Variables affecting outcome in critically ill patients

Predictors of growth of Escherichia coli on lab coats as part of hospital-acquired infection transmission through healthcare personnel attire

OBJECTIVES

Previous research has documented the presence of microbes on healthcare personnel (HCP) attire. This study aimed to explore the bacterial contamination and predictors of Escherichia coli (E coli) growth, as well as, hygiene and handling practices of HCP attire that could influence growth of E coli.

METHODS

Descriptive, cross-sectional study was used in this study. Convenience sampling of the 188 HCP was recruited from a main comprehensive hospital in the northern part of Jordan. Three swab samples were collected from three different parts of lab coats used by each participant. The generalised mixed linear model was used for the categorical variables and to identify the predictors of E coli growth on HCP attire.

RESULTS

Enterococcus faecalis was the most common species of bacteria found on lab coat. The HCP attire coming from the emergency department (ED) was highlighted with slightly higher contamination of E coli compared with other departments, such as critical care units. Factors associated with significant E coli growth on HCP attire were lab coat use over scrubs and borrowing of lab coats. The predictors of positive E coli growth were working in the ED, storing HCP attire in hospital lockers, believing the transmission of pathogens by HCP attire and carrying attire wrapped around arms.

IMPLICATIONS

Hygiene practices and policies, including a washing facility on the hospital premises, are a must to keep the lab coats clean.

CONCLUSION

HCP should be cautious about the method of use and storage of lab coats they wear.

Health care-associated infections - an overview

Health care-associated infections (HCAIs) are infections that occur while receiving health care, developed in a hospital or other health care facility that first appear 48 hours or more after hospital admission, or within 30 days after having received health care. Multiple studies indicate that the common types of adverse events affecting hospitalized patients are adverse drug events, HCAIs, and surgical complications. The US Center for Disease Control and Prevention identifies that nearly 1.7 million hospitalized patients annually acquire HCAIs while being treated for other health issues and that more than 98,000 patients (one in 17) die due to these. Several studies suggest that simple infection-control procedures such as cleaning hands with an alcohol-based hand rub can help prevent HCAIs and save lives, reduce morbidity, and minimize health care costs. Routine educational interventions for health care professionals can help change their hand-washing practices to prevent the spread of infection. In support of this, the WHO has produced guidelines to promote hand-washing practices among member countries.

Sepsis Survivors Admitted to Skilled Nursing Facilities: Cognitive Impairment, Activities of Daily Living Dependence, and Survival

OBJECTIVE

Severe sepsis survivors frequently experience cognitive and physical functional impairment. The degree of impairment and its association with mortality is understudied, particularly among those discharged to a skilled nursing facility. Our objective was to quantify the cognitive and physical impairment among severe sepsis survivors discharged to a skilled nursing facility and to investigate the relationship between impairment and long-term mortality.

DESIGN

Retrospective cohort study.

SETTING

United States.

SUBJECTS

Random 5% sample of Medicare patients discharged following severe sepsis hospitalization, 2005-2009 (n = 135,370).

MEASUREMENT AND MAIN RESULTS

Medicare data were linked with the Minimum Data Set; Minimum Data Set-Cognition Scale was used to assess cognitive function, and the Minimum Data Set activities of daily living hierarchical scale was used to assess functional dependence. Associations were evaluated using multivariable logistic regression, Kaplan-Meier curves, and Cox proportional hazards regression. Of 66,540 beneficiaries admitted to a skilled nursing facility following severe sepsis, 34% had severe or very severe cognitive impairment, and 72.5% had maximal, dependence, or total dependence in activities of daily living. Median survival was 19.4 months for those discharged to a skilled nursing facility without having been in a skilled nursing facility in the preceding 1 year and 10.4 months for those discharged to a skilled nursing facility who had spent time in a skilled nursing facility in the prior year. The adjusted hazard ratio for death was 3.1 for those with very severe cognitive impairment relative to those who were cognitively intact (95% CI, 2.9-3.2; p < 0.001) and 4.3 for those with "total dependence" in activities of daily livings relative to those who were independent (95% CI, 3.8-5.0; p < 0.001).

CONCLUSIONS

Discharge to a skilled nursing facility following severe sepsis hospitalization among Medicare beneficiaries was associated with shorter survival, and cognitive impairment and activities of daily living dependence were each strongly associated with shortened survival. These findings can inform decision-making by patients and physicians and underscores high palliative care needs among sepsis survivors discharged to skilled nursing facility.

Sex- and diagnosis-dependent differences in mortality and admission cytokine levels among patients admitted for intensive care

OBJECTIVES

To investigate the role of sex on cytokine expression and mortality in critically ill patients.

DESIGN

A cohort of patients admitted to were enrolled and followed over a 5-year period.

SETTING

Two university-affiliated hospital surgical and trauma ICUs.

PATIENTS

Patients 18 years old and older admitted for at least 48 hours to the surgical or trauma ICU.

INTERVENTIONS

Observation only.

MEASUREMENTS AND MAIN RESULTS

Major outcomes included admission cytokine levels, prevalence of ICU-acquired infection, and mortality during hospitalization conditioned on trauma status and sex. The final cohort included 2,291 patients (1,407 trauma and 884 nontrauma). The prevalence of ICU-acquired infection was similar for men (46.5%) and women (44.5%). All-cause in-hospital mortality was 12.7% for trauma male patient and 9.1% for trauma female patient (p = 0.065) and 22.9% for nontrauma male patients and 20.6% for nontrauma female patients (p = 0.40). Among trauma patients, logistic regression analysis identified female sex as protective for all-cause mortality (odds ratio, 0.57). Among trauma patients, men had significantly higher admission serum levels of interleukin-2, interleukin-12, interferon-γ, and tumor necrosis factor-α, and among nontrauma patients, men had higher admission levels of interleukin-8 and tumor necrosis factor-α.

CONCLUSIONS

The relationship between sex and outcomes in critically ill patients is complex and depends on underlying illness. Women appear to be better adapted to survive traumatic events, while sex may be less important in other forms of critical illness. The mechanisms accounting for this gender dimorphism may, in part, involve differential cytokine responses to injury, with men expressing a more robust proinflammatory profile.

Sepsis-induced Cardiac Mitochondrial Damage and Potential Therapeutic Interventions in the Elderly

The incidence of sepsis and its attendant mortality risk are significantly increased with aging. Thus, severe sepsis in the elderly is likely to become an emerging concern in critical care units. Cardiac dysfunction is an important component of multi-organ failure after sepsis. In our laboratory, utilizing a pneumonia-related sepsis animal model, our research has been focused on the mechanisms underlying sepsis-induced cardiac failure. In this review, based on findings from others and ours, we discussed age-dependent decay in mitochondria and the role of mitochondrial reactive oxygen species (mtROS) in sepsis-induced cardiac inflammation and autophagy. Our recent discovery of a potential signal transduction pathway that triggers myocardial mitochondrial damage is also discussed. Because of the significance of mitochondria damage in the aging process and in sepsis pathogenesis, we hypothesize that specific enhancing mitochondrial antioxidant defense by mitochondria-targeted antioxidants (MTAs) may provide important therapeutic potential in treating elder sepsis patients. In this review, we summarized the categories of currently published MTA molecules and the results of preclinical evaluation of MTAs in sepsis and aging models.

The critical care work environment and nurse-reported health care-associated infections

BACKGROUND

Critically ill patients are susceptible to health care-associated infections because of their illnesses and the need for intravenous access and invasive monitoring. The critical care work environment may influence the likelihood of infection in these patients.

OBJECTIVE

To determine whether or not the critical care nurse work environment is predictive of nurse-reported health care-associated infections.

METHODS

A retrospective, cross-sectional design was used with linked nurse and hospital survey data. Nurses assessed the critical care work environment and provided the frequencies of ventilator-associated pneumonias, urinary tract infections, and infections associated with central catheters. Logistic regression models were used to determine if critical care work environments were predictive of nurse-reported frequent health care-associated infections, with controls for nurse and hospital characteristics. Results The final sample consisted of 3217 critical care nurses in 320 hospitals. Compared with nurses working in poor work environments, nurses working in better work environments were 36% to 41% less likely to report that health care-associated infections occurred frequently.

CONCLUSION

Health care-associated infections are less likely in favorable critical care work environments. These findings, based on the largest sample of critical care nurses to date, substantiate efforts to focus on the quality of the work environment as a way to minimize the frequency of health care-associated infections.

Severe sepsis and septic shock in the elderly: An overview

The incidence of severe sepsis and septic shock is increasing in the older population leading to increased admissions to the intensive care units (ICUs). The elderly are predisposed to sepsis due to co-existing co-morbidities, repeated and prolonged hospitalizations, reduced immunity, functional limitations and above all due to the effects of aging itself. A lower threshold and a higher index of suspicion is required to diagnose sepsis in this patient population because the initial clinical picture may be ambiguous, and aging increases the risk of a sudden deterioration in sepsis to severe sepsis and septic shock. Management is largely based on standard international guidelines with a few modifications. Age itself is an independent risk factor for death in patients with severe sepsis, however, many patients respond well to timely and appropriate interventions. The treatment should not be limited or deferred in elderly patients with severe sepsis only on the grounds of physician prejudice, but patient and family preferences should also be taken into account as the outcomes are not dismal. Future investigations in the management of sepsis should not only target good functional recovery but also ensure social independence and quality of life after ICU discharge.

Severe sepsis and septic shock in the elderly: An overview

The incidence of severe sepsis and septic shock is increasing in the older population leading to increased admissions to the intensive care units (ICUs). The elderly are predisposed to sepsis due to co-existing co-morbidities, repeated and prolonged hospitalizations, reduced immunity, functional limitations and above all due to the effects of aging itself. A lower threshold and a higher index of suspicion is required to diagnose sepsis in this patient population because the initial clinical picture may be ambiguous, and aging increases the risk of a sudden deterioration in sepsis to severe sepsis and septic shock. Management is largely based on standard international guidelines with a few modifications. Age itself is an independent risk factor for death in patients with severe sepsis, however, many patients respond well to timely and appropriate interventions. The treatment should not be limited or deferred in elderly patients with severe sepsis only on the grounds of physician prejudice, but patient and family preferences should also be taken into account as the outcomes are not dismal. Future investigations in the management of sepsis should not only target good functional recovery but also ensure social independence and quality of life after ICU discharge.

Liver X receptor is a key regulator of cytokine release in human monocytes

Aberrant regulation of innate immune responses and uncontrolled cytokine bursts are hallmarks of sepsis and endotoxemia. Activation of the nuclear liver X receptor (LXR) was recently demonstrated to suppress inflammatory genes. Our aim was to investigate the expression of LXR in human monocytes under normal and endotoxemic conditions and to study the influence of LXR activation on endotoxin-induced cytokine synthesis and release. Adherent human monocytes or whole blood were pretreated with a synthetic LXR agonist (3-{3-[(2-chloro-3-trifluoromethyl-benzyl)-(2,2-diphenyl-ethyl)-amino]-propoxy}-phenyl)-acetic acid) and subsequently challenged with LPS (from Escherichia coli) or peptidoglycan (from Staphylococcus aureus). Cytokine release was assessed by a Multiplex antibody bead kit, and cytokine mRNA levels were measured by real-time reverse-transcriptase-polymerase chain reaction. We found that LXRalpha mRNA was up-regulated in CD14+ monocytes in LPS-challenged blood, whereas LXRbeta mRNA was not altered. Addition of 3-{3-[(2-chloro-3-trifluoromethyl-benzyl)-(2,2-diphenyl-ethyl)-amino]-propoxy}-phenyl)-acetic acid to monocytes suppressed the LPS-induced release of IL-1beta, IL-6, IL-8, IL-10, IL-12p40, TMF-alpha, macrophage inflammatory protein 1alpha, macrophage inflammatory protein 1beta, and monocyte chemoattractant protein 1 in a concentration-dependent manner. Surprisingly, an accompanying decrease in cytokine mRNA accumulation was not observed. The suppressed cytokine release could not be explained by a diminished transport of mRNA out of the nucleus or a decreased secretion of cytokines. We propose that LXR is a key regulator of cytokine release in LPS-challenged human monocytes, possibly by interfering with translational events.

Geropharmacology: a primer for advanced practice acute care and critical care nurses, part I

Advanced practice nurses' challenge in managing older adults' medication regimens from an evidence base is difficult because older adults are vulnerable to medication errors and adverse drug reactions related to a number of factors. Predicting patients' responses to drugs is compounded during critical illness, adding to the heterogeneity and unpredictability of drug effects that are prevalent premorbidly. In the first part of this 2-part continuing education series, sources of medication errors and older adults' vulnerability are discussed, including normal changes of aging affecting pharmacokinetics and pharmacodynamics, polypharmacy, self-medicating, patient-family noncompliance, and inappropriately prescribed medications. In the second part, drug classes and drugs posing particular problems for older adults and cautions for acute care and critical care nurses who manage the medications of older adults are highlighted.

Mortality and length-of-stay outcomes, 1993-2003, in the binational Australian and New Zealand intensive care adult patient database

OBJECTIVE

Intensive care unit (ICU) outcomes have been the subject of controversy. The objective was to model hospital mortality and ICU length-of-stay time-change of patients recorded in the Australian and New Zealand Intensive Care Society adult patient database.

DESIGN

Retrospective, cohort study of prospectively collected data on index patient admissions.

SETTING

Australian and New Zealand ICUs, 1993-2003.

PATIENTS

The Australian and New Zealand Intensive Care Society adult patient database, which contains data for 223,129 patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Hospital mortality and ICU length of stay were modeled using logistic and linear regression, respectively, with determination (80%) and validation (20%) data sets. Model adequacy was assessed by discrimination (receiver operating characteristic curve area, AZ) and calibration (Hosmer-Lemeshow C) for mortality and R2 for length of stay. Predictor variables included patient demographics, severity score, surgical and ventilation status, ICU categories, and geographical locality. The data set comprised 223,129 patients: Their mean (SD) age was 59.2 (18.9) yrs, 41.7% were female, their mean (SD) Acute Physiology and Chronic Health Evaluation (APACHE) III score was 53 (31), they had 16.1% overall mortality rate, and 45.7% were mechanically ventilated. ICU length of stay was 3.6 (5.6) days. A(Z), C statistic, and R2 for developmental and validation model data sets were 0.88, 17.64 (p = .02), and 0.18; and 0.88, 12.32 (p = .26), and 0.18, respectively. Variables with mortality impact (p < or = .001) were age (odds ratio [OR] 1.023), gender (OR 1.16; males vs. females), APACHE III score (OR 1.06), mechanical ventilation (OR 1.66), and surgical status (elective, OR 0.17; emergency, OR 0.47; compared with nonsurgical). ICU level and locality had significant mortality-time effects. Similar variables were found to predict length of stay. Risk-adjusted mortality declined, during 1993-2003, from 0.19 (95% confidence interval 0.17-0.21) to 0.15 (0.13-0.16) and similarly for ventilated patients: 0.26 (0.24-0.29) to 0.23 (0.21-0.25). Predicted mean ICU length of stay (days) demonstrated minimal overall time-change: 3.4 (2.2) in 1993 to 3.5 (2.7) in 2003, peaking at 3.7 (2.4) in 2000.

CONCLUSIONS

Overall hospital mortality rate in patients admitted to Australian and New Zealand ICUs decreased 4% over 11 yrs. A similar trend occurred for mechanically ventilated patients. Length of stay changed minimally over this period.

Lipid Rafts Regulate Lipopolysaccharide-induced Activation of Cdc42 and Inflammatory Functions of the Human Neutrophil

Lipid rafts are cholesterol-rich membrane microdomains that are thought to act as coordinated signaling platforms by regulating dynamic, agonist-induced translocation of signaling proteins. They have been described to play a role in multiple prototypical cascades, among them the lipopolysaccharide pathway, and to host multiple signaling proteins, including kinases and low molecular weight G-proteins. Here we report lipopolysaccharide-induced activation of the Rho family GTPase Cdc42, and we show its activation in the human neutrophil to be mediated by a p38 mitogen-activated protein kinase-dependent mechanism. Subcellular fractionation reveals that lipopolysaccharide induces translocation of Cdc42 to lipid rafts, where it and p38 are both found to be activated. By contrast, lipopolysaccharide causes translocation of Rac from the polymorphonuclear leukocyte (PMN) rafts and does not induce its activation. With the use of methyl-beta-cyclodextrin, a cholesterol-depleting agent that reversibly disrupts rafts, we confirm an important regulatory role for rafts in the activation state of p38 and Cdc42 and in the Rho GTPase-dependent functions superoxide anion production and actin polymerization. Methyl-beta-cyclodextrin induces activation of p38 and Cdc42, but not Rac, in the nonstimulated PMN, yet inhibits subsequent lipopolysaccharide-induced activation of p38 and Cdc42. In parallel, methyl-beta-cyclodextrin primes the human PMN for subsequent superoxide release triggered by the formylated bacterial tripeptide formyl-Met-Leu-Phe, and induces actin polymerization in a subcellular distribution distinct from that induced by lipopolysaccharide. In sum, these findings provide evidence for an important regulatory role of cholesterol in both transmission of the lipopolysaccharide signal and the inflammatory phenotype of the human neutrophil.

Endocrinologic response to vasopressin infusion in advanced vasodilatory shock

OBJECTIVES

To evaluate the endocrinologic response to a combined arginine vasopressin and norepinephrine (AVP/NE) infusion in advanced vasodilatory shock, and to examine the relationship between baseline plasma AVP concentrations and the hemodynamic response to AVP.

DESIGN

Preliminary, prospective, randomized, controlled clinical study.

SETTING

Twenty-three-bed general and surgical intensive care unit.

PATIENTS

Thirty-eight patients with advanced vasodilatory shock. Hemodynamic and laboratory data of 34 patients have already been presented in a recently published prospective, randomized, controlled study.

INTERVENTIONS

Continuous AVP (4 units/hr) and NE infusion in study patients; NE infusion only in control patients.

MEASUREMENTS AND MAIN RESULTS

At baseline, 24 hrs, and 48 hrs after randomization, plasma concentrations of AVP, adrenocorticotropic hormone, cortisol, renin, angiotensin II, aldosterone, prolactin, endothelin I, and atrial natriuretic factor were determined. Hemodynamic variables were recorded at baseline and 1, 12, and 24 hrs after randomization. Linear mixed effects models were used to test for differences between groups. The relationship between AVP plasma concentrations and hemodynamic response to AVP was analyzed using linear regression analyses. AVP/NE patients exhibited significantly higher AVP (p <.001) and prolactin (p <.001) plasma concentrations during the study period; there were no significant differences in plasma concentrations of other hormones. No significant correlation was detected between plasma AVP concentrations and the increase in mean arterial pressure after 1 hr (Pearson's correlation coefficient =.134, p =.584) and after 24 hrs (Pearson's correlation coefficient = -.198, p =.417). There were further no correlations between AVP plasma concentrations and the 24-hr response to AVP therapy in heart rate (Pearson's correlation coefficient = -.065, p =.791), stroke volume index (Pearson's correlation coefficient = -.106, p =.687), and NE requirements (Pearson's correlation coefficient =.04, p =.869).

CONCLUSIONS

The preliminary results of this study indicate that a combined AVP and NE infusion increases prolactin plasma concentrations in advanced vasodilatory shock. Hemodynamic effects of AVP infusion are independent of baseline plasma AVP concentrations.

Low serum total cholesterol is associated with marked increase in mortality in advanced heart failure

BACKGROUND

Although hypercholesterolemia is a well-defined risk factor for morbidity and mortality in coronary artery disease, the relationship between cholesterol and heart failure (HF) has rarely been investigated.

METHODS

Cholesterol and lipoproteins were measured in 1,134 patients with advanced HF who presented to a single center for HF management and transplant evaluation. Patients were stratified into five groups based on quintiles of total cholesterol (TC) level, and differences in patient characteristics and survival were evaluated.

RESULTS

Patients with low TC had significantly lower low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides (TG), sodium, albumin, left ventricular ejection fraction, and cardiac output. The TC quintiles were similar in terms of HF etiology, hypertension, diabetes, and lipid-lowering therapy at time of referral. TC, LDL, HDL, and TG each predicted survival (P < or = .01) on univariate analysis, with improved survival at higher levels. After adjustment for risk factors using a Cox proportional hazards model, relative risks were 2.071, 1.369, 1.391, 1.006 for the first, second, third, and fourth TC quintiles, with quintile 5 as reference.

CONCLUSIONS

Serum TC represents a novel prognostic factor for patients with advanced HF. Further studies are necessary to investigate a potential role of low cholesterol and lipoproteins in the pathophysiology of HF progression.

Changes in the plasma lipid profile as a potential predictor of clinical outcome in dengue hemorrhagic fever

In 50 consecutive children admitted to the intensive care unit with the clinical diagnosis of dengue hemorrhagic fever (DHF)/dengue shock syndrome (grade III or IV), 20 patients with mild DHF (grade I or II), and 20 healthy control patients, the plasma lipid profile was measured. Levels of total plasma cholesterol, high-density lipoprotein, and low-density lipoprotein were significantly decreased in patients with the severest cases, compared with patients with mild DHF and healthy controls. Changes in the plasma lipid profile differentiate between patients with different stages of DHF disease severity and could be used as a potential predictor for clinical outcome.