Epidemiology of intra-abdominal infection and sepsis in critically ill patients: "AbSeS", a multinational observational cohort study and ESICM Trials Group Project

Purpose

To describe the epidemiology of intra-abdominal infection in an international cohort of ICU patients according to a new system that classifies cases according to setting of infection acquisition (community-acquired, early onset hospital-acquired, and late-onset hospital-acquired), anatomical disruption (absent or present with localized or diffuse peritonitis), and severity of disease expression (infection, sepsis, and septic shock).

Methods

We performed a multicenter (n = 309), observational, epidemiological study including adult ICU patients diagnosed with intra-abdominal infection. Risk factors for mortality were assessed by logistic regression analysis.

Results

The cohort included 2621 patients. Setting of infection acquisition was community-acquired in 31.6%, early onset hospital-acquired in 25%, and late-onset hospital-acquired in 43.4% of patients. Overall prevalence of antimicrobial resistance was 26.3% and difficult-to-treat resistant Gram-negative bacteria 4.3%, with great variation according to geographic region. No difference in prevalence of antimicrobial resistance was observed according to setting of infection acquisition. Overall mortality was 29.1%. Independent risk factors for mortality included late-onset hospital-acquired infection, diffuse peritonitis, sepsis, septic shock, older age, malnutrition, liver failure, congestive heart failure, antimicrobial resistance (either methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, extended-spectrum beta-lactamase-producing Gram-negative bacteria, or carbapenem-resistant Gram-negative bacteria) and source control failure evidenced by either the need for surgical revision or persistent inflammation.

Conclusion

This multinational, heterogeneous cohort of ICU patients with intra-abdominal infection revealed that setting of infection acquisition, anatomical disruption, and severity of disease expression are disease-specific phenotypic characteristics associated with outcome, irrespective of the type of infection. Antimicrobial resistance is equally common in community-acquired as in hospital-acquired infection.

Electronic supplementary material

The online version of this article (10.1007/s00134-019-05819-3) contains supplementary material, which is available to authorized users.

Behavioral determinants of hand hygiene compliance in intensive care units

BACKGROUND

Although hand hygiene is the most effective measure for preventing cross-infection, overall compliance is poor among health care workers.

OBJECTIVES

To identify and describe predictors and determinants of noncompliance with hand hygiene prescriptions in intensive care unit nurses by means of a questionnaire.

METHODS

A questionnaire based on a behavioral theory model was filled out by 148 nurses working on a 40-bed intensive care unit in a university hospital. Subjects were asked to fill out the 56-item questionnaire twice within a 2- to 6-week period. During this period, no interventions to enforce hand hygiene occurred on the unit.

RESULTS

Response rate for the test was 73% (108/148); response rate for the retest was 53% (57/108). The mean self-reported compliance rate was 84%. Factor analysis revealed 8 elementary factors potentially associated with compliance. Internal consistency of the scales was acceptable. Intraclass correlation was low (<0.60) for 2 subscales but acceptable (>0.60) for 6 subscales. A low self-efficacy was independently associated with noncompliance (beta = .379; P = .001). After exclusion of this variable, a negative attitude toward time-related barriers was associated with noncompliance (beta = -.147; P < .001).

CONCLUSIONS

Neither having good theoretical knowledge of hand hygiene guidelines nor social influence or moral perceptions had any predictive value relative to hand hygiene practice. A valid questionnaire to identify predictors and determinants of noncompliance with hand hygiene has been designed. Nurses reporting a poor self-efficacy or a poor attitude toward time-related barriers appear to be less compliant.

Critical Care Nurses’ Knowledge of Evidence-Based Guidelines for Preventing Ventilator-Associated Pneumonia: An Evaluation Questionnaire

Background Nurses’ lack of knowledge may be a barrier to adherence to evidence-based guidelines for preventing ventilator-associated pneumonia.

Objective To develop a reliable and valid questionnaire for evaluating critical care nurses’ knowledge of evidence-based guidelines for preventing ventilator-associated pneumonia.

Methods Ten nursing-related interventions were identified from a review of evidence-based guidelines for preventing ventilator-associated pneumonia. Selected interventions and multiple-choice questions (1 question per intervention) were subjected to face and content validation. Item difficulty, item discrimination, and the quality of the response alternatives or options for answers (possible responses) were evaluated on the test results of 638 critical care nurses.

Results Face and content validity were achieved for 9 items. Values for item difficulty ranged from 0.1 to 0.9. Values for item discrimination ranged from 0.10 to 0.65. The quality of the response alternatives led to the detection of widespread misconceptions among critical care nurses.

Conclusion The questionnaire is reliable and has face and content validity. Results of surveys with this questionnaire can be used to focus educational programs on preventing ventilator-associated pneumonia.

Cuff pressure of endotracheal tubes after changes in body position in critically ill patients treated with mechanical ventilation

BACKGROUND

In order to avoid microaspiration and tracheal injury, the target for endotracheal tube cuff pressure is 20 to 30 cm H2O.

OBJECTIVE

To assess the effect of changes in body position on cuff pressure in adult patients.

METHODS

Twelve orally intubated and sedated patients received neuromuscular blockers and were positioned in a neutral starting position (backrest, head-of-bed elevation 30º, head in neutral position) with cuff pressure at 25 cm H2O. Then, 16 changes in position were performed: anteflexion head, hyperextension head, left and right lateral flexion of head, left and right rotation of the head, semirecumbent position (head-of-bed elevation 45°), recumbent position (head-of-bed elevation 10°), horizontal backrest, Trendelenburg position (10°), and left and right lateral positioning over 30°, 45°, and 90°. Once a patient was correctly positioned, cuff pressure was recorded during an end-expiratory ventilatory hold. The pressure observed was compared with the cuff pressure at the starting position. Values outside the target range (20-30 cm H2O) were considered clinically relevant.

RESULTS

A total of 192 measurements were performed (12 subjects × 16 positions). A significant deviation in cuff pressure occurred with all 16 changes (P < .05). No pressures were less than the lower limit (20 cm H2O). Pressures were greater than the upper limit (30 cm H2O) in 40.6% of the measurements. In each position, the upper target limit was exceeded at least once. Within-patient variability was substantial (P = .02).

CONCLUSION

Simple changes in patients' positioning can result in potentially harmful cuff pressures.

Evidence-based guidelines for the prevention of ventilator-associated pneumonia: results of a knowledge test among intensive care nurses

OBJECTIVE

To determine intensive care nurses' knowledge of evidence-based guidelines for the prevention of ventilator-associated pneumonia (VAP).

DESIGN

A survey using a validated multiple-choice questionnaire, developed to evaluate nurses' knowledge of VAP prevention. The questionnaire was distributed and collected during the annual congress of the Flemish Society for Critical Care Nurses (Ghent, November 2005). Demographic data included were gender, years of intensive care experience, number of critical beds, and whether respondents hold a special degree in emergency and intensive care.

MAIN RESULTS

We collected 638 questionnaires (response rate 74.6%). Nineteen percent of the respondents recognized the oral route as the recommended way for intubation. It was known by 49% of respondents that ventilator circuits should be changed for each new patient. Heat and moisture exchangers were checked as the recommended type of humidifier by 55% of respondents, but only 13% knew that it is recommended to change them once weekly. Closed suctioning systems were identified as recommended by 17% of respondents, and 20% knew that these must be changed for each new patient only. Sixty percent and 49%, respectively, recognized subglottic drainage and kinetic beds to reduce the incidence of VAP. Semi-recumbent positioning is well known to prevent VAP (90%). The average knowledge level was higher among more experienced nurses (> 1 year experience) and those holding a special degree in emergency and intensive care.

CONCLUSION

Nurses lack knowledge regarding recommendations for VAP prevention. Nurses' schooling and continuing education should include support from current evidence-based guidelines.

Value of lower respiratory tract surveillance cultures to predict bacterial pathogens in ventilator-associated pneumonia: systematic review and diagnostic test accuracy meta-analysis

PURPOSE

In ventilator-associated pneumonia (VAP), early appropriate antimicrobial therapy may be hampered by involvement of multidrug-resistant (MDR) pathogens.

METHODS

A systematic review and diagnostic test accuracy meta-analysis were performed to analyse whether lower respiratory tract surveillance cultures accurately predict the causative pathogens of subsequent VAP in adult patients. Selection and assessment of eligibility were performed by three investigators by mutual consideration. Of the 525 studies retrieved, 14 were eligible for inclusion (all in English; published since 1994), accounting for 791 VAP episodes. The following data were collected: study and population characteristics; in- and exclusion criteria; diagnostic criteria for VAP; microbiological workup of surveillance and diagnostic VAP cultures. Sub-analyses were conducted for VAP caused by Staphylococcus aureus, Pseudomonas spp., and Acinetobacter spp., MDR microorganisms, frequency of sampling, and consideration of all versus the most recent surveillance cultures.

RESULTS

The meta-analysis showed a high accuracy of surveillance cultures, with pooled sensitivities up to 0.75 and specificities up to 0.92 in culture-positive VAP. The area under the curve (AUC) of the hierarchical summary receiver-operating characteristic curve demonstrates moderate accuracy (AUC: 0.90) in predicting multidrug resistance. A sampling frequency of >2/week (sensitivity 0.79; specificity 0.96) and consideration of only the most recent surveillance culture (sensitivity 0.78; specificity 0.96) are associated with a higher accuracy of prediction.

CONCLUSIONS

This study provides evidence for the benefit of surveillance cultures in predicting MDR bacterial pathogens in VAP. However, clinical and statistical heterogeneity, limited samples sizes, and bias remain important limitations of this meta-analysis.

Critical Care Nurses’ Knowledge of Evidence-Based Guidelines for Preventing Infections Associated With Central Venous Catheters: An Evaluation Questionnaire

Background Lack of adherence to recommended evidence-based guidelines for preventing infections associated with use of central venous catheters may be due to nurses’ lack of knowledge of the guidelines.

Objective To develop a reliable and valid questionnaire for evaluating critical care nurses’ knowledge of evidence-based guidelines for preventing infections associated with central venous catheters.

Methods A total of 10 nursing-related strategies were identified from current evidence-based guidelines for preventing infections associated with use of central venous catheters. Face and content validation were determined for selected interventions and multiple-choice questions (1 question per intervention). The test results of 762 critical care nurses were evaluated for item difficulty, item discrimination, and quality of the response alternatives or options for answers (possible responses).

Results All 10 items had face and content validity. Values for item difficulty ranged from 0.1 to 0.9. Values for item discrimination ranged from 0.05 to 0.41. The quality of the response alternatives (0.0–0.8) indicated widespread misconceptions among the critical care nurses in the sample.

Conclusion The questionnaire is reliable and has face and content validity. Findings from surveys in which this questionnaire is used can lead to better educational programs for critical care nurses on infections associated with use of central venous catheters.

Risk factors and mortality for nosocomial bloodstream infections in elderly patients

OBJECTIVE

To determine risk factors for nosocomial bloodstream infection (BSI) and associated mortality in geriatric patients in geriatric and internal medicine wards at a university hospital.

METHODS

Single-center retrospective (1992-2007), pairwise-matched (1:1-ratio) cohort study. Geriatric patients with nosocomial BSI were matched with controls without BSI on year of admission and length of hospitalization before onset of BSI. Demographic, microbiological, and clinical data are collected.

RESULTS

One-hundred forty-two BSI occurred in 129 patients. Predominant microorganisms were Escherichia coli (23.2%), coagulase-negative Staphylococci (19.4%), Pseudomonas aeruginosa (8.4%), Staphylococcus aureus (7.1%), Klebsiella pneumoniae (5.8%) and Candida spp. (5.8%). Matching was successful for 109 cases. Compared to matched control subjects, cases were more frequently female, suffered more frequently from arthrosis, angina pectoris and pressure ulcers, had worse Activities of Daily Living-scores, had more often an intravenous or bladder catheter, and were more often bedridden. Logistic regression demonstrated presence of an intravenous catheter (odds ratio [OR] 7.5, 95% confidence interval [CI] 2.5-22.9) and being bedridden (OR 2.9, 95% CI 1.6-5.3) as independent risk factors for BSI. In univariate analysis nosocomial BSI was associated with increased mortality (22.0% vs. 11.0%; P=0.029). After adjustment for confounding co-variates, however, nosocomial BSI was not associated with mortality (hazard ratio 1.3, 95% CI 0.6-2.6). Being bedridden and increasing age were independent risk factors for death.

CONCLUSION

Intravenous catheters and being bedridden are the main risk factors for nosocomial BSI. Although associated with higher mortality, this infectious complication seems not to be an independent risk factor for death in geriatric patients.

Pressure injury prevalence and risk factors in Chinese adult intensive care units: A multi-centre prospective point prevalence study

Despite increasing preventive efforts, pressure injury still occurs in intensive care patients. This study was aimed to describe pressure injury prevalence, risk factors, and prevention practices in adult intensive care patients. This was a multi-centre, one-day, prospective point prevalence study in which a total of 198 intensive care units from 21 provinces in China participated. Overall and ICU-acquired prevalence in intensive care patients were 12.26% and 4.31%, respectively. Consistent with earlier reports, almost half of the ICU-acquired pressure injuries were at stage I, one-fourth were at stage 2, and the most common body sites for pressure injuries were sacral and heel region. Risk factors identified were consistent with prior studies. Repositioning was the most commonly used pressure injury prevention strategy, followed by alternating pressure mattresses/overlays, floating heels, and air-filled mattresses/overlays. These reflect a good level of adherence to recommended international pressure injury prevention clinical practice guidelines. The results provide a baseline reference for overall and ICU-acquired prevalence among adult intensive care patients in China. Future research on what contributed to the lower pressure injury incidence in China needs to be conducted to inform healthcare organisations on their future preventive strategies for pressure injury prevention.

Poor timing and failure of source control are risk factors for mortality in critically ill patients with secondary peritonitis

PURPOSE

To describe data on epidemiology, microbiology, clinical characteristics and outcome of adult patients admitted in the intensive care unit (ICU) with secondary peritonitis, with special emphasis on antimicrobial therapy and source control.

METHODS

Post hoc analysis of a multicenter observational study (Abdominal Sepsis Study, AbSeS) including 2621 adult ICU patients with intra-abdominal infection in 306 ICUs from 42 countries. Time-till-source control intervention was calculated as from time of diagnosis and classified into 'emergency' (< 2 h), 'urgent' (2-6 h), and 'delayed' (> 6 h). Relationships were assessed by logistic regression analysis and reported as odds ratios (OR) and 95% confidence interval (CI).

RESULTS

The cohort included 1077 cases of microbiologically confirmed secondary peritonitis. Mortality was 29.7%. The rate of appropriate empiric therapy showed no difference between survivors and non-survivors (66.4% vs. 61.3%, p = 0.1). A stepwise increase in mortality was observed with increasing Sequential Organ Failure Assessment (SOFA) scores (19.6% for a value ≤ 4-55.4% for a value > 12, p < 0.001). The highest odds of death were associated with septic shock (OR 3.08 [1.42-7.00]), late-onset hospital-acquired peritonitis (OR 1.71 [1.16-2.52]) and failed source control evidenced by persistent inflammation at day 7 (OR 5.71 [3.99-8.18]). Compared with 'emergency' source control intervention (< 2 h of diagnosis), 'urgent' source control was the only modifiable covariate associated with lower odds of mortality (OR 0.50 [0.34-0.73]).

CONCLUSION

'Urgent' and successful source control was associated with improved odds of survival. Appropriateness of empirical antimicrobial treatment did not significantly affect survival suggesting that source control is more determinative for outcome.

Nurses' Sedation Practices During Weaning of Adults From Mechanical Ventilation in an Intensive Care Unit

BACKGROUND

Sedation and analgesia have an important impact on the outcome of patients treated with mechanical ventilation. International guidelines recommend use of sedation protocols to ensure best patient care.

OBJECTIVE

To determine the sedation practice of intensive care nurses weaning adults from mechanical ventilation.

METHODS

A cross-sectional survey with a self-administered questionnaire was used to determine sedation practices of Flemish critical care nurses during weaning. Consensus on content validity was achieved through a Delphi procedure among experts. Data were collected during the 32nd Annual Congress of the Flemish Society of Critical Care Nurses in Ghent, Belgium, December 2014.

RESULTS

A total of 342 nurses were included in the study. Of these, 43.7% had a sedation protocol in their unit that was used by 61.8% of the respondents. Sedation protocols were more often available (P < .001) in academic hospitals (72%) than in general hospitals (41.5%). Sedatives were administered via continuous infusion with bolus doses if needed (81%). Level of sedation was assessed every 2 hours (56%), mostly via the Richmond Agitation-Sedation Scale (59.1%). Daily interruption of sedation was used by 16.5% of respondents. The biggest barriers to daily interruption were patient comfort (49.4%) and fear of respiratory worsening (46.6%).

CONCLUSIONS

A considerable discrepancy exists between international recommendations and actual sedation practices. Standardization of sedation practices across different institutions on a regional and national level may improve the quality of care.

Epidemiology and Age-Related Mortality in Critically Ill Patients With Intra-Abdominal Infection or Sepsis: An International Cohort Study

BACKGROUND

The objective of this study is to describe the epidemiology and age-related mortality in older critically ill adults with intra-abdominal infections.

METHODS

This is a secondary analysis of a prospective, multinational, observational study (AbSeS, ClinicalTrials.gov #NCT03270345) including patients with intra-abdominal infection from 309 ICUs in 42 countries (January-December, 2016). Mortality was considered as ICU mortality with a minimum of 28 days of observation when patients were discharged earlier. Relationships with mortality were assessed by logistic regression analysis.

RESULTS

The cohort included 2337 patients. Four age groups were defined: middle-aged patients as reference category (40-59 years; n=659 [28.2%]), young-old (60-69 years; n=622 [26.6%]), middle-old (70-79 years; n=667 [28.5%]) and very-old patients (≥80 years; n=389 [16.6%]). Secondary peritonitis was the predominant infection (68.7%) and equally prevalent across age groups. Mortality increased with age: 20.9% in middle-aged patients, 30.5% in young-old, 31.2% in middle-old, and 44.7% in very-old patients (p<0.001). Compared to middle-aged patients, young-old age (OR 1.62, 95% CI 1.21-2.17), middle-old age (OR 1.80, 95% CI 1.35-2.41), and very-old age (OR 3.69, 95% CI 2.66-5.12) were independently associated with mortality. Other independent risk factors for mortality included late-onset hospital-acquired intra-abdominal infection, diffuse peritonitis, sepsis/septic shock, source control failure, liver disease, congestive heart failure, diabetes, and malnutrition.

CONCLUSIONS

For ICU patients with intra-abdominal infections, age above 60 years was associated with mortality while patients above 80 years had the worst prognosis. Comorbidities and overall disease severity further compromised survival. As all these factors are non-modifiable it remains unclear how to improve outcomes.

Pressure injury prevalence in Australian intensive care units: A secondary analysis

BACKGROUND

Pressure injuries (PIs) are an enduring problem for patients in the intensive care unit (ICU) because of their vulnerability and numerous risk factors.

METHOD

This study reports Australian data as a subset of data from an international 1-day point prevalence study of ICU-acquired PI in adult patients. Patients aged 18 years or older and admitted to the ICU on the study day were included. The outcome measure was the identification of a PI by direct visual skin assessment on the study day. Data collected included demographic data and clinical risk factors, PI location and stage, and PI prevention strategies used. Descriptive statistics were used to describe PI characteristics, and odds ratios (ORs) were used to identify factors associated with the development of a PI.

RESULTS

Data were collected from 288 patients from 16 Australian ICUs. ICU-acquired PI prevalence was 9.7%, with 40 PIs identified on 28 patients. Most PIs were of stage 1 and stage 2 (26/40, 65.0%). Half of the ICU-acquired PIs were found on the head and face. The odds of developing an ICU-acquired PI increased significantly with renal replacement therapy (OR: 4.25, 95% confidence interval [CI]: 1.49-12.11), impaired mobility (OR: 3.13, 95% CI: 1.08-9.12), fastest respiratory rate (OR: 1.05 [per breath per minute], 95% CI: 1.00-1.10), longer stay in the ICU (OR: 1.04 [per day], 95% CI: 1.01-1.06), and mechanical ventilation on admission (OR: 0.36, CI: 0.14-0.91).

CONCLUSION

This study found that Australian ICU-acquired PI prevalence was 9.7% and these PIs were associated with many risk factors. Targeted PI prevention strategies should be incorporated into routine prevention approaches to reduce the burden of PIs in the Australian adult ICU patient population.

Insights and advances in multidisciplinary critical care: a review of recent research

The intensive care unit is a work environment where superior dedication is pivotal to optimize patients' outcomes. As this demanding commitment is multidisciplinary in nature, it requires special qualities of health care workers and organizations. Thus research in the field covers a broad spectrum of activities necessary to deliver cutting-edge care. However, given the abundance of research articles and education activities available, it is difficult for modern critical care clinicians to keep up with the latest progress and innovations in the field. This article broadly summarizes new developments in multidisciplinary intensive care, providing elementary information about advanced insights in the field by briefly describing selected articles bundled in specific topics. Issues considered include cardiovascular care, monitoring, mechanical ventilation, infection and sepsis, nutrition, education, patient safety, pain assessment and control, delirium, mental health, ethics, and outcomes research.

Gastric residual volume measurement in the intensive care unit: an international survey reporting nursing practice

BACKGROUND

Gastric residual volume measurement is routinely used to evaluate the feeding tolerance and gastro-oesophageal reflux in patients receiving enteral feeding therapy in the intensive care unit. However, little supportive evidence for this intervention is available as the usefulness of gastric residual volume measurements in patients receiving enteral feeding therapy in the intensive care is controversial.

AIM

The aim of this study was to assess the practice of intensive care unit nurses related to gastric residual volume measurement in patients receiving enteral nutrition.

METHODS

A survey was conducted among a sample of intensive care unit nurses (n = 832) from four hospitals in Turkey (n = 182) and attendees of the Annual Congress of the Flemish Society for Critical Care Nurses in Flanders, Belgium (n = 650). The survey instrument was developed by the researchers based on the related literature.

RESULTS

A total of 480 nurses completed the questionnaire (response rate = 73%). Gastric residual volume is measured by 98·0% of respondents, with wide variations in the frequency of measuring. A 50-200 mL gastric residual volume is considered problematic by 45·5% (n = 183) of the participants, and only 18·4% (n = 81) reported their practice to be based on a current guideline. Strikingly, more experienced intensive care unit nurses appear to perform gastric residual volume measurements more commonly than their less experienced colleagues (p = 0·004), while the practice is more often reported to be performed in Belgium than in Turkey (p < 0·001).

CONCLUSION

Gastric residual volume management could be improved by applying current evidence to daily nursing practice.

RELEVANCE TO CLINICAL PRACTICE

Our results show that increased awareness of these guidelines by nurses is needed to reduce inefficient use of working time and resources, streamline clinical practices and improve patient outcomes. Current gastric residual volume measurement guidelines and up-to-date, relevant training should be provided to nurses.

Recent advances in multidisciplinary critical care

The intensive care unit is a work environment where superior dedication is crucial for optimizing patients' outcomes. As this demanding commitment is multidisciplinary in nature, it requires special qualities of health care workers and organizations. Thus research in the field covers a broad spectrum of activities necessary to deliver cutting-edge care. However, given the numerous research articles and education activities available, it is difficult for modern critical care clinicians to keep up with the latest progress and innovation in the field. This article broadly summarizes new developments in multidisciplinary intensive care. It provides elementary information about advanced insights in the field via brief descriptions of selected articles grouped by specific topics. Issues considered include care for heart patients, mechanical ventilation, delirium, nutrition, pressure ulcers, early mobility, infection prevention, transplantation and organ donation, care for caregivers, and family matters.