; the effect was consistent across all infections. The absolute risk reduction for acquiring a hospital-acquired infection was 9.0% (95% CI, 1.5–16.4%; p = 0.019). Incidences of adverse skin occurrences were similar (18.9% soap and water vs 18.6% chlorhexidine; p = 0.95). 
Conclusions: Compared with soap and water, chlorhexidine bathing every other day decreased the risk of acquiring infections by 44.5% in surgical ICU patients.

Risk of Recurrence After Surviving Severe Sepsis: A Matched Cohort Study

Risk of Recurrence After Surviving Severe Sepsis: A Matched Cohort Study
Shen H et al
Critical Care Medicine October 2016 - Volume 44 - Issue 10 - p 1833–1841

Objectives: To examine the risk of recurrence in adults who survived first-episode severe sepsis for at least 3 months. 
Design: A matched cohort study. Setting: Inpatient claims data from Taiwan’s National Health Insurance Research Database. Subjects: We analyzed 10,818 adults who survived first-episode severe sepsis without recurrence for at least 3 months in 2000 (SS group; mean age, 62.7 yr; men, 54.7%) and a group of age/sex-matched (1:1) population controls who had no prior history of severe sepsis. All subjects were followed from the study entry to the occurrence of end-point, death, or until December 31, 2008, whichever date came first. Interventions: None. Measurements and Main 
Results: Primary end-point was severe sepsis that occurred after January 1, 2001 (the study entry). Relative risk of the end-point was assessed using competing risk regression model. During the follow-up period, severe sepsis and death occurred in 35.0% and 26.5% of SS group and in 4.3% and 18.6% of controls, respectively, representing a covariate-adjusted sub–hazard ratio of 8.89 (95% CI, 8.04–9.83) for the risk of recurrence. In stratified analysis by patient characteristics, the sub–hazard ratios ranged from 7.74 in rural area residents to 23.17 in young adults. In subgroup analysis by first-episode infection sites in SS group, the sub–hazard ratios ranged from 4.82 in intra-abdominal infection to 9.99 in urinary tract infection. 
Conclusions: Risk of recurrence after surviving severe sepsis is substantial regardless of patient characteristics or infection sites. Further research is necessary to find underlying mechanisms for the high risk of recurrence in these patients.

Endothelial Activation and Blood-Brain Barrier Injury as Risk Factors for Delirium in Critically Ill Patients

Endothelial Activation and Blood-Brain Barrier Injury as Risk Factors for Delirium in Critically Ill Patients
Hughes C et al
Critical Care Medicine September 2016 - Volume 44 - Issue 9 - p e809–e817

Objectives: During critical illness, impaired endothelial vascular reactivity predicts prolonged acute brain dysfunction, but relationships between endothelial activation, blood-brain barrier/neurological injury, and acute brain dysfunction, including delirium, remain unexamined. We tested the hypothesis that elevated plasma markers of endothelial activation and blood-brain barrier/neurological injury are associated with delirium duration during critical illness. 
Design: Prospective cohort study. Setting: Medical and surgical ICUs in an academic medical center. Patients: Adults in acute respiratory failure and/or shock. Interventions: None. 
Measurements and Main Results: We enrolled subjects within 72 hours of organ failure diagnosis in the ICU. We measured plasma concentrations of plasminogen activator inhibitor-1, E-selectin, and angiopoietin-2 as markers of endothelial activation and S100B as a marker of blood-brain barrier/neurological injury in blood collected at enrollment. We assessed patients for delirium and coma twice daily after enrollment using the Confusion Assessment Method for the ICU and the Richmond Agitation-Sedation Scale. Among 134 patients with a median (interquartile) age of 57 years (46–66 yr) and Acute Physiology and Chronic Health Evaluation II of 26 (19–31), delirium occurred in 94 patients (70%) with a median duration of 2 days (0–4 d). Higher plasminogen activator inhibitor-1 (p = 0.002), E-selectin (p = 0.02), and S100B (p < 0.001) concentrations were associated with fewer delirium/coma-free days after adjusting for age, Charlson comorbidity index, modified Sequential Organ Failure Assessment score, and severe sepsis. Similarly, higher plasminogen activator inhibitor-1 (p = 0.007) and S100B (p = 0.01) concentrations were associated with longer delirium duration in survivors. Adjusting for S100B did not alter plasminogen activator inhibitor-1 and E-selectin associations with delirium, suggesting that these associations were not mediated by blood-brain barrier/neurological injury. 
Conclusions: Elevated plasma markers of endothelial activation and blood-brain barrier/neurological injury during critical illness are associated with prolonged delirium after biomarker measurement. Future research is needed to determine whether these processes have pathophysiologic roles in delirium and whether therapies targeted at the endothelium or blood-brain barrier can prevent and/or treat delirium during critical illness.