Therapy of ventilator-associated pneumonia. A patient-based approach based on the ten rules of "The Tarragona Strategy"

Serum concentration of continuously administered vancomycin influences efficacy and safety in critically ill adults: a systematic review

OBJECTIVES

Vancomycin is used to treat Gram-positive infections in critically ill adults. For vancomycin administered by continuous infusion (CI), various target ranges have been used, ranging from 15-20 mg/L to 30-40 mg/L. This systematic literature review was conducted to investigate the impact of steady-state serum concentration (Css) of CI on safety and efficacy of therapy in critically ill adults.

METHODS

Relevant literature was identified by searching two electronic databases (PubMed, Cochrane Library) and Google Scholar from inception until July 2023, focusing on studies reporting measured Css and treatment outcomes (e.g. mortality, nephrotoxicity) with CI. Due to study heterogeneity, a narrative synthesis of the evidence was performed.

RESULTS

Twenty-one publications were included with a total of 2949 patients. Mortality was higher (two studies, n = 388 patients) and clinical cure was lower (one study, n = 40 patients) with Css < 15 mg/L measured 24 h after initiation of CI (C24). An adequate loading dose appeared most important for maintaining higher C24. Generally, higher Css was associated with higher rates of acute kidney injury (AKI) (15 studies, n = 2331 patients). It was calculated that Css < 25 mg/L (versus ≥25 mg/L) was preferable for reducing nephrotoxicity (three studies, n = 515 patients).

CONCLUSIONS

Despite sparse data availability, the target range of 15-25 mg/L in CI may increase clinical cure and reduce mortality and AKI. In future research, vancomycin Css cohorts should be formed to allow evaluation of the impact of Css of CI on treatment outcomes.

„Die Puppe hat Luftnot“ – Simulation zum interprofessionellen Lernen im Team: aber sinnvoll!

Ausbildungskonzepte, die eine Simulation von Fällen und Szenarien aller Art nutzen, haben breiten Eingang in Curricula und Praxis gefunden. Ein Vertrauen in technische Simulationsmethoden ohne qualifizierte Ausbildung in der Methode kann schaden. Deswegen sollte nach der Auswahl der korrekten Simulationsmethode großer Wert auf die Durchführung der Simulation gelegt werden. Neben einem strukturierten Design der simulierten Szenarien und der korrekten technischen Durchführung ist für den Lernerfolg vor allem das Debriefing, die Nachbesprechung, entscheidend. Prüfungen mit Simulation als Methode sind nur zu empfehlen, wenn sie von Trainings getrennt durchgeführt werden und die Bewertung nach transparenten, validierten Kriterien erfolgt.

Implementation of Antibiotic Stewardship Improves the Quality of Blood Culture Diagnostics at an Intensive Care Unit of a University Hospital

Background: Bloodstream infections increase morbidity and mortality in hospitalized patients and pose a significant burden for health care systems worldwide. Optimal blood culture diagnostics are essential for early detection and specific treatment. After assessing the quality parameters at a surgical intensive care unit for six months, we implemented a diagnostic stewardship bundle (DSB) to optimize blood culture diagnostics and then reevaluated its effects after six months. Material and Methods: All patients ≥18 years old and on the ward were included: pre-DSB 137 and post-DSB 158. The standard quality parameters were defined as the number of blood culture sets per diagnostic episode (≥2), the rate of contamination (2–3%), the rate of positivity (5–15%), the collection site (≥1 venipuncture per episode) and the filling volume of the bottles (8–10 mL, only post-DSB). The DSB included an informational video, a standard operating procedure, and ready-to-use paper crates with three culture sets. Results: From pre- to post-interventional, the number of ≥2 culture sets per episode increased from 63.9% (257/402) to 81.3% (230/283), and venipunctures increased from 42.5% (171/402) to 77.4% (219/283). The positivity rate decreased from 15.1% (108/714) to 12.8% (83/650), as did the contamination rate (3.8% to 3.6%). The majority of the aerobic bottles were filled within the target range (255/471, 54.1%), but in 96.6%, the anaerobic bottles were overfilled (451/467). Conclusions: The implementation of DSB improved the quality parameters at the unit, thus optimizing the blood culture diagnostics. Further measures seem necessary to decrease the contamination rate and optimize bottle filling significantly.

Increased risk of ventilator-associated pneumonia in patients after cardiac arrest treated with mild therapeutic hypothermia

Background

We aimed at investigating the incidence, characteristics and outcome of ventilator‐associated pneumonia (VAP) in patients after cardiac arrest (CA) and its potential association with mild therapeutic hypothermia (MTH). We hypothesized, that MTH might increase the risk of VAP.

Methods

Prospective observational study including comatose adult patients after successful resuscitation from out‐of‐hospital or in‐hospital CA with presumed cardiac cause admitted to ICU and treated with MTH at 33°C for 24 h or normothermia (NT) with treatment of fever ≥38°C by pharmacological means. The primary outcome measure was the development of VAP. VAP diagnosis included mechanical ventilation >48 h combined with clinical and radiologic criteria. For a microbiologically confirmed VAP (mcVAP), a positive respiratory culture was required.

Results

About 23% of 171 patients developed VAP, 6% presented with mcVAP. VAP was associated with increased ICU‐LOS (9 (IQR 5–14) vs. 6 (IQR 3–9) days; p < .01), ventilator‐dependent days (6 (IQR 4–9) vs. 4 (IQR 2–7) days; p < .01) and duration of antibiotic treatment (9 (IQR 5–13) vs. 5 (IQR 2–9) days; p < .01), but not with mortality (OR 0.88 (95% CI: 0.43–1.81); p = .74). Patients treated with MTH (47%) presented higher VAP (30% vs. 17%; p = .04) and mcVAP rates (11% vs. 2%; p = .03). MTH was associated with VAP in multivariable logistic regression analysis with an OR of 2.67 (95% CI: 1.22–5.86); p = .01.

Conclusions

VAP appears to be a common complication in patients after CA, accompanied by more ventilator‐dependent days, prolonged antibiotic treatment, and ICU‐LOS. Treatment with MTH is significantly associated with development of VAP.

Biomarkers Predicting Tissue Pharmacokinetics of Antimicrobials in Sepsis: A Review

The pathophysiology of sepsis alters drug pharmacokinetics, resulting in inadequate drug exposure and target-site concentration. Suboptimal exposure leads to treatment failure and the development of antimicrobial resistance. Therefore, we seek to optimize antimicrobial therapy in sepsis by selecting the right drug and the correct dosage. A prerequisite for achieving this goal is characterization and understanding of the mechanisms of pharmacokinetic alterations. However, most infections take place not in blood but in different body compartments. Since tissue pharmacokinetic assessment is not feasible in daily practice, we need to tailor antibiotic treatment according to the specific patient’s pathophysiological processes. The complex pathophysiology of sepsis and the ineffectiveness of current targeted therapies suggest that treatments guided by biomarkers predicting target-site concentration could provide a new therapeutic strategy. Inflammation, endothelial and coagulation activation markers, and blood flow parameters might be indicators of impaired tissue distribution. Moreover, hepatic and renal dysfunction biomarkers can predict not only drug metabolism and clearance but also drug distribution. Identification of the right biomarkers can direct drug dosing and provide timely feedback on its effectiveness. Therefore, this might decrease antibiotic resistance and the mortality of critically ill patients. This article fills the literature gap by characterizing patient biomarkers that might be used to predict unbound plasma-to-tissue drug distribution in critically ill patients. Although all biomarkers must be clinically evaluated with the ultimate goal of combining them in a clinically feasible scoring system, we support the concept that the appropriate biomarkers could be used to direct targeted antibiotic dosing.

Development and validation of a simple and robust model to predict 30-day mortality in patients with Clostridioides difficile-associated enterocolitis

Objective

Clostridioides difficile infection (CDI) is a common healthcare-associated infection and associated with high morbidity and mortality. As current guidelines recommend treatment stratified for disease severity, this study aimed to identify predictors of 30-day mortality in order to develop a robust prediction model.

Design

This was a retrospective analysis of 207 inpatients with CDI who were treated at the Jena University Hospital between September 2011 and December 2015. In a training cohort (n=127), predictors of 30-day mortality were identified by receiver operating characteristics analysis and logistic regression. The derived model was validated in an independent cohort of 80 inpatients with CDI.

Results

Within 30 days, 35 (28%) patients in the training cohort died from any cause. C-reactive protein (CRP) of ≥121 mg/L (OR 3.80; 95% CI 1.64 to 7.80; p=0.003) and lower systolic blood pressure of ≤104 mm Hg (OR 3.73; 95% CI 1.63 to 8.53; p=0.002) at diagnosis as well as development of renal impairment (serum creatinine >1.5×baseline; OR 5.61; 95% CI 1.94 to 16.26; p=0.035) within the first 6 days were associated with 30-day mortality in univariate analysis. The use of these parameters enabled correct mortality prediction in 73% of cases on the day of diagnosis and in 76% at day 6. In the validation cohort, 30-day mortality was 18/80 (23%). Our model enabled a 73.7% correct prediction concerning 30-day mortality on day 6 after diagnosis of CDI.

Conclusion

Hypotension and CRP elevation on the day of diagnosis as well as occurrence of kidney dysfunction during the first 6 days are suitable parameters to predict 30-day mortality in patients with CDI who need to be treated in the hospital.

Adsorption therapy in critically ill with septic shock and acute kidney injury: a retrospective and prospective cohort study

Background

Haemoadsorption has been described as an effective way to control increased pro- and anti-inflammatory mediators (“cytokine storm”) in septic shock patients. No prospective or randomised clinical study has yet confirmed these results. However, no study has yet prospectively specifically investigated patients in severe septic shock with sepsis-associated acute kidney injury (SA-AKI). Therefore, we aimed to examine whether haemoadsorption could influence intensive care unit (ICU) and hospital mortality in these patients. Furthermore, we examined the influence of haemoadsorption on length of stay in the ICU and therapeutic support.

Methods

Retrospective control group and prospective intervention group design in a tertiary hospital in central Europe (Germany). Intervention was the implementation of haemoadsorption for patients in septic shock with SA-AKI. 76 patients were included in this analysis.

Results

Severity of illness as depicted by APACHE II was higher in patients treated with haemoadsorption. Risk-adjusted ICU mortality rates (O/E ratios) did not differ significantly between the groups (0.80 vs. 0.83). We observed in patients treated with haemoadsorption a shorter LOS and shorter therapeutic support such as catecholamine dependency and duration of RRT. However, in multivariate analysis (logistic regression for mortality, competing risk for LOS), we found no significant differences between the two groups.

Conclusions

The implementation of haemoadsorption for patients in septic shock with acute renal failure did not lead to a reduction in ICU or hospital mortality rates. Despite univariate analysis delivering some evidence for a shorter duration of ICU-related treatments in the haemoadsorption group, these results did not remain significant in multivariate analysis.

Trial registration CytoSorb^® registry https://clinicaltrials.gov/ct2/show/NCT02312024. December 9, 2014. Database: https://www.cytosorb-registry.org/ (registration for content acquisition is necessary)

Incisional negative pressure wound therapy does not reduce surgical site infections in abdominal midline incisions: a case control study

Purpose: There is evidence from various surgical specialties that incisional negative pressure wound therapy (iNPWT) might reduce postoperative surgical site infections (SSIs). In visceral and general surgery, there is varying evidence of its efficacy in reducing surgical site infections.Methods: A prospectively registered patient cohort of 43 patients with abdominal wall and visceral surgery received treatment with iNPWT and was compared to a matched retrospective cohort to analyze its effects on SSI occurrence and respective risk factors. Groups were matched by procedure, sex, body mass index and age. We used two different systems of iNPWT: (i) PREVENA^TM or (ii) self-made epicutaneous iNPWT from common VAC material.Results: We could not find a total reduction in postoperative SSIs by application of iNPWT. But within the iNPWT cohort, patients with self-made iNPWT suffered more often from SSIs compared to the commercial iNPWT subgroup. No patient specific risk factors could be identified to advocate the use of iNPWT.Conclusion: Our data do not support the use of an incisional negative pressure wound therapy on closed wounds in midline laparotomy incisions. Although, differences exist between the commmercial and self-made systems.

Bacterial sepsis : Diagnostics and calculated antibiotic therapy

The mortality of patients with sepsis and septic shock is still unacceptably high. An effective calculated antibiotic treatment within 1 h of recognition of sepsis is an important target of sepsis treatment. Delays lead to an increase in mortality; therefore, structured treatment concepts form a rational foundation, taking relevant diagnostic and treatment steps into consideration. In addition to the assumed infection and individual risks of each patient, local resistance patterns and specific problem pathogens must be taken into account during the selection of anti-infective treatment. Many pathophysiologic alterations influence the pharmacokinetics (PK) of antibiotics during sepsis. The principle of standard dosing should be abandoned and replaced by an individual treatment approach with stronger weighting of the pharmacokinetics/pharmacodynamics (PK/PD) index of the substance groups. Although this is not yet the clinical standard, prolonged (or continuous) infusion of β‑lactam antibiotics and therapeutic drug monitoring (TDM) can help to achieve defined PK targets. Prolonged infusion is sufficient without TDM, but for continuous infusion, TDM is generally necessary. A further argument for individual PK/PD-oriented antibiotic approaches is the increasing number of infections due to multidrug-resistant (MDR) pathogens in the intensive care unit. For effective treatment, antibiotic stewardship teams (ABS teams) are becoming more established. Interdisciplinary cooperation of the ABS team with infectious disease (ID) specialists, microbiologists, and clinical pharmacists leads not only to rational administration of antibiotics, but also has a positive influence on treatment outcome. The gold standards for pathogen identification are still culture-based detection and microbiologic resistance testing for the various antibiotic groups. Despite the rapid investigation time, novel polymerase chain reaction(PCR)-based procedures for pathogen identification and resistance determination are currently only an adjunct to routine sepsis diagnostics, due to the limited number of studies, high costs, and limited availability. In complicated septic courses with multiple anti-infective therapies or recurrent sepsis, PCR-based procedures can be used in addition to treatment monitoring and diagnostics. Novel antibiotics represent potent alternatives in the treatment of MDR infections. Due to the often defined spectrum of pathogens and the practically (still) absent resistance, they are suitable for targeted treatment of severe MDR infections (therapy escalation). (Contribution available free of charge by "Free Access" [ https://link.springer.com/article/10.1007/s00101-017-0396-z ].).

[Antibiotic stewardship (ABS). Part 2: Application]

Antibiotic stewardship (ABS) is an important measure to counteract the spread of resistant pathogens and multidrug resistance. The most important ABS tools include the implementation of local guidelines, the development of a house-related list of anti-infective agents, regular ABS visits and practice-oriented internal training events. Effective strategies for therapy optimization include indication testing and therapy evaluation, dose optimization as well as determining an appropriate duration of therapy. Oralization of anti-infectives (sequence therapy) should be supported by consistent clinical criteria in in-house guidelines. The incidence of Clostridioides difficile infections (CDI) can be more than halved by restricting the so-called "4C antibiotics". Point-of-care tests help to minimize the use of antibiotics in the outpatient setting. Vaccination reduces the need for antibiotic therapy.

Development of the Bacterial Spectrum and Antimicrobial Resistance in Surgical Site Infections of Trauma Patients

Background: While ubiquitously multi-resistant bacteria are on the rise, peri-operative antimicrobial prophylaxis in trauma and near-to-bone surgical procedures has only been changed slightly during the last 25 years. Recent clinical studies concerning the bacterial spectrum and efficacy of antimicrobial treatment in infected trauma surgical patients are rare. The aim of the study was analysis of the contemporary bacterial spectrum and its antimicrobial resistance including the assessment of the appropriateness of peri-operative antimicrobial prophylaxis with cefuroxime. Methods: Patients of a level-I academic trauma center who underwent open or arthroscopic surgery because of a recent trauma necessitating the use of bone-near metal implants were included in the study. All patients in whom a surgical site infection (SSI) had developed during six weeks post-operatively necessitating surgical debridement and had positive microbiologic culture results from an intra-operative surgical site swab were analyzed, retrospectively. In particular, age, gender, date and duration of surgical interventions, and patient's related risk factors were collected, and infecting agents and their minimum inhibitory concentration values for 34 selected antimicrobial agents were evaluated. An SSI occurring later than 6 weeks post-operatively and patients with chronic and septic wounds were excluded. Statistical analysis was performed with SPSS^® (IBM, Armonk, NY). Results: There were 438 pathogens cultured in specimens from 303 enrolled patients (female = 140, male = 163). The most frequent pathogens were Staphylococcus aureus (27.1%), S. epidermidis (20.6%), Enterococcus faecalis (13.6%), Escherichia coli (5.1%), and Pseudomonas aeruginosa (3.7%) accounting for 303 isolates. Of those, 89 (29.4%) were multi-resistant. Of the S. epidermidis isolates, 79.8% (n = 71) were resistant against Oxacillin and thus against most beta-lactam antibiotic agents. Altogether, only 44.1% of the infecting organisms were susceptible to cefuroxime, the antimicrobial agent most often being used for prophylactic purposes. Conclusion: Standardized antimicrobial prophylaxis with cephalosporins has to be reconsidered critically. Multi-resistant species such as S. epidermidis are an increasing challenge in trauma operations.

[Necrotizing fasciitis]

Necrotizing fasciitis is a rare but always life-threatening disease, which necessitates a rapid diagnosis and immediate treatment. It can occur on the extremities as well as on the trunk and the perineum. It spreads rapidly along the fascia leading to septic shock. The mortality rate under intensive care treatment is approximately 20%. The pathogen spectrum ranges from mixed bacterial infections to group A streptococci, clostridia and fungi. Clinically, the discrepancy between skin affection and systemic disease symptoms is remarkable. The diagnosis is primarily clinical and the key to successful treatment is rapid and radical surgical debridement combined with broad-spectrum antibiotic therapy under intensive patient monitoring.

Gastrointestinal colonization with multidrug-resistant Gram-negative bacteria during extracorporeal membrane oxygenation: effect on the risk of subsequent infections and impact on patient outcome

Background

In ICU patients, digestive tract colonization by multidrug-resistant (MDR) Gram-negative (G−) bacteria is a significant risk factor for the development of infections. In patients undergoing extracorporeal membrane oxygenation (ECMO), colonization by MDR bacteria and risk of subsequent nosocomial infections (NIs) have not been studied yet. The aim of this study is to evaluate the incidence, etiology, risk factors, impact on outcome of gastrointestinal colonization by MDR G− bacteria, and risk of subsequent infections in patients undergoing ECMO.

Methods

This is a retrospective analysis of prospectively collected data: 105 consecutive patients, treated with ECMO, were admitted to the ICU of an Italian tertiary referral center (San Gerardo Hospital, Monza, Italy) from January 2010 to November 2015. Rectal swabs for MDR G− bacteria were cultured at admission and twice a week. Only colonization and NIs by MDR G− bacteria were analyzed.

Results

Ninety-one included patients [48.5 (37–56) years old, 63% male, simplified acute physiology score II 37 (32–47)] underwent peripheral ECMO (87% veno-venous) for medical indications (79% ARDS). Nineteen (21%) patients were colonized by MDR G− bacteria. Male gender (OR 4.03, p = 0.029) and duration of mechanical ventilation (MV) before ECMO > 3 days (OR 3.57, p = 0.014) were associated with increased risk of colonization. Colonized patients had increased odds of infections by the colonizing germs (84% vs. 29%, p < 0.001, OR 12.9), longer ICU length of stay (LOS) (43 vs. 24 days, p = 0.002), MV (50 vs. 22 days, p < 0.001) and ECMO (28 vs. 12 days, p < 0.001), but did not have higher risk of death (survival rate 58% vs. 67%, p = 0.480, OR 0.68). Infected patients had almost halved ICU survival (46% vs. 78%, p < 0.001, OR 4.11).

Conclusions

In patients undergoing ECMO for respiratory and/or circulatory failure, colonization by MDR G− bacteria is frequent and associated with more the tenfold odds for subsequent infection. Those infections are associated with an increased risk of death.

[Antibiotic stewardship : Measures for optimizing prescription of anti-infective agents]

Antibiotic stewardship (ABS) comprises a bundle of different interventions to improve anti-infective treatment in a hospital setting. An important component of ABS interventions is the interdisciplinary approach to infection management. Besides improving infrastructural aspects on a hospital level, including surveillance of the use of anti-infective agents and nosocomial infections, collation and interpretation of statistics on resistance and formulation of local treatment guidelines, ABS teams go to the wards and advise treating physicians on antibiotic therapy. Frequent approaches for optimization are selection of substances, administration route, dosing of medication and duration of treatment. An important overall objective of ABS is the reduction of resistance induction in order to preserve the therapeutic efficiency of antibiotics. A number of studies have shown that this goal can be achieved in different clinical settings without negatively affecting patient outcome. The strategies of ABS can also be applied with no problems to critically ill patients on the intensive care unit.

[Bacterial sepsis : Diagnostics and calculated antibiotic therapy]

The mortality of patients with sepsis and septic shock is still unacceptably high. An effective antibiotic treatment within 1 h of recognition of sepsis is an important target of sepsis treatment. Delays lead to an increase in mortality; therefore, structured treatment concepts form a rational foundation, taking relevant diagnostic and treatment steps into consideration. In addition to the assumed focus and individual risks of each patient, local resistance patterns and specific problem pathogens must be taken into account for selection of anti-infection treatment. Many pathophysiological alterations influence the pharmacokinetics of antibiotics during sepsis. The principle of standard dosing should be abandoned and replaced by an individual treatment approach with stronger weighting of the pharmacokinetics/pharmacodynamics (PK/PD) index of the substance groups. Although this is not yet the clinical standard, prolonged (or continuous) infusion of beta-lactam antibiotics and therapeutic drug monitoring (TDM) can help to achieve defined PK targets. Prolonged infusion is sufficient without TDM but for continuous infusion TDM is basically necessary. A further argument for individual PK/PD-oriented antibiotic approaches is the increasing number of infections due to multidrug resistant pathogens (MDR) in the intensive care unit. For effective treatment antibiotic stewardship teams (ABS team) are becoming more established. Interdisciplinary cooperation of the ABS team with infectiologists, microbiologists and clinical pharmacists leads not only to a rational administration of antibiotics but also has a positive influence on the outcome. The gold standards for pathogen detection are still culture-based detection and microbiological resistance testing for the various antibiotic groups. Despite the rapid investigation time, novel polymerase chain reaction (PCR)-based procedures for pathogen identification and resistance determination, are currently only an adjunct to routine sepsis diagnostics due to the limited number of studies, high costs and limited availability. In complicated septic courses with multiple anti-infective treatment or recurrent sepsis, PCR-based procedures can be used in addition to therapy monitoring and diagnostics. Novel antibiotics represent potent alternatives in the treatment of MDR infections. Due to the often defined spectrum of pathogens and the practically absent resistance, they are suitable for targeted treatment of severe MDR infections (therapy escalation).

Quality indicators in intensive care medicine for Germany - third edition 2017

Quality improvement in medicine is depending on measurement of relevant quality indicators. The quality indicators for intensive care medicine of the German Interdisciplinary Society of Intensive Care Medicine (DIVI) from the year 2013 underwent a scheduled evaluation after three years. There were major changes in several indicators but also some indicators were changed only minimally. The focus on treatment processes like ward rounds, management of analgesia and sedation, mechanical ventilation and weaning, as well as the number of 10 indicators were not changed. Most topics remained except for early mobilization which was introduced instead of hypothermia following resuscitation. Infection prevention was added as an outcome indicator. These quality indicators are used in the peer review in intensive care, a method endorsed by the DIVI. A validity period of three years is planned for the quality indicators.

Reconsidering Current Decorporation Strategies after Incorporation of Radionuclides

In the case of a nuclear accident or a terrorist attack by a "dirty bomb," there is a risk of external and internal contamination with radionuclides in addition to external irradiation. Internal irradiation as a consequence of radionuclide incorporation is associated with a higher risk of stochastic radiation effects (e.g., tumors). Decorporation treatment will enhance the elimination of radionuclides and reduce the committed effective dose as a metric of stochastic health effects. Although treatment efficacy is better when started early, beginning the therapy without knowing the committed effective dose may unnecessarily expose the patient to the side effects of the medication. The question is: Delay the therapy to wait for the results of internal dosimetry or start the therapy promptly on spec? To prove insight into this question, a selective review of the literature was conducted. The importance of the initiation time of treatment in the efficacy of decorporation treatment can be explained with pharmacokinetic laws and first order processes determining the disposition of xenobiotics in the organism. Nevertheless, there is no internationally accepted standard on when to start a decorporation therapy (exception: iodide). The "precautionary approach," emphasizing the importance of the committed effective dose for the indication of treatment, is competing with the "urgent approach" advocating the administration of medication "a priori" within several hours. A review of the literature actually indicates that the most important drugs used for decorporation are well tolerated with few adverse effects. In consideration of the higher efficacy and the low side-effects of a short-term treatment, initiating decorporation therapy as soon as possible after internal contamination, even before the committed effective dose has been assessed, appears to be a reasonable approach. The decision of continuation or discontinuation of the therapy should be taken after internal dosimetry is completed on the basis of the committed effective dose.

Ventilator-Associated Pneumonia: A Review

Ventilator-associated pneumonia is the most frequent intensive care unit (ICU)-related infection in patients requiring mechanical ventilation. In contrast to other ICU-related infections, which have a low mortality rate, the mortality rate for ventilator-associated pneumonia ranges from 20% to 50%. These clinically significant infections prolong duration of mechanical ventilation and ICU length of stay, underscoring the financial burden these infections impose on the health care system. The causes of ventilator-associated pneumonia are varied and differ across different patient populations and different types of ICUs. This varied presentation underscores the need for the intensivist treating the patient with ventilator-associated pneumonia to have a clear knowledge of the ambient microbiologic flora in their ICU. Prevention of this disease process is of paramount importance and requires a multifaceted approach. Once a diagnosis of ventilator-associated pneumonia is suspected, early broad-spectrum antibiotic administration decreases morbidity and mortality and should be based on knowledge of the sensitivities of common infecting organisms in the ICU. De-escalation of therapy, once final culture results are available, is necessary to minimize development of resistant pathogens. Duration of therapy should be based on the patient’s clinical response, and every effort should be made to minimize duration of therapy, thus further minimizing the risk of resistance.

Why a second look might be worth it: immuno-modulatory therapies in the critically ill patient

Sepsis and septic shock are associated with high mortality rates and remain a serious menace for the critically ill patient. Concurrent activation of pro- and anti-inflammatory pathways and an excessive cytokine release represent initial key features in the deregulation of the humoral and cellular antimicrobial defense. Research of the last decades addressed both the ebullient inflammation as well as the resulting long-term failure of the host immunity. While the reestablishment of an adequate immune-competence is still under investigation, many promising experimental trials to limit the inflammatory response during sepsis were challenged by missing beneficial effects in clinical studies. Nevertheless, due to advanced knowledge about the complex regulation of inflammatory mediators and their overlapping involvement in other potentially life-threatening diseases, further evaluation of these approaches in relevant subgroups could help to identify critically ill patients with potential benefit from anti-inflammatory therapies.

Pseudomonas aeruginosa ventilator-associated pneumonia management

Ventilator-associated pneumonia is the most common infection in intensive care unit patients associated with high morbidity rates and elevated economic costs; Pseudomonas aeruginosa is one of the most frequent bacteria linked with this entity, with a high attributable mortality despite adequate treatment that is increased in the presence of multiresistant strains, a situation that is becoming more common in intensive care units. In this manuscript, we review the current management of ventilator-associated pneumonia due to P. aeruginosa, the most recent antipseudomonal agents, and new adjunctive therapies that are shifting the way we treat these infections. We support early initiation of broad-spectrum antipseudomonal antibiotics in present, followed by culture-guided monotherapy de-escalation when susceptibilities are available. Future management should be directed at blocking virulence; the role of alternative strategies such as new antibiotics, nebulized treatments, and vaccines is promising.

Cardiovascular causes of emergency neurology presenting to an ICU

Stroke or transient ischemic attacks (TIA) represent an urgent clinical entity that is not limited only to elderly patients. The underlying causes of stroke and TIA are diverse, with those of cardiovascular origin being among the most prominent. This review seeks to elucidate some of the most important aspects of the disease in the context of emergency and critical care practice.

[Epigenetic regulation in sepsis : current state of knowledge]

Sepsis is known to be a severe systemic immune reaction based on an infection of various origins. The initial immune response is accompanied by excess activation of immune cells and release of proinflammatory cytokines. Simultaneously initiated compensatory mechanisms lead to high levels of anti-inflammatory mediators to counterbalance the generalized inflammatory reaction; however, the compensatory immunoreaction itself equally overreacts and results in a prolonged sepsis-induced immunosuppression. The underlying mechanisms for these exaggerated immune responses and the resulting global immunosuppression that increase the risk for secondary infection are still unknown. Recent findings indicate that epigenetic mechanisms change basic properties of important immune cells by mechanisms leading to changes in gene expression. Dynamic exchanges of histone modifications result in a variation of transcription and seem to play a key role in cell function of macrophages and other immune cells. This article provides a current overview of epigenetic sepsis research and the sepsis-induced effects on the immune system.

Variability of linezolid concentrations after standard dosing in critically ill patients: a prospective observational study

Introduction

Severe infections in intensive care patients show high morbidity and mortality rates. Linezolid is an antimicrobial drug frequently used in critically ill patients. Recent data indicates that there might be high variability of linezolid serum concentrations in intensive care patients receiving standard doses. This study was aimed to evaluate whether standard dosing of linezolid leads to therapeutic serum concentrations in critically ill patients.

Methods

In this prospective observational study, 30 critically ill adult patients with suspected infections received standard dosing of 600 mg linezolid intravenously twice a day. Over 4 days, multiple serum samples were obtained from each patient, in order to determine the linezolid concentrations by liquid chromatography tandem mass spectrometry.

Results

A high variability of serum linezolid concentrations was observed (range of area under the linezolid concentration time curve over 24 hours (AUC₂₄) 50.1 to 453.9 mg/L, median 143.3 mg*h/L; range of trough concentrations (C_min) < 0.13 to 14.49 mg/L, median 2.06 mg/L). Furthermore, potentially subtherapeutic linezolid concentrations over 24 hours and at single time points (defined according to the literature as AUC₂₄ < 200 mg*h/L and C_min < 2 mg/L) were observed for 63% and 50% of the patients, respectively. Finally, potentially toxic levels (defined as AUC₂₄ > 400 mg*h/L and C_min > 10 mg/L) were observed for 7 of the patients.

Conclusions

A high variability of linezolid serum concentrations with a substantial percentage of potentially subtherapeutic levels was observed in intensive care patients. The findings suggest that therapeutic drug monitoring of linezolid might be helpful for adequate dosing of linezolid in critically ill patients.

Trial registration

Clinicaltrials.gov NCT01793012. Registered 24 January 2013.

[Tarragona strategy--appropriate antibiotic therapy in the ICU]

BACKGROUND

Appropriate antibiotic initial therapy remarkably decreases the mortality of patients with infections in the ICU. The establishment of an appropriate initial therapy follows empirical aspects. This practice was first done for the treatment of nosocomial pneumonia. Since that time the practice became known as Tarragona strategy.

RESULTS

The basic elements of the strategy are based on the initial antibiotic treatment of patients with infections in the ICU in general and include the following: view the patient and his/her medical history, consider the microbiologic environment, in which the patient became ill, test for possible causative microorganisms and initiate high-dose antibiotics immediately, evaluate pharmacokinetic/pharmacodynamic aspects influenced by the pathophysiologic processes in the critically ill patient, the specifics of the microorganisms, the peculiarity of the antibiotics in the patient and due to therapeutic procedures, and tailor the initial broad spectrum therapy as necessary according to the microbiological results.

CONCLUSION

This procedure is safe, reduces mortality, limits the development of resistance, and is economic.

Risk factors and outcome of bacterial infections in cirrhosis

Viable and non-viable pathological bacterial translocation promote a self-perpetuating circle of dysfunctional immune activation and systemic inflammation facilitating infections and organ failure in advanced cirrhosis. Bacterial infections and sepsis are now recognized as a distinct stage in the natural progression of chronic liver disease as they accelerate organ failure and contribute to the high mortality observed in decompensated cirrhosis. The increasing knowledge of structural, immunological and hemodynamic pathophysiology in advanced cirrhosis has not yet translated into significantly improved outcomes of bacterial infections over the last decades. Therefore, early identification of patients at the highest risk for developing infections and infection-related complications is required to tailor the currently available measures of surveillance, prophylaxis and therapy to the patients in need in order to improve the detrimental outcome of bacterial infections in cirrhosis.

Ventilator-Associated Pneumonia: When to hold the breath?

Ventilator-associated pneumonia (VAP) is the most common infection in mechanically ventilated patients, and carries the highest mortality. An early diagnosis and definitive management not only reduces the overall mortality, but also brings down the burden of health care to the patient by reducing the cost, length of Intensive Care Unit (ICU) stay, duration of mechanical ventilation, and so on. Out of the various scoring systems, the Clinical Pulmonary Infection Score (CPIS) calculation for VAP has a good sensitivity (72%) and specificity (85%) and the targeted antibiotic therapy in the appropriate dosage is found to be more beneficial than empirical treatment. Although controversies persist on several issues, preventive strategies like head elevation by 30 degrees, cuff pressure monitoring, avoidance of sedatives and muscle relaxants, and so on, have been found to reduce the occurrence of VAP.

Dose modulation: a new concept of antibiotic therapy in the critically ill patient?

Considerable evidence has shown that adequate antibiotic therapy is of utmost importance in the critically ill septic patient. However, antibiotic concentration may be insufficient early in infection course. We propose the concept of dose modulation, meaning front-line variability of antibiotic dose, according to patient and microorganism characteristics, followed by its reduction after clinical response and patient recovery. Therefore, dose modulation means concentrating the largest weight of antibiotics at the front-end, when the microbial load is higher and the pharmacokinetic changes poses the highest risk of underdosing and nibbling off antibiotic dose, when the sepsis syndrome is improving, guided by pharmacokinetic and pharmacodynamic data.

Mikrobiologie und Antiinfektiva

Bei einem 38-jährigen Patienten wurde eine Analfistel operiert. Am 3. postoperativen Tag kommt es zur akuten Verschlechterung des Gesundheitszustands mit hämodynamischer Instabilität und Fieber. Daraufhin wird der Patient in eine Klinik der Maximalversorgung verlegt. Beim Eintreffen im Schockraum ist der Patient somnolent und kaltschweißig. Der Blutdruck beträgt 70/40 mmHg, die Herzfrequenz 120/min und die Körpertemperatur 39,6°C. Das Hautkolorit ist blass-grau. Im Verlegungsbericht wird bei stark ödematös geschwollenem Skrotum der Verdacht auf eine Fournier-Gangrän nach Analfistel- OP gestellt. Der diensthabende Intensivmediziner muss nun parallel die hämodynamische Situation stabilisieren, mikrobiologisches Material gewinnen, eine kalkulierte antimikrobielle Therapie beginnen und weitere Maßnahmen zur Diagnosesicherung einleiten.

Evaluation of a polymerase chain reaction assay for pathogen detection in septic patients under routine condition: an observational study

Background

Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis.

Methodology/Principal Findings

This was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO®) were obtained. 45 of 311 blood cultures (14.5%) and 94 of 311 PCRs (30.1%) were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5) hours for the PCR and 68 (52.2, 88.5) hours for BC (p<0.01). PCR median time to result was dependent on technician availability (53.5 hours on Saturdays, 7.2 hours under optimal logistic conditions). PCR results showed good correlation with procalcitonin (p<0.001). In 34% of patients with positive PCRs antimicrobial therapy was considered inadequate according to assessment of clinical arbitrators including 5 patients with vancomycin-resistant enterococci (VRE), 3 cases with multiresistant staphylococci, and 4 patients with fungi.

Conclusions

The results of this observational study support the hypothesis that PCR results are available faster, are more frequently positive, and may result in earlier adjustment of antimicrobial therapy. However, shorter time to result can only be fully exploited when the laboratory is adequately staffed for a 24 hour/7 day service, or when point of care/automated assay systems become available.

Emergence of spontaneous bacterial peritonitis due to enterococci - risk factors and outcome in a 12-year retrospective study

BACKGROUND

Third-generation cephalosporins (TGC) constitute the empirical first-line therapy for spontaneous bacterial peritonitis (SBP). Hospitalisation, invasive procedures and use of antibiotics may challenge this concept due to an increase in enterococci and other TGC-resistant microorganisms.

AIM

To determine prevalence, risk factors and outcome of ascitic fluid infections caused by enterococci.

METHODS

All independent episodes of culture-positive ascitic fluid between 2000 and 2011 in a German tertiary centre were analysed retrospectively.

RESULTS

Out of 244 positive ascitic fluid cultures, 90 episodes of monomicrobial SBP and 25 episodes of monomicrobial bacterascites (BA) in patients with decompensated cirrhosis were identified. Enterococcus spp. were isolated in 32 (28%) episodes. We noticed a profound increase in the frequency of enterococcal infection over the study period from 11% to 35% (P = 0.007). Univariate risk factors for enterococcal SBP/BA included nosocomial infection (OR = 4.56; 95% CI 1.90-10.97), previous use of antibiotics (OR = 5.63; 95% CI 1.81-17.49) and recent gastrointestinal endoscopy (OR = 3.17; 95% CI 1.33-7.54). Nosocomial infection (OR = 3.29; P = 0.011) and recent antibiotic therapy (OR = 3.88; P = 0.025) remained independent risk factors for enterococcal infection in multivariate logistic regression and these factors contributed also to the model when only SBP cases were considered. In subjects with monomicrobial SBP who were treated with TGC or ciprofloxacin, the probability of 90-day survival was 12% in enterococcal infection compared to 50% in non-enterococcal SBP (P = 0.022 in log-rank test).

CONCLUSION

Because of the increasing prevalence of enterococcal spontaneous bacterial peritonitis and its poor prognosis when treated inappropriately, clinicians should consider empirical therapy with anti-enterococcal antibiotics for patients with risk factors.

PCR-based rapid sepsis diagnosis effectively guides clinical treatment in patients with new onset of SIRS

INTRODUCTION

Early detection of the causing microorganism and timely therapeutic intervention are crucial for improved outcome of patients with sepsis. Quite recently, we evaluated the technical and diagnostic feasibility of a commercial multiplex real-time polymerase chain reaction (PCR) (LightCycler SeptiFast® assay) for detection of blood stream infections in a cohort of intensive care unit (ICU) patients with the risk of abdominal sepsis.

RESULTS AND FINDINGS

The PCR positivity rate showed a high coincidence with systemic inflammatory response syndrome (SIRS; 75.8%). In this study, we focussed on patients from the same surgical ICU with upcoming SIRS and addressed the utility on therapeutic decision making following diagnostic application of PCR in addition and comparison to conventional microbiological and laboratory tests. In total, 104 patients on the ICU fulfilling the American College of Chest Physicians/Society of Critical Care Medicine SIRS criteria were enrolled. Blood samples were taken within 24 h of upcoming SIRS. Some 39.9% (n = 59) of the blood samples (n (Total) = 148) were positive using multiplex-PCR and 20.3% (n = 30) using conventional culture. In 11.4% of all samples, multiplex-PCR detected more than one microorganism. Among the 77 microorganisms identified by multiplex-PCR, only 25 (32.5%) could be confirmed by blood culture; an additional 17 could be confirmed by microbiological test results from other significant patient specimen. Positive blood samples independent of the detection method were characterised by significant elevated levels of procalcitonin (p < 0.05) but not C-reactive protein. In 25 cases (16.9%, n = 148), the rapid identification of involved pathogens by multiplex-PCR led to prompt adjustment of therapy.

CONCLUSIONS

Our study demonstrates improved detection of specific pathogens with a high intrinsic resistance and positive impact on therapeutic decision-making by additional multiplex-PCR-based analysis of blood samples for infectious agents in patients with new onset of SIRS. Thus, we showed for the first time that PCR test results guide clinical treatment successfully.

Appropriateness is critical

Inappropriate empirical antibiotic therapy for severe infections in the intensive care unit is a modifiable prognostic factor that has a great effect on patient outcome and health care resources. Inappropriate treatment is usually associated with microorganisms resistant to the common antibiotics, which must be empirically targeted when risk factors are present. Previous antibiotic exposure, prolonged length of hospital stay, admission category, local susceptibilities, colonization pressure, and the presence of invasive devices increase the likelihood of infection by resistant pathogens. Consideration of issues beyond in vitro susceptibility, such as antibiotic physicochemistry, tissue penetration, and pharmacokinetic/pharmacodynamic-driven dosing, is mandatory for the optimization of antibiotic use.

[Antibiotic treatment of nosocomial pneumonia]

Nosocomial pneumonia is one of the most common infectious diseases acquired in hospital and is often caused by resistant pathogens. For treatment of nosocomial pneumonia an appropriate initial antibiotic therapy is essential and exact knowledge of the specific pathogen spectrum is essential for the correct choice of the empirically calculated antibiotics. In line with a critical reevaluation of the primary treatment, pathogen-specific de-escalation therapy, a diagnosis of possible pulmonary complications (e. g. pleural empyema) and the identification and appropriate rehabilitation measures of non-pulmonary infections are necessary. To attain the best possible outcome the respective therapy concept needs to be adjusted to the individual risk characteristics. Appropriate initial antibiotic therapy, duration of mechanical ventilation and comorbidities are the key factors for patient outcome. This approach helps to avoid the development of resistant pathogens and saves economic resources.

Clinical pharmacodynamics and pharmacokinetics of the antifungal extended-spectrum triazole posaconazole: an overview

In recent years, the antifungal triazole posaconazole has become increasingly important for the prophylaxis and treatment of systemic mycoses. Although oral bioavailability of posaconazole can be enhanced by concomitant food intake and administration in divided daily doses, increased gastric pH or gut motility, as well as enzyme-inducing drugs, can result in lower plasma concentrations than expected. Whether therapeutic drug monitoring can reduce the risk of treatment failures by avoiding sub-therapeutic plasma concentrations needs further examination. Based on the ability of posaconazole to inhibit cytochrome P450 3A4, several drug interactions can be expected, especially with agents that undergo extensive first-pass effect through the gut and the liver. However, more information is needed regarding dose modifications during concomitant administration of posaconazole with drugs in certain categories, such as vinca alkaloids and retinoids, along with selected individual drugs such as everolimus.

Treatment of complicated intra-abdominal infections in the era of multi-drug resistant bacteria

The management of severe intra-abdominal infections remains a major challenge facing surgeons and intensive care physicians, because of its association with high morbidity and mortality. Surgical management and intensive care medicine have constantly improved, but in the recent years a rapidly continuing emergence of resistant pathogens led to treatment failure secondary to infections with multi-drug resistant bacteria. In secondary peritonitis the rate of resistant germs at the initial operation is already 30%. The lack of effective antibiotics against these pathogens resulted in the development of new broad-spectrum compounds and antibiotics directed against resistant germs. But so far no "super-drug" with efficacy against all resistant bacteria exists. Even more, soon after their approval, reports on resistance against these novel drugs have been reported, or the drugs were withdrawn from the market due to severe side effects. Since pharmaceutical companies reduced their investigations on antibiotic research, only few new antimicrobial derivates are available.

In abdominal surgery you may be in fear that in the future more and more patients with tertiary peritonitis secondary to multi-drug resistant species are seen with an increase of mortality after secondary peritonitis.

This article reviews the current treatment modalities for complicated intra-abdominal infections with special reference to the antibiotic treatment of complicated intra-abdominal infections with multi-drug resistant species.

Mikrobiologie und Antiinfektiva

Bei einem 38-jährigen Patienten wurde eine Analfistel operiert. Am 3. postoperativen Tag kommt es zur akuten Verschlechterung des Gesundheitszustands mit hämodynamischer Instabilität und Fieber. Daraufhin wird der Patient in eine Klinik der Maximalversorgung verlegt. Beim Eintreffen im Schockraum ist der Patient somnolent und kaltschweißig. Der Blutdruck beträgt 70/40 mmHg, die Herzfrequenz 120/min und die Körpertemperatur 39,6°C. Das Hautkolorit ist blass-grau. Im Verlegungsbericht wird bei stark ödematös geschwollenem Skrotum der Verdacht auf eine Fournier-Gangrän nach Analfistel-OP gestellt. Der diensthabende Intensivmediziner muss nun parallel die hämodynamische Situation stabilisieren, mikrobiologisches Material gewinnen, eine kalkulierte antimikrobielle Therapie beginnen und weitere Maßnahmen zur Diagnosesicherung einleiten.

[Questionnaire surveying nephrologists on drug dose adjustment in patients with impaired kidney function]

OBJECTIVE

Our intention was to assess knowledge and requirements related to drug dose adjustment in patients with impaired kidney function.

METHOD

In 2005, we sent a questionnaire containing 22 questions to nephrologists in Germany and Austria. With 77 responses, the study was not representative. However, it was probably of importance for the target group of practising physicians and potential users of a future drug information system.

RESULTS

Only 28% of the responding colleagues use the package inserts; these are obviously not considered to be an obligatory guideline for dose adjustment. The most common dosing problems (p < 0.05) were associated with anti-infective (48%) and anti-cancer drugs (25%). The greatest problems with dosing were encountered within intensive care units (29%). The risk of excessive dosing is estimated significantly more serious than the risk of underdosing (51% vs. 23%, p = 0.02). There was support for the statement that for cephalosporin antibiotics the trough levels are more important than peak levels (58% vs. 27%, p < 0.01). However, only 8% knew that in patients with impaired kidney function, trough concentrations of aminoglycosides and vancomycin need to be higher than in patients with normal kidney function for adequate peak levels to be obtained. Forty-five percent of respondents erroneously presumed that ceftriaxone must be adjusted to the kidney function. Half of the respondents were incorrect in assuming that ceftriaxone or moxifloxacin would be removed by dialysis.

CONCLUSIONS

We see the need for more knowledge-based information on drug dosing in patients with kidney impairment and those in the intensive care unit. The risk to life posed by underdosage might be underestimated, especially for anti-infective drugs.

Ventilator-associated pneumonia: epidemiology and impact on the clinical evolution of ICU patients

OBJECTIVE

Although ventilator-associated pneumonia (VAP) is a major cause of nosocomial infection, its role in the prognosis of patients remains undefined. The objective of this study was to evaluate the impact of VAP on the clinical evolution of patients.

METHODS

This was a prospective cohort study involving 233 patients on mechanical ventilation (VAP group, n = 64; control group, n = 169). Primary outcomes were time on mechanical ventilation (TMV), time in ICU (TICU), overall length of hospital stay (LHS) and in-ICU mortality. Secondary outcomes were in-hospital mortality, microbiological profile, prior use of antibiotics and risk factors for VAP acquisition.

RESULTS

Control and VAP group outcomes were, respectively, as follows: median TMV (days), 9 (interquartile range [IQR]: 5-15) and 23 (IQR: 15-37; p < 0.0001); median TICU (days), 12 (IQR: 8-21) and 27 (IQR: 17-42; p < 0.0001); median LHS (days), 33 (IQR: 18-64) and 46 (IQR: 25-90; p = 0.05); and in-ICU mortality, 38% (95% CI: 31-45) and 55% (95% CI: 42-67; p = 0.02). VAP was a predictor of in-ICU mortality (OR = 3.40; 95% CI: 1.54-7.48). TMV (OR = 2.27; 95% CI: 1.05-4.87) and prior use of antibiotics (OR = 1.07; 95% CI: 1.04-1.10) were risk factors for VAP. VAP did not affect in-hospital mortality. Acinetobacter spp. was the most common isolate (28%). Inappropriate empirical antibiotic therapy was administered in 48% of cases.

CONCLUSIONS

In this study, there was a high incidence of infection with resistant bacteria and inappropriate initial antibiotic therapy. Long TMV and prior use of antibiotics are risk factors for VAP.

Patterns of antimicrobial therapy in severe nosocomial infections: empiric choices, proportion of appropriate therapy, and adaptation rates--a multicentre, observational survey in critically ill patients

This prospective, observational multicentre (n=24) study investigated relationships between antimicrobial choices and rates of empiric appropriate or adequate therapy, and subsequent adaptation of therapy in 171 ICU patients with severe nosocomial infections. Appropriate antibiotic therapy was defined as in vitro susceptibility of the causative pathogen and clinical response to the agent administered. In non-microbiologically documented infections, therapy was considered adequate in the case of favourable clinical response <5 days. Patients had pneumonia (n=127; 66 ventilator-associated), intra-abdominal infection (n=23), and bloodstream infection (n=21). Predominant pathogens were Pseudomonas aeruginosa (n=29) Escherichia coli (n=26), Staphylococcus aureus (n=22), and Enterobacter aerogenes (n=21). In 49.6% of infections multidrug-resistant (MDR) bacteria were involved, mostly extended-spectrum beta-lactamase (EBSL)-producing Enterobacteriaceae and MDR non-fermenting Gram-negative bacteria. Prior antibiotic exposure and hospitalisation in a general ward prior to ICU admission were risk factors for MDR. Empiric therapy was appropriate/adequate in 63.7% of cases. Empiric schemes were classified according to coverage of (i) ESBL-producing Enterobacteriaceae and non-fermenting Gram-negative bacteria ("meropenem-based"), (ii) non-fermenting Gram-negative bacteria (schemes with an antipseudomonal agent), and (iii) first-line agents not covering ESBL-Enterobacteriaceae nor non-fermenting Gram-negative bacteria. Meropenem-based schemes allowed for significantly higher rates of appropriate/adequate therapy (p<0.001). This benefit remained when only patients without risk factors for MDR were considered (p=0.021). In 106 patients (61%) empiric therapy was modified: in 60 cases following initial inappropriate/inadequate therapy, in 46 patients in order to refine empiric therapy. In this study reflecting real-life practice, first-line use of meropenem provided significantly higher rates of the appropriate/adequate therapy, irrespective of presence of risk factors for MDR.

Review on pharmacokinetics and pharmacodynamics and the aging kidney

In people who are aged >65 years, pharmacokinetics are influenced more by the loss of kidney function than by the aging process of any other organ. A GFR of 30 to 60 ml/min, suggestive of stage 3 kidney disease, is observed in 15 to 30% of elderly people. Drug dosing must be adjusted to both changing pharmacokinetics and pharmacodynamics; the pharmacodynamics might be influenced by the aging of other organs, too. Using our NEPharm database, we extracted abstracts with pharmacokinetic parameters since 1999 from a weekly PubMed search. The recorded data were analyzed and compared with published recommendations on drug dosage and use in the elderly. Purely age-related changes in pharmacokinetic parameters were recorded from publications on 127 drugs. The analysis of our NEPharm records revealed an average (mean +/- SD) age-related prolongation of half-life of 1.39-fold (corresponding to +39 +/- 61%). Contrasting to common opinion, mean changes in clearance (-1 +/- 54%) and volume of distribution (+24 +/- 56%) were even less. The modest changes in pharmacokinetics do not suggest general dosage modifications in the elderly for most drugs. Changes in pharmacodynamics justify the common medication rule in the elderly-"start low + go slow"-especially for drugs that act on the central nervous system; however, in the case of anti-infective and anticancer therapy, the rule should be "hit hard = start high + go fast" to produce the target effect also in the elderly.