[Pharmacokinetics and pharmacodynamics of antibiotic therapy]

[Epidemiology, diagnosis and treatment of adult patients with nosocomial pneumonia]

BACKGROUND

 Nosocomial pneumonia, encompassing hospital-acquired (HAP) and ventilator-associated pneumonia (VAP), remains a major cause of morbidity and mortality in hospitalized adults. In response to evolving pathogen profiles and emerging resistance patterns, this updated S3 guideline (AWMF Register No. 020-013) provides an evidence-based framework to enhance the diagnosis, risk stratification, and treatment of nosocomial pneumonia.

METHODS

 The guideline update was developed by a multidisciplinary panel representing key German professional societies. A systematic literature review was conducted with subsequent critical appraisal using the GRADE methodology. Structured consensus conferences and external reviews ensured that the recommendations were clinically relevant, methodologically sound, and aligned with current antimicrobial stewardship principles.

RESULTS

 For the management of nosocomial pneumonia patients should be divided in those with and without risk factors for multidrug-resistant pathogens and/or Pseudomonas aeruginosa. Bacterial multiplex-polymerase chain reaction (PCR) should not be used routinely. Bronchoscopic diagnosis is not considered superior to non-bronchoscopic sampling in terms of main outcomes. Combination antibiotic therapy is now reserved for patients in septic shock and high risk for multidrug-resistant pathogens, while select patients may be managed with monotherapy (e. g., meropenem). In clinically stabilized patients, antibiotic therapy should be de-escalated and focused, as well as duration shortened to 7-8 days. In critically ill patients, prolonged application of suitable beta-lactam antibiotics should be preferred. Patients on the intensive care unit (ICU) are at risk for invasive pulmonary aspergillosis (IPA). Diagnostics for Aspergillus should be performed with an antigen test from bronchial lavage fluid.

CONCLUSION

 This updated S3 guideline offers a comprehensive, multidisciplinary approach to the management of nosocomial pneumonia in adults. By integrating novel diagnostic modalities and refined therapeutic strategies, it aims to standardize care, improve patient outcomes, and enhance antimicrobial stewardship to curb the emergence of resistant pathogens.

Logistic Stewardship: Supporting Antimicrobial Stewardship Programs Based on Antibiotics Goods Flow

BACKGROUND/OBJECTIVES

Antimicrobial resistance is a global threat to safe health care, and a reduction in antibiotic consumption seems to be an appropriate preventive measure. In Germany, the reporting of hospital antibiotics consumption to an independent institution is only voluntary. Although a high level of willingness to improve can be assumed in the case of participation, the median consumptions of reporting hospitals change only slightly. This study examines the question of whether the logistical consumption figures adequately reflect real consumption, and if not, how to optimize the use of logistical data for clinical decisions.

METHODS

Four selected wards were analyzed during six months. A retrospective analysis of patient case files was performed to receive "prescribed daily doses" (PDDs). These were compared to "defined daily doses" (DDDs) from logistical data. Additional inventories were performed to calculated stored antibiotics. Antibiotics goods flows were presented via waterfall diagrams to identify logistic patterns that could explain PDD/DDD quotients. Antimicrobial stewardship (AMS) quality indicators were analyzed to give advice for optimized clinical AMS measures.

RESULTS

The total PDD/DDD quotient was 0.69. Four logistical patterns were identified. Optimized prophylaxis, AMS consultations and reevaluation of therapy seem to be the most useful measures to reduce PDDs.

CONCLUSIONS

If AMS programs rely solely on DDDs, measures cannot be optimal. A complete consideration of antibiotic goods flows supports clinical decisions, but is very costly in terms of data collection. The consideration of logistical data can help to identify areas of focus for AMS programs. Therefore, specialists of antibiotics logistics should complement clinical AMS teams.

Microdialysis sampling to monitor target-site vancomycin concentrations in septic infants: a feasible way to close the knowledge gap

This work is dedicated to the memory of Hartmut Derendorf (1953-2020), a pioneer of modern pharmacokinetics and valued mentor of this project.

OBJECTIVES

Septic infants/neonates need effective antibiotic exposure, but dosing recommendations are challenging as the pharmacokinetics in this age are highly variable. For vancomycin, which is used as a standard treatment, comprehensive pharmacokinetic knowledge especially at the infection site is lacking. Hence, an exploratory clinical study was conducted to assess the feasibility and safety of microdialysis sampling for vancomycin monitoring at the target site.

METHODS

Nine infants/neonates with therapeutic indications for vancomycin treatment were administered 15 mg/kg as 1-hour infusions every 8-24 hours. Microdialysis catheters were implanted in the subcutaneous interstitial space fluid of the lateral thigh. Samples were collected every 30 minutes over 24 hours, followed by retrodialysis for catheter calibration. Prior in vitro investigations have evaluated impact factors on relative recovery and retrodialysis.

RESULTS

In vitro investigations showed the applicability of microdialysis for vancomycin monitoring. Microdialysis sampling was well tolerated in all infants/neonates (23-255 days) without major bleeding or other adverse events. Pharmacokinetic profiles were obtained and showed plausible vancomycin concentration-time courses.

CONCLUSIONS

Microdialysis as a minimally invasive technique for continuous longer-term sampling is feasible and safe in infants/neonates. Interstitial space fluid profiles were plausible and showed substantial interpatient variation. Hence, a larger microdialysis trial is warranted to further characterise the pharmacokinetics and variability of vancomycin at the target site and ultimately improve vancomycin dosing in these vulnerable patients.