Building a continuous multicenter infection surveillance system in the intensive care unit: findings from the initial data set of 9,493 patients from 71 Italian intensive care units

Naringin: A flavanone with a multifaceted target against sepsis-associated organ injuries

BACKGROUND

Sepsis causes multiple organ dysfunctions and raises mortality and morbidity rates through a dysregulated host response to infection. Despite the growing research interest over the last few years, no satisfactory treatment exists. Naringin, a naturally occurring bioflavonoid with vast therapeutic potential in citrus fruits and Chinese herbs, has received much attention for treating sepsis-associated multiple organ dysfunctions.

PURPOSE

The review describes preclinical evidence of naringin from 2011 to 2024, particularly emphasizing the mechanism of action mediated by naringin against sepsis-associated specific injuries. The combination therapy, safety profile, drug interactions, recent advancements in formulation, and future perspectives of naringin are also discussed.

METHODS

In vivo and in vitro studies focusing on the potential role of naringin and its mechanism of action against sepsis-associated organ injuries were identified and summarised in the present manuscript, which includes contributions from 2011 to 2024. All the articles were extracted from the Medline database using PubMed, Science Direct, and Web of Science with relevant keywords.

RESULTS

Research findings revealed that naringin modulates many signaling cascades, such as Rho/ROCK and PPAR/STAT1, PIP3/AKT and KEAP1/Nrf2, and IkB/NF-kB and MAPK/Nrf2/HO-1, to potentially protect against sepsis-induced intestinal, cardiac, and lung injury, respectively. Furthermore, naringin treatment exhibits anti-inflammatory, anti-apoptotic, and antioxidant action against sepsis harm, highlighting naringin's promising effects in septic settings. Naringin could be employed as a treatment against sepsis, based on studies on combination therapy, synergistic effects, and toxicological investigation that show no reported severe side effects.

CONCLUSION

Naringin might be a promising therapeutic approach for preventing sepsis-induced multiple organ failure. Naringin should be used alongside other therapeutic therapies with caution despite its great therapeutic potential and lower toxicity. Nonetheless, clinical studies are required to comprehend the therapeutic benefits of naringin against sepsis.

Bacterial and fungal infections: a frequent and deadly complication among critically ill acute liver failure patients

BACKGROUND

Acute liver failure (ALF) is a rare but life-threatening condition mostly requiring intensive care unit (ICU) admission. ALF induces immune disorders and may promote infection acquisition. However, the clinical spectrum and impact on patients' prognosis remain poorly explored.

METHODS

We conducted a retrospective single-centre study on patients admitted for ALF to the ICU of a referral University Hospital from 2000 to 2021. Baseline characteristics and outcomes according to the presence of infection until day 28 were analysed. Risk factors for infection were determined using logistic regression. The impact of infection on 28-day survival was assessed using the proportional hazard Cox model.

RESULTS

Of the 194 patients enrolled, 79 (40.7%) underwent infection: community-acquired, hospital-acquired before ICU and ICU-acquired before/without and after transplant in 26, 23, 23 and 14 patients, respectively. Most infections were pneumonia (41.4%) and bloodstream infection (38.8%). Of a total of 130 microorganisms identified, 55 were Gram-negative bacilli (42.3%), 48 Gram-positive cocci (36.9%) and 21 were fungi (16.2%). Obesity (OR 3.77 [95% CI 1.18-14.40]; p = .03) and initial mechanical ventilation (OR 2.26 [95% CI 1.25-4.12]; p = .007) were independent factors associated with overall infection. SAPSII > 37 (OR 3.67 [95% CI 1.82-7.76], p < .001) and paracetamol aetiology (OR 2.10 [95% CI 1.06-4.22], p = .03) were independently associated with infection at admission to ICU. On the opposite, paracetamol aetiology was associated with lower risk of ICU-acquired infection (OR 0.37 [95% CI 0.16-0.81], p = .02). Patients with any type of infection had lower day 28 survival rates (57% versus 73%; HR 1.65 [1.01-2.68], p = .04). The presence of infection at ICU admission (p = .04), but not ICU-acquired infection, was associated with decreased survival.

CONCLUSIONS

The prevalence of infection is high in ALF patients which is associated with a higher risk of death. Further studies assessing the use of early antimicrobial therapy are needed.

Costo-efficacia di IMI/CIL/REL rispetto a CMS+IMI per il trattamento di infezioni batteriche Gram-negative non sensibili ai carbapenemi

Objective:

The objective of this analysis was to evaluate the cost-effectiveness of imipenem/cilastatin/relebactam compared to colistin-imipenem in the treatment of hospitalized patients with Gram-negative bacterial infections caused by imipenem-resistant pathogens. The perspective was both that of the National Health Service (NHS) and the social one.

Methodology:

A mixed model was developed to simulate a cohort of patients capable of highlighting the impacts of the disease on the quality of life and the absorption of economic resources of the patients in analysis. Modelled patients were those with hospital-acquired bacterial pneumonia/ventilator-associated bacterial pneumonia (HABP/VABP), complicated intra-abdominal infection (cIAI) or complicated urinal tract infection (cUTI) caused by carbapenem-resistant Gram-negative (GN) pathogens. The model begins with a short-term decision tree describing possible treatment routes and outcomes for patients during the hospitalization period. Patients who are healed in the decision tree enter the long-term Markov model, designed to capture the follow-up costs and health-related quality of life (HRQL) of patients healed over their lifetime.

Results:

The analysis, conducted on a hypothetical cohort of 1,000 patients, highlights how the use of imipenem/cilastatin/relebactam is advantageous both in terms of diagnosis and treatment in the short term and in terms of cost-effectiveness. In fact, it is dominant compared to colistin-imipenem both in the NHS and in the social perspective since, compared to an average saving of € 2,800.15 and € 3,174.63 respectively, it would generate an increase of 4.76 years of life and of 4.12 QALYs per patient.

What intensive care registries can teach us about outcomes

PURPOSE OF REVIEW

Critical care registries are synonymous with measurement of outcomes following critical illness. Their ability to provide longitudinal data to enable benchmarking of outcomes for comparison within units over time, and between units, both regionally and nationally is a key part of the evaluation of quality of care and ICU performance as well as a better understanding of case-mix. This review aims to summarize literature on outcome measures currently being reported in registries internationally, describe the current strengths and challenges with interpreting existing outcomes and highlight areas where registries may help improve implementation and interpretation of both existing and new outcome measures.

RECENT FINDINGS

Outcomes being widely reported through ICU registries include measures of survival, events of interest, patient-reported outcomes and measures of resource utilization (including cost). Despite its increasing adoption, challenges with quality of reporting of outcomes measures remain. Measures of short-term survival are feasible but those requiring longer follow-ups are increasingly difficult to interpret given the evolving nature of critical care in the context of acute and chronic disease management. Furthermore, heterogeneity in patient populations and in healthcare organisations in different settings makes use of outcome measures for international benchmarking at best complex, requiring substantial advances in their definitions and implementation to support those seeking to improve patient care.

SUMMARY

Digital registries could help overcome some of the current challenges with implementing and interpreting ICU outcome data through standardization of reporting and harmonization of data. In addition, ICU registries could be instrumental in enabling data for feedback as part of improvement in both patient-centred outcomes and in service outcomes; notably resource utilization and efficiency.

A scoping review of registry captured indicators for evaluating quality of critical care in ICU

BACKGROUND

Excess morbidity and mortality following critical illness is increasingly attributed to potentially avoidable complications occurring as a result of complex ICU management (Berenholtz et al., J Crit Care 17:1-2, 2002; De Vos et al., J Crit Care 22:267-74, 2007; Zimmerman J Crit Care 1:12-5, 2002). Routine measurement of quality indicators (QIs) through an Electronic Health Record (EHR) or registries are increasingly used to benchmark care and evaluate improvement interventions. However, existing indicators of quality for intensive care are derived almost exclusively from relatively narrow subsets of ICU patients from high-income healthcare systems. The aim of this scoping review is to systematically review the literature on QIs for evaluating critical care, identify QIs, map their definitions, evidence base, and describe the variances in measurement, and both the reported advantages and challenges of implementation.

METHOD

We searched MEDLINE, EMBASE, CINAHL, and the Cochrane libraries from the earliest available date through to January 2019. To increase the sensitivity of the search, grey literature and reference lists were reviewed. Minimum inclusion criteria were a description of one or more QIs designed to evaluate care for patients in ICU captured through a registry platform or EHR adapted for quality of care surveillance.

RESULTS

The search identified 4780 citations. Review of abstracts led to retrieval of 276 full-text articles, of which 123 articles were accepted. Fifty-one unique QIs in ICU were classified using the three components of health care quality proposed by the High Quality Health Systems (HQSS) framework. Adverse events including hospital acquired infections (13.7%), hospital processes (54.9%), and outcomes (31.4%) were the most common QIs identified. Patient reported outcome QIs accounted for less than 6%. Barriers to the implementation of QIs were described in 35.7% of articles and divided into operational barriers (51%) and acceptability barriers (49%).

CONCLUSIONS

Despite the complexity and risk associated with ICU care, there are only a small number of operational indicators used. Future selection of QIs would benefit from a stakeholder-driven approach, whereby the values of patients and communities and the priorities for actionable improvement as perceived by healthcare providers are prioritized and include greater focus on measuring discriminable processes of care.

Epidemiology and burden of sepsis acquired in hospitals and intensive care units: a systematic review and meta-analysis

PURPOSE

Sepsis is recognized as a global public health problem, but the proportion due to hospital-acquired infections remains unclear. We aimed to summarize the epidemiological evidence related to the burden of hospital-acquired (HA) and ICU-acquired (ICU-A) sepsis.

METHODS

We searched MEDLINE, Embase and the Global Index Medicus from 01/2000 to 03/2018. We included studies conducted hospital-wide or in intensive care units (ICUs), including neonatal units (NICUs), with data on the incidence/prevalence of HA and ICU-A sepsis and the proportion of community and hospital/ICU origin. We did random-effects meta-analyses to obtain pooled estimates; inter-study heterogeneity and risk of bias were assessed.

RESULTS

Of the 13,239 studies identified, 51 met the inclusion criteria; 22 were from low- and middle-income countries. Twenty-eight studies were conducted in ICUs, 13 in NICUs, and ten hospital-wide. The proportion of HA sepsis among all hospital-treated sepsis cases was 23.6% (95% CI 17-31.8%, range 16-36.4%). In the ICU, 24.4% (95% CI 16.7-34.2%, range 10.3-42.5%) of cases of sepsis with organ dysfunction were acquired during ICU stay and 48.7% (95% CI 38.3-59.3%, range 18.7-69.4%) had a hospital origin. The pooled hospital incidence of HA sepsis with organ dysfunction per 1000 patients was 9.3 (95% CI 7.3-11.9, range 2-20.6)). In the ICU, the pooled incidence of HA sepsis with organ dysfunction per 1000 patients was 56.5 (95% CI 35-90.2, range 9.2-254.4) and it was particularly high in NICUs. Mortality of ICU patients with HA sepsis with organ dysfunction was 52.3% (95% CI 43.4-61.1%, range 30.1-64.6%). There was a significant inter-study heterogeneity. Risk of bias was low to moderate in ICU-based studies and moderate to high in hospital-wide and NICU studies.

CONCLUSION

HA sepsis is of major public health importance, and the burden is particularly high in ICUs. There is an urgent need to improve the implementation of global and local infection prevention and management strategies to reduce its high burden among hospitalized patients.

Host-pathogen interaction during mechanical ventilation: systemic or compartmentalized response?

Patients admitted to the intensive care unit (ICU) often require invasive mechanical ventilation. Ventilator-associated lower respiratory tract infections (VA-LRTI), either ventilator-associated tracheobronchitis (VAT) or ventilator-associated pneumonia (VAP), are the most common complication among this patient cohort. VAT and VAP are currently diagnosed and treated as separate entities, viewed as binary disease elements despite an inherent subjectivity in distinguishing them clinically. This paper describes a new approach to pulmonary infections in critically ill patients. Our conjecture is that the host-pathogen interaction during mechanical ventilation determines a local compartmentalized or systemic de-compartmentalized response, based on host immunity and inflammation, and the pathogenic potential of the infecting organism. This compartmentalized or de-compartmentalized response establishes disease severity along a continuum of colonization, VAT or VAP. This change in approach is underpinned by the dissemination hypothesis, which acknowledges the role of immune and inflammatory systems in determining host response to pathogenic organisms in the lower respiratory tract. Those with intact immune and inflammatory pathways may limit infection to a compartmentalized VAT, while immunosuppressed mechanically ventilated patients are at greater risk of a de-compartmentalized VAP. Taking this model from the realm of theory to the bedside will require a greater understanding of inflammatory and immune pathways, and the development of novel disease-specific biomarkers and diagnostic techniques. Advances will lead to early initiation of optimal bespoke antimicrobial therapy, where the intensity and duration of therapy are tailored to clinical, immune and biomarker response. This approach will benefit towards a personalized treatment.

How Can We Distinguish Ventilator-Associated Tracheobronchitis from Pneumonia?

Ventilator-associated tracheobronchitis (VAT) might represent an intermediate process between lower respiratory tract colonization and ventilator-associated pneumonia (VAP), or even a less severe spectrum of VAP. There is an urgent need for new concepts in the arena of ventilator-associated lower respiratory tract infections. Ideally, the gold standard of care is based on prevention rather than treatment of respiratory infection. However, despite numerous and sometimes imaginative efforts to validate the benefit of these measures, most clinicians now accept that currently available measures have failed to eradicate VAP. Stopping the progression from VAT to VAP could improve patient outcomes.

Frequency and mortality of septic shock in Europe and North America: a systematic review and meta-analysis

Background

Septic shock is the most severe form of sepsis, in which profound underlying abnormalities in circulatory and cellular/metabolic parameters lead to substantially increased mortality. A clear understanding and up-to-date assessment of the burden and epidemiology of septic shock are needed to help guide resource allocation and thus ultimately improve patient care. The aim of this systematic review and meta-analysis was therefore to provide a recent evaluation of the frequency of septic shock in intensive care units (ICUs) and associated ICU and hospital mortality.

Methods

We searched MEDLINE, Embase, and the Cochrane Library from 1 January 2005 to 20 February 2018 for observational studies that reported on the frequency and mortality of septic shock. Four reviewers independently selected studies and extracted data. Disagreements were resolved via consensus. Random effects meta-analyses were performed to estimate pooled frequency of septic shock diagnosed at admission and during the ICU stay and to estimate septic shock mortality in the ICU, hospital, and at 28 or 30 days.

Results

The literature search identified 6291 records of which 71 articles met the inclusion criteria. The frequency of septic shock was estimated at 10.4% (95% CI 5.9 to 16.1%) in studies reporting values for patients diagnosed at ICU admission and at 8.3% (95% CI 6.1 to 10.7%) in studies reporting values for patients diagnosed at any time during the ICU stay. ICU mortality was 37.3% (95% CI 31.5 to 43.5%), hospital mortality 39.0% (95% CI 34.4 to 43.9%), and 28-/30-day mortality 36.7% (95% CI 32.8 to 40.8%). Significant between-study heterogeneity was observed.

Conclusions

Our literature review reaffirms the continued common occurrence of septic shock and estimates a high mortality of around 38%. The high level of heterogeneity observed in this review may be driven by variability in defining and applying the diagnostic criteria, as well as differences in treatment and care across settings and countries.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2478-6) contains supplementary material, which is available to authorized users.

Cirrhotic patients admitted to the ICU for medical reasons: Analysis of 5506 patients admitted to 286 ICUs in 8years

PURPOSE

To describe characteristics and prognostic factors of cirrhotic patients admitted to a representative sample of Italian intensive care units (ICUs).

MATERIALS AND METHODS

All patients admitted to 286 ICUs for medical reasons between 2002 and 2010 (excluding 2007) were considered. A logistic regression model was developed on cirrhotics to predict hospital mortality. The prediction was applied to different subgroups defined by both the level of unit expertise with cirrhotics and the overall unit performance, and compared to the actual mortality.

RESULTS

5506 cirrhotic patients (32.1% admitted to the ICU for non-cirrhotic-related reasons) were compared to 130,477 controls. Hospital mortality was higher in cirrhotics (57.2% vs. 35.0%, p<0.001). ICU volume of cirrhotic patients did not influence mortality, while the overall performance of the unit did. The standardized mortality ratio for overall lower-performing units was 1.09 (95%CI: 1.05-1.14), for the average-performing units it was 1.01 (95%CI: 0.98-1.04), for the higher-performing units it was 0.92 (95%CI: 0.89-0.96).

CONCLUSIONS

The outcome of critically ill cirrhotic patients is quite poor, but not to limit their admission to the ICU. When cirrhosis accompanies other acute conditions, the general level of intensive care medicine is more important than the specific liver-oriented expertise in treating these patients.

Paclitaxel alleviated liver injury of septic mice by alleviating inflammatory response via microRNA-27a/TAB3/NF-κB signaling pathway

Excessive inflammatory response and apoptosis play an important role in the sepsis-induced liver injury. Paclitaxel, a diterpene alkaloid of Taxus brevifolia, is widely used as an anti-tumor drug and shows protective effects on acute lung and kidney injury. However, whether it has a protective effect against sepsis-induced liver injury has not been reported. The objective of this study was to investigate the protective effects of paclitaxel in septic liver injury in mice and associated molecular mechanisms. Our results showed that paclitaxel treatment improved LPS-induced liver injury, as evidenced by the reduced aminotransferase activity, histological scores and apoptosis in the liver tissues. This was accompanied by the alleviating of inflammation and oxidative stress, such as decreased levels of tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-6) interleukin-1β (IL-1β) and malondialdehyde (MDA) and increased levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in serum and liver tissues. Subsequent microarray and qRT-PCR analysis further showed that miR-27a was significantly decreased in mice with sepsis, which was recovered by paclitaxel pretreatment. Antagomir-miR-27a suppressed the therapeutic effects of paclitaxel in mice liver injury model via promoting inflammatory response. Of note, TAB3, which participated in the activation of the NF-κB signaling pathway, was identified as a direct target of miR-27 by luciferase reporter gene assays. Then, we revealed a reverse relationship between miR-27a expression levels and TAB3 mRNA levels in liver tissues from septic mice. Furthermore, paclitaxel treatment significantly decreased the expression of NF-κB p65, but increased inhibitor of nuclear factor-κB-α (IκBα) protein levels in septic mice, suggesting the inactivation of NF-κB signaling pathway. Notably, the inhibitory effects of paclitaxel on NF-κB signaling pathway were reversed by antagomir-miR-27a. Our data indicated that paclitaxel significantly attenuated septic induced liver injury through reducing inflammatory response via miR-27a/TAB3/NF-κB signaling pathway.

Pterostilbene alleviates polymicrobial sepsis-induced liver injury: Possible role of SIRT1 signaling

Liver injury occurs frequently during sepsis. Pterostilbene (Pte), a natural dimethylated analog of resveratrol from blueberries, exerts anti-inflammatory and anti-apoptotic effects in various diseases. However, the role of Pte in sepsis-induced liver injury and its underlying mechanisms remain unknown. The current study aimed to evaluate the protective effects of Pte on sepsis-induced liver injury and its potential mechanisms. Sepsis was induced using cecal ligation and puncture (CLP) in C57BL/6 mice. Mice were administered Pte (5, 10, 15mg/kg, i.p.) at 0.5h, 2h, and 8h after CLP induction. The pathological changes of the liver were evaluated using hematoxylin and eosin (H&E) staining. The serum levels of alanine transaminase (ALT) and aspartate aminotransferase (AST) were measured. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL-6), myeloperoxidase (MPO), p38 mitogen-activated protein kinase (p38MAPK), Bax, and B-cell lymphoma 2 (Bcl-2) were also evaluated. Pte treatment attenuated the CLP-induced liver injury, as evidenced by the attenuated histopathologic injuries and the decreased serum aminotransferase levels. Pte reduced the serum inflammatory cytokine (TNF-α and IL-6) levels and hepatic mRNA levels of TNF-α and IL-6. Pte also reduced MPO activity and p38MAPK activation in the liver. Additionally, Pte significantly inhibited Bax expression and increased Bcl-2 expression. Moreover, Pte increased the expression of sirtuin-1 (SIRT1) and reduced the expression of acetylated forkhead box O1 (Ac-FoxO1), acetylated Ac-p53, and acetylated nuclear factor-kappa beta (Ac-NF-κB). However, SIRT1 small interfering RNA (siRNA) abolished Pte's effects on the expression levels of those protein. Notably, Pte improved the survival rate in septic mice. In conclusion, Pte alleviates sepsis-induced liver injury by reducing inflammatory response and inhibiting hepatic apoptosis, and the potential mechanism is associated with SIRT1 signaling activation.

Pyrexia: aetiology in the ICU

Elevation in core body temperature is one of the most frequently detected abnormal signs in patients admitted to adult ICUs, and is associated with increased mortality in select populations of critically ill patients. The definition of an elevated body temperature varies considerably by population and thermometer, and is commonly defined by a temperature of 38.0 °C or greater. Terms such as hyperthermia, pyrexia, and fever are often used interchangeably. However, strictly speaking hyperthermia refers to the elevation in body temperature that occurs without an increase in the hypothalamic set point, such as in response to specific environmental (e.g., heat stroke), pharmacologic (e.g., neuroleptic malignant syndrome), or endocrine (e.g., thyrotoxicosis) stimuli. On the other hand, pyrexia and fever refer to the classical increase in body temperature that occurs in response to a vast list of infectious and noninfectious aetiologies in association with an increase in the hypothalamic set point. In this review, we examine the contemporary literature investigating the incidence and aetiology of pyrexia and hyperthermia among medical and surgical patients admitted to adult ICUs with or without an acute neurological condition. A temperature greater than 41.0 °C, although occasionally observed among patients with infectious or noninfectious pyrexia, is more commonly observed in patients with hyperthermia. Most episodes of pyrexia are due to infections, but incidence estimates of infectious and noninfectious aetiologies are limited by studies with small sample size and inconsistent reporting of noninfectious aetiologies. Pyrexia commonly triggers a full septic work-up, but on its own is a poor predictor of culture-positivity. In order to improve culturing practices, and better guide the diagnostic approach to critically ill patients with pyrexia, additional research is required to provide more robust estimates of the incidence of infectious and noninfectious aetiologies, and their relationship to other clinical features (e.g., leukocytosis). In the meantime, using existing literature, we propose an approach to identifying the aetiology of pyrexia in critically ill adults.

Sampling and analyzing alveolar exhaled breath condensate in mechanically ventilated patients: a feasibility study

Recent studies in spontaneously breathing subjects indicate the possibility of obtaining the alveolar fraction of exhaled breath condensate (aEBC). In critically ill mechanically ventilated patients, in whom microbial colonization of the upper airways is constant, collection of aEBC could considerably add to the ability of monitoring alveolar inflammation. We designed this study to test the feasibility of collecting aEBC in mechanically ventilated critically ill patients through a dedicated apparatus, i.e. a CO2 valve combined with a condenser placed in the expiratory limb of the ventilator circuit. We also aimed to assess the adequacy of the samples obtained by measuring different markers of oxidative stress and inflammation. We enrolled 40 mechanically ventilated patients, 20 with and 20 without acute respiratory distress syndrome (ARDS). Measurements of respiratory mechanics, gas exchange and hemodynamics were obtained with a standard ventilator circuit after 30 min of aEBC collection and after inserting the dedicated collecting apparatus. Data showed that intrinsic positive end-expiratory pressure, peak and plateau pressure, static compliance and airway resistance (Raw) were similar before and after adding the collecting apparatus in both ARDS and controls. Similarly, gas exchange and hemodynamic variables did not change and 30 min collection provided a median aEBC volume of 2.100 and 2.300 ml for ARDS and controls, respectively. aEBC pH showed a trend toward a slight reduction in the ARDS group of patients, as opposed to controls (7.83 (7.62-8.03) versus 7.98 (7.87-8.12), respectively, p  =  0.055)). H2O2 was higher in patients with ARDS, compared to controls (0.09 (0.06-0.12) μM versus 0.03 (0.01-0.09) μM, p  =  0.043), while no difference was found in proteins content, 8-isoprostane, 4-hydroxy-2-nonhenal. In conclusion, we demonstrate, in patients receiving controlled mechanical ventilation, that aEBC collection is feasible without detrimental effects on ventilator functioning, respiratory mechanics and gas exchange. In addition, we show that the sample obtained is appropriate for compounds analysis.

Incidence and prognosis of ventilator-associated tracheobronchitis (TAVeM): a multicentre, prospective, observational study

BACKGROUND

Ventilator-associated tracheobronchitis has been suggested as an intermediate process between tracheobronchial colonisation and ventilator-associated pneumonia in patients receiving mechanical ventilation. We aimed to establish the incidence and effect of ventilator-associated tracheobronchitis in a large, international patient cohort.

METHODS

We did a multicentre, prospective, observational study in 114 intensive care units (ICU) in Spain, France, Portugal, Brazil, Argentina, Ecuador, Bolivia, and Colombia over a preplanned time of 10 months. All patients older than 18 years admitted to an ICU who received invasive mechanical ventilation for more than 48 h were eligible. We prospectively obtained data for incidence of ventilator-associated lower respiratory tract infections, defined as ventilator-associated tracheobronchitis or ventilator-associated pneumonia. We grouped patients according to the presence or absence of such infections, and obtained data for the effect of appropriate antibiotics on progression of tracheobronchitis to pneumonia. Patients were followed up until death or discharge from hospital. To account for centre effects with a binary outcome, we fitted a generalised estimating equation model with a logit link, exchangeable correlation structure, and non-robust standard errors. This trial is registered with ClinicalTrials.gov, number NCT01791530.

FINDINGS

Between Sept 1, 2013, and July 31, 2014, we obtained data for 2960 eligible patients, of whom 689 (23%) developed ventilator-associated lower respiratory tract infections. The incidence of ventilator-associated tracheobronchitis and that of ventilator-associated pneumonia at baseline were similar (320 [11%; 10·2 of 1000 mechanically ventilated days] vs 369 [12%; 8·8 of 1000 mechanically ventilated days], p=0·48). Of the 320 patients with tracheobronchitis, 250 received appropriate antibiotic treatment and 70 received inappropriate antibiotics. 39 patients with tracheobronchitis progressed to pneumonia; however, the use of appropriate antibiotic therapy for tracheobronchitis was associated with significantly lower progression to pneumonia than was inappropriate treatment (19 [8%] of 250 vs 20 [29%] of 70, p<0·0001; crude odds ratio 0·21 [95% CI 0·11-0·41]). Significantly more patients with ventilator-associated pneumonia died (146 [40%] of 369) than those with tracheobronchitis (93 [29%] of 320) or absence of ventilator-associated lower respiratory tract infections (673 [30%] of 2271, p<0·0001). Median time to discharge from the ICU for survivors was significantly longer in the tracheobronchitis (21 days [IQR 15-34]) and pneumonia (22 [13-36]) groups than in the group with no ventilator-associated lower respiratory tract infections (12 [8-20]; hazard ratio 1·65 [95% CI 1·38-1·97], p<0·0001).

INTERPRETATION

This large database study emphasises that ventilator-associated tracheobronchitis is a major health problem worldwide, associated with high resources consumption in all countries. Our findings also show improved outcomes with use of appropriate antibiotic treatment for both ventilator-associated tracheobronchitis and ventilator-associated pneumonia, underlining the importance of treating both infections, since inappropriate treatment of tracheobronchitis was associated with a higher risk of progression to pneumonia.

FUNDING

None.

Melatonin alleviates brain injury in mice subjected to cecal ligation and puncture via attenuating inflammation, apoptosis, and oxidative stress: the role of SIRT1 signaling

Sepsis is a systemic inflammatory response to infection that causes severe neurological complications. Previous studies have suggested that melatonin is protective during sepsis. Additionally, silent information regulator 1 (SIRT1) was reported to be beneficial in sepsis. However, the role of SIRT1 signaling in the protective effect of melatonin against septic encephalopathy remains unclear. This study aimed to investigate the role of SIRT1 in the protective effect of melatonin. EX527, a SIRT1 inhibitor, was used to reveal the role of SIRT1 in melatonin's action. Cecal ligation and puncture or sham operation was performed in male C57BL/6J mice. Melatonin was administrated intraperitoneally (30 mg/kg). The survival rate of mice was recorded for the 7-day period following the sham or CLP operation. The blood-brain barrier (BBB) integrity, brain water content, levels of inflammatory cytokines (TNF-α, IL-1β, and HMGB1), and the level of oxidative stress (superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA)) and apoptosis were assessed. The expression of SIRT1, Ac-FoxO1, Ac-p53, Ac-NF-κB, Bcl-2, and Bax was detected by Western blot. The results suggested that melatonin improved survival rate, attenuated brain edema and neuronal apoptosis, and preserved BBB integrity. Melatonin decreased the production of TNF-α, IL-1β, and HMGB1. Melatonin increased the activity of SOD and CAT and decreased the MDA production. Additionally, melatonin upregulated the expression of SIRT1 and Bcl-2 and downregulated the expression of Ac-FoxO1, Ac-p53, Ac-NF-κB, and Bax. However, the protective effects of melatonin were abolished by EX527. In conclusion, our results demonstrate that melatonin attenuates sepsis-induced brain injury via SIRT1 signaling activation.

Additional benefit of combined therapy with melatonin and apoptotic adipose-derived mesenchymal stem cell against sepsis-induced kidney injury

This study tested whether combined therapy with melatonin and apoptotic adipose-derived mesenchymal stem cells (A-ADMSCs) offered additional benefit in ameliorating sepsis-induced acute kidney injury. Adult male Sprague-Dawley rats (n = 65) were randomized equally into five groups: Sham controls (SC), sepsis induced by cecal-ligation and puncture (CLP), CLP-melatonin, CLP-A-ADMSC, and CLP-melatonin-A-ADMSC. Circulating TNF-α level at post-CLP 6 hr was highest in CLP and lowest in SC groups, higher in CLP-melatonin than in CLP-A-ADMSC and CLP-melatonin-A-ADMSC groups (all P < 0.001). Immune reactivity as reflected in the number of splenic helper-, cytoxic-, and regulatory-T cells at post-CLP 72 hr exhibited the same pattern as that of circulating TNF-α among all groups (P < 0.001). The histological scoring of kidney injury and the number of F4/80+ and CD14+ cells in kidney were highest in CLP and lowest in SC groups, higher in CLP-melatonin than in CLP-A-ADMSC and CLP-melatonin-A-ADMSC groups, and higher in CLP-A-ADMSC than in CLP-melatonin-A-ADMSC groups (all P < 0.001). Changes in protein expressions of inflammatory (RANTES, TNF-1α, NF-κB, MMP-9, MIP-1, IL-1β), apoptotic (cleaved caspase 3 and PARP, mitochondrial Bax), fibrotic (Smad3, TGF-β) markers, reactive-oxygen-species (NOX-1, NOX-2), and oxidative stress displayed a pattern identical to that of kidney injury score among the five groups (all P < 0.001). Expressions of antioxidants (GR+, GPx+, HO-1, NQO-1+) were lowest in SC group and highest in CLP-melatonin-A-ADMSC group, lower in CLP than in CLP-melatonin and CLP-A-ADMSC groups, and lower in CLP-melatonin- than in CLP-A-ADMSC-tretaed animals (all P < 0.001). In conclusion, combined treatment with melatonin and A-ADMSC was superior to A-ADMSC alone in protecting the kidneys from sepsis-induced injury.

Incidence and diagnosis of ventilator-associated tracheobronchitis in the intensive care unit: an international online survey

Introduction

Several aspects of ventilator-associated tracheobronchitis (VAT)—including diagnostic criteria, overlap with ventilator-associated pneumonia (VAP), and appropriate treatment regimens—remain poorly defined. The objectives of this study were to survey reported practices in the clinical and microbiological diagnosis of VAT and to evaluate perceptions of the impact of VAT on patient outcomes.

Methods

We developed a questionnaire consisting of (a) characteristics of the respondent, the ICU, and hospital; (b) current clinical and microbiological diagnostic approach; (c) empirical antibiotic therapy; and (d) the perception of physicians regarding the clinical impact of VAT and its implications.

Results

A total of 288 ICUs from 16 different countries answered the survey: 147 (51%) from the Latin American (LA) group and 141 (49%) from Spain, Portugal, and France (SPF group). The majority of respondents (n = 228; 79.2%) reported making the diagnosis of VAT based on clinical and microbiological criteria, and 40 (13.9%) by clinical criteria alone. Approximately half (50.3%) of the respondents agreed that patients should receive antibiotics for the treatment of VAT. Out of all respondents, 269 (93.4%) assume that a VAT episode increases ICU length of stay, and this perception is greater in the LA group (97.3%) than in the SPF group (89.4%, P <0.05). Half of the physicians considered that VAT increases the risk of mortality, and this perception is again greater in the LA group (58.5% versus 41.1%, P <0.05).

Conclusions

Given the possible high incidence of VAT and the perception of its importance as a risk factor for VAP and mortality, a large multicenter international prospective study would be helpful to validate a consensual definition of VAT, determine its incidence, and delineate its impact on subsequent VAP occurrence.

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.

Efficacy of coupled plasma filtration adsorption (CPFA) in patients with septic shock: a multicenter randomised controlled clinical trial

OBJECTIVES

Coupled plasma filtration adsorption (CPFA, Bellco, Italy), to remove inflammatory mediators from blood, has been proposed as a novel treatment for septic shock. This multicenter, randomised, non-blinded trial compared CPFA with standard care in the treatment of critically ill patients with septic shock.

DESIGN

Prospective, multicenter, randomised, open-label, two parallel group and superiority clinical trial.

SETTING

18 Italian adult, general, intensive care units (ICUs).

PARTICIPANTS

Of the planned 330 adult patients with septic shock, 192 were randomised to either have CPFA added to the standard care, or not. The external monitoring committee excluded eight ineligible patients who were erroneously included.

INTERVENTIONS

CPFA was to be performed daily for 5 days, lasting at least 10 h/day.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary endpoint was mortality at discharge from the hospital at which the patient last stayed. Secondary endpoints were: 90-day mortality, new organ failures and ICU-free days within 30 days.

RESULTS

There was no statistical difference in hospital mortality (47.3% controls, 45.1% CPFA; p=0.76), nor in secondary endpoints, namely the occurrence of new organ failures (55.9% vs 56.0%; p=0.99) or free-ICU days during the first 30 days (6.8 vs 7.5; p=0.35). The study was terminated on the grounds of futility. Several patients randomised to CPFA were subsequently found to be undertreated. An a priori planned subgroup analysis showed those receiving a CPFA dose >0.18 L/kg/day had a lower mortality compared with controls (OR 0.36, 95% CI 0.13 to 0.99).

CONCLUSIONS

CPFA did not reduce mortality in patients with septic shock, nor did it positively affect other important clinical outcomes. A subgroup analysis suggested that CPFA could reduce mortality, when a high volume of plasma is treated. Owing to the inherent potential biases of such a subgroup analysis, this result can only be viewed as a hypothesis generator and should be confirmed in future studies.

CLINICALTRIALSGOV

NCT00332371; ISRCTN24534559.

Infections acquired in intensive care units: results of national surveillance in Belgium, 1997-2010

BACKGROUND AND AIM

To describe the methodology and output of the Belgian surveillance for infections acquired in intensive care units (ICUs) between 1997 and 2010.

METHODS

Since 1997, ICUs in acute care hospitals in Belgium have been encouraged by federal law to participate in a national multi-centre prospective observational surveillance programme. A protocol and software tool for data collection was developed, and the case definitions and methodology follow those of the European Centre for Disease Prevention and Control.

FINDINGS

For 2010, 18 hospitals provided data on 59 observation quarters, 6478 ICU patients and 52,593 ICU patient-days. The mean incidence rates of ICU-acquired pneumonia and intubation-associated pneumonia were 13 per 1000 patient-days and 12 per 1000 intubation-days, respectively. The mean incidence rates of ICU-acquired bloodstream infections, central vascular catheter (CVC)-associated bloodstream infections and CVC-associated primary bloodstream infections were 3.2 per 1000 patient-days, 2.6 per 1000 catheter-days and 2.3 per 1000 catheter-days, respectively. Between 1997 and 2010, stable trends in ICU-acquired pneumonia and bloodstream infections were observed, together with decreasing trends for intubation-associated pneumonia and CVC-associated bloodstream infections, and a stable trend for CVC-associated primary bloodstream infections.

CONCLUSIONS

In Belgium, national surveillance of ICU-acquired infections allows acute care hospitals to track the incidence of infections at local level, enabling comparison with national and European reference data. Between 1997 and 2010, the incidence of ICU-acquired infections increased and the incidence of device-associated infections decreased.

Epidemiology and antimicrobial resistance among commonly encountered bacteria associated with infections and colonization in intensive care units in a university-affiliated hospital in Shanghai

BACKGROUND/PURPOSE

The aim of this study was to classify intensive care unit (ICU) bacterial strains as either ICU-acquired or ICU-on-admission and to compare their epidemiological and antibiogram characteristics.

METHODS

The study was performed in a 1300-bed university-affiliated hospital from January 1, 2006 to December 31, 2010. Based on the time of ICU admission, ICU isolates were classified as ICU-acquired strains (appearing more than 48 hours after admission) or ICU-on-admission strains (appearing 48 hours or less from admission). The microbiological data before ICU admission, the microbiological data, and susceptibility testing were compared between the ICU-acquired and ICU-on-admission bacterial isolates.

RESULTS

The most common ICU-acquired strains were Acinetobacter baumannii (19.5%), Pseudomonas aeruginosa (15.6%), Stenotrophomonas maltophilia (11.5%), Staphylococcus aureus (10.7%), Enterococcus spp. (10.6%), and Klebsiella pneumoniae (9.7%). There were significant differences between ICU-acquired and ICU-on-admission isolates in the susceptibility rates of Gram-negative bacteria to antibiotics, especially the susceptibility of A. baumannii to imipenem [23.8% (ICU-acquired) vs. 44.4% (ICU-on-admission), p < 0.001] and meropenem (24.1% vs. 37.8%, p < 0.001), and the susceptibility of P. aeruginosa to imipenem (39.3% vs. 76.1%, p < 0.001) and meropenem (58.5% vs. 76.1%, p < 0.05). Furthermore, decreased susceptibility rates of A. baumannii and P. aeruginosa to carbapenems were correlated with an extended ICU stay (p < 0.05).

CONCLUSION

Because of decreasing susceptibility rates of pathogens (especially ICU-acquired strains) and a significant correlation with the length of ICU stay, intensivists should consider a patient's time of ICU admission and previous microbiological data and should distinguish ICU-acquired strains from non-ICU-acquired strains so as to initiate optimized empirical antibiotic therapy against ICU-acquired infections.

Sequential organ failure assessment (SOFA) scores differ between genders in a sepsis cohort: cause or effect?

BACKGROUND

Controversy exists regarding the influence of gender on sepsis events and outcome. Epidemiological data from other countries may not always apply to local circumstances. The aim of this study was to identify gender differences in patient characteristics, treatment, and outcome related to the occurrence of sepsis at admission to the ICU.

METHODS

A prospective observational cohort study on patients admitted to the ICU over a 3-year period fulfilling sepsis criteria during the first 24 hours. Demographic data, APACHE II score, SOFA score, TISS 76, aetiology, length of stay (LOS), mortality rate, and aspects of treatment were collected and then analysed with respect to gender differences.

RESULTS

There were no gender-related differences in mortality or length of stay. Early organ dysfunction assessed as SOFA score at admission was a stronger risk factor for hospital mortality for women than for men. This discrepancy was mainly associated with the coagulation sub-score. CRP levels differed between genders in relation to hospital mortality. Infection from the abdominopelvic region was more common among women, whereas infection from skin or skin structures were more common in men.

CONCLUSION

In this cohort, gender was not associated with increased mortality during a 2-year follow-up period. SOFA score at ICU admission was a stronger risk factor for hospital mortality for women than for men. The discrepancy was mainly related to the coagulation SOFA sub-score. Together with differences in CRP levels this may suggest differences in inflammatory response patterns between genders.

Surveillance: A strategy for improving patient safety in acute and critical care units

Surveillance is a nursing intervention that has been identified as an important strategy in preventing and identifying medical errors and adverse events. The definition of surveillance proposed by the Nursing Intervention Classification is the purposeful and ongoing acquisition, interpretation, and synthesis of patient data for clinical decision making. The term surveillance is often used interchangeably with the term monitoring, yet surveillance differs significantly from monitoring both in purpose and scope. Monitoring is a key activity in the surveillance process, but monitoring alone is insufficient for conducting effective surveillance. Much of the attention in the bedside patient safety movement has been focused on efforts to implement processes that ultimately improve the surveillance process. These include checklists, interdisciplinary rounds, clinical information systems, and clinical decision support systems. To identify optimal surveillance patterns and to develop and test technologies that assist critical care nurses in performing effective surveillance, more research is needed, particularly with innovative approaches to describe and evaluate the best surveillance practices of bedside nurses.

Inhaled antibiotic therapy for ventilator-associated tracheobronchitis and ventilator-associated pneumonia: an update

Ventilator-associated pneumonia (VAP) remains a leading cause of morbidity and mortality in mechanically-ventilated patients in the Intensive Care Unit (ICU). Ventilator-associated tracheobronchitis (VAT) was previously believed to be an intermediate stage between colonization of the lower respiratory tract and VAP. More recent data, however, suggest that VAT may be a separate entity that increases morbidity and mortality, independently of the occurrence of VAP. Some, but not all, patients with VAT progress to develop VAP. Although inhaled antibiotics alone could be effective for the treatment of VAP, the current consensus of opinion favors their role as adjuncts to systemic antimicrobial therapy for VAP. Inhaled antibiotics are increasingly employed for salvage therapy in patients with VAP due to multi-drug resistant Gram-negative bacteria. In contrast to VAP, VAT could be effectively treated with inhaled antibiotic therapy alone or in combination with systemic antimicrobials.

Infections of respiratory or abdominal origin in ICU patients: what are the differences?

INTRODUCTION

There are few data related to the effects of different sources of infection on outcome. We used the Sepsis Occurrence in Acutely ill Patients (SOAP) database to investigate differences in the impact of respiratory tract and abdominal sites of infection on organ failure and survival.

METHODS

The SOAP study was a cohort, multicenter, observational study which included data from all adult patients admitted to one of 198 participating intensive care units (ICUs) from 24 European countries during the study period. In this substudy, patients were divided into two groups depending on whether, on admission, they had abdominal infection but no respiratory infection or respiratory infection but no abdominal infection. The two groups were compared with respect to patient and infection-related characteristics, organ failure patterns, and outcomes.

RESULTS

Of the 3,147 patients in the SOAP database, 777 (25%) patients had sepsis on ICU admission; 162 (21%) had abdominal infection without concurrent respiratory infection and 380 (49%) had respiratory infection without concurrent abdominal infection. Age, sex, and severity scores were similar in the two groups. On admission, septic shock was more common in patients with abdominal infection (40.1% vs. 29.5%, P = 0.016) who were also more likely to have early coagulation failure (17.3% vs. 9.5%, P = 0.01) and acute renal failure (38.3% vs. 29.5%, P = 0.045). In contrast, patients with respiratory infection were more likely to have early neurological failure (30.5% vs. 9.9%, P < 0.001). The median length of ICU stay was the same in the two groups, but the median length of hospital stay was longer in patients with abdominal than in those with respiratory infection (27 vs. 20 days, P = 0.02). ICU (29%) and hospital (38%) mortality rates were identical in the two groups.

CONCLUSIONS

There are important differences in patient profiles related to the site of infection; however, mortality rates in these two groups of patients are identical.

Intensive Care Unit-acquired infection as a side effect of sedation

Introduction

Sedative and analgesic medications are routinely used in mechanically ventilated patients. The aim of this review is to discus epidemiologic data that suggest a relationship between infection and sedation, to review available data for the potential causes and pathophysiology of this relationship, and to identify potential preventive measures.

Methods

Data for this review were identified through searches of PubMed, and from bibliographies of relevant articles.

Results

Several epidemiologic studies suggested a link between sedation and ICU-acquired infection. Prolongation of exposure to risk factors for infection, microaspiration, gastrointestinal motility disturbances, microcirculatory effects are main mechanisms by which sedation may favour infection in critically ill patients. Furthermore, experimental evidence coming from studies both in humans and animals suggest that sedatives and analgesics present immunomodulatory properties that might alter the immunologic response to exogenous stimuli. Clinical studies comparing different sedative agents do not provide evidence to recommend the use of a particular agent to reduce ICU-acquired infection rate. However, sedation strategies aiming to reduce the duration of mechanical ventilation, such as daily interruption of sedatives or nursing-implementing sedation protocol, should be promoted. In addition, the use of short acting opioids, propofol, and dexmedetomidine is associated with shorter duration of mechanical ventilation and ICU stay, and might be helpful in reducing ICU-acquired infection rates.

Conclusions

Prolongation of exposure to risk factors for infection, microaspiration, gastrointestinal motility disturbances, microcirculatory effects, and immunomodulatory effects are main mechanisms by which sedation may favour infection in critically ill patients. Future studies should compare the effect of different sedative agents, and the impact of progressive opioid discontinuation compared with abrupt discontinuation on ICU-acquired infection rates.

Device-associated infections in the intensive care units of Cyprus: results of the first national incidence study

BACKGROUND

Surveillance of healthcare-associated infections (HCAIs) has become an integral part of infection control programs in several countries, especially in the intensive care unit (ICU) setting. In contrast, surveillance data on the epidemiology of ICU-acquired infections in Cyprus are limited. The aim of this study was to assess the risk of ICU-acquired infections and to identify areas for improvement in Cypriot hospitals by comparing observed incidence rates with international benchmarks and by specifying the microbiological and antibiotic resistance profiles of infecting organisms.

MATERIALS AND METHODS

An active surveillance protocol was introduced in the ICUs of the four major public hospitals in Cyprus, based on the methodology of the US National Nosocomial Infections Surveillance system.

RESULTS

During February to December 2007, 2,692 patients who were hospitalized in ICUs for a mean length of stay of 5 days acquired 214 infections for an overall incidence rate of 15.8 infections per 1,000 patient-days [95% confidence interval (CI): 13.8-18.1]. Bloodstream infections, pneumonias and urinary tract infections accounted for 80.4% of all infections; of these, 87.8% were device-related. Central line-associated bloodstream infection (CL-BSI) posed the greatest risk (18.6 cases per 1,000 central line-days; 95% CI 14.9-22.9), followed by ventilator-associated pneumonia (VAP) (6.4 cases per 1,000 ventilator-days; 95% CI 4.5-8.8) and catheter-associated urinary tract infection (2.8 cases per 1,000 urinary catheter-days; 95% CI 1.9-4.1). Most frequently isolated pathogens included Pseudomonas aeruginosa (21.6% of all isolates), coagulase-negative Staphylococcus (11.7%), Enterococcus spp. (11.3%) and Staphylococcus aureus (9.2%). Overall, 29.8% of P. aeruginosa isolates were imipenem-resistant and 68.2% of S. aureus were methicillin-resistant. The crude excess mortality rate associated with ICU-acquired infections was 33.2% (95% CI 24.9-41.9%) and the mean post-infection stay in the ICUs was 21.6 days (95% CI 17.0-26.2).

CONCLUSION

In comparison to international benchmarks, the markedly high rate of CL-BSI, the high rate of VAP and the resistance patterns of major infecting pathogens identified in this study emphasize the need to improve current practices for appropriate use and management of invasive devices in Cypriot ICUs.

Fever in the critically ill medical patient

Fever, commonly defined by a temperature of >or=38.3 degrees C (101 degrees F), occurs in approximately one half of patients admitted to intensive care units. Fever may be attributed to both infectious and noninfectious causes, and its development in critically ill adult medical patients is associated with an increased risk for death. Although it is widespread and clinically accepted practice to therapeutically lower temperature in patients with hyperthermic syndromes, patients with marked hyperpyrexia, and selected populations such as those with neurologic impairment, it is controversial whether most medical patients with moderate degrees of fever should be treated with antipyretic or direct cooling therapies. Although treatment of fever may improve patient comfort and reduce metabolic demand, fever is a normal adaptive response to infection and its suppression is potentially harmful. Clinical trials specifically comparing fever management strategies in neurologically intact critically ill medical patients are needed.

Remifentanil discontinuation and subsequent intensive care unit-acquired infection: a cohort study

INTRODUCTION

Recent animal studies demonstrated immunosuppressive effects of opioid withdrawal resulting in a higher risk of infection. The aim of this study was to determine the impact of remifentanil discontinuation on intensive care unit (ICU)-acquired infection.

METHODS

This was a prospective observational cohort study performed in a 30-bed medical and surgical university ICU, during a one-year period. All patients hospitalised in the ICU for more than 48 hours were eligible. Sedation was based on a written protocol including remifentanil with or without midazolam. Ramsay score was used to evaluate consciousness. The bedside nurse adjusted sedative infusion to obtain the target Ramsay score. Univariate and multivariate analyses were performed to determine risk factors for ICU-acquired infection.

RESULTS

Five hundred and eighty-seven consecutive patients were included in the study. A microbiologically confirmed ICU-acquired infection was diagnosed in 233 (39%) patients. Incidence rate of ICU-acquired infection was 38 per 1000 ICU-days. Ventilator-associated pneumonia was the most frequently diagnosed ICU-acquired infection (23% of study patients). Pseudomonas aeruginosa was the most frequently isolated microorganism (30%). Multivariate analysis identified remifentanil discontinuation (odds ratio (OR) = 2.53, 95% confidence interval (CI) = 1.28 to 4.99, P = 0.007), simplified acute physiology score II at ICU admission (1.01 per point, 95% CI = 1 to 1.03, P = 0.011), mechanical ventilation (4.49, 95% CI = 1.52 to 13.2, P = 0.006), tracheostomy (2.25, 95% CI = 1.13 to 4.48, P = 0.021), central venous catheter (2.9, 95% CI = 1.08 to 7.74, P = 0.033) and length of hospital stay (1.05 per day, 95% CI = 1.03 to 1.08, P < 0.001) as independent risk factors for ICU-acquired infection.

CONCLUSIONS

Remifentanil discontinuation is independently associated with ICU-acquired infection.