Ventilator-associated pneumonia

The Efficacy and Safety of Intravenous Colistin Plus Aerosolized Colistin Versus Intravenous Colistin Alone in Critically Ill Trauma Patients With Multi-Drug Resistant Gram-Negative Bacilli Infection

BACKGROUND AND AIM

Gram-negative bacteria (GNB) with potential multiple drug resistance (MDR) have emerged as a major group of organisms causing ventilator-associated pneumonia (VAP). Higher concentrations are deposited directly in the lungs when antibiotics are given via inhalation, minimizing systemic side effects. This study aims to compare the efficacy and safety of intravenous plus aerosolized colistin versus intravenous (IV) colistin alone in critically ill trauma patients who reported MDR-GNB infection on endotracheal aspirate culture.

METHODS

A hundred patients were recruited in the Intensive Care Unit, Trauma Centre, Institute of Medical Sciences, Banaras Hindu University, Varanasi, and randomly assigned to the control (n=50) group, which received IV colistin plus aerosolized colistin and the intervention group (n = 50), which received IV colistin alone. Changes in total leucocyte count (TLC), renal function test (RFT), endotracheal aspirate culture, 24-hour urine output, length of ICU stay, and 28-day ICU mortality were investigated.

RESULTS

Patients receiving intravenous plus nebulized colistin therapy had a better outcome compared to IV colistin alone in terms of faster eradication of MDR-GNB infection. A rise in serum urea and creatinine levels was seen in both groups, which were significantly higher, along with a decrease in urine output in the group receiving intravenous colistin alone. No significant difference was observed in serum sodium and potassium levels in the RFT protocol, length of ICU stay, or 28-day ICU mortality.

CONCLUSION

Intravenous nebulized colistin could be considered a better alternative therapy for VAP caused by multi-drug-resistant Gram-negative bacteria in the ICU in terms of faster microbiological cure and lesser nephrotoxicity.

Oral Care Associated With Less Microaspiration in Ventilated Cardiac Patients

Aspiration is common in mechanically ventilated patients and may predispose patients to aspiration pneumonia, chemical pneumonitis, and chronic lung damage. Pepsin A is a specific marker of gastric fluid aspiration and is often detected in ventilated pediatric patients. We investigated the effect of oral care and throat suctioning in the detection of pepsin A in tracheal aspirates (TAs) up to 4 hours after these procedures.

Methods

Twelve pediatric patients between age 2 weeks to 14 years who underwent intubation for cardiac surgery were enrolled in this study. Six of the 12 patients were consented before their surgery with initial specimen collected at the time of intubation and last one shortly before extubation (intubation duration < 24 hours). The remaining 6 patients were consented after cardiac surgery. All specimens were collected per routine care per respiratory therapy protocol and shortly before extubation (intubation duration > 24 hours). Tracheal fluid aspirates were collected every 4 to 12 hours in the ventilated patients. Enzymatic assay for gastric pepsin A and protein determination were performed. The time of oral care and throat suctioning within 4 hours prior was recorded prospectively.

Results

A total of 342 TA specimens were obtained from the 12 intubated pediatric patients during their course of hospitalization; 287 (83.9%) showed detectable total pepsin (pepsin A and C) enzyme activity (> 6 ng/mL) and 176 (51.5%) samples had detectable pepsin A enzyme levels (>6 ng/mL of pepsin A). Only 29 samples of 76 samples (38.2%) had evidence of microaspiration after receiving oral care, while 147 of 266 (55.3%) samples were pepsin A positive when no oral care was provided. Odds ratio is 0.50 (Cl 0.30-0.84), and the number needed to treat is 5.8 (Confidence interval 3.4-22.3). Testing air filters for pepsin was not beneficial.

Conclusion

Oral care is a highly effective measure to prevent microaspiration of gastric fluid in ventilated pediatric patients. The number needed to treat (5.8) suggests this is a very effective prevention strategy. Our study suggests that pepsin A is a useful and sensitive biomarker that allows identification of gastric aspiration.

A functional polymorphism at the miR‑491‑5p binding site in the 3'‑untranslated region of the MMP‑9 gene increases the risk of developing ventilator‑associated pneumonia

Matrix metalloproteinase (MMP)‑9 is associated with the severity of ventilator‑associated pneumonia (VAP), while an rs1056629 SNP located in the 3'‑untranslated region (UTR) of MMP‑9 affects the microRNA (miRNA/miR)‑491‑mediated regulation of MMP‑9 expression. In the present study, the effect of rs1056629 on the development of VAP in patients with chronic obstructive pulmonary disease (COPD) was investigated. Patients with COPD were enrolled in the study and their genotypes of rs1056629 (CC, CA or AA) were determined. ELISA was used to analyze the levels of TNF‑α and IL‑6 in the monocytes of patients with COPD carrying differential genotypes of rs1056629. Reverse transcription‑quantitative PCR was carried out to evaluate the expression of miR‑491 and MMP‑9 mRNA in the different groups of patients with COPD. Luciferase assay was used to confirm the inhibitory role of miR‑491 in MMP‑9 expression. Western blot analysis was carried out to assess the expression of MMP‑9 protein in A549 and H1299 cells transfected with miR‑491 mimics. The risk and severity of VAP were significantly elevated in patients with COPD carrying the CC and AC genotypes of rs1056629. Although there was no difference in the expression of miR‑491 in patients carrying different genotypes of rs1056629, the expression levels of TNF‑α, IL‑6 and MMP‑9 were increased in patients with COPD carrying the CC and AC genotypes of rs1056629. The results of luciferase assay revealed that miR‑491 inhibited the expression of MMP‑9 through direct binding to the 3'UTR of MMP‑9. Transfection of miR‑491 mimics into A549 and H1299 cells markedly suppressed the expression of MMP‑9 in a concentration‑dependent manner. On the whole, the findings of the present study confirm that the CC and AC genotypes of rs1056629 increase the risk of developing VAP in patients with COPD by increasing the expression of MMP‑9.

Distribution and drug resistance of pathogenic bacteria in ventilator-associated pneumonia at a local hospital of North-eastern China

Purpose

To study the distribution of pathogenic bacteria in ventilator-associated pneumonia (VAP), and epidemiological characteristics of extended-spectrum β lactamase (ESBL)-producing bacteria.

Patients and methods

Lower respiratory tract secretions from 156 patients with mechanical ventilation were collected using a protective specimen brush (PSB), with quantitative bacterial culture carried out and antibiotic sensitivity measured. ESBLs produced by Gram-negative bacilli were detected using the double disk diffusion method and monitored by plasmid profiles.

Results

Gram-negative bacilli accounted for 78.9% of VAP pathogens, with Acinetobacter baumannii (25%), Pseudomonas aeruginosa (19.7%), and Klebsiella pneumoniae (14.5%) as the most common strains. There were 12 Gram-positive strains detected (15.8%); mostly methicillin-resistant. Staphylococcus aureus and methicillin-resistant coagulase-negative Staphylococcus. There were also four strains of Candida albicans detected (5.26%). Most Gram-negative bacilli are sensitive to imipenem, but A. baumannii is serious resistant. ESBLs were detected in nine strains of Gram-negative bacilli; mainly produced by K. pneumoniae and Escherichia coli, to different degrees of multidrug resistance. Five strains of K. pneumoniae-producing ESBLs were from the same clonal origin, as confirmed by plasmid restriction endonuclease analysis.

Conclusion

VAP was mainly caused by Gram-negative bacteria, with high antibiotic resistance rates. Plasmids played an important role in the spread of antibiotic resistance among bacteria.

Can probiotics be an alternative to chlorhexidine for oral care in the mechanically ventilated patient? A multicentre, prospective, randomised controlled open trial

Background

Pathogenic enteric bacteria aspirated from the oropharynx are the main cause of ventilator-associated pneumonia (VAP). Using chlorhexidine (CHX) orally or selective decontamination has been shown to reduce VAP. In a pilot study we found that oral care with the probiotic bacterium Lactobacillus plantarum 299 (Lp299) was as effective as CHX in reducing enteric bacteria in the oropharynx. To confirm those results, in this expanded study with an identical protocol we increased the number of patients and participating centres.

Methods

One hundred and fifty critically ill patients on mechanical ventilation were randomised to oral care with either standard 0.1% CHX solution (control group) or a procedure comprising final application of an emulsion of Lp299. Samples for microbiological analyses were taken from the oropharynx and trachea at inclusion and subsequently at defined intervals.

Student’s t test was used for comparisons of parameters recorded daily and Fisher’s exact test was used to compare the results of microbiological cultures.

Results

Potentially pathogenic enteric bacteria not present at inclusion were identified in oropharyngeal samples from 29 patients in the CHX group and in 31 samples in the probiotic group. Considering cultures of tracheal secretions, enteric bacteria were found in 17 and 19 samples, respectively. Risk ratios show a difference in favour of the Lp group for fungi in oropharyngeal cultures. VAP was diagnosed in seven patients in the Lp group and in 10 patients among the controls.

Conclusions

In this multicentre study, we could not demonstrate any difference between Lp299 and CHX used in oral care procedures regarding their impact on colonisation with emerging potentially pathogenic enteric bacteria in the oropharynx and trachea.

Trial registration

ClinicalTrials.gov, NCT01105819. Registered on 9 April 2010.

First part: Current Controlled Trials, ISRCTN00472141. Registered on 22 November 2007 (published Critical Care 2008, 12:R136).

Hypertension, mitral valve disease, atrial fibrillation and low education level predict delirium and worst outcome after cardiac surgery in older adults

Background

Delirium is a common complication after cardiac surgery in older adult patients. However, risk factors and the influence of delirium on patient outcomes are not well established. We aimed to determine the incidence, predisposing and triggering factors of delirium following cardiac surgery.

Methods

One hundred seventy-three consecutive patients aged ≥60 years were studied. Patients’ characteristics and two cognitive function assessment tests were recorded preoperatively. Perioperative variables were blood transfusion, orotracheal intubation time (OIT), renal dysfunction, and hypoxemia. Delirium was assessed using the Confusion Assessment Method for the Intensive Care Unit. The composite outcome consisted of death, infection, and perioperative myocardial infarction until hospital discharge or 30 days after surgery, and for up to 18 months.

Results

One hundred six patients (61.27%) were men and the age was 69.5 ± 5.8 years. EuroSCORE II index was 4.06 ± 3.86. Hypertension was present in 75.14%, diabetes in 39.88%, and 30.06% were illiterate. Delirium occurred in 59 patients (34.1%). Education level (OR 0.81, 0.71–0.92), hypertension (OR 2.73, 1.16–6.40), and mitral valve disease (OR 2.93, 1.32–6.50) were independent predisposing factors for delirium, and atrial fibrillation after surgery (OR 2.49, 1.20–5.20) represented the potential triggering factor. Delirium (OR 2.35, 1.20–4.58) and OIT ≥ 900 min (OR 2.50; 1.30–4.80) were independently associated with the composite outcome.

Conclusions

In older adult patients submitted to cardiac surgery, delirium is a frequent complication that is associated with worst outcome. Independent risk factors for delirium included education level, hypertension, mitral valve disease, and atrial fibrillation after cardiac surgery.

Emerging trends of nosocomial pneumonia in intensive care unit of a tertiary care public teaching hospital in Western India

BACKGROUND

Nosocomial pneumonia poses great challenge to an intensivist. Detailed information about hospital-acquired pneumonia (HAP) and ventilator-acquired pneumonia (VAP) is crucial for prevention and optimal management, thus improving quality Intensive Care Unit (ICU) care. Hence, we aimed to study the current trend of nosocomial pneumonia in ICU.

MATERIALS AND METHODS

It was a prospective observational cohort study, conducted in the ICU of a tertiary care teaching public hospital over a period of 18 months. We studied clinical profile and outcome of 120 adult patients who developed VAP/HAP during the study period. We also analyzed the causative organisms, antibiotic sensitivity, and resistance pattern in these patients.

RESULTS

Out of 120 patients, 29 patients were HAP and 91 patients were VAP. Mortality was 60% (72), and development of VAP and requirement of mechanical ventilation showed significant association with mortality (P < 0.00001). Most common organism causing HAP was Staphylococcus aureus (43.4%) and VAP was Klebsiella pneumoniae (49%). Maximum antibiotic sensitivity was found to piperacillin + tazobactam (58.8%), followed by imipenem (49.5%) and meropenem (41.8%), whereas maximum antibiotic resistance was found to cefepime (95.1%), followed by ceftazidime and amoxicillin (91.2%).

CONCLUSION

Nosocomial pneumonia showed high incidence (17.44%) and mortality (60%). Common organisms identified were S. aureus and K. pneumoniae. Resistance was high for commonly used antibiotics and high antibiotic sensitivity for piperacillin + tazobactam and carbapenem. Contexte: La pneumonie nosocomiale pose un grand défi à un intensiviste. Des informations détaillées sur la pneumonie acquise dans les hôpitaux (HAP) et la pneumonie acquise par le ventilateur (VAP) sont essentielles pour la prévention et la gestion optimale, améliorant ainsi les soins de soins intensifs de qualité (UTI). Par conséquent, nous avons cherché à étudier la tendance actuelle de la pneumonie nosocomiale en UTI. Matériaux et méthodes: il s'agissait d'une étude de cohorte observationnelle prospective menée dans l'UCI d'un hôpital public d'enseignement tertiaire sur une période de 18 mois. Nous avons étudié le profil clinique et le résultat de 120 patients adultes qui ont développé le VAP / HAP pendant la période d'étude. Nous avons également analysé les organismes responsables, la sensibilité aux antibiotiques et le modèle de résistance chez ces patients. Résultats: Sur 120 patients, 29 patients étaient HAP et 91 patients étaient VAP. La mortalité était de 60% (72), et le développement du VAP et l'exigence de ventilation mécanique ont montré une association significative avec la mortalité (P < 0,00001). L'organisme le plus fréquent causant HAP était Staphylococcus aureus (43,4%) et VAP était Klebsiella pneumoniae (49%). Une sensibilité antibiotique maximale a été observée chez la pipéracilline + tazobactam (58,8%), suivie de l'imipénème (49,5%) et du méropénem (41,8%), alors que la résistance antibiotique maximale a été observée à cefépime (95,1%), suivie de ceftazidime et de l'amoxicilline (91,2%) .

CONCLUSION

la pneumonie nosocomiale a montré une incidence élevée (17,44%) et la mortalité (60%). Les organismes communs identifiés étaient S. aureus et K. pneumoniae. La résistance était élevée pour les antibiotiques couramment utilisés et une forte sensibilité aux antibiotiques pour la pipéracilline + le tazobactam et le carbapénème.

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.

Hospital-Acquired Pneumonia in the Intensive Care Units of Polish Hospitals

We analyzed the epidemiological characteristics of pneumonia in intensive care units of Polish hospitals. Among 11,587 patients, there were 191 cases of hospital-acquired pneumonia (HAP). The incidence of HAP was 5.6%, and that of ventilator-associated pneumonia (VAP) was 17.9%. The overall mortality rate was 12.6%, and the mortality rate for patients who received artificial ventilation was 15.0%. The predominant organisms causing HAP and VAP were Pseudomonas aeruginosa and Escherichia coli, and 21.1% of Staphylococcus aureus isolates were resistant to methicillin.

The Effect of a Designed Respiratory Care Program on the Incidence of Ventilator-Associated Pneumonia: A Clinical Trial

INTRODUCTION

Ventilator-associated pneumonia is a common complication of mechanical ventilation. This study aimed to evaluate the effect of designed respiratory care program on incidence of ventilator-associated pneumonia (VAP) in the mechanically ventilated patient.

METHODS

In this clinical trial, 64 patients were selected among those who had undergone mechanical ventilation in the ICU of Al‑Zahra Hospital, Isfahan, Iran, using convenience sampling method. The subjects were randomly allocated to intervention and control groups. In the intervention group an upper respiratory care program and in the control group, routine cares were done. Modified Clinical Pulmonary Infection Questionnaire was completed before and on the third, fourth and fifth day of study. Data were analyzed by Chi-square and independent t-test through SPSS Ver.13.

RESULTS

The results of this study showed that until the third day of study, the incidence of VAP was similar in the both groups. However, on the fifth day of study, the incidence of VAP in the intervention group was significantly lower than control group.

CONCLUSION

The results of this study showed that an upper respiratory care program reduced the incidence of VAP. Therefore, nurses are recommended to perform this program for prevention of VAP.

Association of autophagy-related 16-like 1 (ATG16L1) gene polymorphism with sepsis severity in patients with sepsis and ventilator-associated pneumonia

Autophagy is a highly conserved mechanism of eukaryotic cells implicated in cell homeostasis and elimination of intracellular pathogens. Functional polymorphisms in genes encoding for autophagy have been associated with susceptibility to inflammatory and infectious diseases, but data on severe infections are missing. The aim of the present study was to assess whether polymorphisms in genes encoding proteins involved in autophagy influence susceptibility to ventilator-associated pneumonia (VAP). Mechanically ventilated patients with VAP were studied. Genotyping for autophagy-related 16-like 1 (ATG16L1, rs2241880) functional polymorphism was performed using the TaqMan single-nucleotide assay. Monocytes were isolated from patients and stimulated with lipopolysaccharide (LPS). Tumor necrosis factor-α (TNF-α) was measured in the supernatants of monocytes using an enzyme-linked immunosorbent assay. Procalcitonin (PCT) was also measured in the serum of patients by an immuno-time-resolved amplified cryptate technology assay. A total of 155 patients with VAP were enrolled in the study. Carriage of the minor A allele of ATG16L1 was associated with septic shock with at least one organ failure (odds ratio (OR): 2.40, p: 0.036). TNF-α production was significantly greater among the carriers of the polymorphism presenting with at least one organ failure (p: 0.040). PCT was increased upon worsening to septic shock and organ failure only among carriers of the minor frequency A alleles. In a homogeneous cohort of septic patients with VAP, the carriage of autophagy polymorphisms predisposes to VAP severity and septic shock development. This may be related with predisposition to immunoparalysis.

The role of procalcitonin and IL-6 in discriminating between septic and non-septic causes of ALI/ARDS: a prospective observational study

BACKGROUND

The aim was to evaluate the clinical usefulness of a single plasma and bronchoalveolar lavage fluid (BALF) PCT and IL-6 measurement in discriminating septic from non-septic causes of acute respiratory distress syndrome (ARDS) and forecasting clinical outcomes.

METHODS

One hundred patients were enrolled within 48 h of ALI/ARDS recognition. Demographic, clinical data, severity indices were recorded and PCT and IL-6 concentrations were measured in plasma and BALF.

RESULTS

Plasma PCT and IL-6 values were significantly higher in septic compared to non-septic individuals (p=0.001 and 0.0005, respectively), while there were no differences in their respective BALF values. As far as identification of septic vs. non-septic ARDS is concerned, the comparison of the areas under the curves favored PCT vs. IL-6 [0.88, (95% CI 0.81-0.95) vs. 0.71, (95% CI 0.60-0.81); χ(2)=9.04, p=0.003]. A plasma PCT level of 0.815 ng/mL was associated with 74.1% sensitivity and 97.6% specificity in identifying septic ARDS cases; this corresponded to a diagnostic odds ratio value of 116. Linear regression multivariable analysis disclosed a significant relation of plasma PCT with SOFA score in septic ARDS patients (p<0.001), while neither BALF PCT nor IL-6 levels were associated with clinical outcome.

CONCLUSIONS

Early plasma - but not BALF - PCT concentrations can discriminate between septic and non-septic ARDS causes and are associated with the severity of multiple organ dysfunction syndrome in septic ARDS patients. However, neither plasma or BALF IL-6 levels nor BALF PCT levels carry any prognostic potential. A single plasma PCT value higher than 0.815 ng/mL makes a non-septic cause of ARDS highly unlikely.

Genetic polymorphisms within tumor necrosis factor gene promoter region: a role for susceptibility to ventilator-associated pneumonia

Debatable findings exist among various studies regarding the impact of single nucleotide polymorphisms (SNPs) within the promoter region of the tumor necrosis factor (TNF) gene for susceptibility to infections. Their impact was investigated in a cohort of mechanically ventilated patients who developed ventilator-associated pneumonia (VAP). Two-hundred and thirteen mechanically ventilated patients who developed VAP were enrolled. Genomic DNA was extracted and SNPs at the -376, -308 and -238 position of the promoter region of the TNF gene were assessed by restriction fragment length polymorphisms. Monocytes were isolated from 47 patients when they developed sepsis and stimulated by bacterial endotoxin for the production of TNFα and of interleukin-6 (IL-6). Patients were divided into two groups; 166 patients bearing only wild-type alleles of all three studied polymorphisms; and 47 patients carrying at least one A allele of the three studied SNPs. Time between start of mechanical ventilation and advent of VAP was significantly shorter in the second group than in the first group (log-rank: 4.416, p: 0.041). When VAP supervened, disease severity did not differ between groups. Stimulation of TNFα and of IL-6 was much greater by monocytes for patients carrying A alleles. Carriage of at least one A allele of the three studied SNPs at the promoter region of the TNF-gene is associated with shorter time to development of VAP but it is not associated with disease severity. Findings may be related with a role of the studied SNPs in the production of pro-inflammatory cytokines.

Ventilator-associated pneumonia: a review

Ventilator-associated pneumonia (VAP) is the most common infection seen in intensive care units (ICUs); it accounts for one-fourth of the infections occurring in critically ill patients and is the reason for half of antibiotic prescriptions in mechanically ventilated patients. In addition to being a financial burden on ICUs, it continues to contribute significantly to the morbidity and mortality of ICU patients, with an estimated attributable mortality rate of 8% to 15%. While the pathophysiology of VAP remains relatively unchanged, diagnostic techniques and preventive measures are constantly evolving. The focus of this article is on recent trends in VAP epidemiology, modifiable risk factors, diagnostic techniques, challenges in management, and current data on the prevention of VAP. Important messages that the reader should take away include: 1) There is no gold standard for the diagnosis of VAP; whenever VAP is suspected, if feasible, a quantitative culture should be obtained by invasive or noninvasive methods (whichever is more readily available before initiation of antibiotics); 2) Suspicion based on clinical features should prompt the initiation of a broad spectrum of antibiotics depending on suspected pathogens; 3) Close attention should be paid to de-escalation of antibiotics once microbiological results become available or as the patient starts responding clinically; the ideal duration of treatment should be 8 days instead of the conventional 10 to 14 days, except in situations where Pseudomonas may be suspected or the patient's comorbidities dictate otherwise; and 4) Prevention remains the key to reducing the burden of VAP. We promote the proven preventive measures of using noninvasive ventilation when possible, semirecumbent patient positioning, continuous aspiration of subglottic secretions, and oral chlorhexidine washes along with stress ulcer prophylaxis only after careful assessment of the risks versus benefits.

Pathogens in the lower respiratory tract of intensive care unit patients: impact of duration of hospital care and mechanical ventilation

BACKGROUND

Ventilator-associated pneumonia (VAP), the most common hospital-acquired infection in intensive care unit (ICU) patients, is caused by bacteria in the lower respiratory tract of mechanically ventilated patients.

METHODS

The current study was focused on 443 bacterial isolates from the lower respiratory tract of mechanically ventilated ICU patients (n = 346) in a Swedish University Hospital. Data were obtained from a prospective infection control database covering 9 y (2002-2010). We analysed the correlation between duration of hospital care and mechanical ventilation at the time of sampling on the occurrence of different pathogens.

RESULTS

Duration of hospital care and mechanical ventilation prior to sampling was similarly short for Streptococcus pneumoniae, beta-streptococci, and Haemophilus influenzae (≤ 2 days). In contrast, duration of hospital care and mechanical ventilation were longest for Stenotrophomonas maltophilia (6 and 11 days). For Staphylococcus aureus, the most common Gram-positive isolate, the duration was longer than for S. pneumoniae but shorter than for most Gram-negative bacteria. With the exception of S. maltophilia and Pseudomonas aeruginosa, the median duration of mechanical ventilation was short and similar for most bacteria. In samples taken on the first day of mechanical ventilation, the rate of pathogens expected to be resistant to cefotaxime was 23%.

CONCLUSIONS

The occurrence of pathogens with high antibiotic resistance in the lower respiratory tract increases with increased duration of hospital care and mechanical ventilation. An equally important result is that pathogens resistant to third-generation cephalosporins were more common than expected, even after a very short duration of hospital care and mechanical ventilation.

TREM-1 expression on neutrophils and monocytes of septic patients: relation to the underlying infection and the implicated pathogen

BACKGROUND

Current knowledge on the exact ligand causing expression of TREM-1 on neutrophils and monocytes is limited. The present study aimed at the role of underlying infection and of the causative pathogen in the expression of TREM-1 in sepsis.

METHODS

Peripheral venous blood was sampled from 125 patients with sepsis and 88 with severe sepsis/septic shock. The causative pathogen was isolated in 91 patients. Patients were suffering from acute pyelonephritis, community-acquired pneumonia (CAP), intra-abdominal infections (IAIs), primary bacteremia and ventilator-associated pneumonia or hospital-acquired pneumonia (VAP/HAP). Blood monocytes and neutrophils were isolated. Flow cytometry was used to estimate the TREM-1 expression from septic patients.

RESULTS

Within patients bearing intrabdominal infections, expression of TREM-1 was significantly lower on neutrophils and on monocytes at severe sepsis/shock than at sepsis. That was also the case for severe sepsis/shock developed in the field of VAP/HAP. Among patients who suffered infections by Gram-negative community-acquired pathogens or among patients who suffered polymicrobial infections, expression of TREM-1 on monocytes was significantly lower at the stage of severe sepsis/shock than at the stage of sepsis.

CONCLUSIONS

Decrease of the expression of TREM-1 on the membrane of monocytes and neutrophils upon transition from sepsis to severe sepsis/septic shock depends on the underlying type of infection and the causative pathogen.

Clinical practice guidelines for hospital-acquired pneumonia and ventilator-associated pneumonia in adults

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are important causes of morbidity and mortality, with mortality rates approaching 62%. HAP and VAP are the second most common cause of nosocomial infection overall, but are the most common cause documented in the intensive care unit setting. In addition, HAP and VAP produce the highest mortality associated with nosocomial infection. As a result, evidence-based guidelines were prepared detailing the epidemiology, microbial etiology, risk factors and clinical manifestations of HAP and VAP. Furthermore, an approach based on the available data, expert opinion and current practice for the provision of care within the Canadian health care system was used to determine risk stratification schemas to enable appropriate diagnosis, antimicrobial management and nonantimicrobial management of HAP and VAP. Finally, prevention and risk-reduction strategies to reduce the risk of acquiring these infections were collated. Future initiatives to enhance more rapid diagnosis and to effect better treatment for resistant pathogens are necessary to reduce morbidity and improve survival.

Proinflammatory cytokine surge after injury stimulates an airway immunoglobulin a increase

BACKGROUND

: Injury stimulates an innate airway IgA response in severely injured patients, which also occurs in mice. Tumor necrosis factor (TNF)-α and interleukin (IL)-1β stimulate the production of polymeric immunoglobulin receptor, the protein required to transport immunoglobulin A (IgA) to mucosal surfaces. Blockade of TNF-α and IL-1β eliminates the airway IgA response to injury. IL-6 stimulates differentiation of B cells into IgA-secreting plasma cells at mucosal sites. We investigated the local and systemic kinetics of TNF-α, IL-1β, and IL-6 after injury in mice. We also hypothesized that injection of exogenous TNF-α, IL-1β, and IL-6 would replicate the airway IgA response to injury.

METHODS

: Experiment 1: male Institute of Cancer Research mice were randomized to uninjured controls (n = 8) or to surgical stress with laparotomy and neck incisions, with killing at 1, 2, 3, 5, or 8 hours after injury (n = 8/group). Bronchoalveolar lavage (BAL) and serum levels of TNF-α, IL-1β, and IL-6 were analyzed by enzyme-linked immunosorbent assay. Experiment 2: male Institute of Cancer Research mice were randomized to uninjured controls (n = 6), injury (surgical stress that was similar to experiment 1 except the peritoneum was left intact, n = 6), or cytokine injection with intraperitoneal injection of recombinant TNF-α, IL-1β, and IL-6. Animals were killed at 2 hours after injury, and nasal airway lavage and BAL IgA were analyzed by enzyme-linked immunosorbent assay.

RESULTS

: Experiment 1: BAL TNF-α, IL-1β, and IL-6 levels increased in bimodal pattern after injury at 3 hours and 8 hours versus controls (p < 0.05). Serum IL-6 did not increase at 3 hours, but did show a significant increase by 5 hours versus control (p < 0.05). Serum levels of TNF-α and IL-1β did not change. Experiment 2: both Injury and combination TNF-α, IL-1β, and IL-6 cytokine injection significantly increased IgA levels in airway lavage (BAL + nasal airway lavage) compared with control (p < 0.01 for both).

CONCLUSIONS

: Airway levels of TNF-α, IL-1β, and IL-6 increase in a bimodal pattern after injury with peaks at 3 hours and 8 hours, which do not correspond to serum changes. The peak at 8 hours is consistent with the known increase in airway IgA after injury. Intraperitoneal injection of a combination exogenous TNF-α, IL-1β, and IL-6 replicates the airway IgA increase after injury. This effect is not seen with individual cytokine injections.

Endotracheal tube biofilm inoculation of oral flora and subsequent colonization of opportunistic pathogens

Endotracheal (ET) tubes accumulate a biofilm during use, which can harbor potentially pathogenic microorganisms. The enrichment of pathogenic strains in the biofilm may lead to ventilator-associated pneumonia (VAP) with an increased morbidity rate in intensive care units. We used quantitative PCR (qPCR) and gene surveys targeting 16S rRNA genes to quantify and identify the bacterial community to detect fastidious/nonculturable organisms present among extubated ET tubes. We collected eight ET tubes with intubation periods between 12 h and 23 d from different patients in a surgical and a medical intensive care unit. Our qPCR data showed that ET tubes were colonized within 24 h. However, the variation between patients was too high to find a positive correlation between the bacterial load and intubation period. We obtained 1263 near full-length 16S rRNA gene sequences from the diverse bacterial communities. Over 70% of these sequences were associated with genera of typical oral flora, while only 6% were associated with gastrointestinal flora. The most common genus identified was Streptococcus (348/1263), followed by Prevotella (179/1263), and Neisseria (143/1263) with the highest relative concentrations for ET tubes with short intubation periods, indicating oral inoculation of the ET tubes. Our study also shows that even though potentially pathogenic bacteria existed in ET tube biofilms within 24 h of intubation, a longer intubation period increases the opportunity for these organisms to proliferate. In the ET tube that was in place for 23 d, 95% of the sequences belonged to Pseudomonas aeruginosa, which is a bacterial pathogen that is known to out compete commensal bacteria in biofilms, especially during periods of antibiotic treatment. Harboring such pathogens in ET biofilms may increase the chance of VAP, and should be aggressively monitored and prevented.

Pro- and synbiotics to control inflammation and infection in patients with multiple injuries

BACKGROUND

A recent randomized clinical trial of our group disclosed considerable reduction of the infective sequelae after administration of a synbiotic formula, namely Synbiotic 2000FORTE, in patients with multiple injuries, the latter being a preparation of four probiotics. The mechanism of action of synbiotics was studied.

METHODS

A total of 72 patients with severe multiple injuries were allocated to a 15-day administration of either placebo or the synbiotic formula. The association of bloodstream infections, ventilator-associated pneumonia (VAP), serum levels of C-reactive protein (CRP), and endotoxins (LPS) were studied.

RESULTS

Sepsis in the field of bacteremia occurred in 13 patients treated with placebo (36.1%) compared with 5 patients treated with Synbiotic 2000FORTE (13.9%, p = 0.028 between groups). The time to progression to primary bacteremia was longer among patients treated with Synbiotic 2000FORTE compared with placebo (p = 0.0237 between groups). Twelve (33.3%) and five (13.9%) placebo-treated and probiotic-treated patients, respectively, developed ventilator-associated pneumonia with Acinetobacter baumannii as a bacterial cause (p = 0.047 between groups). Treatment with synbiotics was accompanied by reduction of white blood cell counts and LPS and CRP levels in either patients who did or did not develop sepsis.

CONCLUSIONS

Synbiotics contained in the studied formula decrease significantly the risk for sepsis by bloodstream infections and the occurrence of VAP by A. baumannii. The mechanisms of action might involve direct immunomodulatory effect, prevention of bacterial translocation, or most likely a combination of both.

ICU nurses' oral-care practices and the current best evidence

PURPOSE

The purpose of this study was to describe the oral-care practices of ICU nurses, to compare those practices with current evidence-based practice, and to determine if the use of evidence-based practice was associated with personal demographic or professional characteristics.

DESIGN

A national survey of oral-care practices of ICU nurses was conducted using a convenience sample of 218 practicing ICU nurses in 2004-05. The survey instrument included questions about demographic and professional characteristics and a checklist of oral-care practices. Nurses rated their perceived level of priority concerning oral care on a scale from 0 to 100. A score was computed representing the sum of 14 items related to equipment, solutions, assessments, and techniques associated with the current best evidence. This score was then statistically analyzed using ANOVA to determine differences of EBP based on demographic and professional characteristics.

FINDINGS

The most commonly used equipment was gauze pads (84%), followed by tongue depressors (55%), and toothbrushes (34%). Chlorhexidine was the most common solution used (75%). Less than half (44%) reported brushing their patients' teeth. The majority performed an oral assessment before beginning oral care (71%); however, none could describe what assessment tool was used. Only 57% of nurses reported documenting their oral care. Nurses rated oral care of intubated patients with a priority of 67+/-27.1. Wide variations were noted within and between units in terms of which techniques, equipment, and solutions were used. No significant relationships were found between the use of an evidence-based protocol and demographic and professional characteristics or with the priority given to oral care.

CONCLUSIONS

While nurses ranked oral care a high priority, many did not implement the latest evidence into their current practice. The level of research utilization was not related to personal or professional characteristics. Therefore attempts should be made to encourage all ICU nurses to introduce and use evidence-based, oral-care protocols.

CLINICAL RELEVANCE

Practicing ICU nurses in this survey were often not adhering to the latest evidence-based practice and therefore need to be educated and encouraged to do so in order to improve patient care.

Evidence for the participation of soluble triggering receptor expressed on myeloid cells-1 in the systemic inflammatory response syndrome after multiple trauma

BACKGROUND

Based on the implication of soluble triggering receptor expressed on myeloid cells (sTREM-1) in the septic cascade, it was investigated whether it participates or not in posttraumatic systemic inflammatory response syndrome (SIRS).

METHODS

Blood was sampled on days 1, 4, 7, and 15 from 69 patients with SIRS after multiple injuries and upon presentation of a septic complication. Concentrations of sTREM-1, tumor necrosis factor-alpha (TNFalpha), interleukin (IL)-6, IL-8, and interferon-gamma were determined by an enzyme immunoassay. Samples drawn on day 1 from 10 trauma patients without SIRS served as controls.

RESULTS

In 26 patients with SIRS without septic complication, sTREM-1, TNFalpha, and IL-8 remained stable over follow-up; IL-6 decreased and interferon-gamma increased on days 4 and 7 compared with day 1. TNFalpha was the only variable being higher upon advent of septic shock compared with patients without SIRS and upon presentation of SIRS, sepsis, and severe sepsis (p of comparisons with all subgroups <0.0001). Mortality of patients with sTREM-1 greater than 180 pg/mL was 5.3% compared with 28.0% of those with sTREM-1 lower than 180 pg/mL (p 0.035). sTREM-1 higher than 40 pg/mL had sensitivity 56.5% and specificity 91.7% for the differential diagnosis between SIRS and sepsis after multiple injuries.

CONCLUSIONS

This is the first study providing evidence about the participation of sTREM-1 in posttraumatic SIRS. Its levels are increased and remain constant over time in patients who did not develop any complications whereas it seems to behave as an anti-inflammatory mediator.

Kinetics of angiopoietin-2 in serum of multi-trauma patients: correlation with patient severity

BACKGROUND

Angiopoietin-2 (Ang-2) is considered a proinflammatory mediator promoting vascular leakage. Its participation in the inflammatory process following multiple injuries was investigated.

METHODS

Blood was sampled on consecutive days from 54 patients with multiple injuries and six healthy volunteers. Ang-2 was estimated in serum by an enzyme immunoassay.

RESULTS

From the enrolled patients, 10 did not develop any complication; 17 developed systemic inflammatory response syndrome (SIRS); 16 developed sepsis and 11 severe sepsis. Among those who did not develop any complication, all survived. Ang-2 was increased on days 4 and 7 of follow-up in patients with SIRS. Ang-2 was highly increased upon advent of sepsis and of severe sepsis. Patients with serum levels below 15,200 pg/ml survived longer compared to those with levels above 15,200 pg/ml (p=0.015). OR for death with serum Ang-2 above 15,200 pg/ml was 4.00 (p=0.037).

CONCLUSIONS

Serum levels of Ang-2 in multi-trauma patients are increased upon advent of septic complications and they are connected with bad prognosis. Its exact role in the process of multiple trauma remains to be defined.

Incidence and clinical outcomes of ventilator-associated pneumonia in liver transplant and non-liver transplant surgical patients

The aim of this study was to compare the incidence of ventilator-associated pneumonia (VAP) and clinical outcome among patients undergoing orthotopic liver transplantation (OLT) admitted to our surgical intensive care unit (ICU). Patients with an ICU stay longer than 4 days who had undergone surgery within 48 hours of admission were included in the study. Patients were subdivided into a liver transplant group (OLT) and no-liver transplant group (noLT). Diagnosis of VAP was based on microbiological data with a positive culture from a sample collected >or=48 hours after admission. VAP was defined as early if the positive culture occurred within the 4th day of admission, and late if after the 4th day. Three hundred seventy-three noLT and 71 OLT patients showed no differences in sex, mean severity score on admission (SAPS II), length of stay, and outcomes. The incidence of VAP was also similar in the 2 groups (27.3% in the noLT group vs 25.3% in the OLT group). Both in the OLT and noLT groups, the VAP patients showed higher (P< .05) SAPS II scores on admission, length of ICU stay, and mortality rates than the non-VAP patients, without any difference between the 2 groups. VAP is a frequent complication in ICU surgical patients, particularly those with high severity scores on admission. In an ICU surgical population, liver transplantation per se does not seem to increase the patients' risk either for VAP acquisition or for bad outcomes.

Effect of clarithromycin in patients with sepsis and ventilator-associated pneumonia

BACKGROUND

Because clarithromycin provided beneficiary nonantibiotic effects in experimental studies, its efficacy was tested in patients with sepsis and ventilator-associated pneumonia (VAP).

METHODS

Two hundred patients with sepsis and VAP were enrolled in a double-blind, randomized, multicenter trial from June 2004 until November 2005. Clarithromycin (1 g) was administered intravenously once daily for 3 consecutive days in 100 patients; another 100 patients were treated with placebo. Main outcomes were resolution of VAP, duration of mechanical ventilation, and sepsis-related mortality within 28 days.

RESULTS

The groups were well matched with regard to demographic characteristics, disease severity, pathogens, and adequacy of the administered antimicrobials. Analysis comprising 141 patients who survived revealed that the median time for resolution of VAP was 15.5 days and 10.0 days among placebo- and clarithromycin-treated patients, respectively (P = .011); median times for weaning from mechanical ventilation were 22.5 days and 16.0 days, respectively (p = .049). Analysis comprising all enrolled patients showed a more rapid decrease of the clinical pulmonary infection score and a delay for advent of multiple organ dysfunction in clarithromycin-treated patients, compared with those of placebo-treated patients (p = .047). Among the 45 patients who died of sepsis, time to death was significantly prolonged in clarithromycin-treated compared with placebo-treated patients (p = .004). Serious adverse events were observed in 0% and 3% of placebo- and clarithromycin-treated patients, respectively (P = .25).

CONCLUSIONS

Clarithromycin accelerated the resolution of VAP and weaning from mechanical ventilation in surviving patients and delayed death in those who died of sepsis. The mortality rate at day 28 was not altered. Results are encouraging and render new perspectives on the management of sepsis and VAP.

Patient's self-determination in intensive care-from an action- and confirmation theoretical perspective. The intensive care nurse view

When becoming an intensive care patient life changes dramatically. In order to save life, different actions are performed by the caregivers and the patient's ability to exercise self-determination is non-existent. After the acute phase the patient is more awake and the possibilities for self-determination change. The purpose of this study was to describe intensive care nurses' (ICNs) views of patient's self-determination in an intensive care unit and to systematize ICNs' nursing actions for supporting patient's self-determination from an action- and confirmation-theoretic perspective. In order to answer these questions, 17 interviews with ICNs were conducted by the use of the Critical Incident Technique (CIT). The transcripts were then analysed using a hermeneutic analysis method and structured by the SAUC model for confirming nursing. The main findings were that the ICN thought that the ICU patient's self-determination was low and restricted. It was more common that the ICN acted to strengthen the patient's self-determination in nursing care, but there were no specific nursing goals for patient's self-determination. The most common actions for supporting self-determination were supplying the patient with information and engaging the patient in making a day plan. The nursing implications are that the ICN's view of human being as an acting subject is important for the ICN's awareness to recognise the patient's own personal resources to handle the critically ill situation and that the ICN's competence to manifest qualified nursing is necessary for strengthening patient's self-determination.

Impact of oral hygiene on prevention of ventilator-associated pneumonia in neuroscience patients

Ventilator-associated pneumonia is one of the most frequent complications among critically ill patients. Growth of pathogenic bacteria in dental plaque may serve as the source of these infections. This performance improvement initiative evaluated an aggressive oral care approach to prevent the accumulation of plaque containing bacteria. Our data support the use of these oral care measures and deep oral-pharyngeal suctioning for the prevention of aspiration of oral contents.

Nosocomial pneumonia in the ICU: a prospective cohort study

Ventilator-associated pneumonia (VAP) is the most common intensive care unit (ICU)-acquired infection among patients requiring mechanical ventilation. A prospective surveillance programme of all patients has been implemented at the ICU, Karolinska University Hospital, Sweden since 2001. Within this programme, incidence and risk factors for ICU-acquired pneumonia and associated death over a 2-y period have been studied. Of 329 patients enrolled in the study, 221 required mechanical ventilation. 33 of 221 patients (15%) developed VAP, corresponding to a rate of 29 VAP/1000 ventilator d. Risk factors for VAP were aspiration (hazard ratio 3.79; 95% CI 1.48-9.68), recent surgery (HR 3.58; 95% CI 1.15-11.10) and trauma (HR 3.00; 95% CI 1.03-8.71). 11 patients of 33 (33%) with VAP died within 28 d compared to 46 of 288 (16%) without ICU-acquired pneumonia (odds ratio 2.73; 95% CI 0.97-7.63). We conclude that: 1) incidence of VAP was 15% and the most important risk factor was aspiration; 2) APACHE II score > or = 20 is a stronger predictor for poor outcome than VAP; 3) a minority of patients with APACHE II score > or = 20 develop VAP; and 4) continuous surveillance programmes are feasible and provide valuable data for improvement of quality of care.

Hospital- and community-acquired infections: a point prevalence and risk factors survey in a tertiary care center in Saudi Arabia

BACKGROUND

Point prevalence studies are useful in revealing the prevalence of hospital-acquired infections (HAIs) and community-acquired infections (CAIs). Such information allows prioritization of infection control resources and aids in overall hospital expenditure cut-backs.

METHODS

A one-day point prevalence survey was conducted on May 19, 2003 at the King Fahad National Guard Hospital in Riyadh. Since the survey included HAIs and CAIs all patients were included. Data were collected on the underlying diagnosis, infection if present and whether it was hospital-acquired or community-acquired. We identified the presence of a line-associated blood stream infection (BSI), ventilator-associated pneumonia (VAP), catheter-associated urinary tract infection (UTI) or a surgical site infection (SSI) based on the United States National Nosocomial Infection Surveillance (NNIS) definitions.

RESULTS

Five hundred and sixty-two inpatients were included in the survey. There were 38 patients with 45 (8.0%) HAIs and 76 (13.5%) patients with a CAI. Of the HAIs, 31.1% had a line-related BSI, while 28.9% and 24.4% had a VAP and catheter-related UTI, respectively. Most of the HAIs took place in the intensive care units (ICU) (21 (46.7%)), followed by the medical and surgical wards with six (13.3%) cases in each ward. For all HAIs there was a 12.7-fold increased risk with a hospital stay exceeding eight days (OR: 12.7, CI 3.2-50.6). Most of the 76 CAIs were admitted to the medical ward with community-acquired pneumonia (34.9%) as the most common diagnosis. Among the 89 pathogens isolated, Pseudomonas aeruginosa was the most common (21.3%) followed by Enterococcus spp (16.9%).

CONCLUSIONS

The overall rate of HAIs in our hospital was 8%, with significant risk factors including a hospital stay exceeding eight days. A device-related infection was more likely in a patient with a venous or bladder catheter in place for more than eight days, or a patient mechanically ventilated for more than eight days. Catheter-related UTIs were identified as an important source of infection, requiring ongoing surveillance.

Hospital-Acquired Pneumonia in the Intensive Care Units of Polish Hospitals

We analyzed the epidemiological characteristics of pneumonia in intensive care units of Polish hospitals. Among 11,587 patients, there were 191 cases of hospital-acquired pneumonia (HAP). The incidence of HAP was 5.6%, and that of ventilator-associated pneumonia (VAP) was 17.9%. The overall mortality rate was 12.6%, and the mortality rate for patients who received artificial ventilation was 15.0%. The predominant organisms causing HAP and VAP were Pseudomonas aeruginosa and Escherichia coli, and 21.1% of Staphylococcus aureus isolates were resistant to methicillin.

Soluble triggering receptor expressed on myeloid cells 1 as an anti-inflammatory mediator in sepsis

OBJECTIVE

To define the significance of soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) in the septic cascade by comparing its kinetics to those of other proinflammatory mediators and of interleukin (IL) 10.

DESIGN

Prospective study in a tertiary unit.

PATIENTS

Blood was sampled from 90 patients with septic syndrome due to ventilator-associated pneumonia for 7 days after the appearance of symptoms. Concentrations of tumor necrosis factor (TNF) alpha, IL-6, IL-8, IL-10, and sTREM-1 were determined by enzyme-linked immunosorbent assay.

RESULTS

Serum levels of TNFalpha, IL-6, IL-10, and sTREM-1 were higher in nonsurvivors than in survivors; similar differences were not found for IL-8. Positive correlations were found between the ratios IL-10/TNFalpha and sTREM-1/TNFalpha, between IL-10/IL-6 and sTREM-1/IL-6, and between IL-10/IL-8 and sTREM-1/IL-8. Median values of IL-10/TNFalpha upon presentation of sepsis, severe sepsis, and septic shock were 3.21, 2.16, and 2.86, respectively (NS). Respective values for sTREM-1/TNFalpha were 21.28, 7.33, and 27.78 (p=0.047 between sepsis and severe sepsis, p=0.003 between severe sepsis and septic shock).

CONCLUSIONS

sTREM-1 follows the kinetics of IL-10 and should therefore be considered an anti-inflammatory mediator in sepsis. Decreased ratios of sTREM-1/TNFalpha might determine transition from sepsis to severe sepsis and from severe sepsis to septic shock.

Does soluble triggering receptor expressed on myeloid cells-1 play any role in the pathogenesis of septic shock?

In order to define the significance of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) upon progression from sepsis or severe sepsis to septic shock a prospective study was designed with 90 enrolled patients with septic syndrome due to ventilator-associated pneumonia. Blood was sampled on seven consecutive days upon initiation of symptoms and concentrations of tumour necrosis factor-alpha (TNFalpha), interleukin-6 (IL-6), IL-8 and sTREM-1 were estimated in serum by an enzymeimmunoassay. No differences in concentrations of TNFalpha, IL-6 and IL-8 were found between patients with sepsis, severe sepsis and septic shock on the first day of presentation of symptoms. Patients presenting with septic shock had concentrations of sTREM-1 significantly higher than both patients with sepsis and severe sepsis on the first day; no difference was found between patients with sepsis and severe sepsis. A positive correlation was detected between sTREM-1 and the white blood cell count. Serum levels of sTREM-1 were significantly lower in patients where VAP resolved compared to those where VAP did not resolve; similar findings were noted between patients who eventually survived and those who died. IL-6 followed the kinetics of sTREM-1 in correlation to patients's prognosis; levels of TNFalpha and IL-8 were unrelated to prognosis. It is concluded that sTREM-1 is particularly increased upon evolution from sepsis or severe sepsis to septic shock. Its sustained increase is an indication of poor outcome. The underlined pathophysiological role of sTREM-1 for the transition from sepsis or severe sepsis to septic shock might constitute a novel target for immunomodulatory therapy.

Defining pneumonia in critically ill infants and children

OBJECTIVE

To define pneumonia in critically ill children in the intensive care unit setting for surveillance of infection and for the design, conduct, and evaluation of clinical trials in the prevention and therapy of lower respiratory tract infections in this population.

DESIGN

Summary of the literature with review and consensus by experts in the field.

RESULTS

A variety of diagnostic criteria from the medical literature, professional societies, and governmental health agencies and regulators were identified. Very few of these diagnostic criteria have been validated for use in children. We propose definitions for definite, possible, and probable pneumonia that build on identified definitions in the literature and use combinations of symptoms, signs, and laboratory criteria. Gaps in knowledge were identified.

CONCLUSIONS

Although pneumonia is one of the most common diagnoses in critically ill children, there have been few studies validating diagnostic criteria. Definitions for definite, probable, and possible community-acquired pneumonia and nosocomial pneumonia were achieved by consensus of experts based on guidelines from governmental agencies, professional organizations, and published literature. Future research should determine the utility of these definitions in the critically ill child and adapt them accordingly.