Beta-Lactam Infusion in Severe Sepsis (BLISS): a prospective, two-centre, open-labelled randomised controlled trial of continuous versus intermittent beta-lactam infusion in critically ill patients with severe sepsis

Continuous versus intermittent bolus dosing of beta-lactam antibiotics in a South African multi-disciplinary intensive care unit: A randomized controlled trial

BACKGROUND

Beta-lactams exhibit time-dependent bactericidal effects with continuous infusion (CI) suggested to provide superior antibiotic concentrations compared to intermittent bolus (IB).

OBJECTIVE

To determine whether beta-lactam CI improves day 14 clinical cure compared to IB in a South African, multi-disciplinary intensive care unit (ICU).

METHODS

Adult patients with sepsis receiving amoxicillin-clavulanate, piperacillin-tazobactam, imipenem-cilastatin and meropenem were randomized to 24-hour CI or IB. On screening, patients who received study antibiotics for more than 24 h, pregnant patients or patients on renal replacement therapy were excluded. The primary outcome, clinical cure, was defined as completion of antibiotics by day 14 without recommencement within 48 h. Secondary outcomes included ICU length of stay (LOS), ICU, day 28 and day 90 mortality.

RESULTS

We enrolled 122 patients. The groups were balanced for baseline age, weight, sex, severity of illness, organ support, HIV status, diagnostic category and site of infection. Median antibiotic duration, CI group, 7 days (IQR 5-8.5) vs. IB group, 6 days (IQR 4-8), p=0.191, and median ICU LOS, CI, 9.5 days (IQR 6-15.5) vs. IB, 9 days (IQR 5-16), p= 0.575, were similar. Clinical cure in the CI group was 81% (52/64) vs. 74.1% (43/58) in the IB group), p=0.345. Day 90 relative risk of death was 0,57, 95% Confidence Interval 0.32 - 1.01) for the CI group compared to IB.

CONCLUSION

Among critically ill patients meeting the sepsis-3 definition, this study could not demonstrate the superiority of continuous infusion of beta-lactam antibiotics compared to intermittent bolus in achieving a clinical cure.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2024

The 2024 revised edition of the Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock (J-SSCG 2024) is published by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine. This is the fourth revision since the first edition was published in 2012. The purpose of the guidelines is to assist healthcare providers in making appropriate decisions in the treatment of sepsis and septic shock, leading to improved patient outcomes. We aimed to create guidelines that are easy to understand and use for physicians who recognize sepsis and provide initial management, specialized physicians who take over the treatment, and multidisciplinary healthcare providers, including nurses, physical therapists, clinical engineers, and pharmacists. The J-SSCG 2024 covers the following nine areas: diagnosis of sepsis and source control, antimicrobial therapy, initial resuscitation, blood purification, disseminated intravascular coagulation, adjunctive therapy, post-intensive care syndrome, patient and family care, and pediatrics. In these areas, we extracted 78 important clinical issues. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 42 GRADE-based recommendations, 7 good practice statements, and 22 information-to-background questions were created as responses to clinical questions. We also described 12 future research questions.

Impact of prolonged versus intermittent infusion of meropenem on mortality and clinical outcomes in patients with severe infection: A systematic review and meta-analysis

OBJECTIVES

To compare the clinical outcomes of patients with severe infection treated with prolonged or intermittent infusion of meropenem.

METHODS

PubMed, Embase, and Cochrane Central databases were searched until July 2023. Randomized controlled trials (RCTs) or observational studies comparing prolonged versus intermittent infusion of meropenem were considered eligible. The primary outcomes included all-cause mortality and clinical improvement, while secondary outcomes encompassed hospital and intensive care unit (ICU) stay duration, microbial eradication rate, and adverse events. A meta-analysis was conducted using a random-effects model. The risk of bias of included studies was assessed using the modified JADAD scale for RCTs and the Newcastle-Ottawa Scale for observational studies.

RESULTS

Fourteen studies were included, with a total of 1698 patients. Prolonged infusion of meropenem was associated with a significantly lower mortality rate compared to intermittent infusion (RR = 0.81, 95 % CI: 0.68-0.98). It also significantly improved clinical improvement rates (RR = 1.35, 95 % CI: 1.11-1.64) and microbial eradication rates (RR = 1.19, 95 % CI: 1.08-1.32). There were no statistically significant differences in ICU length of stay or hospital length of stay. Subgroup analyses showed that prolonged infusion was significantly associated with lower mortality and better clinical improvement rates in patients with an APACHE II score <20.

CONCLUSIONS

Prolonged infusion of meropenem is more effective than intermittent infusion in reducing mortality, improving clinical outcomes, and enhancing microbial eradication, without increasing adverse events. These benefits are particularly evident in patients with lower disease severity (APACHE II < 20), emphasizing the importance of patient stratification in optimizing treatment strategies.

REGISTRATION

This systematic review and meta-analysis is registered with PROSPERO (number: CRD42023445360).

Piperacillin/Tazobactam Susceptibility Test Interpretive Criteria for Enterobacterales: Recommendations From the United States Committee on Antimicrobial Susceptibility Testing

The in vitro susceptibility testing interpretive criteria (STIC) for piperacillin/tazobactam (TZP) against Enterobacterales were recently updated by the US Food and Drug Administration, Clinical and Laboratory Standards Institute, and European Committee on Antimicrobial Susceptibility Testing. The United States Committee on Antimicrobial Susceptibility Testing (USCAST) also recently reviewed TZP STIC for Enterobacterales and arrived at different STIC for Enterobacterales. Here, we explain our recommendations and rationale behind them. Based on our review of the available data, USCAST does not recommend TZP STIC for certain Enterobacterales species that have a moderate to high likelihood of clinically significant AmpC production (Enterobacter cloacae, Citrobacter freundii, and Klebsiella aerogenes only) or for third-generation cephalosporin-nonsusceptible Enterobacterales. USCAST recommends a TZP susceptibility breakpoint of ≤ 16/4 mg/L for third-generation cephalosporin-susceptible Enterobacterales and only endorses the use of extended infusion TZP regimens for patients with infections due to these pathogens.

Improving pharmacokinetic/pharmacodynamic outcomes of antimicrobial therapy for pneumonia in the ICU

INTRODUCTION

Pneumonia remains a significant global health challenge due to its high prevalence and mortality rate, and challenging treatment. This review explores the best strategies to optimize the antibiotic therapy for pneumonia in critically ill patients, focusing on pharmacokinetics, pharmacodynamics, and therapeutic data.

AREAS COVERED

A review of scientific publications on severe pneumonia highlights the challenges of optimizing antibiotic use to improve lung diffusion, bacterial killing, and achieving PK/PD targets, emphasizing the need to understand microbiological epidemiology and MIC breakpoints. Key strategies like nebulization, therapeutic drug monitoring, and emerging technologies such as ELF TDM and nanomaterial-based drug delivery systems are essential for optimizing PK/PD outcomes and addressing antimicrobial resistance.

EXPERT OPINION

Improving our understanding of pulmonary pharmacokinetics and optimizing their tissue diffusion are instrumental for achieving precision antibiotic therapy for severe pneumonia. By addressing current limitations and embracing interdisciplinary collaboration, we can pave the way for more efficient personalized approaches in infectious disease management.

Detailed regimens for the prolonged β-lactam infusion therapy

A recent systematic review and meta-analysis of randomized controlled trials (RCTs) evaluated the efficacy and safety of prolonged versus intermittent β-lactam infusion in adult sepsis patients. The findings revealed a significant decrease in all-cause mortality and marked clinical success in the prolonged infusion group. Unfortunately, however, the manuscript lacked data and discussion for the specific regimens of prolonged β-lactam infusion defined in the included 15 RCT studies, which are herein additionally provided. Excluding one RCT, all protocols adopted a continuous infusion for the prolonged treatment. Except for three RCTs, dosages and timings of bolus injection were clearly defined. The total daily antibiotic dose for the continuous therapy was equivalent to those recommended for intermittent therapy. We believe this supplementary data aids clinicians in providing prolonged β-lactam infusions, contributing to enhanced treatment outcomes for patients suffering from severe sepsis or septic shock.

Meta-analysis on safety of standard vs. prolonged infusion of beta-lactams

BACKGROUND

Efficacy for prolonged infusion beta-lactam dosing schemes has been previously described, but there has been less focus on the safety of standard vs. prolonged infusion protocols of beta-lactams. This study explored differences in adverse drug reactions (ADRs) reported for beta-lactams between each of these infusion protocols.

METHODS

A systematic review of MEDLINE literature databases via PubMed was conducted and references were reviewed. Articles were compiled and assessed with specific inclusion/exclusion criteria. We included randomised and nonrandomised, prospective, and retrospective cohort studies that reported adverse drug reactions (ADRs) due to either standard (30-60 mins) or prolonged (≥3 h) infusions of beta-lactam infusions. Total ADRs between strategies were analysed by infusion methodology. The most consistently reported ADRs were subject to meta-analysis across studies.

RESULTS

12 studies met inclusion/exclusion criteria with data for 4163 patients. There was insufficient data to systematically analyse neurotoxicity or cytopenias. Seven studies reported on nephrotoxicity outcomes with no significant difference in event rates between standard (n = 434/2258,19.2%) vs. prolonged infusion (n = 266/1271, 20.9%) of beta-lactams (OR = 1.08, 95% CI [0.91, 1.29]). Six studies observed diarrhoea in a total of 759 patients with no significant difference in patients of standard (n = 18/399, 4.5%) vs. prolonged (n = 19/360, 5.3%) infusion of beta-lactams (OR = 1.14, 95% CI [0.59,2.20]).

CONCLUSION

Prolonged and standard infusion schemes for beta-lactams demonstrated similar adverse event rates. Future research should focus on improved standardisation of adverse effect definitions and a priori aim to study neurotoxicity and cytopenias. Consistent recording of ADRs and standardised definitions of these reactions will be paramount to further study of this subject.

Utilization of cefepime therapeutic drug monitoring in febrile neutropenia patients with hematologic malignancies

INTRODUCTION

Cefepime is a fourth-generation cephalosporin and is a workhorse for the empiric treatment of febrile neutropenia (FN). Beta-lactam therapeutic drug monitoring (TDM) has emerged as a dose optimization strategy in patient populations with altered kinetics. Prior literature has demonstrated that patients with FN exhibit augmented renal clearance which may lead to subtherapeutic drug concentrations with standard dosing regimens. The aim of this study was to evaluate pharmacokinetic/pharmacodynamic (PK/PD) target attainment and clinical outcomes in patients with hematologic malignancies and FN who were treated empirically with cefepime.

METHODS

This was a prospective, single-center study of adults with hematologic malignancies and FN admitted to the inpatient unit. The primary outcome was PK/PD target attainment (defined as 100% free time greater than minimum inhibitory concentration (100% fT > MIC)). Secondary clinical outcomes were time to defervescence, time to ANC recovery, in-hospital mortality, and cefepime failure.

RESULTS

There were 55 patients in our study. Forty-three (78%) patients achieved the primary outcome of PK/PD target attainment. The mean time to defervescence was similar between those that achieved PK/PD target attainment and those that did not (95% CI -0.75 to 1.25, p = 0.62).

CONCLUSIONS

This study showed that standard cefepime dosing in patients with hematologic malignancies and FN does not result in achievement of 100% fT > MIC in all patients. Patients in the group that did not achieve PK/PD target attainment were younger with increased creatinine clearance, indicating that cefepime TDM may be especially beneficial in these patients.

Meropenem pharmacokinetics in cerebrospinal fluid: comparing intermittent and continuous infusion strategies in critically ill patients-a prospective cohort study

Meropenem penetration into the cerebrospinal fluid (CSF) is subject to high interindividual variability resulting in uncertain target attainment in CSF. Recently, several authors recommended administering meropenem as a continuous infusion (CI) to optimize CSF exposure. This study aimed to compare the concentrations and pharmacokinetics of meropenem in CSF after intermittent infusion (II) and CI. This prospective, observational study (NCT04426383) included critically ill patients with external ventricular drains who received either II or CI of meropenem. Meropenem pharmacokinetics in plasma and CSF were characterized using population pharmacokinetic modeling (NONMEM 7.5). The developed model was used to compare the concentration-time profile and probability of target attainment (PTA) between II and CI. A total of 16 patients (8 CI, 8 II; samples: nplasma = 243, nCSF = 263) were recruited, with nine patients (5 CI, 4 II) suffering from cerebral and seven patients from extracerebral infections. A one-compartment model described the plasma concentrations adequately. Meropenem penetration into the CSF (partition coefficient (KP), cCSF/cplasma) was generally low (6.0%), exhibiting substantial between-subject variability (coefficient of variation: 84.0%). There was no correlation between the infusion mode and KP, but interleukin (IL)-6 measured in CSF showed a strong positive correlation with KP (P < 0.001). Dosing simulations revealed no relevant differences in CSF concentrations and PTA in CSF between CI and II. Our study did not demonstrate increased penetration rates or higher concentrations of meropenem in the CSF with CI compared with II.

CLINICAL TRIALS

This study is registered with ClinicalTrials.gov as NCT04426383.

A Retrospective Analysis of Intravenous Push versus Extended Infusion Meropenem in Critically Ill Patients

Meropenem is a broad-spectrum antibiotic used for the treatment of multi-drug-resistant infections. Due to its pharmacokinetic profile, meropenem's activity is optimized by maintaining a specific time the serum concentration remains above the minimum inhibitory concentration (MIC) via extended infusion (EI), continuous infusion, or intermittent infusion dosing strategies. The available literature varies regarding the superiority of these dosing strategies. This study's primary objective was to determine the difference in time to clinical stabilization between intravenous push (IVP) and EI administration. We performed a retrospective pilot cohort study of 100 critically ill patients who received meropenem by IVP (n = 50) or EI (n = 50) during their intensive care unit (ICU) admission. There was no statistically significant difference in the overall achievement of clinical stabilization between IVP and EI (48% vs. 44%, p = 0.17). However, the median time to clinical stability was shorter for the EI group (20.4 vs. 66.2 h, p = 0.01). EI administration was associated with shorter hospital (13 vs. 17 days; p = 0.05) and ICU (6 vs. 9 days; p = 0.02) lengths of stay. Although we did not find a statistically significant difference in the overall time to clinical stabilization, the results of this pilot study suggest that EI administration may produce quicker clinical resolutions than IVP.

Prolonged vs Intermittent Infusions of β-Lactam Antibiotics in Adults With Sepsis or Septic Shock: A Systematic Review and Meta-Analysis

Importance

There is uncertainty about whether prolonged infusions of β-lactam antibiotics improve clinically important outcomes in critically ill adults with sepsis or septic shock.

Objective

To determine whether prolonged β-lactam antibiotic infusions are associated with a reduced risk of death in critically ill adults with sepsis or septic shock compared with intermittent infusions.

Data Sources

The primary search was conducted with MEDLINE (via PubMed), CINAHL, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov from inception to May 2, 2024.

Study Selection

Randomized clinical trials comparing prolonged (continuous or extended) and intermittent infusions of β-lactam antibiotics in critically ill adults with sepsis or septic shock.

Data Extraction and Synthesis

Data extraction and risk of bias were assessed independently by 2 reviewers. Certainty of evidence was evaluated with the Grading of Recommendations Assessment, Development and Evaluation approach. A bayesian framework was used as the primary analysis approach and a frequentist framework as the secondary approach.

Main Outcomes and Measures

The primary outcome was all-cause 90-day mortality. Secondary outcomes included intensive care unit (ICU) mortality and clinical cure.

Results

From 18 eligible randomized clinical trials that included 9108 critically ill adults with sepsis or septic shock (median age, 54 years; IQR, 48-57; 5961 men [65%]), 17 trials (9014 participants) contributed data to the primary outcome. The pooled estimated risk ratio for all-cause 90-day mortality for prolonged infusions of β-lactam antibiotics compared with intermittent infusions was 0.86 (95% credible interval, 0.72-0.98; I2 = 21.5%; high certainty), with a 99.1% posterior probability that prolonged infusions were associated with lower 90-day mortality. Prolonged infusion of β-lactam antibiotics was associated with a reduced risk of intensive care unit mortality (risk ratio, 0.84; 95% credible interval, 0.70-0.97; high certainty) and an increase in clinical cure (risk ratio, 1.16; 95% credible interval, 1.07-1.31; moderate certainty).

Conclusions and Relevance

Among adults in the intensive care unit who had sepsis or septic shock, the use of prolonged β-lactam antibiotic infusions was associated with a reduced risk of 90-day mortality compared with intermittent infusions. The current evidence presents a high degree of certainty for clinicians to consider prolonged infusions as a standard of care in the management of sepsis and septic shock.

Trial Registration

PROSPERO Identifier: CRD42023399434.

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Extended-Infusion β-Lactam Therapy, Mortality, and Subsequent Antibiotic Resistance Among Hospitalized Adults With Gram-Negative Bloodstream Infections

Importance

Current evidence is conflicting for associations of extended-infusion β-lactam (EI-BL) therapy with clinical outcomes.

Objective

To investigate the association of EI-BL therapy with survival, adverse events, and emergence of antibiotic resistance in adults with gram-negative bloodstream infections (GN-BSI).

Design, Setting, and Participants

This cohort study of consecutive adults with GN-BSI admitted to 24 United States hospitals between January 1, 2019, and December 31, 2019, receiving EI-BL were compared with adults with GN-BSI receiving the same agents as intermittent infusion β-lactam (II-BL; ≤1-hour infusions). Statistical analysis was performed from January to October 2023.

Exposures

EI-BL (ie, ≥3-hour infusion).

Main Outcomes and Measures

EI-BL and II-BL groups underwent 1:3 nearest-neighbor propensity score matching (PSM) without replacement. Multivariable regression was applied to the PSM cohort to investigate outcomes, all censored at day 90. The primary outcome was mortality; secondary outcomes included antibiotic adverse events and emergence of resistance (≥4-fold increase in the minimum inhibitory concentration of the β-lactam used to treat the index GN-BSI).

Results

Among the 4861 patients included, 2547 (52.4%) were male; and the median (IQR) age was 67 (55-77) years. There were 352 patients in the EI-BL 1:3 PSM group, and 1056 patients in the II-BL 1:3 PSM group. Among 1408 PSM patients, 373 (26.5%) died by day 90. The odds of mortality were lower in the EI-BL group (adjusted odds ratio [aOR], 0.71 [95% CI, 0.52-0.97]). In a stratified analysis, a survival benefit was only identified in patients with severe illness or elevated minimum inhibitory concentrations (ie, in the intermediate range for the antibiotic administered). There were increased odds of catheter complications (aOR, 3.14 [95% CI, 1.66-5.96]) and antibiotic discontinuation because of adverse events (eg, acute kidney injury, cytopenias, seizures) in the EI-BL group (aOR, 3.66 [95% CI, 1.68-7.95]). Emergence of resistance was similar in the EI-BL and II-BL groups at 2.9% vs 7.2%, respectively (P = .35).

Conclusions and Relevance

In this cohort study of patients with GN-BSI, EI-BL therapy was associated with reduced mortality for patients with severe illness or those infected with nonsusceptible organisms; potential advantages in other groups remain unclear and need to be balanced with potential adverse events. The subsequent emergence of resistance warrants investigation in a larger cohort.

Revealing the role of Peg13: A promising therapeutic target for mitigating inflammation in sepsis

To investigate the role of Peg13 in modulating the inflammatory response in sepsis, we established Lipopolysaccharide (LPS)-induced 293T cells and mouse models. Peg13 expression was assessed at various time points after infection using RT-qPCR. The levels of high mobility group box 1 (HMGB1) and interleukin-6 (IL-6) were quantified through ELISA. A total of 44 septic patients and 36 healthy participants were recruited to measure Peg13 and HMGB1 levels in the blood. Peg13 demonstrated significant down-regulation in the supernatant of LPS-induced 293T cells and in the blood of LPS-induced mice. Moreover, the levels of proinflammatory cytokines HMGB1 and IL-6 were elevated in both the supernatant of LPS-induced cell models and blood specimens from LPS-induced murine models, and this elevation could be notably reduced by Peg13 suppression. In a clinical context, Peg13 and HMGB1 levels were higher in septic patients compared to healthy subjects. Peg13 exhibited a negative correlation with HMGB1, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) among septic patients. Peg13 mitigates the inflammatory response by reducing the release of proinflammatory cytokines HMGB1 and IL-6 in sepsis, presenting a potential therapeutic target for alleviating inflammation in sepsis treatment.

Decreased risk of underdosing with continuous infusion versus intermittent administration of cefotaxime in patients with sickle cell disease and acute chest syndrome

OBJECTIVE

Underdosing of antibiotics is common in patients with sickle cell disease (SCD). We hypothesized that in critically-ill patients with SCD receiving cefotaxime during acute chest syndrome, the continuous infusion may outperform the intermittent administration in achieving pharmacokinetic/pharmacodynamic targets.

DESIGN

Prospective before-after study.

SETTINGS

Intensive-care unit of a French teaching hospital and sickle cell disease referral center.

PATIENTS

Sixty consecutive episodes of severe acute chest syndrome in 58 adult patients with sickle cell disease.

INTERVENTIONS

Patients were treated with intermittent administration during the first period (April 2016 -April 2018) and with continuous infusion during the second period (May 2018 -August 2019).

MEASUREMENTS AND MAIN RESULTS

We included 60 episodes of acute chest syndrome in 58 patients (29 [25-34] years, 37/58 (64%) males). Daily dose of cefotaxime was similar between groups (59 [48-88] vs. 61 [57-64] mg/kg/day, p = 0.84). Most patients (>75%) presented a glomerular hyperfiltration with no difference between groups (p = 0.25). More patients had a cefotaxime trough level ≥2 mg/L with continuous infusion than intermittent administration: 28 (93%) vs. 5 (16%), p<0.001. The median residual concentration was higher in the continuous infusion than intermittent administration group: 10.5 [7.4-13.3] vs. 0 [0-0] mg/L, p<0.001. No infection relapse was observed in the entire cohort. Hospital length of stay was similar between groups.

CONCLUSION

As compared to intermittent administration, continuous infusion of cefotaxime maximizes the pharmacokinetic/pharmacodynamic parameters in patients with SCD. The clinical outcome did not differ between the two administration methods; however, the study was underpowered to detect such a difference.

Mortality of continuous infusion versus intermittent bolus of meropenem: a systematic review and meta-analysis of randomized controlled trials

Background

Meropenem belongs to the carbapenem class, which is categorized as beta-lactam antibiotics. These antibiotics are administered in intermittent bolus doses at specific time intervals. However, the continuous infusion approach ensures sustained drug exposure, maintaining the drug concentration above the minimum inhibitory concentration (MIC) throughout the entire treatment period. This study aimed to find out the association between continuous infusions of meropenem and mortality rates.

Materials and methods

We conducted a search of the PubMed/Medline, EMBASE, Cochrane Central, and ClinicalTrials.gov databases up to 14 August 2023. The six randomized controlled trials (RCTs) were identified and included in our analysis. The random-effects model was implemented using Comprehensive Meta-Analysis software to examine the outcomes.

Results

Our study included a total of 1,529 adult patients from six randomized controlled trials. The primary outcome indicated that continuous infusion of meropenem did not lead to reduction in the mortality rate (odds ratio = 0.844, 95% CI: 0.671-1.061, P =0.147). Secondary outcomes revealed no significant differences in ICU length of stay (LOS), ICU mortality, clinical cure, or adverse events between continuous infusion and traditional intermittent bolus strategies of meropenem. Notably, we observed significant improvements in bacterial eradication (odds ratio 19 = 2.207, 95% CI: 1.467-3.320, P < 0.001) with continuous infusion of meropenem. Our study also suggested that performing continuous infusion may lead to better bacterial eradication effects in resistant pathogens (coefficient: 2.5175, P = 0.0138*).

Conclusion

Continuous infusion of meropenem did not result in the reduction of mortality rates but showed potential in improving bacterial eradication. Furthermore, this strategy may be particularly beneficial for achieving better bacterial eradication, especially in cases involving resistant pathogens.

Management of Ventilator-Associated Pneumonia: Guidelines

Two recent major guidelines on diagnosis and treatment of ventilator-associated pneumonia (VAP) recommend consideration of local antibiotic resistance patterns and individual patient risks for resistant pathogens when formulating an initial empiric antibiotic regimen. One recommends against invasive diagnostic techniques with quantitative cultures to determine the cause of VAP; the other recommends either invasive or noninvasive techniques. Both guidelines recommend short-course therapy be used for most patients with VAP. Although neither guideline recommends use of procalcitonin as an adjunct to clinical judgment when diagnosing VAP, they differ with respect to use of serial procalcitonin to shorten the length of antibiotic treatment.

Carrimycin ameliorates lipopolysaccharide and cecal ligation and puncture-induced sepsis in mice

Carrimycin (CA), sanctioned by China's National Medical Products Administration (NMPA) in 2019 for treating acute bronchitis and sinusitis, has recently been observed to exhibit multifaceted biological activities, encompassing anti-inflammatory, antiviral, and anti-tumor properties. Despite these applications, its efficacy in sepsis treatment remains unexplored. This study introduces a novel function of CA, demonstrating its capacity to mitigate sepsis induced by lipopolysaccharide (LPS) and cecal ligation and puncture (CLP) in mice models. Our research employed in vitro assays, real-time quantitative polymerase chain reaction (RT-qPCR), and RNA-seq analysis to establish that CA significantly reduces the levels of pro-inflammatory cytokines, namely tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6), in response to LPS stimulation. Additionally, Western blotting and immunofluorescence assays revealed that CA impedes Nuclear Factor Kappa B (NF-κB) activation in LPS-stimulated RAW264.7 cells. Complementing these findings, in vivo experiments demonstrated that CA effectively alleviates LPS- and CLP-triggered organ inflammation in C57BL/6 mice. Further insights were gained through 16S sequencing, highlighting CA's pivotal role in enhancing gut microbiota diversity and modulating metabolic pathways, particularly by augmenting the production of short-chain fatty acids in mice subjected to CLP. Notably, a comparative analysis revealed that CA's anti-inflammatory efficacy surpasses that of equivalent doses of aspirin (ASP) and TIENAM. Collectively, these findings suggest that CA exhibits significant therapeutic potential in sepsis treatment. This discovery provides a foundational theoretical basis for the clinical application of CA in sepsis management.

Prolonged versus intermittent β-lactam infusion in sepsis: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The two latest studies on prolonged versus intermittent use of β-lactam antibiotics in patients with sepsis did not reach consistent conclusions, further contributing to the controversy surrounding the effectiveness of the prolonged β-lactam antibiotics infusion strategy. We conducted a systemic review and meta-analysis to evaluate the efficacy and safety of prolonged and intermittent β-lactam infusion in adult patients with sepsis.

METHODS

We systematically searched PubMed, EMBASE, and Cochrane Library databases for original randomized controlled trials comparing prolonged and intermittent β-lactam infusion in sepsis patients. A random-effects model was used to evaluate mortality, clinical success, microbiological success, and adverse events. We also conducted subgroup analyses to explore the impact of various factors on the mortality rates. Relative risk (RR) and corresponding 95% confidence intervals (CIs) were used to calculate the overall effect sizes for dichotomous outcomes. This meta-analysis was registered in PROSPERO (CRD42023463905).

RESULTS

We assessed 15 studies involving 2130 patients. In our comprehensive assessment, we found a significant reduction in all-cause mortality (RR, 0.83; 95% CI 0.72-0.97; P = 0.02) and a notable improvement in clinical success (RR, 1.16; 95% CI 1.03-1.31; P = 0.02) in the prolonged infusion group compared to the intermittent infusion group, whereas microbiological success did not yield statistically significant results (RR, 1.10; 95% CI 0.98-1.23; P = 0.11). No significant differences in adverse events were observed between the two groups (RR, 0.91; 95% CI 0.64-1.29; P = 0.60). Additionally, remarkable conclusions were drawn from subgroup analyses including studies with sample sizes exceeding 20 individuals per group (RR, 0.84; 95%CI 0.72-0.98; P = 0.03), research conducted post-2010 (RR, 0.84; 95%CI 0.72-0.98; P = 0.03), cases involving infections predominantly caused by Gram-negative bacteria (RR, 0.81; 95%CI 0.68-0.96; P = 0.02), as well as the administration of a loading dose (RR, 0.84; 95% CI 0.72-0.97; P = 0.02) and the use of penicillin (RR, 0.61; 95% CI 0.38-0.98; P = 0.04).

CONCLUSIONS

Compared to intermittent infusion, prolonged infusion of β-lactam antibiotics significantly decreases all-cause mortality among patients with sepsis and enhances clinical success without increasing adverse events.

Extended Infusion of Beta-Lactams and Glycopeptides: A New Era in Pediatric Care? A Systematic Review and Meta-Analysis

Optimizing antibiotic therapy is imperative with rising bacterial resistance and high infection mortality. Extended infusion defined as a continuous infusion (COI) or prolonged infusion (PI) of beta-lactams and glycopeptides might improve efficacy and safety compared to their intermittent administration (IA). This study aimed to evaluate the efficacy and safety of extended infusion in pediatric patients. Adhering to Cochrane standards, we conducted a systematic review with meta-analysis investigating the efficacy and safety of COI (24 h/d) and PI (>1 h/dose) compared to IA (≤1 h/dose) of beta-lactams and glycopeptides in pediatrics. Primary outcomes included mortality, clinical success, and microbiological eradication. Five studies could be included for the outcome mortality, investigating meropenem, piperacillin/tazobactam, cefepime, or combinations of these. The pooled relative risk estimate was 0.48 (95% CI 0.26-0.89, p = 0.02). No significant differences between the administration modes were found for the outcomes of clinical success, microbiological eradication (beta-lactams; glycopeptides), and mortality (glycopeptides). No study reported additional safety issues, e.g., adverse drug reactions when using COI/PI vs. IA. Our findings suggest that the administration of beta-lactams by extended infusion leads to a reduction in mortality for pediatric patients.

A descriptive pharmacokinetic/pharmacodynamic analysis of ceftazidime-avibactam in a case series of critically ill patients with augmented renal clearance

To describe the pharmacokinetics/pharmacodynamics (PK/PD) of a 2 h infusion of ceftazidime-avibactam (CAZ-AVI) in critically ill patients with augmented renal clearance (ARC). A retrospective review of all critically ill patients with ARC who were treated with CAZ-AVI between August 2020 and May 2023 was conducted. Patients whose 12-h creatinine clearance prior to CAZ-AVI treatment and steady-state concentration (Css) of CAZ-AVI were both monitored were enrolled. The free fraction (fCss) of CAZ-AVI was calculated from Css. The joint PK/PD targets of CAZ-AVI were considered optimal when a Css/minimum inhibitory concentration (MIC) ratio for CAZ ≥4 (equivalent to 100% fT > 4 MIC) and a Css/CT ratio of AVI >1 (equivalent to 100% fT > CT 4.0 mg/L) were reached simultaneously, quasioptimal when only one of the two targets was reached, and suboptimal when neither target was reached. The relationship between PK/PD goal achievement, microbial eradication and the clinical efficacy of CAZ-AVI was evaluated. Four patients were included. Only one patient achieved optimal joint PK/PD targets, while the other three reached suboptimal targets. The patient with optimal PK/PD targets achieved microbiological eradication, while the other three patients did not, but all four patients achieved good clinical efficacy. Standard dosages may not enable most critically ill patients with ARC to reach the optimal joint PK/PD targets of CAZ-AVI. Optimal drug dose adjustment of CAZ-AVI in ARC patients requires dynamic drug concentration monitoring.

Interprofessional Therapeutic Drug Monitoring of Carbapenems Improves ICU Care and Guideline Adherence in Acute-on-Chronic Liver Failure

(1) Background: Acute-on-chronic liver failure (ACLF) is a severe, rapidly progressing disease in patients with liver cirrhosis. Meropenem is crucial for treating severe infections. Therapeutic drug monitoring (TDM) offers an effective means to control drug dosages, especially vital for bactericidal antibiotics like meropenem. We aimed to assess the outcomes of implementing TDM for meropenem using an innovative interprofessional approach in ACLF patients on a medical intensive care unit (ICU). (2) Methods: The retrospective study was conducted on a medical ICU. The outcomes of an interprofessional approach comprising physicians, hospital pharmacists, and staff nurses to TDM for meropenem in critically ill patients with ACLF were examined in 25 patients. Meropenem was administered continuously via an infusion pump after the application of an initial loading dose. TDM was performed weekly using high-performance liquid chromatography (HPLC). Meropenem serum levels, implementation of the recommendations of the interprofessional team, and meropenem consumption were analyzed. (3) Results: Initial TDM for meropenem showed a mean meropenem serum concentration of 20.9 ± 9.6 mg/L in the 25 analyzed patients. Of note, in the initial TDM, only 16.0% of the patients had meropenem serum concentrations within the respective target range, while 84.0% exceeded this range. Follow-up TDM showed serum concentrations of 15.2 ± 5.7 mg/L (9.0-24.6) in Week 2 and 11.9 ± 2.3 mg/L (10.2-13.5) in Week 3. In Week 2, 41.7% of the patients had meropenem serum concentrations that were within the respective target range, while 58.3% of the patients were above this range. In Week 3, 50% of the analyzed serum concentrations of meropenem were within the targeted range, and 50% were above the range. In total, 100% of the advice given by the interprofessional team regarding meropenem dosing or a change in antibiotic therapy was implemented. During the intervention period, the meropenem application density was 37.9 recommended daily doses (RDD)/100 patient days (PD), compared to 42.1 RDD/100 PD in the control period, representing a 10.0% decrease. (4) Conclusions: Our interprofessional approach to TDM significantly reduced meropenem dosing, with all the team's recommendations being implemented. This method not only improved patient safety but also considerably decreased the application density of meropenem.

Prolonged vs intermittent intravenous infusion of β-lactam antibiotics for patients with sepsis: a systematic review of randomized clinical trials with meta-analysis and trial sequential analysis

BACKGROUND

The prolonged β-lactam antibiotics infusion has been an attractive strategy in severe infections, because it provides a more stable free drug concentration and a longer duration of free drug concentration above the minimum inhibitory concentration (MIC). We conducted this systematic review of randomized clinical trials (RCTs) with meta-analysis and trial sequential analysis (TSA) to compare the effects of prolonged vs intermittent intravenous infusion of β-lactam antibiotics for patients with sepsis.

METHODS

This study was prospectively registered on PROSPERO database (CRD42023447692). We searched EMBASE, PubMed, and Cochrane Library to identify eligible studies (up to July 6, 2023). Any study meeting the inclusion and exclusion criteria would be included. The primary outcome was all-cause mortality within 30 days. Two authors independently screened studies and extracted data. When the I2 values < 50%, we used fixed-effect mode. Otherwise, the random effects model was used. TSA was also performed to search for the possibility of false-positive (type I error) or false-negative (type II error) results.

RESULTS

A total of 4355 studies were identified in our search, and nine studies with 1762 patients were finally included. The pooled results showed that, compared with intermittent intravenous infusion, prolonged intravenous infusion of beta-lactam antibiotics resulted in a significant reduction in all-cause mortality within 30 days in patients with sepsis (RR 0.82; 95%CI 0.70-0.96; P = 0.01; TSA-adjusted CI 0.62-1.07). However, the certainty of the evidence was rated as low, and the TSA results suggested that more studies were needed to further confirm our conclusion. In addition, it is associated with lower hospital mortality, ICU mortality, and higher clinical cure. No significant reduction in 90-day mortality or the emergence of resistance bacteria was detected between the two groups.

CONCLUSIONS

Prolonged intravenous infusion of beta-lactam antibiotics in patients with sepsis was associated with short-term survival benefits and higher clinical cure. However, the TSA results suggested that more studies are needed to reach a definitive conclusion. In terms of long-term survival benefits, we could not show an improvement.

In silico evaluation of a beta-lactam dosing guideline among adults with serious infections

STUDY OBJECTIVE

The aim of this study was to compare the achievement of therapeutic pharmacokinetic-pharmacodynamic (PK-PD) exposure targets for beta-lactam antibiotics using product information dosing or guideline-based dosing for the treatment of serious infections.

DESIGN

In silico study.

DATA SOURCE

ID-ODSTM (Individually Designed Optimum Dosing Strategies).

PATIENTS AND INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

In silico product information and guideline-based dosing simulations for cefepime, ceftazidime, flucloxacillin, meropenem, and piperacillin/tazobactam were performed using pharmacokinetic models from seriously ill patient populations. The median simulated concentration at 48 and 96 h was used to measure the probability of target attainment (PTA) to achieve predefined therapeutic and toxicity PK-PD targets. A multiple linear regression model was constructed to identify the effect of guideline-based dosing covariates on achieving pre-defined therapeutic targets. In total, 480 dosing simulations were performed. The PTA percentage with guideline-based dosing at 48 and 96 h was 80% and 68%, respectively, yielding significantly higher results when compared to product information dosing (48.45% and 49%, respectively), p < 0.001 at both time points. At 48 h, predefined toxicity thresholds were exceeded in 4.7% and 0% of simulations for guideline-based and product information-based dosing, respectively (p = 0.002). eGFR was significantly associated with the % PTA by guideline-based dosing, with eGFR values of 20 and 50 ml/min both statistically significant in leading to an increase in PTA.

CONCLUSIONS

Our study demonstrated that achievement of PK-PD exposures associated with an increased likelihood of effectiveness was more likely to occur with guideline-based dosing; especially at 48 h.

Relationship Between Real-time TDM-guided Pharmacodynamic Target Attainment of Continuous Infusion Beta-lactam Monotherapy and Microbiologic Outcome in the Treatment of Critically Ill Children With Severe Documented Gram-negative Infections

OBJECTIVES

To explore the relationship between real-time therapeutic drug monitoring (TDM)-guided pharmacodynamic target attainment of continuous infusion (CI) beta-lactam monotherapy and microbiological outcome in the treatment of critically ill children with severe documented Gram-negative infections.

METHODS

Observational, monocentric, retrospective study of critically ill patients receiving CI piperacillin-tazobactam, ceftazidime, or meropenem in monotherapy for documented Gram-negative infections optimized by means of a real-time TDM-guided strategy. Average steady-state beta-lactam concentrations (C ss ) were calculated for each patient, and the beta-lactam C ss /minimum inhibitory concentration (MIC) ratio was selected as a pharmacodynamic parameter of efficacy. The C ss /MIC ratio was defined as optimal if ≥4, quasi-optimal if between 1 and 4, and suboptimal if <1. The relationship between C ss /MIC and microbiological outcome was assessed.

RESULTS

Forty-six TDM assessments were carried out in 21 patients [median age 2 (interquartile range: 1-8) years]. C ss /MIC ratios were optimal in 76.2% of cases. Patients with optimal C ss /MIC ratios had both a significantly higher microbiological eradication rate (75.0% vs. 0.0%; P = 0.006) and lower resistance development rate (25.0% vs. 80.0%; P = 0.047) than those with quasi-optimal or suboptimal C ss /MIC ratios. Quasi-optimal/suboptimal C ss /MIC ratio occurred more frequently when patients had infections caused by pathogens with MIC values above the European Committee on Antimicrobial Susceptibility Testing clinical breakpoint (100.0% vs. 6.3%; P < 0.001).

CONCLUSIONS

Real-time TDM-guided pharmacodynamic target attainment of CI beta-lactam monotherapy allowed to maximize treatment efficacy in most critically ill children with severe Gram-negative infections. Attaining early optimal C ss /MIC ratios of CI beta-lactams could be a key determinant associated with microbiologic eradication during the treatment of Gram-negative infections. Larger prospective studies are warranted for confirming our findings.

Adequacy of cefepime concentrations in the early phase of critical illness: A case for precision pharmacotherapy

STUDY OBJECTIVE

In critically ill patients, adequacy of early antibiotic exposure has been incompletely evaluated. This study characterized factors associated with inadequate cefepime exposure in the first 24 h of critical illness.

DESIGN

Prospective cohort study.

SETTING

Academic Medical Center.

PATIENTS

Critically ill adults treated with cefepime. Patients with acute kidney injury or treated with kidney replacement therapy or extracorporeal membrane oxygenation were excluded.

INTERVENTION

None.

MEASUREMENTS

A nonlinear mixed-effects pharmacokinetic (PK) model was developed to estimate cefepime concentrations for each patient over time. The percentage of time the free drug concentration exceeded 8 mg/L during the first 24 h of therapy was calculated (%ƒT>8; appropriate for the susceptible breakpoint for Pseudomonas aeruginosa). Factors predictive of low %ƒT>8 were explored with multivariable regression.

MAIN RESULTS

In the 100 included patients, a one-compartment PK model was developed with first-order elimination with covariates for weight and estimated glomerular filtration rate based on creatinine and cystatin C (eGFRSCr-CysC). The median (interquartile range) %ƒT>8 for cefepime in the first 24 h of therapy based on this model was 85% (66%, 100%). Less than 100% ƒT>8 during first 24 h of therapy occurred in 70 (70%) individuals. Lower Sequential Organ Failure Assessment score (p = 0.032) and higher eGFRSCr-CysC (p < 0.001) predicted a lower %ƒT>8. Central nervous system infection source was protective (i.e., associated with a higher %ƒT>8; p = 0.008).

CONCLUSIONS

During early critical illness, cefepime concentrations were inadequate in a significant proportion of patients. Antimicrobial optimization is needed to improve the precision of pharmacotherapy in the critically ill patients.

Cefepime Daily Exposure and the Associated Impact on the Change in Sequential Organ Failure Assessment Scores and Vasopressors Requirement in Critically Ill Patients Using Repeated-Measures Mixed-Effect Modeling

IMPORTANCE

Sepsis and septic shock are major healthcare problems that need early and appropriate management.

OBJECTIVES

To evaluate the association of daily cefepime pharmacokinetic/pharmacodynamic (PK/PD) parameters with change in Sequential Organ Failure Assessment (SOFA) score and vasopressors requirement.

DESIGN SETTING AND PARTICIPANTS

This is a retrospective study. Adult ICU patients who received cefepime for Gram-negative pneumonia or bloodstream infection (BSI) and had cefepime concentrations measured were included. Daily cefepime exposure was generated and PK/PD parameters calculated for patients. Repeated-measures mixed-effect modeling was used to evaluate the impact of PK/PD on the outcomes.

MAIN OUTCOMES AND MEASURES

Change in daily SOFA score and vasopressors requirement.

RESULTS

A total of 394 and 207 patients were included in the SOFA and vasopressors analyses, respectively. The mean (±sd) age was 55 years (19) and weight 81 kg (29). For the change in SOFA score, daily SOFA score, mechanical ventilation, renal replacement therapy, and number of vasopressors were included. In the vasopressors analysis, daily SOFA score, day of therapy, and hydrocortisone dose were significant covariates in the final model. Achieving cefepime concentrations above the minimum inhibitory concentration (MIC) (T>MIC) for 100% of the dosing interval was associated with 0.006 µg/kg/min decrease in norepinephrine-equivalent dose. Cefepime PK/PD did not have an impact on the daily change in SOFA score.

CONCLUSIONS AND RELEVANCE

Achieving 100% T>MIC was associated with negligible decrease in vasopressors requirement in ICU patients with Gram-negative pneumonia and BSI. There was no impact on the change in SOFA score.

Loading dose plus continuous/extended infusion versus intermittent bolus of β-lactams for the treatment of Gram-negative bacteria bloodstream infections: a propensity score-adjusted retrospective cohort study

BACKGROUND

Optimal β-lactam dosing for the treatment of Gram-negative bacteria bloodstream infections (GNB-BSIs) remains a debated issue. Herein, the efficacy and safety of a loading dose (LD) followed by extended/continuous infusion (EI/CI) versus intermittent bolus (IB) of these drugs for the treatment of GNB-BSIs was evaluated.

METHODS

This is a retrospective observational study enrolling patients with GNB-BSIs treated with β-lactams from 1 October 2020 to 31 March 2022. The 30 day infection-related mortality rate was assessed with Cox regression, while mortality risk reduction was evaluated by an inverse probability of treatment weighting regression adjustment (IPTW-RA) model.

RESULTS

Overall, 224 patients were enrolled: 140 and 84 in the IB and EI/CI groups, respectively. β-Lactam regimens were chosen according to pathogen antibiogram, clinical judgement and current guidelines. Interestingly, the LD + EI/CI regimen was associated with a significant lower mortality rate (17% versus 32%, P = 0.011). Similarly, β-lactam LD + EI/CI was significantly associated with a reduced risk of mortality at multivariable Cox regression [adjusted HR (aHR) = 0.46; 95%CI = 0.22-0.98; P = 0.046]. Finally, the IPTW-RA (adjusted for multiple covariates) was performed, showing a significant risk reduction in the overall population [-14% (95% CI = -23% to -5%)]; at the subgroup restricted analysis, a significant risk reduction (>15%) was observed in the case of GNB-BSI in severely immunocompromised patients (P = 0.003), for SOFA score > 6 (P = 0.014) and in septic shock (P = 0.011).

CONCLUSIONS

The use of LD + EI/CI of β-lactams in patients with a GNB-BSI may be associated with reduced mortality; also in patients with severe presentation of infection or with additional risk factors, such as immunodepression.

Advances in antibacterial treatment of adults with high-risk febrile neutropenia

BACKGROUND

High-risk febrile neutropenia (HR-FN) is a life-threatening complication in patients with haematological malignancies or receiving myelosuppressive chemotherapy. Since the last international guidelines were published over 10 years ago, there have been major advances in the understanding and management of HR-FN, including on antibiotic pharmacokinetics and discontinuation/de-escalation strategies.

OBJECTIVES

Summarizing major advances in the field of antibacterial therapy in patients with HR-FN: empirical therapy, pharmacokinetics of antibiotics and antibiotic stewardship.

SOURCES

Narrative review based on literature review from PubMed. We focused on studies published between 2010 and 2023 about the pharmacokinetics of antimicrobials, management of antimicrobial administration, and discontinuation/de-escalation strategies. We did not address antimicrobial prophylaxis, viral or fungal infections.

CONTENT

Several high-quality publications have highlighted important modifications of antibiotic pharmacokinetics in HR-FN, with standard dosages exposing patients to underdosing. These recent clinical and population pharmacokinetics studies help improve management protocols with optimized initial dosing and infusion rules for β-lactams, vancomycin, daptomycin and amikacin; they highlight the potential benefits of therapeutic drug monitoring. A growing body of evidence also shows that antibiotic discontinuation/de-escalation strategies are beneficial for bacterial ecology and patients' outcome. We further discuss methods and limitations for implementation of such protocols in haematology.

IMPLICATIONS

We highlight recent information about the management of antibacterial therapy in HR-FN that might be considered in updated guidelines for HR-FN management.

International consensus recommendations for the use of prolonged-infusion beta-lactam antibiotics: Endorsed by the American College of Clinical Pharmacy, British Society for Antimicrobial Chemotherapy, Cystic Fibrosis Foundation, European Society of Clinical Microbiology and Infectious Diseases, Infectious Diseases Society of America, Society of Critical Care Medicine, and Society of Infectious Diseases Pharmacists

Intravenous β-lactam antibiotics remain a cornerstone in the management of bacterial infections due to their broad spectrum of activity and excellent tolerability. β-lactams are well established to display time-dependent bactericidal activity, where reductions in bacterial burden are directly associated with the time that free drug concentrations remain above the minimum inhibitory concentration (MIC) of the pathogen during the dosing interval. In an effort to take advantage of these bactericidal characteristics, prolonged (extended and continuous) infusions (PIs) can be applied during the administration of intravenous β-lactams to increase time above the MIC. PI dosing regimens have been implemented worldwide, but implementation is inconsistent. We report consensus therapeutic recommendations for the use of PI β-lactams developed by an expert international panel with representation from clinical pharmacy and medicine. This consensus guideline provides recommendations regarding pharmacokinetic and pharmacodynamic targets, therapeutic drug-monitoring considerations, and the use of PI β-lactam therapy in the following patient populations: severely ill and nonseverely ill adult patients, pediatric patients, and obese patients. These recommendations provide the first consensus guidance for the use of β-lactam therapy administered as PIs and have been reviewed and endorsed by the American College of Clinical Pharmacy (ACCP), the British Society for Antimicrobial Chemotherapy (BSAC), the Cystic Fibrosis Foundation (CFF), the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), the Infectious Diseases Society of America (IDSA), the Society of Critical Care Medicine (SCCM), and the Society of Infectious Diseases Pharmacists (SIDP).

Continuous vs Intermittent Meropenem Administration in Critically Ill Patients With Sepsis: The MERCY Randomized Clinical Trial

IMPORTANCE

Meropenem is a widely prescribed β-lactam antibiotic. Meropenem exhibits maximum pharmacodynamic efficacy when given by continuous infusion to deliver constant drug levels above the minimal inhibitory concentration. Compared with intermittent administration, continuous administration of meropenem may improve clinical outcomes.

OBJECTIVE

To determine whether continuous administration of meropenem reduces a composite of mortality and emergence of pandrug-resistant or extensively drug-resistant bacteria compared with intermittent administration in critically ill patients with sepsis.

DESIGN, SETTING, AND PARTICIPANTS

A double-blind, randomized clinical trial enrolling critically ill patients with sepsis or septic shock who had been prescribed meropenem by their treating clinicians at 31 intensive care units of 26 hospitals in 4 countries (Croatia, Italy, Kazakhstan, and Russia). Patients were enrolled between June 5, 2018, and August 9, 2022, and the final 90-day follow-up was completed in November 2022.

INTERVENTIONS

Patients were randomized to receive an equal dose of the antibiotic meropenem by either continuous administration (n = 303) or intermittent administration (n = 304).

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of all-cause mortality and emergence of pandrug-resistant or extensively drug-resistant bacteria at day 28. There were 4 secondary outcomes, including days alive and free from antibiotics at day 28, days alive and free from the intensive care unit at day 28, and all-cause mortality at day 90. Seizures, allergic reactions, and mortality were recorded as adverse events.

RESULTS

All 607 patients (mean age, 64 [SD, 15] years; 203 were women [33%]) were included in the measurement of the 28-day primary outcome and completed the 90-day mortality follow-up. The majority (369 patients, 61%) had septic shock. The median time from hospital admission to randomization was 9 days (IQR, 3-17 days) and the median duration of meropenem therapy was 11 days (IQR, 6-17 days). Only 1 crossover event was recorded. The primary outcome occurred in 142 patients (47%) in the continuous administration group and in 149 patients (49%) in the intermittent administration group (relative risk, 0.96 [95% CI, 0.81-1.13], P = .60). Of the 4 secondary outcomes, none was statistically significant. No adverse events of seizures or allergic reactions related to the study drug were reported. At 90 days, mortality was 42% both in the continuous administration group (127 of 303 patients) and in the intermittent administration group (127 of 304 patients).

CONCLUSIONS AND RELEVANCE

In critically ill patients with sepsis, compared with intermittent administration, the continuous administration of meropenem did not improve the composite outcome of mortality and emergence of pandrug-resistant or extensively drug-resistant bacteria at day 28.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03452839.

Meropenem Pharmacokinetics and Target Attainment in Critically Ill Patients

Purpose

This study aimed to investigate the pharmacokinetics and target attainment of meropenem and compare the effect of meropenem dosing regimens in critically ill patients.

Patients and Methods

Thirty-seven critically ill patients who were administered meropenem in intensive care units were analyzed. Patients were classified according to their renal function. Pharmacokinetic parameters were assessed based on Bayesian estimation. The target attainment of 40%fT > MIC (fraction time that the free concentration exceeds the minimum inhibitory concentration) and 100%fT > MIC with the pathogen MIC of 2 mg/L and 8 mg/L were specially focused. Furthermore, the effects of standard dosing (1g meropenem, 30 min intravenous infusion every 8h) and non-standard dosing (dosage regimens except standard dosing) were compared.

Results

The results showed that the values of meropenem clearance (CL), central volume of distribution (V1), intercompartmental clearance (Q), and peripheral volume of distribution (V2) were 3.3 L/h, 9.2 L, 20.1 L/h and 12.8 L, respectively. The CL of the patients among renal function groups was significantly different (p < 0.001). The tow targets attainment for the pathogen MIC of 2 mg/L and 8 mg/L were 89%, 73%, 49% and 27%, respectively. The severe renal impairment group has higher fraction of target attainment than the other group. The standard dosing achieved the target of 40%fT > 2/8 mg/L (85.7% and 81%, respectively) and patients with severe renal impairment achieved the target fraction of 100% for 40%fT > MIC. Additionally, there was no significant difference between standard and non-standard dosing group in target attainment.

Conclusion

Our findings indicate that renal function is an important covariate for both meropenem pharmacokinetics parameters and target attainment. The target attainment between standard and non-standard dosing group was not comparable. Therefore, therapeutic drug monitoring is indispensable in the dosing adjustment for critically ill patients if it is available.

Optimizing Betalactam Clinical Response by Using a Continuous Infusion: A Comprehensive Review

INTRODUCTION

Antimicrobial resistance is a major healthcare issue responsible for a large number of deaths. Many reviews identified that PKPD data are in favor of the use of continuous infusion, and we wanted to review clinical data results in order to optimize our clinical practice.

METHODOLOGY

We reviewed Medline for existing literature comparing continuous or extended infusion to intermittent infusion of betalactams.

RESULTS

In clinical studies, continuous infusion is as good as intermittent infusion. In the subset group of critically ill patients or those with an infection due to an organism with high MIC, a continuous infusion was associated with better clinical response.

CONCLUSIONS

Clinical data appear to confirm those of PK/PD to use a continuous infusion in severely ill patients or those infected by an organism with an elevated MIC, as it is associated with higher survival rates. In other cases, it may allow for a decrease in antibiotic daily dosage, thereby contributing to a decrease in overall costs.

Extended and Continuous Infusion of Novel Protected β-Lactam Antibiotics: A Narrative Review

Consolidated data from pharmacokinetic and pharmacodynamic studies support the administration of β-lactam antibiotics in prolonged infusion (i.e., extended or continuous) to optimize therapeutic efficacy by increasing the probability of attaining maximal bactericidal activity. This is the longest possible time during which the free drug concentrations are approximately four-fold the minimum inhibitory concentration between dosing intervals. In the context of antimicrobial stewardship strategies, achieving aggressive pharmacokinetic and pharmacodynamic targets is an important tool in the management of multi-drug resistant (MDR) bacterial infections and in the attainment of mutant preventing concentrations. However, prolonged infusion remains an unexploited resource. Novel β-lactam/β-lactamase inhibitor (βL/βLI) combinations (ceftolozane-tazobactam, ceftazidime-avibactam, meropenem-vaborbactam, and imipenem-cilastatin-relebactam) have been released in recent years to face the emerging challenge of MDR Gram-negative bacteria. Pre-clinical and real-life evidence has confirmed the promising role of prolonged infusion of these molecules in specific settings and clinical populations. In this narrative review we have summarized available pharmacological and clinical data, future perspectives, and current limitations of prolonged infusion of the novel protected β-lactams, their application in hospital settings and in the context of outpatient parenteral antimicrobial therapy.

Efficacy of drug treatment for severe melioidosis and eradication treatment of melioidosis: A systematic review and network meta-analysis

BACKGROUND

This systematic review and network meta-analysis (NMA) aimed to compare the efficacy of all available treatments for severe melioidosis in decreasing hospital mortality and to identify eradication therapies with low disease recurrence rates and minimal risk of adverse drug events (AEs).

METHODOLOGY

Relevant randomized controlled trials (RCT) were searched from Medline and Scopus databases from their inception until July 31, 2022. RCTs that compared the efficacy between treatment regimens for severe melioidosis or eradication therapy of melioidosis, measured outcomes of in-hospital mortality, disease recurrence, drug discontinuation, or AEs, were included for review. A two-stage NMA with the surface under the cumulative ranking curve (SUCRA) was used to estimate the comparative efficacy of treatment regimens.

PRINCIPAL FINDINGS

Fourteen RCTs were included in the review. Ceftazidime plus granulocyte colony-stimulating factor (G-CSF), ceftazidime plus trimethoprim-sulfamethoxazole (TMP-SMX), and cefoperazone-sulbactam plus TMP-SMX had a lower mortality rate than other treatments and were ranked as the top three most appropriate treatments for severe melioidosis with the SUCRA of 79.7%, 66.6%, and 55.7%, respectively. However, these results were not statistically significant. For eradication therapy, treatment with doxycycline monotherapy for 20 weeks was associated with a significantly higher risk of disease recurrence than regimens containing TMP-SMX (i.e.,TMP-SMX for 20 weeks, TMP-SMX plus doxycycline plus chloramphenicol for more than 12 weeks, and TMP-SMX plus doxycycline for more than 12 weeks). According to the SUCRA, TMP-SMX for 20 weeks was ranked as the most efficacious eradication treatment (87.7%) with the lowest chance of drug discontinuation (86.4%), while TMP-SMX for 12 weeks had the lowest risk of AEs (95.6%).

CONCLUSION

Our results found a non-significant benefit of ceftazidime plus G-CSF and ceftazidime plus TMP-SMX over other treatments for severe melioidosis. TMP-SMX for 20 weeks was associated with a lower recurrence rate and minimal risk of adverse drug events compared to other eradication treatments. However, the validity of our NMA may be compromised by the limited number of included studies and discrepancies in certain study parameters. Thus, additional well-designed RCTs are needed to improve the therapy of melioidosis.

Population Pharmacokinetic Model and Dosing Simulation of Meropenem Using Measured Creatinine Clearance for Patients with Sepsis

PURPOSE

Creatinine clearance (CCr) and pharmacokinetic parameters are markedly affected by pathophysiological changes in patients with sepsis. However, only a few reports have assessed renal function in patients with sepsis using the measured CCr. Furthermore, the administration regimen has not been sufficiently evaluated using a population PK (PPK) model across renal function broad ranges. Therefore, this study was performed to construct a meropenem PPK model for patients with sepsis using the measured CCr and evaluate the optimized meropenem dosing regimen based on the CCr.

METHODS

Patients with sepsis who received intravenous meropenem at the Showa University Hospital were enrolled in this prospective observational study. The PPK model was constructed using blood samples and clinical information of patients. The probability of target attainment (PTA) indicates the likelihood of achieving 50% time above the minimum inhibitory concentration (% T > MIC) based on 10,000 virtual patients using Monte Carlo simulations. The PTA for each meropenem regimen was 50% T > MIC based on different renal functions using the Monte Carlo simulation.

RESULTS

One hundred samples were collected from 31 patients. The final PPK model incorporating the measured CCr as a covariate in CL displayed the best fit. The recommended dosing regimen to achieve a PTA of 50% T > MIC of 4 mcg/mL was 1 g every 8 hours as a 3-hour prolonged infusion for patients with CCr 85-130 mL/min and 1 g every 8 hours as an 8-hour continuous infusion for patients with CCr ≥ 130 mL/min.

CONCLUSIONS

This model precisely predicted meropenem concentrations in patients with sepsis by accurately evaluating renal function using the measured CCr. Extended dosing was demonstrated to be necessary to achieve a PTA of 50% T > MIC for patients with CCr ≥ 85 mL/min. Meropenem effectiveness can be maximized in patients with sepsis by selecting the appropriate dosing regimen based on renal function and the MIC.

Sustaining Life versus Altering Life-Saving Drugs: Insights to Explain the Paradoxical Effect of Extracorporeal Membrane Oxygenation on Drugs

There has been a substantial increase in the use of extracorporeal membrane oxygenation (ECMO) support in critically ill adults. Understanding the complex changes that could affect drugs' pharmacokinetics (PK) and pharmacodynamics (PD) is of suitable need. Therefore, critically ill patients on ECMO represent a challenging clinical situation to manage pharmacotherapy. Thus, clinicians' ability to predict PK and PD alterations within this complex clinical context is fundamental to ensure further optimal and, sometimes, individualized therapeutic plans that balance clinical outcomes with the minimum drug adverse events. Although ECMO remains an irreplaceable extracorporeal technology, and despite the resurgence in its use for respiratory and cardiac failures, especially in the era of the COVID-19 pandemic, scarce data exist on both its effect on the most commonly used drugs and their relative management to achieve the best therapeutic outcomes. The goal of this review is to provide key information about some evidence-based PK alterations of the drugs used in an ECMO setting and their monitoring.

Clinical efficacy and safety of prolonged versus intermittent administration of antipseudomonal beta-lactam antibiotics in adults with severe acute infections: A meta-analysis of randomized controlled trials

INTRODUCTION

In order to compare the clinical efficacy and safety of prolonged versus intermittent antipseudomonal beta-lactam antibiotic infusion for the treatment of severe acute infections in adult patients, a meta-analysis of randomized controlled trials (RCTs) was performed.

METHODS

We systematically searched MEDLINE and Cochrane Library databases until December 2022. The outcomes were all-cause mortality, clinical success, microbiological eradication and adverse events. The pooled risk ratios (RR) were estimated by the fixed or random effect methods according to heterogeneity statistics. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to evaluate the certainty of evidence for each outcome.

RESULTS

Twenty eligible RCTs with 2081 participants were included in the meta-analysis. The risk of all-cause mortality was significantly lower in the prolonged infusion group than in the intermittent infusion group (RR 0.77, 95% confidence interval [CI] 0.63-0.95, p = 0.01, I² = 0%; moderate certainty). Treatment with prolonged infusion showed significant benefit in clinical success (RR 1.09, 95% CI 1.02-1.17, p = 0.008, I² = 19%; moderate certainty). There were no significant differences in microbiological eradication (RR 1.12, 95% CI 0.99-1.28, p = 0.07, I² = 49%; low certainty), any adverse events (RR 0.96, 95% CI 0.86-1.08, p = 0.50, I² = 27%; moderate certainty) and serious adverse events (RR 0.99, 95%CI 0.70-1.39 p = 0.95, I² = 0%; low certainty).

CONCLUSIONS

Prolonged antipseudomonal beta-lactam infusion probably decreases all-cause mortality. Additionally, it probably increases clinical success in adults with severe acute infections. This infusion strategy may result in little to no difference in microbiological eradication and is probably not associated with a rise in any adverse events.The evidence suggests that prolonged infusion may not increase serious adverse events.

Emerging concepts in the care of patients with cirrhosis and septic shock

Septic shock impacts approximately 6% of hospitalized patients with cirrhosis and is associated with high rates of morbidity and mortality. Although a number of landmark clinical trials have paved the way for incremental improvements in the diagnosis and management of septic shock in the general population, patients with cirrhosis have largely been excluded from these studies and critical knowledge gaps continue to impact the care of these individuals. In this review, we discuss nuances in the care of patients with cirrhosis and septic shock using a pathophysiology-based approach. We illustrate that septic shock may be challenging to diagnose in this population in the context of factors such as chronic hypotension, impaired lactate metabolism, and concomitant hepatic encephalopathy. Furthermore, we demonstrate that the application of routine interventions such as intravenous fluids, vasopressors, antibiotics, and steroids should be carefully considered among those with decompensated cirrhosis in light of hemodynamic, metabolic, hormonal, and immunologic disturbances. We propose that future research should include and characterize patients with cirrhosis in a systematic manner, and clinical practice guidelines may need to be refined accordingly.

Continuous infusion of beta-lactam antibiotics: narrative review of systematic reviews, and implications for outpatient parenteral antibiotic therapy

INTRODUCTION

Continuous infusion (CI) of beta-lactam antibiotics may be of benefit in some patients, particularly those with severe infections. However, most studies have been small and conflicting results have been reported. The best available evidence on clinical outcomes of beta-lactam CI comes from systematic reviews/meta-analyses that integrate the available data.

AREAS COVERED

A search of PubMed from inception to the end of February 2022 for systematic reviews of clinical outcomes with beta-lactam CI for any indication identified 12 reviews, all of which focused on hospitalized patients, most of whom were critically ill. A narrative overview of these systematic reviews/meta-analyses is provided. No systematic reviews evaluating the use of beta-lactam CI for outpatient parenteral antibiotic therapy (OPAT) were identified, as few studies have focused on this area. Relevant data are summarized, and consideration is given to issues that need to be addressed when using beta-lactam CI in the setting of OPAT.

EXPERT OPINION

Evidence from systematic reviews supports a role for beta-lactam CI in the treatment of hospitalized patients with severe/life-threatening infections. Beta-lactam CI can play a role in patients receiving OPAT for severe chronic/difficult-to-treat infections, but additional data are needed to clarify its optimal use.

Update on Therapeutic Drug Monitoring of Beta-Lactam Antibiotics in Critically Ill Patients—A Narrative Review

Beta-lactam antibiotics remain one of the most preferred groups of antibiotics in critical care due to their excellent safety profiles and their activity against a wide spectrum of pathogens. The cornerstone of appropriate therapy with beta-lactams is to achieve an adequate plasmatic concentration of a given antibiotic, which is derived primarily from the minimum inhibitory concentration (MIC) of the specific pathogen. In a critically ill patient, the plasmatic levels of drugs could be affected by many significant changes in the patient’s physiology, such as hypoalbuminemia, endothelial dysfunction with the leakage of intravascular fluid into interstitial space and acute kidney injury. Predicting antibiotic concentration from models based on non-critically ill populations may be misleading. Therapeutic drug monitoring (TDM) has been shown to be effective in achieving adequate concentrations of many drugs, including beta-lactam antibiotics. Reliable methods, such as high-performance liquid chromatography, provide the accurate testing of a wide range of beta-lactam antibiotics. Long turnaround times remain the main drawback limiting their widespread use, although progress has been made recently in the implementation of different novel methods of antibiotic testing. However, whether the TDM approach can effectively improve clinically relevant patient outcomes must be proved in future clinical trials.

Predictive Factors of Piperacillin Exposure and the Impact on Target Attainment after Continuous Infusion Administration to Critically Ill Patients

Critically ill patients undergo significant pathophysiological changes that affect antibiotic pharmacokinetics. Piperacillin/tazobactam administered by continuous infusion (CI) improves pharmacokinetic/pharmacodynamic (PK/PD) target attainment. This study aimed to characterize piperacillin PK after CI administration of piperacillin/tazobactam in critically ill adult patients with preserved renal function and to determine the empirical optimal dosing regimen. A total of 218 piperacillin concentrations from 106 patients were simultaneously analyzed through the population PK approach. A two-compartment linear model best described the data. Creatinine clearance (CL_CR) estimated by CKD-EPI was the covariate, the most predictive factor of piperacillin clearance (CL) interindividual variability. The mean (relative standard error) parameter estimates for the final model were: CL: 12.0 L/h (6.03%); central and peripheral compartment distribution volumes: 20.7 L (8.94%) and 62.4 L (50.80%), respectively; intercompartmental clearance: 4.8 L/h (26.4%). For the PK/PD target of 100% fT_>1×MIC, 12 g of piperacillin provide a probability of target attainment > 90% for MIC < 16 mg/L, regardless of CL_CR, but higher doses are needed for MIC = 16 mg/L when CL_CR > 100 mL/min. For 100% fT_>4×MIC, the highest dose (24 g/24 h) was not sufficient to ensure adequate exposure, except for MICs of 1 and 4 mg/L. Our model can be used as a support tool for initial dose guidance and during therapeutic drug monitoring.

The Influence of Extracorporeal Membrane Oxygenation on Antibiotic Pharmacokinetics

Extracorporeal membrane oxygenation (ECMO) is becoming increasingly utilized to support critically ill patients who experience life-threatening cardiac or pulmonary compromise. The provision of this intervention poses challenges related to its complications and the optimization of medication therapy. ECMO's mechanical circulatory support is facilitated via various devices and equipment that have been shown to sequester lipophilic- and protein-bound medications, including anti-infectives. Since infectious outcomes are dependent on achieving specific anti-infectives' pharmacodynamic targets, the understanding of these medications' pharmacokinetic parameters in the setting of ECMO is important to clinicians. This narrative, non-systematic review evaluated the findings of the most recent and robust pharmacokinetic analyses for commonly utilized anti-infectives in the setting of ECMO. The data from available literature indicates that anti-infective pharmacokinetic parameters are similar to those observed in other non-ECMO critically ill populations, but considerable variability in the findings was observed between patients, thus prompting further evaluation of therapeutic drug monitoring in this complex population.

Optimizing antibiotic dosing regimens for nosocomial pneumonia: a window of opportunity for pharmacokinetic and pharmacodynamic modeling

INTRODUCTION

Determining antibiotic exposure in the lung and the threshold(s) needed for effective antibacterial killing is paramount during development of new antibiotics for the treatment of nosocomial pneumonia, as these exposures directly affect clinical outcomes and resistance development. The use of pharmacokinetic and pharmacodynamic modeling is recommended by regulatory agencies to evaluate antibiotic pulmonary exposure and optimize dosage regimen selection. This process has been implemented in newer antibiotic development.

AREAS COVERED

This review will discuss the basis for conducting pharmacokinetic and pharmacodynamic studies to support dosage regimen selection and optimization for the treatment of nosocomial pneumonia. Pharmacokinetic/pharmacodynamic data that supported recent hospital-acquired bacterial pneumonia/ventilator-associated bacterial pneumonia indications for ceftolozane/tazobactam, ceftazidime/avibactam, imipenem/cilastatin/relebactam, and cefiderocol will be reviewed.

EXPERT OPINION

Optimal drug development requires the integration of preclinical pharmacodynamic studies, healthy volunteers and ideally patient bronchoalveolar lavage pharmacokinetic studies, Monte-Carlo simulation, and clinical trials. Currently, plasma exposure has been successfully used as a surrogate for lung exposure threshold. Future studies are needed to identify the value of lung pharmacodynamic thresholds in nosocomial pneumonia antibiotic dosage optimization.

The clinical and paraclinical effectiveness of four-hour infusion vs. half-hour infusion of high-dose ampicillin-sulbactam in treatment of critically ill patients with sepsis or septic shock: An assessor-blinded randomized clinical trial

PURPOSE

This study was conducted to determine whether critically ill patients admitted to the intensive care unit (ICU) with sepsis and septic shock may benefit from extended infusion of ampicillin/sulbactam compared with those receiving intermittent infusion.

MATERIAL AND METHODS

This randomized assessor-blinded clinical trial was conducted in the ICUs of Nemazee and Shahid Rajaee hospital, Shiraz, Iran, from August 2019 to August 2021. The participants randomly received 9 g Ampicillin/Sulbactam every 8 h by either extended (infused over 4 h) or intermittent (infused over 30 min) intravenous infusion if their estimated glomerular filtration rate based on Cockrorft-Gault formula was higher than 60 ml/min.

RESULTS

Totally, 136 patients were enrolled and allocated to the intervention and control groups, each with 68 patients. Clinical cure was significantly higher in the extended group (P = 0.039), but ICU and hospital length of stay did not differ between the groups (P = 0.87 and 0.83, respectively). The ICU (P = 0.031) and hospital (P = 0.037) mortality rates in the extended infusion group were significantly lower than those in the intermittent infusion group.

CONCLUSION

These data should be replicated in larger clinical trials before providing any recommendation in favor of this method of administration in clinical practice.

Continuous Infusion of High Doses of Cefepime in Intensive Care Unit: Assessment of Steady-State Plasma Level and Incidence on Neurotoxicity

Continuous infusion (CI) with high doses of cefepime is recommended in the empirical antimicrobial regimen of critically ill patients with suspected Gram-negative sepsis. This study aimed to determine factors associated with cefepime overdosing and the incidence of cefepime-induced neurotoxicity (CIN) in these patients. We performed a retrospective study including all patients receiving cefepime treatment between January 2019 and May 2022. The plasma level of cefepime defining overdosing was over 35 mg/L. Neurotoxicity was defined according to strict criteria and correlated with concomitant steady-state concentration of cefepime. Seventy-eight courses of cefepime treatment were analyzed. The mean cefepime plasma level at steady state was 59.8 ± 29.3 mg/L, and overdosing occurred in 80% of patients. Renal failure and a daily dose > 5 g were independently associated with overdosing. CIN was present in 30% of patients. In multivariate analysis, factors associated with CIN were chronic renal failure and a cefepime plasma concentration ≥ 60 mg/L. CIN was not associated with mortality. Overdosing is frequent in patients receiving high doses of cefepime by CI. Steady-state levels are higher than targeted therapeutic pharmacokinetic/pharmacodynamic objectives. The risk of CIN is important when the plasma concentration is ≥60 mg/L.

β-lactam precision dosing in critically ill children: Current state and knowledge gaps

There has been emerging interest in implementing therapeutic drug monitoring and model-informed precision dosing of β-lactam antibiotics in critically ill patients, including children. Despite a position paper endorsed by multiple international societies that support these efforts in critically ill adults, implementation of β-lactam precision dosing has not been widely adopted. In this review, we highlight what is known about β-lactam antibiotic pharmacokinetics and pharmacodynamics in critically ill children. We also define the knowledge gaps that present barriers to acceptance and implementation of precision dosing of β-lactam antibiotics in critically ill children: a lack of consensus on which subpopulations would benefit most from precision dosing and the uncertainty of how precision dosing changes outcomes. We conclude with opportunities for further research to close these knowledge gaps.

Major Publications in the Critical Care Pharmacotherapy Literature: 2021

To summarize the most impactful articles relevant to the pharmacotherapy of critically ill adult patients published in 2021.

DATA SOURCE

PubMed/MEDLINE.

STUDY SELECTION

Randomized controlled trials, prospective studies, or systematic review/meta-analyses of adult critical care patients assessing a pharmacotherapeutic intervention and reporting clinical endpoints published between January 1, 2021, and December 31, 2021.

DATA EXTRACTION

Candidate articles were organized by clinical domain based on the emerging themes from all studies. A modified Delphi process was applied to obtain consensus on the most impactful publication within each clinical domain based on overall contribution to scientific knowledge and novelty to the literature.

DATA SYNTHESIS

The search revealed 830 articles, of which 766 were excluded leaving 64 candidate articles for the Delphi process. These 64 articles were organized by clinical domain including: emergency/neurology, cardiopulmonary, nephrology/fluids, infectious diseases, metabolic, immunomodulation, and nutrition/gastroenterology. Each domain required the a priori defined three Delphi rounds. The resultant most impactful articles from each domain included five randomized controlled trials and two systematic review/meta-analyses. Topics studied included sedation during mechanical ventilation, anticoagulation in COVID-19, extended infusion beta-lactams, interleukin-6 antagonists in COVID-19, balanced crystalloid resuscitation, vitamin C/thiamine/hydrocortisone in sepsis, and promotility agents during enteral feeding.

CONCLUSIONS

This synoptic review provides a summary and perspective of the most impactful articles relevant to the pharmacotherapy of critically ill adults published in 2021.

Empirical Antibiotic Therapy for Gram-Negative Bacilli Ventilator-Associated Pneumonia: Observational Study and Pharmacodynamic Assessment

Background: Strong evidence suggests a correlation between pharmacodynamics (PD) index and antibiotic efficacy while dose adjustment should be considered in critically ill patients due to modified pharmacokinetic (PK) parameters and/or higher minimum inhibitory concentrations (MICs). This study aimed to assess pharmacodynamic (PD) target attainment considering both antibiotics serum concentrations and measured MICs in these patients. Method: A multicentric prospective open-label trial conducted in 11 French ICUs involved patients with Gram-negative bacilli (GNB) ventilator-associated pneumonia (VAP) confirmed by quantitative cultures. Results: We included 117 patients. Causative GNBs were P. aeruginosa (40%), Enterobacter spp. (23%), E. coli (20%), and Klebsiella spp. (16%). Hence, 117 (100%) patients received β-lactams, 65 (58%) aminoglycosides, and two (1.5%) fluoroquinolones. For β-lactams, 83% of the patients achieved a Cmin/MIC > 1 and 70% had a Cmin/MIC > 4. In the case of high creatinine clearance (CrCL > 100 mL/min/1.73 m2), 70.4% of the patients achieved a Cmin/MIC ratio > 1 versus 91% otherwise (p = 0.041), and 52% achieved a Cmin/MIC ratio > 4 versus 81% (p = 0.018). For aminoglycosides, 94% of the patients had a Cmax/MIC ratio > 8. Neither β-lactams nor aminoglycosides PK/PD parameters were associated clinical outcomes, but our data suggest a correlation between β-lactams Cmin/MIC and microbiological success. Conclusion: In our ICU patients treated for GNB VAP, using recommended antibiotic dosage led in most cases to PK/PD targets attainment for aminoglycosides and β-lactams. High creatinine clearance should encourage clinicians to focus on PK/PD issues.