Impact of ceftazidime/avibactam versus best available therapy on mortality from infections caused by carbapenemase-producing Enterobacterales (CAVICOR study).

BACKGROUND: Infections caused by carbapenemase-producing Enterobacterales (CPE) are not well represented in pivotal trials with ceftazidime/avibactam. The best strategy for the treatment of these infections is unknown. METHODS: We conducted a multicentre retrospective observational study of patients who received ≥48 h of ceftazidime/avibactam or best available therapy (BAT) for documented CPE infections. The primary outcome was 30 day crude mortality. Secondary outcomes were 21 day clinical response and microbiological response. A multivariate logistic regression model was used to identify factors predictive of 30 day crude mortality. A propensity score to receive treatment with ceftazidime/avibactam was used as a covariate in the analysis. RESULTS: The cohort included 339 patients with CPE infections. Ceftazidime/avibactam treatment was used in 189 (55.8%) patients and 150 (44.2%) received BAT at a median of 2 days after diagnosis of infection. In multivariate analysis, ceftazidime/avibactam treatment was associated with survival (OR 0.41, 95% CI 0.20-0.80; P = 0.01), whereas INCREMENT-CPE scores of >7 points (OR 2.57, 95% CI 1.18-1.5.58; P = 0.01) and SOFA score (OR 1.20, 95% CI 1.08-1.34; P = 0.001) were associated with higher mortality. In patients with INCREMENT-CPE scores of >7 points, ceftazidime/avibactam treatment was associated with lower mortality compared with BAT (16/73, 21.9% versus 23/49, 46.9%; P = 0.004). Ceftazidime/avibactam was also an independent factor of 21 day clinical response (OR 2.43, 95% CI 1.16-5.12; P = 0.02) and microbiological eradication (OR 0.40, 95% CI 0.18-0.85; P = 0.02). CONCLUSIONS: Ceftazidime/avibactam is an effective alternative for the treatment of CPE infections, especially in patients with INCREMENT-CPE scores of >7 points. A randomized controlled trial should confirm these findings.

Awake prone positioning does not reduce the risk of intubation in COVID-19 treated with high-flow nasal oxygen therapy: a multicenter, adjusted cohort study.

BACKGROUND: Awake prone positioning (awake-PP) in non-intubated coronavirus disease 2019 (COVID-19) patients could avoid endotracheal intubation, reduce the use of critical care resources, and improve survival. We aimed to examine whether the combination of high-flow nasal oxygen therapy (HFNO) with awake-PP prevents the need for intubation when compared to HFNO alone. METHODS: Prospective, multicenter, adjusted observational cohort study in consecutive COVID-19 patients with acute respiratory failure (ARF) receiving respiratory support with HFNO from 12 March to 9 June 2020. Patients were classified as HFNO with or without awake-PP. Logistic models were fitted to predict treatment at baseline using the following variables: age, sex, obesity, non-respiratory Sequential Organ Failure Assessment score, APACHE-II, C-reactive protein, days from symptoms onset to HFNO initiation, respiratory rate, and peripheral oxyhemoglobin saturation. We compared data on demographics, vital signs, laboratory markers, need for invasive mechanical ventilation, days to intubation, ICU length of stay, and ICU mortality between HFNO patients with and without awake-PP. RESULTS: A total of 1076 patients with COVID-19 ARF were admitted, of which 199 patients received HFNO and were analyzed. Fifty-five (27.6%) were pronated during HFNO; 60 (41%) and 22 (40%) patients from the HFNO and HFNO + awake-PP groups were intubated. The use of awake-PP as an adjunctive therapy to HFNO did not reduce the risk of intubation [RR 0.87 (95% CI 0.53-1.43), p = 0.60]. Patients treated with HFNO + awake-PP showed a trend for delay in intubation compared to HFNO alone [median 1 (interquartile range, IQR 1.0-2.5) vs 2 IQR 1.0-3.0] days (p = 0.055), but awake-PP did not affect 28-day mortality [RR 1.04 (95% CI 0.40-2.72), p = 0.92]. CONCLUSION: In patients with COVID-19 ARF treated with HFNO, the use of awake-PP did not reduce the need for intubation or affect mortality.

Rationale and Study Design for an Individualized Perioperative Open Lung Ventilatory Strategy in Patients on One-Lung Ventilation (iPROVE-OLV).

OBJECTIVE: The aim of this clinical trial is to examine whether it is possible to reduce postoperative complications using an individualized perioperative ventilatory strategy versus using a standard lung-protective ventilation strategy in patients scheduled for thoracic surgery requiring one-lung ventilation. DESIGN: International, multicenter, prospective, randomized controlled clinical trial. SETTING: A network of university hospitals. PARTICIPANTS: The study comprises 1,380 patients scheduled for thoracic surgery. INTERVENTIONS: The individualized group will receive intraoperative recruitment maneuvers followed by individualized positive end-expiratory pressure (open lung approach) during the intraoperative period plus postoperative ventilatory support with high-flow nasal cannula, whereas the control group will be managed with conventional lung-protective ventilation. MEASUREMENTS AND MAIN RESULTS: Individual and total number of postoperative complications, including atelectasis, pneumothorax, pleural effusion, pneumonia, acute lung injury; unplanned readmission and reintubation; length of stay and death in the critical care unit and in the hospital will be analyzed for both groups. The authors hypothesize that the intraoperative application of an open lung approach followed by an individual indication of high-flow nasal cannula in the postoperative period will reduce pulmonary complications and length of hospital stay in high-risk surgical patients.

Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies.

Sepsis and septic shock are associated with high mortality, with diagnosis and treatment remaining a challenge for clinicians. Their management classically encompasses hemodynamic resuscitation, antibiotic treatment, life support, and focus control; however, there are aspects that have changed. This narrative review highlights current and avant-garde methods of handling patients experiencing septic shock based on the experience of its authors and the best available evidence in a context of uncertainty. Following the first recommendation of the Surviving Sepsis Campaign guidelines, it is recommended that specific sepsis care performance improvement programs are implemented in hospitals, i.e., "Sepsis Code" programs, designed ad hoc, to achieve this goal. Regarding hemodynamics, the importance of perfusion and hemodynamic coherence stand out, which allow for the recognition of different phenotypes, determination of the ideal time for commencing vasopressor treatment, and the appropriate fluid therapy dosage. At present, this is not only important for the initial timing, but also for de-resuscitation, which involves the early weaning of support therapies, directed elimination of fluids, and fluid tolerance concept. Finally, regarding blood purification therapies, those aimed at eliminating endotoxins and cytokines are attractive in the early management of patients in septic shock.

Sepsis Stewardship: The Puzzle of Antibiotic Therapy in the Context of Individualization of Decision Making.

The main recent change observed in the field of critical patient infection has been universal awareness of the need to make better use of antimicrobials, especially for the most serious cases, beyond the application of simple and effective formulas or rigid protocols. The increase in resistant microorganisms, the quantitative increase in major surgeries and interventional procedures in the highest risk patients, and the appearance of a significant number of new antibiotics in recent years (some very specifically directed against certain mechanisms of resistance and others with a broader spectrum of applications) have led us to shift our questions from "what to deal with" to "how to treat". There has been controversy about how best to approach antibiotic treatment of complex cases of sepsis. The individualized and adjusted dosage, the moment of its administration, the objective, and the selection of the regimen are pointed out as factors of special relevance in a critically ill patient where the frequency of resistant microorganisms, especially among the Enterobacterales group, and the emergence of multiple and diverse antibiotic treatment alternatives have made the appropriate choice of antibiotic treatment more complex, requiring a constant updating of knowledge and the creation of multidisciplinary teams to confront new infections that are difficult to treat. In this article, we have reviewed the phenomenon of the emergence of resistance to antibacterials and we have tried to share some of the ideas, such as stewardship, sparing carbapenems, and organizational, microbiological, pharmacological, and knowledge tools, that we have considered most useful and effective for individualized decision making that takes into account the current context of multidrug resistance. The greatest challenge, therefore, of decision making in this context lies in determining an effective, optimal, and balanced empirical antibiotic treatment.

Decrease in Mortality after the Implementation of a Hospital Model to Improve Performance in Sepsis Care: Princess Sepsis Code.

Sepsis is a time-dependent disease whose prognosis is influenced by early diagnosis and therapeutic measures. Mortality from sepsis remains high, and for this reason, the guidelines of the Surviving Sepsis Campaign recommend establishing specific care programs aimed at patients with sepsis. We present the results of the application of a hospital model to improve performance in sepsis care, called Princess Sepsis Code, with the aim of reducing mortality. A retrospective study was conducted using clinical, epidemiological, and outcome variables in patients diagnosed with sepsis from 2015 to 2022. A total of 2676 patients were included, 32% of whom required admission to the intensive care unit, with the most frequent focus of the sepsis being abdominal. Mortality in 2015, at the beginning of the sepsis code program, was 24%, with a declining rate noted over the study period, with mortality reaching 17% in 2022. In the multivariate analysis, age > 70 years, respiratory rate > 22 rpm, deterioration in the level of consciousness, serum lactate > 2 mmol/L, creatinine > 1.6 mg/dL, and the focus of the sepsis were identified as variables independently related to mortality. The implementation of the Princess Sepsis Code care model reduces the mortality of patients exhibiting sepsis and septic shock.

Individualised, perioperative open-lung ventilation strategy during one-lung ventilation (iPROVE-OLV): a multicentre, randomised, controlled clinical trial.

BACKGROUND: It is uncertain whether individualisation of the perioperative open-lung approach (OLA) to ventilation reduces postoperative pulmonary complications in patients undergoing lung resection. We compared a perioperative individualised OLA (iOLA) ventilation strategy with standard lung-protective ventilation in patients undergoing thoracic surgery with one-lung ventilation. METHODS: This multicentre, randomised controlled trial enrolled patients scheduled for open or video-assisted thoracic surgery using one-lung ventilation in 25 participating hospitals in Spain, Italy, Turkey, Egypt, and Ecuador. Eligible adult patients (age ≥18 years) were randomly assigned to receive iOLA or standard lung-protective ventilation. Eligible patients (stratified by centre) were randomly assigned online by local principal investigators, with an allocation ratio of 1:1. Treatment with iOLA included an alveolar recruitment manoeuvre to 40 cm H2O of end-inspiratory pressure followed by individualised positive end-expiratory pressure (PEEP) titrated to best respiratory system compliance, and individualised postoperative respiratory support with high-flow oxygen therapy. Participants allocated to standard lung-protective ventilation received combined intraoperative 4 cm H2O of PEEP and postoperative conventional oxygen therapy. The primary outcome was a composite of severe postoperative pulmonary complications within the first 7 postoperative days, including atelectasis requiring bronchoscopy, severe respiratory failure, contralateral pneumothorax, early extubation failure (rescue with continuous positive airway pressure, non-invasive ventilation, invasive mechanical ventilation, or reintubation), acute respiratory distress syndrome, pulmonary infection, bronchopleural fistula, and pleural empyema. Due to trial setting, data obtained in the operating and postoperative rooms for routine monitoring were not blinded. At 24 h, data were acquired by an investigator blinded to group allocation. All analyses were performed on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, NCT03182062, and is complete. FINDINGS: Between Sept 11, 2018, and June 14, 2022, we enrolled 1380 patients, of whom 1308 eligible patients (670 [434 male, 233 female, and three with missing data] assigned to iOLA and 638 [395 male, 237 female, and six with missing data] to standard lung-protective ventilation) were included in the final analysis. The proportion of patients with the composite outcome of severe postoperative pulmonary complications within the first 7 postoperative days was lower in the iOLA group compared with the standard lung-protective ventilation group (40 [6%] vs 97 [15%], relative risk 0·39 [95% CI 0·28 to 0·56]), with an absolute risk difference of -9·23 (95% CI -12·55 to -5·92). Recruitment manoeuvre-related adverse events were reported in five patients. INTERPRETATION: Among patients subjected to lung resection under one-lung ventilation, iOLA was associated with a reduced risk of severe postoperative pulmonary complications when compared with conventional lung-protective ventilation. FUNDING: Instituto de Salud Carlos III and the European Regional Development Funds.

Development and validation of a delirium risk prediction preoperative model for cardiac surgery patients (DELIPRECAS): An observational multicentre study.

STUDY OBJECTIVE: To develop and validate a delirium risk prediction preoperative model for patients undergoing cardiac surgery. DESIGN: Observational prospective multicentre study. SETTING: Six intensive care units in Spain. PATIENTS: 689 patients undergoing cardiac surgery consecutively, aged ≥18 years. MEASUREMENTS: The primary outcome measure was the development of delirium, diagnosed using the Confusion Assessment Method in Intensive Care Units (CAM-ICU), during the stay in the intensive care unit after cardiac surgery. MAIN RESULTS: The model was developed with 345 consecutive patients undergoing cardiac surgery at six hospitals and validated with another 344 patients from the same hospitals. The prediction model contained four preoperative risk factors: age over 65 years, Mini-Mental State Examination (MMSE) score of 25-26 points (possible impairment of cognitive function) or < 25 (impairment of cognitive function), insomnia needing medical treatment and low physical activity (walk less than 30 min a day). The model had an area under the receiver operating characteristics curve of 0.825 (95% confidence interval: 0.76-0.89). The validation resulted in an area under the curve of 0.79 (0.73-0.85) and the pooled area under the receiver operating characteristics curve (n = 689) was 0.81 (0.76-0.85). We stratified patients in groups of low (0%-20%), moderate (> 20%-40%), high (> 40%-60%) and very high (> 60%) risk of developing delirium, with a positive and negative predictive value for the very high risk group of 70.97% and 85.56%, respectively. CONCLUSION: The DELIPRECAS model (DELIrium PREvention CArdiac Surgery), consisting of four well-defined clinical risk factors, can predict in the preoperative period the risk of developing postoperative delirium in patients undergoing cardiac surgery. An automatic version of the risk calculator is available.

Critically ill patients with community-onset intraabdominal infections: Influence of healthcare exposure on resistance rates and mortality.

The concept of healthcare-associated infections (as opposed to hospital-acquired infections) in intraabdominal infections (IAIs) is scarcely supported by data in the literature. The aim of the present study was to analyse community-onset IAIs (non-postoperative/non-nosocomial) in patients admitted to intensive care units (ICUs), to investigate differences in resistance patterns linked to healthcare exposure and mortality-associated factors. A one-year prospective observational study (17 Spanish ICUs) was performed distributing cases as healthcare-associated infections (HCAI), community-acquired infections (CAI) and immunocompromised patients (ICP). Bacteria producing extended-spectrum ß-lactamases (ESBL) and/or carbapenemase (CPE), high-level aminoglycoside- and/or methicillin- and/or vancomycin- resistance were considered antimicrobial resistant (AMR). Mortality-associated factors were identified by regression multivariate analysis. Of 345 patients included (18.8% HCAI, 6.1% ICP, 75.1% CAI), 51.6% presented generalized peritonitis; 32.5% were >75 years (55.4% among HCAI). Overall, 11.0% cases presented AMR (7.0% ESBL- and/or CPE), being significantly higher in HCAI (35.4%) vs. CAI (5.8%) (p<0.001) vs. ICP (0%) (p = 0.003). Overall 30-day mortality was 14.5%: 23.1% for HCAI and 11.6% for CAI (p = 0.016). Mortality (R2 = 0.262, p = 0.021) was positively associated with age >75 years (OR = 6.67, 95%CI = 2.56-17.36,p<0.001), Candida isolation (OR = 3.05, 95%CI = 1.18-7.87,p = 0.022), and SAPS II (per-point, OR = 1.08, 95%CI = 1.05-1.11, p<0.001) and negatively with biliary infections (OR = 0.06, 95%CI = 0.01-0.48,p = 0.008). In this study, the antimicrobial susceptibility pattern of bacteria isolated from patients with healthcare contact was shifted to resistance, suggesting the need for consideration of the healthcare category (not including hospital-acquired infections) for severe IAIs. 30-day mortality was positively related with age >75 years, severity and Candida isolation but not with AMR.

Biomarkers (Procalcitonin, C Reactive Protein, and Lactate) as Predictors of Mortality in Surgical Patients with Complicated Intra-Abdominal Infection.

BACKGROUND: An accurate and readily available biomarker for identifying patients with complicated intra-abdominal infection needing special attention in critical care units because of their greater risk of dying would be of value for intensivists. METHODS: A multi-center, observational, retrospective study explored blood lactate, C-reactive protein (CRP), and procalcitonin (PCT) concentrations, and also Sequential Organ Failure Assessment (SOFA) and Simplified Acute Physiology Score (SAPS II) as mortality predictors in all adult patients with complicated intra-abdominal infection (cIAI) admitted to Surgical Critical Care Units (SCCUs) for ≥48 h in four Spanish hospitals (June 2012-June 2013). Logistic regression models (step-wise procedure) were constructed using as dependent variables "intra-SCCU mortality" or "overall mortality," and variables showing differences (p≤0.1) in bivariate analyses as independent variables. RESULTS: One hundred twenty-one cases were included. Mortality intra-SCCU (R(2)=0.189, p=0.001) was associated with SAPS II (categorized as high if ≥47) (OR=9.55; 95% CI, 1.09-83.85; p=0.042) and 24 h-lactate (≥5.87 categorized as high) (OR=6.90; 95% CI, 1.28-37.08). Overall mortality (R(2)=0.275, p=0.001) was associated with peak PCT (≥100 categorized as high) (OR=11.28; 95% CI, 1.80-70.20), peak lactate (≥1.8 categorized as high) (OR=8.86; 95% CI, 1.51-52.10) and SOFA at admission (≥7 categorized as high) (OR=8.14; 95% CI, 1.69-39.20), but was predicted better (R(2)=0.275, p=0.001) by a single dummy variable (high peak PCT-high peak lactate concentrations) (OR=99.11; 95% CI, 5.21-1885.97; p=0.002). CONCLUSIONS: In the present study, SAPS II and 24 h-lactate concentrations predicted intra-SCCU mortality whereas overall mortality was predicted better by concurrent high PCT and lactate peak concentrations than by clinical scores or by each biomarker separately.

Procalcitonin-guided therapy may reduce length of antibiotic treatment in intensive care unit patients with secondary peritonitis: A multicenter retrospective study.

PURPOSE: Because procalcitonin (PCT) might be surrogate for antimicrobial discontinuation in general intensive care units (ICUs), this study explored its use for secondary peritonitis in 4 surgical ICUs (SICUs). METHODS: A retrospective study including all consecutive patients with secondary peritonitis, controlled infection source, requiring surgery, and at least 48-hour SICU admission was performed (June 2012-June 2013). Patients were divided following notations in medical records into PCT-guided (notation of PCT-based antibiotic discontinuation) and non-PCT-guided (no notation) groups. RESULTS: A total of 121 patients (52 PCT-guided, 69 non-PCT-guided) were included. No differences in clinical scores, biomarkers, or septic shock (30 [57.7%] PCT-guided vs 40 [58.0%] non-PCT-guided) were found. Length of intra-SICU (median, 5.0 days; both groups) or in-hospital (median, 20.0 vs 17.5 days) stay, and mortality intra-SICU (9.6% vs 13.0%), 28-day (15.4% vs 20.3%), or in-hospital (19.2% vs 29.0%) were not significantly different (PCT-guided vs non-PCT-guided). In septic shock patients, no mortality differences were found (PCT-guided vs non-PCT-guided): 16.7% vs 22.5% (intra-SICU), 26.7% vs 32.5% (28-day), and 33.3% vs 42.5% (in-hospital). Treatment was shorter in the PCT-guided group (5.1 ±2.1 vs 10.2 ± 3.7 days, P < .001), without differences between patients with and without septic shock. CONCLUSION: Procalcitonin guidance produced 50% reduction in antibiotic duration (P < .001, log-rank test).

A practice-based observational study identifying factors associated with the use of high-dose tigecycline in the treatment of secondary peritonitis in severely ill patients.

INTRODUCTION: Based on tigecycline linear pharmacokinetic/pharmacodynamics, dose increases have been advocated to maximise activity especially when severe infections with high bacterial load and/or multidrug resistance are suspected. This practice-based observational study explored factors associated with tigecycline administration (100 mg/12h, 200 mg loading dose) in severely ill patients with complicated intra-abdominal infection (cIAI) admitted to four Surgical Critical Care Units (SCCUs). METHODS: Medical records of all consecutive adult patients with cIAI and controlled infection source requiring surgery and admission for ≥ 48 h to SCCU were reviewed and divided into patients treated with a regimen including tigecycline (tigecycline group) and those that not (control group). A logistic regression model was performed using "tigecycline administration" (dependent variable) and variables showing differences (p ≤ 0.1) in bivariate analyses (independent variables). RESULTS: One hundred and twenty one patients were included. In the tigecycline group, higher percentage of patients (vs. controls) presented colon as surgical site (66.7% vs. 41.8%, p = 0.006), nosocomial infection (55.6% vs. 26.9%, p = 0.001), mechanical ventilation (48.1% vs. 28.4%, p = 0.025), chronic renal replacement therapy (40.7% vs. 19.4%, p =0.008), septic shock (72.2% vs. 46.3%, p = 0.004), and higher values of SAPS II (48.0 ± 15.0 vs. 39.6 ± 15.5, p = 0.003), SOFA at admission (7.0 ± 3.3 vs. 5.5 ± 3.7, p = 0.020), lactate-24h (2.5 ± 2.8 vs. 1.6 ± 0.9, p = 0.029) and CRP-72 h (207.4 ± 87.9 vs. 163.7 ± 76.8, p = 0.021). In the multivariate analysis (R2 = 0.187, p < 0.001) nosocomial infection (OR = 7.721; 95%CI = 2.193, 27.179; p = 0.001), colon as infection site (OR = 4.338; 95%CI = 1.432, 13.145; p = 0.009) and CRP-72 h (OR = 1.009 per-unit; 95%CI = 1.002, 1.016; p = 0.012) were associated with tigecycline administration. CONCLUSIONS: In severely ill patients with cIAI, high-dose tigecycline administration was associated with nosocomial origin of cIAI and colon as source infection site.

Rationale and study design for an individualized perioperative open lung ventilatory strategy (iPROVE): study protocol for a randomized controlled trial.

BACKGROUND: Postoperative pulmonary and non-pulmonary complications are common problems that increase morbidity and mortality in surgical patients, even though the incidence has decreased with the increased use of protective lung ventilation strategies. Previous trials have focused on standard strategies in the intraoperative or postoperative period, but without personalizing these strategies to suit the needs of each individual patient and without considering both these periods as a global perioperative lung-protective approach. The trial presented here aims at comparing postoperative complications when using an individualized ventilatory management strategy in the intraoperative and immediate postoperative periods with those when using a standard protective ventilation strategy in patients scheduled for major abdominal surgery. METHODS: This is a comparative, prospective, multicenter, randomized, and controlled, four-arm trial that will include 1012 patients with an intermediate or high risk for postoperative pulmonary complications. The patients will be divided into four groups: (1) individualized perioperative group: intra- and postoperative individualized strategy; (2) intraoperative individualized strategy + postoperative continuous positive airway pressure (CPAP); (3) intraoperative standard ventilation + postoperative CPAP; (4) intra- and postoperative standard strategy (conventional strategy). The primary outcome is a composite analysis of postoperative complications. DISCUSSION: The Individualized Perioperative Open-lung Ventilatory Strategy (iPROVE) is the first multicenter, randomized, and controlled trial to investigate whether an individualized perioperative approach prevents postoperative pulmonary complications. TRIAL REGISTRATION: Registered on 5 June 2014 with identification no. NCT02158923 .

Bugs, hosts and ICU environment: countering pan-resistance in nosocomial microbiota and treating bacterial infections in the critical care setting.

ICUs are areas where resistance problems are the largest, and these constitute a major problem for the intensivist's clinical practice. Main resistance phenotypes among nosocomial microbiota are (i) vancomycin-resistance/heteroresistance and tolerance in grampositives (MRSA, enterococci) and (ii) efflux pumps/enzymatic resistance mechanisms (ESBLs, AmpC, metallo-betalactamases) in gramnegatives. These phenotypes are found at different rates in pathogens causing respiratory (nosocomial pneumonia/ventilator-associated pneumonia), bloodstream (primary bacteremia/catheter-associated bacteremia), urinary, intraabdominal and surgical wound infections and endocarditis in the ICU. New antibiotics are available to overcome non-susceptibility in grampositives; however, accumulation of resistance traits in gramnegatives has led to multidrug resistance, a worrisome problem nowadays. This article reviews microorganism/infection risk factors for multidrug resistance, suggesting adequate empirical treatments. Drugs, patient and environmental factors all play a role in the decision to prescribe/recommend antibiotic regimens in the specific ICU patient, implying that intensivists should be familiar with available drugs, environmental epidemiology and patient factors.

Bugs, hosts and ICU environment: countering pan-resistance in nosocomial microbiota and treating bacterial infections in the critical care setting.

ICUs are areas where resistance problems are the largest, and they constitutes a major problem for the intensivist's clinical practice. Main resistance phenotypes among nosocomial microbiota are: i) vancomycin-resistance/heteroresistance and tolerance in grampositives (MRSA, enterococci) and ii) efflux pumps/enzymatic resistance mechanisms (ESBLs, AmpC, metallobetalactamases) in gramnegatives. These phenotypes are found at different rates in pathogens causing respiratory (nosocomial pneumonia/ventilator-associated pneumonia), bloodstream (primary bacteremia/catheter-associated bacteremia), urinary, intraabdominal and surgical wound infections and endocarditis in the ICU. New antibiotics are available to overcome non-susceptibility in grampositives; however, accumulation of resistance traits in gramnegatives has lead to multidrug resistance, a worrisome problem nowadays. This article reviews by microorganism/infection risk factors for multidrug resistance, suggesting adequate empirical treatments. Drugs, patient and environmental factors all play a role in the decision to prescribe/recommend antibiotic regimens in the specific ICU patient, implying that intensivists should be familiar with available drugs, environmental epidemiology and patient factors.