A complete and multifaceted overview of antibiotic use and infection diagnosis in the intensive care unit: results from a prospective four-year registration

Performance and impact of rapid multiplex PCR on diagnosis and treatment of ventilated hospital-acquired pneumonia in patients with extended-spectrum β-lactamase-producing Enterobacterales rectal carriage

BACKGROUND

Antimicrobial stewardship (AMS) for ventilator-associated pneumonia (VAP) or ventilated hospital-acquired pneumonia (vHAP) in extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) carriers is challenging. BioFire® FilmArray® Pneumonia plus Panel (mPCR) can detect bacteria and antibiotic resistance genes, including blaCTX-M, the most common ESBL-encoding gene.

METHODS

This monocentric, prospective study was conducted on a group of ESBL-E carriers from March 2020 to August 2022. The primary objective was to evaluate the concordance between the results of mPCR and conventional culture performed on respiratory samples of ESBL-E carriers to investigate suspected VAP/vHAP. The secondary objective was to appraise the impact of performing or not mPCR on initial antibiotic therapy adequacy in ESBL-E carriers with confirmed VAP/vHAP.

RESULTS

Over the study period, 294 patients with ESBL-E carriage were admitted to the ICU, of who 168 (57%) were mechanically ventilated. (i) Diagnostic performance of mPCR was evaluated in suspected 41 episodes of VAP/vHAP: blaCTX-M gene was detected in 15/41 (37%) episodes, where 9/15 (60%) were confirmed ESBL-E-induced pneumonia. The culture and blaCTX-M were concordant in 35/41 (85%) episodes, and in all episodes where blaCTX-M was negative (n = 26), the culture never detected ESBL-E. (ii) The impact of mPCR on initial antibiotic therapy adequacy was assessed in 95 episodes of confirmed VAP/vHAP (22 episodes were tested with mPCR and 73 without); 47 (49%) episodes were ESBL-E-induced, and 24 (25%) were carbapenem-resistant bacteria-induced. The use of mPCR was significantly associated with higher prescription of adequate empirical antibiotic therapy in the multivariable logistic regression (adjusted odds ratio (aOR) (95% CI) of 7.5 (2.1-35.9), p = 0.004), propensity-weighting (aOR of 5.9 (1.6-22.1), p = 0.008), and matching-cohort models (aOR of 5.8 (1.5-22.1), p = 0.01).

CONCLUSION

mPCR blaCTX-M showed an excellent diagnostic value to rule out the diagnosis of ESBL-E related pneumonia in ESBL-E carriers with suspected VAP/vHAP. In addition, in patients with confirmed VAP/vHAP, a mPCR-based antibiotic therapy was associated with an increased prescription of adequate empirical antibiotic therapy. Performing mPCR on respiratory samples seems to be a promising tool in ESBL-E carriers with suspected vHAP/VAP. However, if mPCR is used in very low pre-test clinical probability of pneumonia, due to the high sensitivity and the rate of overdiagnosed pneumonia, the risk of overconsumption of carbapenem may prevail. Further studies are warranted.

Automated surveillance of antimicrobial consumption in intensive care, northern Sweden: an observational case study

BACKGROUND

The digitalization of information systems allows automatic measurement of antimicrobial consumption (AMC), helping address antibiotic resistance from inappropriate drug use without compromising patient safety.

OBJECTIVES

Describe and characterize a new automated AMC surveillance service for intensive care units (ICUs), with data stratified by referral clinic and linked with individual patient risk factors, disease severity, and mortality.

METHODS

An automated service collecting data from the electronic medical record was developed, implemented, and validated in a healthcare region in northern Sweden. We performed an observational study from January 1, 2018, to December 31, 2021, encompassing general ICU care for all ≥18-years-olds in a catchment population of 270000 in secondary care and 900000 in tertiary care. We used descriptive analyses to associate ICU population characteristics with AMC outcomes over time, including days of therapy (DOT), length of therapy, defined daily doses, and mortality.

RESULTS

There were 5608 admissions among 5190 patients with a median age of 65 (IQR 48-75) years, 41.2% females. The 30-day mortality was 18.3%. Total AMC was 1177 DOTs in secondary and 1261 DOTs per 1000 patient days and tertiary care. AMC varied significantly among referral clinics, with the highest total among 810 general surgery admissions in tertiary care at 1486 DOTs per 1000 patient days. Case-mix effects on the AMC were apparent during COVID-19 waves highlighting the need to account for case-mix. Patients exposed to more than three antimicrobial drug classes (N = 242) had a 30-day mortality rate of 40.6%, with significant variability in their expected rates based on admission scores.

CONCLUSION

We introduce a new service and instructions for automating local ICU-AMC data collection. The versatile long-term ICU-AMC metrics presented, covering patient factors, referral clinics and mortality outcomes, are expected to be beneficial in refining antimicrobial drug use.

The use of information technology to improve interdisciplinary communication during infectious diseases ward rounds on the paediatric intensive care unit

Prospective audit with feedback during infectious diseases ward rounds (IDWR) is a common antimicrobial stewardship (AMS) practice on the Paediatric Intensive Care Unit (PICU). These interdisciplinary meetings rely on the quality of handover, with high risk of omission of information. We developed an electronic platform integrating infection-related patient data (COSARAPed). In the mixed PICU of a Belgian tertiary hospital we conducted an observational prospective cohort study comparing patient handovers during IDWRs using the COSARAPed-platform to those with access only to conventional resources. The quality of handover was investigated directly by assessment if the narrative was in accordance with Situation-Background-Assessment-Recommendation principles and if adequate demonstration of diagnostic information occurred, and also indirectly by registration if this was only achieved after intervention by the non-presenting AMS team members. We also recorded all AMS-recommendations. During a 6-month study period, 24 IDWRs and 82 patient presentations were assessed. We could only find a statistically significant advantage in favor of COSARAPed by indirect evaluation. We registered 92 AMS-recommendations, mainly resulting in reduced antibiotic pressure. We concluded that the IDWR is an appropriate platform for AMS on the PICU and that the utilisation of COSARAPed may enhance the quality of patient handover.

Drug Utilization Research and Predictors of Outcomes in the Intensive Care Unit of a Tertiary Care Hospital: A Prospective Observational Study

BACKGROUND

Multiple drugs are commonly prescribed to intensive care unit (ICU) patients owing to the disease profile, multiple organ dysfunction, prophylaxis, management of stress ulcers, nosocomial infections, etc. This study aimed to evaluate the drug utilization patterns and factors influencing mortality and duration of stay in ICU patients.  Methodology: A prospective observational study was conducted in the ICU of our tertiary care hospital, Postgraduate Institute of Medical Sciences, Rohtak. Data was collected from treatment charts of patients using a structured pretested proforma. World Health Organization Anatomical Therapeutic Chemical/Defined Daily Dose (WHO ATC/DDD) methodology and core prescribing indicators were used to assess drug utilization data. The effect of different variables on mortality and duration of stay in the ICU was evaluated using regression analysis.

RESULTS

An average of 8.78 drugs were prescribed per patient. Among the 922 prescriptions, anti-infectives, anti-inflammatory drugs, and drugs acting on the gastrointestinal tract were the most frequent medication classes prescribed. Polypharmacy and trade name prescribing were common. For most of the drugs, the prescribed daily dose corresponded to the WHO-DDD except ceftriaxone and levofloxacin. Age, presence of cardiac disorders, and Glasgow Coma Scale (GCS) score at admission directly correlated with mortality while the use of diuretics had a negative correlation with the duration of ICU stay.  Conclusions: There is a need to rationalize drug therapy in the ICU with regard to limiting polypharmacy and emphasizing generic drug name prescribing and adherence to the essential drug list. Antibiotic prescription patterns, in particular, deserve a special focus keeping in mind the multitude of factors demanding aggressive antibiotic use in critically ill intensive care patients.

Pathogen-based target attainment of optimized continuous infusion dosing regimens of piperacillin-tazobactam and meropenem in surgical ICU patients: a prospective single center observational study

BACKGROUND

Several studies have indicated that commonly used piperacillin-tazobactam (TZP) and meropenem (MEM) dosing regimens lead to suboptimal plasma concentrations for a range of pharmacokinetic/pharmacodynamic (PK/PD) targets in intensive care unit (ICU) patients. These targets are often based on a hypothetical worst-case scenario, possibly overestimating the percentage of suboptimal concentrations. We aimed to evaluate the pathogen-based clinically relevant target attainment (CRTA) and therapeutic range attainment (TRA) of optimized continuous infusion dosing regimens of TZP and MEM in surgical ICU patients.

METHODS

A single center prospective observational study was conducted between March 2016 and April 2019. Free plasma concentrations were calculated by correcting total plasma concentrations, determined on remnants of blood gas samples by ultra-performance liquid chromatography with tandem mass spectrometry, for their protein binding. Break points (BP) of identified pathogens were derived from epidemiological cut-off values. CRTA was defined as a corrected measured total serum concentration above the BP and calculated for increasing BP multiplications up to 6 × BP. The upper limit of the therapeutic range was set at 157.2 mg/L for TZP and 45 mg/L for MEM. As a worst-case scenario, a BP of 16 mg/L for TZP and 2 mg/L for MEM was used.

RESULTS

781 unique patients were included with 1036 distinctive beta-lactam antimicrobial prescriptions (731 TZP, 305 MEM) for 1003 unique infections/prophylactic regimens (750 TZP, 323 MEM). 2810 samples were available (1892 TZP, 918 MEM). The median corrected plasma concentration for TZP was 86.4 mg/L [IQR 56.2-148] and 16.2 mg/L [10.2-25.5] for MEM. CRTA and TRA was consistently higher for the pathogen-based scenario than for the worst-case scenario, but nonetheless, a substantial proportion of samples did not attain commonly used PK/PD targets.

CONCLUSION

Despite these pathogen-based data demonstrating that CRTA and TRA is higher than in the often-used theoretical worst-case scenario, a substantial proportion of samples did not attain commonly used PK/PD targets when using optimised continuous infusion dosing regimens. Therefore, more dosing optimization research seems warranted. At the same time, a 'pathogen-based analysis' approach might prove to be more sensible than a worst-case scenario approach when evaluating target attainment and linked clinical outcomes.

Individualised antimicrobial dose optimisation: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Therapeutic drug management (TDM) and model-informed precision dosing (MIPD) allow dose individualisation to increase drug effectivity and reduce toxicity.

OBJECTIVES

Evaluate the available evidence on the clinical efficacy of individualised antimicrobial dosing optimisation.

METHODS

Data sources: Pubmed, Embase, Web of Science, and Cochrane Library databases from database inception to the 11th of November 2022.

STUDY ELIGIBILITY CRITERIA

Published peer-reviewed Randomised Controlled Trials (RCTs).

PARTICIPANTS

Human subjects aged ≥18 years receiving an antibiotic or antifungal drug.

INTERVENTIONS

Patients receiving individualised antimicrobial dose adjustment. Assessment of risk of bias: Cochrane risk-of-bias tool for randomised trials (RoB2). Methods of data synthesis: Primary outcome was the risk of mortality. Secondary outcomes included target attainment, treatment failure, clinical and microbiological cure, length of stay, treatment duration and adverse events. Effect sizes were pooled using a random-effects model. Statistical heterogeneity was assessed by inconsistency testing (I²).

RESULTS

Ten RCTs were included in the meta-analysis (1,241 participants; n= 624 in the TDM group, n = 617 in the control group). Individualised antimicrobial dose optimisation was associated with a numerical decrease in mortality (RR = 0.86; 95% CI 0.71-1.05), without reaching statistical significance. Moreover, it was associated with significantly higher target attainment rates (RR = 1.41; 95% CI, 1.13-1.76) and a significant decrease in treatment failure (RR = 0.70; 95% CI, 0.54-0.92). Individualised antimicrobial dose optimisation was also associated with improvement, but not significant in clinical cure (RR = 1.33; 95% CI, 0.94-1.33) and microbiological outcome (RR = 1.25; CI, 1.00-1.57), as well as with a significant decrease in the risk of nephrotoxicity (RR = 0.55; 95% CI, 0.31-0.97).

CONCLUSIONS

This meta-analysis demonstrates that target attainment, treatment failure, and nephrotoxicity were significantly improved in patients who underwent individualised antimicrobial dose optimisation. However, it did not show a significant decrease in mortality, clinical cure or microbiological outcome.

Antibiotics use evaluation among hospitalized adult patients at Jimma Medical Center, southwestern Ethiopia: the way to pave for antimicrobial stewardship

BACKGROUND

An irrational antibiotic use is a common problem in developing countries like Ethiopia, which makes empiric antibiotics use difficult. It is considered to be the greatest health problem in our time and future unless intervened. Therefore, this study aimed to assess the patterns of antibiotics use among hospitalized adult patients to pave the way for antimicrobial stewardship.

METHODS

A hospital-based prospective observational study was conducted at Jimma Medical Center, southwestern Ethiopia, from 30 October 2020 to 29 January 2021 with 360 adult hospitalized patients participating. A semi-structured questionnaire and consecutive sampling technique was used for data collection. The data were collected through medical record reviews and patient interviews. The collected data were entered into Epi-data and exported to SPSS® version 23.0 for analysis. Days of therapy (DOT) and essential medicine lists "Access, Watch, and Reserve (AWaRe)" antibiotics classification were used to assess antibiotic use pattern among participants.

RESULTS

The majority of study participants were females (55.3%), attended formal education (59.4%), and live in rural areas (61.4%) with mean age ± (SD) of 37.65 ± (16.75). The overall rate of antibiotics consumption during the study was 111 days of therapy per 100 bed-days and about two-thirds (66%) of the prescribed antibiotics were from the "Watch" group antibiotics. The indicator level of antibiotics use for "Access" group antibiotics was 34% in this study based on the World Health Organization Essential Medicine List. Cephalosporins were the most commonly used class of antibiotics (93.9%).

CONCLUSION

Higher antibiotics exposure and their consumption frequently observed among adult hospitalized patients in the study setting. There was a rapid increase in "Watch" group antibiotics use and about two-thirds of the prescribed antibiotics were from this group. The third-generation cephalosporin were the most commonly used class of antibiotics. Generally, higher consumption and inappropriate antibiotics use among hospitalized adult patients showed the need for urgent interventions by implementing Antimicrobial Stewardship Programs in hospitals.

Characteristics of Sepsis-2 septic shock patients failing to satisfy the Sepsis-3 septic shock definition: an analysis of real-time collected data

BACKGROUND

Baseline characteristics and disease severity of patients with septic shock according to the new Sepsis-3 definition may differ from patients that only comply with the Sepsis-2 definition. We conducted a retrospective cohort study on the ICU of a Belgian tertiary care facility to seek out differences between these two patient groups and to identify variables associated with no longer satisfying the latest definition of septic shock.

RESULTS

Of 1198 patients with septic shock according to the Sepsis-2 consensus definition, 233 (19.4%) did not have septic shock according to the Sepsis-3 shock definition. These patients more often had medical admission reasons and a respiratory infection as cause for the septic shock. They less often had surgery on admission and were less likely to have chronic liver disease (5.6% vs 16.2%, absolute difference 10.6% (95% CI 6.4-14.1%). Patients with septic shock only according to the old definition had significant lower APACHE II and SOFA scores and lower hospital mortality (31.6% vs 55.3%, p < 0.001). In a multivariate analysis, following variables were associated with Sepsis-2 shock patients no longer being defined as such by the Sepsis-3 definition: respiratory infection (OR 1.485 (95% CI 1.56-2.089), p = 0.023), a medical admission reason (OR 1.977 (95% CI 1.396-2.800) and chronic liver disease (OR 0.345 (95% CI 0.181-0.660), p < 0.001).

CONCLUSIONS

One in five patients with septic shock according to the Sepsis-2 consensus definition is no longer considered as such when the Sepsis-3 shock criteria are applied. A medical admission reason, a respiratory infection and absence of chronic liver disease are independently associated with no longer being identified as having septic shock by the Sepsis-3 criteria.

The Utility of Bedside Assessment Tools and Associated Factors to Avoid Antibiotic Overuse in an Urban PICU of a Diarrheal Disease Hospital in Bangladesh

BACKGROUND

Antibiotic exposure in the pediatric intensive care unit (PICU) is very high, although 50% of all antibiotics may be unnecessary. We aimed to determine the utility of simple bedside screening tools and predicting factors to avoid antibiotic overuse in the ICU among children with diarrhea and critical illness.

METHODS

We conducted a retrospective, single-center, case-control study that included children aged 2-59 months who were admitted to PICU with diarrhea and critical illness between 2017 and 2020.

RESULTS

We compared young children who did not receive antibiotics (cases, n = 164) during ICU stay to those treated with antibiotics (controls, n = 346). For predicting the 'no antibiotic approach', the sensitivity of a negative quick Sequential Organ Failure Assessment (qSOFA) was similar to quick Pediatric Logistic Organ Dysfunction-2 (qPELOD-2) and higher than Systemic Inflammatory Response Syndrome (SIRS). A negative qSOFA or qPELOD-2 score calculated during PICU admission is superior to SIRS to avoid antibiotic overuse in under-five children. The logistic regression analysis revealed that cases were more often older and independently associated with hypernatremia. Cases less often had severe underweight, altered mentation, age-specific fast breathing, lower chest wall in-drawing, adventitious sound on lung auscultation, abdominal distension, developmental delay, hyponatremia, hypocalcemia, and microscopic evidence of invasive diarrhea (for all, p < 0.05).

CONCLUSION

Antibiotic overuse could be evaded in PICU using simple bedside screening tools and clinical characteristics, particularly in poor resource settings among children with diarrhea.

Antibiotic utilization, sensitivity, and cost in the medical intensive care unit of a tertiary care teaching hospital in Nepal

Background:

High utilization and irrational use of antibiotics in an intensive care unit increases microbial resistance, morbidity, mortality, and costs.

Objective:

This study aimed to evaluate the utilization, sensitivity and cost analysis of antibiotics used in the medical intensive care unit of a tertiary care teaching hospital of Nepal.

Methods:

A prospective cohort study was conducted on patients admitted to the medical intensive care unit at a tertiary care teaching hospital in central Nepal from July to September 2016. Antibiotic utilization, defined daily dose per 100 bed-days and the cost of antibiotics per patient were calculated. Descriptive statistics were performed using IBM-SPSS 20.0.

Results:

A total of 365 antibiotics were prescribed in 157 patients during the study period, with an average of 2.34 prescriptions per patient. Total antibiotic utilization in terms of defined daily dose per 100 bed-days was 49.5. Piperacillin/tazobactam (45.2%) was the most commonly prescribed antibiotic, and meropenem was the most expensive antibiotics (US$4440.70). The median (interquartile range) cost of antibiotics used per patient was US$47.67 (US$63.73). Escherichia coli, Acinetobacter, and Pseudomonas sp. were the common organisms isolated and were found to be resistant to some of the commonly used antibiotics.

Conclusion:

This study suggests that the utilization and cost of antibiotics are high in medical intensive care unit of the hospital and E. coli was resistant to multiple antibiotics. The findings highlight an urgent need for the implementation of antibiotic stewardship program in order to improve antibiotic utilization in such hospital settings.

Attributable Mortality of Ventilator-associated Pneumonia. Replicating Findings, Revisiting Methods

Rationale: Estimating the impact of ventilator-associated pneumonia (VAP) from routinely collected intensive care unit (ICU) data is methodologically challenging.

Objectives: We aim to replicate earlier findings of limited VAP-attributable ICU mortality in an independent cohort. By refining statistical analyses, we gradually tackle different sources of bias.

Methods: Records of 2,720 adult patients admitted to Ghent University Hospital ICUs (2013–2017) and receiving mechanical ventilation within 48 hours after admission were extracted from linked Intensive Care Information System and Computer-based Surveillance and Alerting of Nosocomial Infections, Antimicrobial Resistance, and Antibiotic Consumption in the ICU databases. The VAP-attributable fraction of ICU mortality was estimated using a competing risk analysis that is restricted to VAP-free patients (approach 1), accounts for VAP onset by treating it as either a competing (approach 2) or censoring event (approach 3), or additionally adjusts for time-dependent confounding via inverse probability weighting (approach 4).

Results: A total of 210 patients (7.7%) acquired VAP. Based on benchmark approach 4, we estimated that (compared with current preventive measures) hypothetical eradication of VAP would lead to a relative ICU mortality reduction of 1.7% (95% confidence interval, −1.3 to 4.6) by Day 10 and of 3.6% (95% confidence interval, 0.7 to 6.5) by Day 60. Approaches 1–3 produced estimates ranging from −0.7% to 2.5% by Day 10 and from 5.2% to 5.5% by Day 60.

Conclusions: In line with previous studies using appropriate methodology, we found limited VAP-attributable ICU mortality given current state-of-the-art VAP prevention measures. Our study illustrates that inappropriate accounting of the time dependency of exposure and confounding of its effects may misleadingly suggest protective effects of early-onset VAP and systematically overestimate attributable mortality.

A mandatory indication-registration tool in hospital electronic medical records enabling systematic evaluation and benchmarking of the quality of antimicrobial use: a feasibility study

Objectives

Evaluation of the extent and appropriateness of antimicrobial use is a cornerstone of antibiotic stewardship programs, but it is time-consuming. Documentation of the indication at the moment of prescription might be more time-efficient. We investigated the real-life feasibility of mandatory documentation of the indication for all hospital antibiotic prescriptions for quality evaluation purposes.

Methods

A mandatory prescription-indication format was implemented in the Electronic Medical Record (EMR) of three hospitals using EPIC or ChipSoft HIX software. We evaluated the retrieved data of all antibiotics (J01) prescribed as empiric therapy in adult patients with respiratory tract infections (RTI) or urinary tract infections (UTI), from January through December 2017 in Hospital A, June through October 2019 in Hospital B and May 2019 through June 2020 in Hospital C. Endpoints were the accuracy of the data, defined as agreement between selected indication for the prescription and the documented indication in the EMR, as assessed by manually screening a representative sample of eligible patient records in the EMR of the three hospitals, and appropriateness of the prescriptions, defined as the prescriptions being in accordance with the national guidelines.

Results

The datasets of hospitals A, B and C contained 9588, 338 and 5816 empiric antibiotic prescriptions indicated for RTI or UTI, respectively. The selected indication was in accordance with the documented indication in 96.7% (error rate: 10/300), 78.2% (error rate: 53/243), and 86.9% (error rate: 39/298), respectively. A considerable variation in guideline adherence was seen between the hospitals for severe community acquired pneumonia (adherence rate ranged from 35.4 to 53.0%), complicated UTI (40.0–67.1%) and cystitis (5.6–45.3%).

Conclusions

After local validation of the datasets to verify and optimize accuracy of the data, mandatory documentation of the indication for antibiotics enables a reliable and time-efficient method for systematic registration of the extent and appropriateness of empiric antimicrobial use, which might enable benchmarking both in-hospital and between hospitals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-021-00973-0.

Systematic review of studies investigating ventilator associated pneumonia diagnostics in intensive care

Background

Ventilator-associated pneumonia (VAP) is an important diagnosis in critical care. VAP research is complicated by the lack of agreed diagnostic criteria and reference standard test criteria. Our aim was to review which reference standard tests are used to evaluate novel index tests for suspected VAP.

Methods

We conducted a comprehensive search using electronic databases and hand reference checks. The Cochrane Library, MEDLINE, CINHAL, EMBASE, and web of science were searched from 2008 until November 2018. All terms related to VAP diagnostics in the intensive treatment unit were used to conduct the search. We adopted a checklist from the critical appraisal skills programme checklist for diagnostic studies to assess the quality of the included studies.

Results

We identified 2441 records, of which 178 were selected for full-text review. Following methodological examination and quality assessment, 44 studies were included in narrative data synthesis. Thirty-two (72.7%) studies utilised a sole microbiological reference standard; the remaining 12 studies utilised a composite reference standard, nine of which included a mandatory microbiological criterion. Histopathological criteria were optional in four studies but mandatory in none.

Conclusions

Nearly all reference standards for VAP used in diagnostic test research required some microbiological confirmation of infection, with BAL culture being the most common reference standard used.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01560-0.

Strategies for implementation of a multidisciplinary approach to the treatment of nosocomial infections in critically ill patients

INTRODUCTION

Intensive Care Units (ICU) are among the hospital wards exhibiting the highest prevalence of antimicrobial resistance (AMR), and resulting impact on patient outcomes. Antimicrobial resistance surveillance and antimicrobial stewardship (AMS) programs play a pivotal role in promoting interventions tailored to optimize infection diagnosis and treatment in the final attempt to limit unnecessary antimicrobial use and development of resistance.

AREAS COVERED

A narrative review of the literature was carried out to summarize the available evidence and develop a set of actions that should be considered for integration into the ICU stewardship framework. Four questions were addressed: how AMR surveillance can inform antibiotic policy in ICU; whether pharmacokinetic and pharmacodynamic (PK/PD) principles and the use of procalcitonin should be incorporated as a standard practice in ICU AMS programs to optimize antibiotic treatment and to drive antibiotic discontinuation; which criteria should drive treatment duration of ICU-associated infections.

EXPERT OPINION

In this review we aim to highlight that the ICU must be considered in its own right. Each ICU has its own characteristics depending on the country, on the local antibiotic resistance profile, on the patients feature and the severity of infection.

Variation in antibiotic use across intensive care units (ICU): A population-based cohort study in Ontario, Canada

OBJECTIVES

Antibiotics are commonly used in intensive care units (ICUs), yet differences in antibiotic use across ICUs are unknown. Herein, we studied antibiotic use across ICUs and examined factors that contributed to variation.

METHODS

We conducted a retrospective cohort study using data from Ontario's Critical Care Information System (CCIS), which included 201 adult ICUs and 2,013,397 patient days from January 2012 to June 2016. Antibiotic use was measured in days of therapy (DOT) per 1,000 patient days. ICU factors included ability to provide ventilator support (level 3) or not (level 2), ICU type (medical-surgical or other), and academic status. Patient factors included severity of illness using multiple-organ dysfunction score (MODS), ventilatory support, and central venous catheter (CVC) use. We analyzed the effect of these factors on variation in antibiotic use.

RESULTS

Overall, 269,351 patients (56%) received antibiotics during their ICU stay. The mean antibiotic use was 624 (range 3-1460) DOT per 1,000 patient days. Antibiotic use was significantly higher in medical-surgical ICUs compared to other ICUs (697 vs 410 DOT per 1,000 patient days; P < .0001) and in level 3 ICUs compared to level 2 ICUs (751 vs 513 DOT per 1,000 patient days; P < .0001). Higher antibiotic use was associated with higher severity of illness and intensity of treatment. ICU and patient factors explained 47% of the variation in antibiotic use across ICUs.

CONCLUSIONS

Antibiotic use varies widely across ICUs, which is partially associated with ICUs and patient characteristics. These differences highlight the importance of antimicrobial stewardship to ensure appropriate use of antibiotics in ICU patients.

Impact of the Beta-Glucan Test on Management of Intensive Care Unit Patients at Risk for Invasive Candidiasis

The 1,3-beta-d-glucan (BDG) test is used for the diagnosis of invasive candidiasis (IC) in intensive care units (ICUs). However, its utility for patient management is unclear. This study assessed the impact of BDG test results on therapeutic decisions. This was a single-center observational study conducted in an ICU over two 6-month periods. All BDG test requests for the diagnosis of IC were analyzed. Before the second period, the ICU physicians received a pocket card instruction (algorithm) for targeted BDG testing in high-risk patients. The performance of the BDG test for IC diagnosis was assessed, as well as its impact on antifungal (AF) prescription. Overall, 72 patients had ≥1 BDG test, and 14 (19%) patients had an IC diagnosis. The BDG test results influenced therapeutic decisions in 41 (57%) cases. The impact of the BDG test was positive in 30 (73%) of them, as follows: AF abstention/interruption following a negative BDG result (n = 27), and AF initiation/continuation triggered by a positive BDG test result and subsequently confirmed IC (n = 3). In 10 (24%) cases, a positive BDG test result resulted in AF initiation/continuation with no further evidence of IC. A negative BDG result and AF abstention with subsequent IC diagnosis were observed in one case. The positive predictive value (PPV) of BDG was improved if testing was restricted to the algorithm's indications (80% versus 36%, respectively). However, adherence to the algorithm was low (26%), and no benefit of the intervention was observed. The BDG result had an impact on therapeutic decisions in more than half of the cases, which consisted mainly of safe AF interruption/abstention. Targeted BDG testing in high-risk patients improves PPV but is difficult to achieve in ICU.

Optimal and responsible use of antibiotics

PURPOSE OF REVIEW

In this review, we focus on the dual face of antibiotic therapy in the critically ill that must harmonize the need for early, appropriate and adequate antibiotic therapy in the individual-infected patient with the obligation to limit antibiotic selection pressure as much as possible to preserve its future potential.

RECENT FINDINGS

Recent articles have highlighted and detailed the various aspects, which determine antibiotic efficacy, and have identified adjunctive treatments, such as source control, which impact outcome. In addition, settings and indications where antibiotics do not improve outcome and may cause harm have been identified.

SUMMARY

Reconciling antibiotic efficacy with the limitations of their use is feasible but requires a dedicated and sustained effort throughout the whole process of clinical decision-making, from initial suspicion of sepsis to its definitive treatment.

Pharmacokinetic and Pharmacodynamic Characteristics of Vancomycin and Meropenem in Critically Ill Patients Receiving Sustained Low-efficiency Dialysis

PURPOSE

Antibiotic dosing is challenge in critically ill patients undergoing renal replacement therapy. Our aim was to evaluate the pharmacokinetic and pharmacodynamic (PK/PD) characteristics of meropenem and vancomycin in patients undergoing SLED.

METHODS

Consecutive ICU patients undergoing SLED and receiving meropenem and/or vancomycin were prospectively evaluated. Serial blood samples were collected before, during, and at the end of SLED sessions. Antimicrobial concentrations were determined using a validated HPLC method. Noncompartmental PK analysis was performed. AUC was determined for vancomycin. For meropenem, time above MIC was calculated.

FINDINGS

A total of 24 patients receiving vancomycin and 21 receiving meropenem were included; 170 plasma samples were obtained. Median serum vancomycin and meropenem concentrations before SLED were 24.5 and 28.0 μg/mL, respectively; after SLED, 14 and 6 μg/mL. Mean removal was 42% with vancomycin and 78% with meropenem. With vancomycin, 19 (83%), 16 (70%), and 15 (65%) patients would have achieved the target (AUC_0-24 >400) considering MICs of 1, 2, and 4 mg/L, respectively. With meropenem, 17 (85%), 14 (70%), and 10 (50%) patients would have achieved the target (100% of time above MIC) if infected with isolates with MICs of 1, 4, and 8 mg/L, respectively.

IMPLICATIONS

SLED clearances of meropenem and vancomycin were 3-fold higher than the clearance described by continuous methods. Despite this finding, overall high PK/PD target attainments were obtained, except for at higher MICs. We suggest a maintenance dose of 1 g TID or BID of meropenem. With vancomycin, a more individualized approach using therapeutic drug monitoring should be used, as commercial assays are available.

Automated screening of natural language in electronic health records for the diagnosis septic shock is feasible and outperforms an approach based on explicit administrative codes

PURPOSE

Identification of patients for epidemiologic research through administrative coding has important limitations. We investigated the feasibility of a search based on natural language processing (NLP) on the text sections of electronic health records for identification of patients with septic shock.

MATERIALS AND METHODS

Results of an explicit search strategy (using explicit concept retrieval) and a combined search strategy (using both explicit and implicit concept retrieval) were compared to hospital ICD-9 based administrative coding and to our department's own prospectively compiled infection database.

RESULTS

Of 8911 patients admitted to the medical or surgical ICU, 1023 (11.5%) suffered from septic shock according to the combined search strategy. This was significantly more than those identified by the explicit strategy (518, 5.8%), by hospital administrative coding (549, 5.8%) or by our own prospectively compiled database (609, 6.8%) (p < .001). Sensitivity and specificity of the automated combined search strategy were 72.7% (95%CI 69.0%-76.2%) and 93.0% (95%CI 92.4%-93.6%), compared to 56.0% (95%CI 52.0%-60.0%) and 97.5% (95%CI 97.1%-97.8%) for hospital administrative coding.

CONCLUSIONS

An automated search strategy based on a combination of explicit and implicit concept retrieval is feasible to screen electronic health records for septic shock and outperforms an administrative coding based explicit approach.

The association of cardiovascular failure with treatment for ventilator-associated lower respiratory tract infection

PURPOSE

Ventilator associated-lower respiratory tract infections (VA-LRTIs), either ventilator-associated pneumonia (VAP) or tracheobronchitis (VAT), accounts for most nosocomial infections in intensive care units (ICU) including. Our aim was to determine if appropriate antibiotic treatment in patients with VA-LRTI will effectively reduce mortality in patients who had cardiovascular failure.

METHODS

This was a pre-planned subanalysis of a large prospective cohort of mechanically ventilated patients for at least 48 h in eight countries in two continents. Patients with a modified Sequential Organ Failure Assessment (mSOFA) cardiovascular score of 4 (at the time of VA-LRTI diagnosis and needed be present for at least 12 h) were defined as having cardiovascular failure.

RESULTS

VA-LRTI occurred in 689 (23.2%) out of 2960 patients and 174 (25.3%) developed cardiovascular failure. Patients with cardiovascular failure had significantly higher ICU mortality than those without (58% vs. 26.8%; p < 0.001; OR 3.7; 95% CI 2.6-5.4). A propensity score analysis found that the presence of inappropriate antibiotic treatment was an independent risk factor for ICU mortality in patients without cardiovascular failure, but not in those with cardiovascular failure. When the propensity score analysis was conducted in patients with VA-LRTI, the use of appropriate antibiotic treatment conferred a survival benefit for patients without cardiovascular failure who had only VAP.

CONCLUSIONS

Patients with VA-LRTI and cardiovascular failure did not show an association to a higher ICU survival with appropriate antibiotic treatment. Additionally, we found that in patients without cardiovascular failure, appropriate antibiotic treatment conferred a survival benefit for patients only with VAP.

TRIAL REGISTRY

ClinicalTrials.gov, number NCT01791530.