Antibiotic Utilization Patterns in Patients with Ventilator-Associated Pneumonia: A Canadian Context

STOP Signs: A Population-based Interrupted Time Series Analysis of Antibiotic Duration for Complicated Intraabdominal Infection Before and After the Publication of a Landmark RCT

OBJECTIVE

To determine if the STOP-IT randomized controlled trial changed antibiotic prescribing in patients with Complicated Intraabdominal Infection (CIAI).

SUMMARY OF BACKGROUND DATA

CIAI is common and causes significant morbidity. In May 2015, the STOP-IT randomized controlled trial showed equivalent outcomes between four-day and clinically determined antibiotic duration.

METHODS

This was a population-based retrospective cohort study using interrupted time series methods. The STOP-IT publication date was the exposure. Median duration of inpatient antibiotic prescription was the outcome. All adult patients admitted to four hospitals in Calgary, Canada between July 2012 and December 2018 with CIAI who survived at least four days following source control were included. Analysis was stratified by infectious source as appendix or biliary tract (group A) versus other (group B).

RESULTS

Among 4384 included patients, clinical and demographic attributes were similar before vs after publication. In Group A, median inpatient antibiotic duration was 3 days and unchanged from the beginning to the end of the study period [adjusted median difference -0.00 days, 95% confidence interval (CI) -0.37 - 0.37 days]. In Group B, antibiotic duration was shorter at the end of the study period (7.87 vs 6.73 days; -1.14 days, CI-2.37 - 0.09 days), however there was no change in trend following publication (-0.03 days, CI -0.16 - 0.09).

CONCLUSIONS

For appendiceal or biliary sources of CIAI, antibiotic duration was commensurate with the experimental arm of STOP-IT. For other sources, antibiotic duration was long and did not change in response to trial publication. Additional implementation science is needed to improve antibiotic stewardship.

Short-course antibiotic therapy: The next frontier in antimicrobial stewardship

Ensuring appropriate use of antibiotics is critical to preserving their effectiveness through limiting the development and spread of antimicrobial resistance. Evidence is accumulating that shorter courses of antibiotics are as effective as traditional longer regimens for many common infections and can reduce the risk of adverse events. Despite the availability of evidence and guidelines supporting short-course antibiotic therapy for these conditions, prolonged use of antibiotics remains common. This article will review the origins and evolution of our approach regarding antimicrobial prescription duration, the evidence for the use of short-course therapy for selected infections, barriers to the uptake of this practice and potential approaches that can be taken to reduce inappropriately long antibiotic use.

Inappropriate use of clinical practices in Canada: a systematic review

Background:

Inappropriate health care leads to negative patient experiences, poor health outcomes and inefficient use of resources. We aimed to conduct a systematic review of inappropriately used clinical practices in Canada.

Methods:

We searched multiple bibliometric databases and grey literature to identify inappropriately used clinical practices in Canada between 2007 and 2021. Two team members independently screened citations, extracted data and assessed methodological quality. Findings were synthesized in 2 categories: diagnostics and therapeutics. We reported ranges of proportions of inappropriate use for all practices. Medians and interquartile ranges (IQRs), based on the percentage of patients not receiving recommended practices (underuse) or receiving practices not recommended (overuse), were calculated. All statistics are at the study summary level.

Results:

We included 174 studies, representing 228 clinical practices and 28 900 762 patients. The median proportion of inappropriate care, as assessed in the studies, was 30.0% (IQR 12.0%–56.6%). Underuse (median 43.9%, IQR 23.8%–66.3%) was more frequent than overuse (median 13.6%, IQR 3.2%–30.7%). The most frequently investigated diagnostics were glycated hemoglobin (underused, range 18.0%–85.7%, n = 9) and thyroid-stimulating hormone (overused, range 3.0%–35.1%, n = 5). The most frequently investigated therapeutics were statin medications (underused, range 18.5%–71.0%, n = 6) and potentially inappropriate medications (overused, range 13.5%–97.3%, n = 9).

Interpretation:

We have provided a summary of inappropriately used clinical practices in Canadian health care systems. Our findings can be used to support health care professionals and quality agencies to improve patient care and safety in Canada.

The Effects of Open and Closed Suction Methods on Occurrence of Ventilator Associated Pneumonia; a Comparative Study

INTRODUCTION

Endotracheal suctioning is a method commonly used to clean airway secretions in patients under mechanical ventilation (MV). This study aimed to compare the effects of open and closed suction methods on the occurrence of ventilator associated pneumonia (VAP).

METHODS

This comparative study was carried out on adult intensive care unit (ICU) patients in need of MV for more than 48 hours, from October 2018 to January 2019. Patients were randomly allocated to either closed tracheal suction system (CTSS) group or open tracheal suction system (OTSS) group. Patients were monitored for developing VAP within 72 hours of intubation and the findings were compared between groups.

RESULTS

120 cases with the mean age of 57.91±19.9 years were randomly divided into two groups (56.7% male). The two groups were similar regarding age (p = 0.492) and sex (p = 0.713) distribution. 22 (18.3%) cases developed VAP (12 (20%) in OSST group and 10 (16.7%) in CSST; p = 0.637). The most prevalent bacterial causes of VAP were Acinetobacter_Baumannii (72.7%), Klebsiella pneumoniae (18.2%), and Methicillin-Resistant Staphylococcus aureus (9.1%), respectively. There was not any significant difference between groups regarding the mean duration of remaining under MV (p = 0.623), mean duration of hospitalization (p = 0.219), frequency of VAP (p = 0.637), and mortality (p = 0.99).

CONCLUSION

It seems that type of endotracheal suction system (OSST vs. CSST) had no effect on occurrence of VAP and other outcomes such as duration of need for MV and ICU stay as well as mortality.

Prevalence, predictors, and consequences of inappropriate empiric antimicrobial therapy for complicated urinary tract and intra-abdominal infections in Winnipeg hospitals

Information on inappropriate empiric antimicrobial therapy (ET) in Canadian hospitals is scarce. All Manitobans 18 years of age and over who were admitted to a hospital in Winnipeg with a complicated urinary tract infection (cUTI) or complicated intra-abdominal infection (cIAI) from January 2006 to December 2014 were eligible for inclusion in this cohort study. The prevalence of inappropriate ET was 11% for cUTI patients and 9% for cIAI patients. The risk of receiving inappropriate ET was higher for older patients (cUTI patients 65 or older had 2-fold increased risk compared to younger patients; odds ratio 2.1, 95% confidence interval 1.3-3.6; this was 1.6 [0.7-3.5] for cIAI patients) and those hospitalized in the previous year: 1.5 (1.0-2.4) in cUTIs and 1.5 (0.6-3.4) in cIAIs. The risk for a hospital stay over 3 weeks was increased for inappropriate ET in cUTI patients, 2.3 (1.4-3.7), but not in cIAI patients, 0.9 (0.4-2.1).

Bacteriologic profile and susceptibility pattern of mechanically ventilated paediatric patients with pneumonia

AIM

Due to the current widespread bacterial resistance to many antibiotics - especially extended-spectrum β-lactams, carbapenems, and anti-pseudomonal drugs - therapy for severe pneumonia is very challenging. This study aimed to assess antimicrobial sensitivity patterns and optimisation of the antibiotic stewardship program applied at a university-affiliated paediatric intensive care unit (PICU).

SUBJECTS AND METHODS

This prospective cohort study included all patients aged 1 month to 12 years, admitted to the PICU with severe pneumonia episodes indicated for mechanical ventilation, and were followed up and investigated. Non-bronchoscopic bronchoalveolar lavage specimens were tested for positive microbiological yields and examined for their susceptibility pattern.

RESULTS

Of 85 patients with 96 episodes, 69 of them yielded positive growth: 43 were community-acquired pneumonia episodes, 62.79% of which were of unidentified cause. The isolated bacteria were predominantly due to Chlamydia pneumonia (18.6%) followed by Staphylococcus aureus and its resistant form (9.3%). Hospital and ventilator-associated pneumonia were mainly related to Gram-negative bacteria (91.67% and 87.8%, respectively), especially Klebsiella acinetobacter and Pseudomonas. There was a significant increase in multi-drug resistance among Gram-negative bacteria, which was considered an independent risk factor of mortality (P=0.003).

CONCLUSION

Severe community-acquired pneumonia was treated with macrolides in combination with vancomycin or linezolid if methicillin-resistant S. aureus was suspected. This was appropriate, in view of its causative agents and their susceptibility pattern. Hospital and ventilator-associated pneumonia caused by resistant Gram-negative organisms might have better outcomes by adding tigecycline or colistin in combination with fluoroquinolones. Owing to the widespread resistance of many Gram-negative bacteria, it is recommended that the antibiotic stewardship program be frequently updated.

Ventilator-Associated Pneumonia and Events in Pediatric Intensive Care: A Single Center Study

OBJECTIVES

Ventilator-associated pneumonia is the second most common nosocomial infection in pediatric intensive care. The Centers for Disease Control and Prevention recently issued diagnosis criteria for pediatric ventilator-associated pneumonia and for ventilator-associated events in adults. The objectives of this pediatric study were to determine the prevalence of ventilator-associated pneumonia using these new Centers for Disease Control and Prevention criteria, to describe the risk factors and management of ventilator-associated pneumonia, and to assess a simpler method to detect ventilator-associated pneumonia with ventilator-associated event in critically ill children.

DESIGN

Retrospective, observational, single-center.

SETTING

PICU in a tertiary-care university hospital.

PATIENTS

Consecutive critically ill children mechanically ventilated for greater than or equal to 48 hours between November 2013 and November 2015.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 304 patients mechanically ventilated for greater than or equal to 48 hours, 284 were included. Among them, 30 (10.6%) met clinical and radiologic Centers for Disease Control and Prevention criteria for ventilator-associated pneumonia, yielding an prevalence of 7/1,000 mechanical ventilation days. Median time from mechanical ventilation onset to ventilator-associated pneumonia diagnosis was 4 days. Semiquantitative culture of tracheal aspirates was the most common microbiological technique. Gram-negative bacteria were found in 60% of patients, with a predominance of Haemophilus influenzae and Pseudomonas aeruginosa. Antibiotic therapy complied with adult guidelines. Compared with patients without ventilator-associated pneumonia, those with ventilator-associated pneumonia had significantly longer median durations of mechanical ventilation (15 vs 6 d; p < 0.001) and PICU stay (19 vs 9 d; p < 0.001). By univariate analysis, risk factors for ventilator-associated pneumonia were younger age, reintubation, acute respiratory distress syndrome, and continuous enteral feeding. Among the 30 patients with ventilator-associated pneumonia, 17 met adult ventilator-associated event's criteria (sensitivity, 56%).

CONCLUSIONS

Ventilator-associated pneumonia is associated with longer times on mechanical ventilation and in the PICU. Using the ventilator-associated event criteria is of interest to rapidly screen for ventilator-associated pneumonia in children. However, sensitivity must be improved by adapting these criteria to children.

Antimicrobial Stewardship Opportunities in Critically Ill Patients with Gram-Negative Lower Respiratory Tract Infections: A Multicenter Cross-Sectional Analysis

INTRODUCTION

Lower respiratory tract infections (LRTIs) are a major cause of morbidity and death. Because of changes in how LRTIs are defined coupled with the increasing prevalence of drug resistance, there is a gap in knowledge regarding the current burden of antimicrobial use for Centers for Disease Control and Prevention (CDC)-defined LRTIs. We describe the infection characteristics, antibiotic consumption, and clinical and economic outcomes of patients with Gram-negative (GN) LRTIs treated in intensive care units (ICUs).

METHODS

This was a retrospective, observational, cross-sectional study of adult patients treated in ICUs at two large academic medical centers in metropolitan Detroit, Michigan, from October 2013 to October 2015. To meet the inclusion criteria, patients must have had CDC-defined LRTI caused by a GN pathogen during ICU stay. Microbiological assessment of available Pseudomonas aeruginosa isolates included minimum inhibitory concentrations for key antimicrobial agents.

RESULTS

Four hundred and seventy-two patients, primarily from the community (346, 73.3%), were treated in medical ICUs (272, 57.6%). Clinically defined pneumonia was common (264, 55.9%). Six hundred and nineteen GN organisms were identified from index respiratory cultures: P. aeruginosa was common (224, 36.2%), with 21.6% of these isolates being multidrug resistant. Cefepime (213, 45.1%) and piperacillin/tazobactam (174, 36.8%) were the most frequent empiric GN therapies. Empiric GN therapy was inappropriate in 44.6% of cases. Lack of in vitro susceptibility (80.1%) was the most common reason for inappropriateness. Patients with inappropriate empiric GN therapy had longer overall stay, which translated to a median total cost of care of $79,800 (interquartile range $48,775 to $129,600) versus $68,000 (interquartile range $38,400 to $116,175), p = 0.013. Clinical failure (31.5% vs 30.0%, p = 0.912) and in-hospital all-cause mortality (26.4% vs 25.9%, p = 0.814) were not different.

CONCLUSION

Drug-resistant pathogens were frequently found and empiric GN therapy was inappropriate in nearly 50% of cases. Inappropriate therapy led to increased lengths of stay and was associated with higher costs of care.

Antibiotic consumption and ventilator-associated pneumonia rates, some parallelism but some discrepancies

Ventilator-associated pneumonia (VAP) is a common infection in intensive care units (ICUs) but its clinical definition is neither sensitive nor specific and lacks accuracy and objectivity. New defining criteria were proposed in 2013 by the National Healthcare Safety Network (NHSN) in order to more accurately conduct surveillance and track prevention progress. Although there is a consistent trend towards a decrease in VAP incidence during the last decade, significant differences in VAP rates have been reported and are persistently lower in NHSN and other American reports (0.0 to 4.4 VAP per 1,000 ventilator-days in 2012) compared to the European Centre for Disease Prevention and Control (ECDC) data (10 VAP per 1,000 ventilator-days in 2014). In the United States, VAP has been proposed as an indicator of quality of care in public reporting, and the threat of financial penalties for this diagnosis has put pressure on hospitals to minimize VAP rates that may lead to artificial lower values, independently of patient care. Although prevention bundles may contribute for encouraging reductions in VAP incidence, both pathophysiologic and epidemiologic factors preclude a zero-VAP rate. It would be expected from the trend of reduction of VAP incidence that the consumption of antibiotics would also decrease in particular in those hospitals with lowest VAP rates. However, ICU reports show a steadily use of antibiotics for nosocomial pneumonia in 15% of patients and both ECDC and NHSN data on antibiotic consumption showed no significant trend. Knowledge of bacterial epidemiology and resistance profiles for each ICU has great relevance in order to understand trends of antibiotic use. The new NHSN criteria provide a more objective and quantitative data based VAP definition, including an antibiotic administration criterion, allowing, in theory, a more comprehensive assessment and a reportable benchmark of the observed VAP and antibiotic consumption variability.