Year in review in Intensive Care Medicine 2013: III. Sepsis, infections, respiratory diseases, pediatrics

Performance and economic evaluation of the molecular detection of pathogens for patients with severe infections: the EVAMICA open-label, cluster-randomised, interventional crossover trial

Purpose

Microbiological diagnosis (MD) of infections remains insufficient. The resulting empirical antimicrobial therapy leads to multidrug resistance and inappropriate treatments. We therefore evaluated the cost-effectiveness of direct molecular detection of pathogens in blood for patients with severe sepsis (SES), febrile neutropenia (FN) and suspected infective endocarditis (SIE).

Methods

Patients were enrolled in a multicentre, open-label, cluster-randomised crossover trial conducted during two consecutive periods, randomly assigned as control period (CP; standard diagnostic workup) or intervention period (IP; additional testing with LightCycler^®SeptiFast). Multilevel models used to account for clustering were stratified by clinical setting (SES, FN, SIE).

Results

A total of 1416 patients (907 SES, 440 FN, 69 SIE) were evaluated for the primary endpoint (rate of blood MD). For SES patients, the MD rate was higher during IP than during CP [42.6% (198/465) vs. 28.1% (125/442), odds ratio (OR) 1.89, 95% confidence interval (CI) 1.43–2.50; P < 0.001], with an absolute increase of 14.5% (95% CI 8.4–20.7). A trend towards an association was observed for SIE [35.4% (17/48) vs. 9.5% (2/21); OR 6.22 (0.98–39.6)], but not for FN [32.1% (70/218) vs. 30.2% (67/222), P = 0.66]. Overall, turn-around time was shorter during IP than during CP (22.9 vs. 49.5 h, P < 0.001) and hospital costs were similar (median, mean ± SD: IP €14,826, €18,118 ± 17,775; CP €17,828, €18,653 ± 15,966). Bootstrap analysis of the incremental cost-effectiveness ratio showed weak dominance of intervention in SES patients.

Conclusion

Addition of molecular detection to standard care improves MD and thus efficiency of healthcare resource usage in patients with SES.

ClinicalTrials.gov registration number: NCT00709358.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-017-4766-4) contains supplementary material, which is available to authorized users.

Ventilator-associated pneumonia in ARDS patients: the impact of prone positioning. A secondary analysis of the PROSEVA trial

BACKGROUND

The goal of this study was to assess the impact of prone positioning on the incidence of ventilator-associated pneumonia (VAP) and the role of VAP in mortality in a recent multicenter trial performed on patients with severe ARDS.

METHODS

An ancillary study of a prospective multicenter randomized controlled trial on early prone positioning in patients with severe ARDS. In suspected cases of VAP the diagnosis was based on positive quantitative cultures of bronchoalveolar lavage fluid or tracheal aspirate at the 10(4) and 10(7) CFU/ml thresholds, respectively. The VAP cases were then subject to central, independent adjudication. The cumulative probabilities of VAP were estimated in each position group using the Aalen-Johansen estimator and compared using Gray's test. A univariate and a multivariate Cox model was performed to assess the impact of VAP, used as a time-dependent covariate for mortality hazard during the ICU stay.

RESULTS

In the supine and prone position groups, the incidence rate for VAP was 1.18 (0.86-1.60) and 1.54 (1.15-2.02) per 100 days of invasive mechanical ventilation (p = 0.10), respectively. The cumulative probability of VAP at 90 days was estimated at 46.5 % (27-66) in the prone group and at 33.5 % (23-44) in the supine group. The difference between the two cumulative probability curves was not statistically significant (p = 0.11). In the univariate Cox model, VAP was associated with an increase in the mortality rate during the ICU stay [HR 1.65 (1.05-2.61), p = 0.03]. HR increased to 2.2 (1.39-3.52) (p < 0.001) after adjustment for position group, age, SOFA score, McCabe score, and immunodeficiency.

CONCLUSIONS

In severe ARDS patients prone positioning did not reduce the incidence of VAP and VAP was associated with higher mortality.

Early fluid accumulation in children with shock and ICU mortality: a matched case-control study

PURPOSE

The purpose of this study was to evaluate the association between early fluid accumulation and mortality in children with shock states.

METHODS

We retrospectively reviewed children admitted in shock states to the pediatric intensive care unit (ICU) at a tertiary level children's hospital over a 7-month period. The study was designed as a matched case-control study. Children with early fluid overload, defined as fluid accumulation of ≥10% of admission body weight during the initial 3 days, were designated as the cases. They were compared with matched controls without early fluid accumulation. Cases and controls were matched for age, severity of illness at ICU admission and need for organ support. They were compared with respect to all-cause ICU mortality and other secondary outcomes.

RESULTS

A total of 114 children (age range 0-17.4 years; N = 42 cases and 72 matched controls) met the study criteria. Mortality rate was 13% (15/114) in this cohort. Multivariable logistic regression analysis identified the presence of early fluid overload [adjusted odds ratio (OR) 9.17, 95% confidence interval (CI) 2.22-55.57], its severity (adjusted OR 1.11, 95% CI 1.05-1.19) and its duration (adjusted OR 1.61, 95% CI 1.21-2.28) as independent predictors of mortality. Cases had higher mortality than the controls (26 vs. 6 %; p 0.003), and this difference remained significant in the matched analysis (37 vs. 3%; p 0.002).

CONCLUSION

The presence, severity and duration of early fluid are associated with increased ICU mortality in children admitted to the pediatric ICU in shock states.

Feasibility and utility of the use of real time random safety audits in adult ICU patients: a multicentre study

PURPOSE

The two aims of this study were first to analyse the feasibility and utility (to improve the care process) of implementing a new real time random safety tool and second to explore the efficacy of this tool in core hospitals (those participating in tool design) versus non-core hospitals.

METHODS

This was a prospective study conducted over a period of 4 months in six adult intensive care units (two of which were core hospitals). Safety audits were conducted 3 days per week during the entire study period to determine the efficacy of the 37 safety measures (grouped into ten blocks). In each audit, 50% of patients and 50% of measures were randomized. Feasibility was calculated as the proportion of audits completed over those scheduled and time spent, and utility was defined as the changes in the care process resulting from tool application.

RESULTS

A total of 1323 patient-days were analysed. In terms of feasibility, 87.6% of the scheduled audits were completed. The average time spent per audit was 34.5 ± 29 min. Globally, changes in the care process occurred in 5.4% of the measures analysed. In core hospitals, utility was significantly higher in 16 of the 37 measures, all of which were included in good clinical practice guidelines. Most of the clinical changes brought about by the tool occurred in the mechanical ventilation and haemodynamics blocks. Multivariate analyses demonstrated that changes in the care process in each block were associated with the core hospital variable, staffing ratios and severity of patient disease.

CONCLUSIONS

Real time safety audits improved the care process and adherence to the clinical practice guidelines and proved to be most useful in situations of high care load and in patients with more severe disease. The effect was greater in core hospitals.

Risk factors for target non-attainment during empirical treatment with β-lactam antibiotics in critically ill patients

PURPOSE

Risk factors for β-lactam antibiotic underdosing in critically ill patients have not been described in large-scale studies. The objective of this study was to describe pharmacokinetic/pharmacodynamic (PK/PD) target non-attainment envisioning empirical dosing in critically ill patients and considering a worst-case scenario as well as to identify patient characteristics that are associated with target non-attainment.

METHODS

This analysis uses data from the DALI study, a prospective, multi-centre pharmacokinetic point-prevalence study. For this analysis, we assumed that these were the concentrations that would be reached during empirical dosing, and calculated target attainment using a hypothetical target minimum inhibitory concentration (MIC), namely the susceptibility breakpoint of the least susceptible organism for which that antibiotic is commonly used. PK/PD targets were free drug concentration maintained above the MIC of the suspected pathogen for at least 50 % and 100 % of the dosing interval respectively (50 % and 100 % f T (>MIC)). Multivariable analysis was performed to identify factors associated with inadequate antibiotic exposure.

RESULTS

A total of 343 critically ill patients receiving eight different β-lactam antibiotics were included. The median (interquartile range) age was 60 (47-73) years, APACHE II score was 18 (13-24). In the hypothetical situation of empirical dosing, antibiotic concentrations remained below the MIC during 50 % and 100 % of the dosing interval in 66 (19.2 %) and 142 (41.4 %) patients respectively. The use of intermittent infusion was significantly associated with increased risk of non-attainment for both targets; creatinine clearance was independently associated with not reaching the 100 % f T( >MIC) target.

CONCLUSIONS

This study found that-in empirical dosing and considering a worst--case scenario--19 % and 41 % of the patients would not achieve antibiotic concentrations above the MIC during 50 % and 100 % of the dosing interval. The use of intermittent infusion (compared to extended and continuous infusion) was the main determinant of non-attainment for both targets; increasing creatinine clearance was also associated with not attaining concentrations above the MIC for the whole dosing interval. In the light of this study from 68 ICUs across ten countries, we believe current empiric dosing recommendations for ICU patients are inadequate to effectively cover a broad range of susceptible organisms and need to be reconsidered.