Is COPD associated with increased risk for microaspiration in intubated critically ill patients?

BACKGROUND: Although COPD patients are at higher risk for aspiration when breathing spontaneously, no information is available on the risk for microaspiration in invasively ventilated COPD patients. The aim of our study was to determine the relationship between COPD and abundant microaspiration in intubated critically ill patients. METHODS: This was a retrospective analysis of prospectively collected data, provided by 3 randomized controlled trials on microaspiration in critically ill patients receiving invasive mechanical ventilation for more than 48 h. Abundant microaspiration was defined as the presence of pepsin and or alpha-amylase at significant levels in tracheal aspirates. In all study patients, pepsin and alpha-amylase were quantitatively measured in all tracheal aspirates collected during a 48-h period. COPD was defined using spirometry criteria. RESULTS: Among the 515 included patients, 70 (14%) had proven COPD. Pepsin and alpha-amylase were quantitatively measured in 3873 and 3764 tracheal aspirates, respectively. No significant difference was found in abundant microaspiration rate between COPD and non-COPD patients (62 of 70 patients (89%) vs 366 of 445 (82%) patients, p = 0.25). Similarly, no significant difference was found in abundant microaspiration of gastric contents (53% vs 45%, p = 0.28), oropharyngeal secretions (71% vs 71%, p = 0.99), or VAP (19% vs 22%, p = 0.65) rates between the two groups. No significant difference was found between COPD and non-COPD patients in duration of mechanical ventilation, ICU length of stay, or ICU mortality. CONCLUSIONS: Our results suggest that COPD is not associated with increased risk for abundant microaspiration in intubated critically ill patients.

Impact of tapered-cuff tracheal tube on microaspiration of gastric contents in intubated critically ill patients: a multicenter cluster-randomized cross-over controlled trial.

PURPOSE: Studies on the impact of tapered-cuff tracheal tubes on rates of microaspiration and ventilator-associated pneumonia (VAP) in intubated patients have reported conflicting results. The aim of this study was to determine the influence of this shape of tracheal cuff on abundant microaspiration of gastric contents in critically ill patients. METHODS: All patients intubated in the intensive care unit (ICU) and requiring mechanical ventilation for at least 48 h were eligible for this multicenter cluster-randomized controlled cross-over open-label study. The primary outcome was abundant microaspiration of gastric contents, defined by the presence of pepsin at significant level in >30% of tracheal aspirates. Quantitative measurement of pepsin and salivary amylase was performed in all tracheal aspirates during the 48 h following enrollment. RESULTS: A total of 326 patients were enrolled in the ten participating ICUs (162 in the PVC tapered-cuff group and 164 in the standard-cuff group). Patient characteristics were similar in the two study groups. The proportion of patients with abundant microaspiration of gastric contents was 53.5% in the tapered-cuff and 51.0% in the standard-cuff group (odds ratio 1.14, 95% CI 0.72-1.82). While abundant microaspiration of oropharyngeal secretions was not significantly different (77.4 vs 68.6%, p = 0.095), the proportion of patients with tracheobronchial colonization was significantly lower (29.6 vs 43.3%, p = 0.01) in the tapered-cuff than in the standard-cuff group. No significant difference between the two groups was found for other secondary outcomes, including ventilator-associated events and VAP. CONCLUSIONS: This trial showed no significant impact of tapered-cuff tracheal tubes on abundant microaspiration of gastric contents. TRIAL REGISTRATION: ClinicalTrials.gov, number NCT01948635.

Impact of combination therapy and early de-escalation on outcome of ventilator-associated pneumonia caused by Pseudomonas aeruginosa.

BACKGROUND: Pseudomonas aeruginosa is a common cause of ventilator-associated pneumonia (VAP). Guidelines recommend dual coverage of P. aeruginosa, but the beneficial effect of combination therapy is controversial. We described antibiotic prescriptions and evaluated the clinical impact of initial combination antibiotic therapy and de-escalation strategy in patients with VAP caused by P. aeruginosa. METHODS: Between 1994 and 2014, all 100 patients with VAP caused by P. aeruginosa in our intensive care unit (ICU) were included in a retrospective cohort study to evaluate the prognostic impact of initial combination antibiotic therapy. RESULTS: Eighty-five patients received initial combination antibiotic therapy and 15 monotherapy. Nine patients received inadequate initial antibiotic therapy. De-escalation was performed in 42 patients. Thirty-nine patients died in the ICU. Factors independently associated with death were SAPS II score [SAPS II ≥40 versus <40: hazard ratio (HR) 2.49, 95% confidence interval (CI) 1.08-5.70, p = 0.03] and septic shock (HR = 4.80, 95% CI = 1.90-12.16, p < 0.01) at onset of VAP. Initial combination antibiotic therapy (HR = 1.97, 95% CI = 0.56-6.93, p = 0.29) and early de-escalation (HR = 0.59, 95% CI = 0.27-1.31, p = 0.19) had no impact on mortality. In multivariate analysis, the risk for inappropriate initial antibiotic therapy was higher in cases with multi-drug resistant P. aeruginosa [odd ratio (OR) = 7.11, 95% CI = 1.42-35.51, p = 0.02], but lower in cases with initial combination antibiotic therapy (OR = 0.12, 95% CI = 0.02-0.63, p = 0.01). CONCLUSION: In our cohort, combination therapy increased the likelihood of appropriate therapy but did not seem to impact on mortality.

Comparison of terminal extubation and terminal weaning as mechanical ventilation withdrawal in ICU patients.

BACKGROUND: Terminal extubation (TE) is applied in some Intensive Care Units (ICU) patients when a decision of withdrawal of mechanical ventilation is decided. Other units prefer terminal weaning (TW) with no removal of the endotracheal tube. We report our experience with these two procedures. METHODS: We conducted a retrospective study analyzing patients deceased in our ICU after a decision of life sustained therapy (LST) during the year 2013. TE was proposed to family members for patients presenting with two medical conditions: lack of vasoactive drugs (VAD) and SaO2>95% with a FIO2<50%. TW, defined by the reduction of oxygenation and/or the discontinuation of VAD, was proposed for patients receiving a FIO2≥50% and/or VAD. The two procedures were performed after obtaining a Cambridge Score-5 with sedatives. RESULTS: Sixty eight patients died after withdrawal of LST. TE was performed for 22 patients and TW for 46. There was no difference in mean age, mean length of ICU stay, cause of ICU admission and dose of sedatives used during withdrawal procedure between the two groups. All family members approved the decision of TE. In this group, family members of each patient were present in ICU room at time of death, while they were present at this moment for 32 (69.5%) patients with TW. CONCLUSIONS: In our Unit, TE is a practice largely approved by family members. This procedure does not require higher doses of sedatives and allows the nearest relatives to be present at time of death.

The use of static and dynamic haemodynamic parameters before volume expansion: A prospective observational study in six French intensive care units.

OBJECTIVE: The aim of the present study was to determine the use of static and dynamic haemodynamic parameters for predicting fluid responsiveness prior to volume expansion (VE) in intensive care unit (ICU) patients with systemic inflammatory response syndrome (SIRS). METHODS: We conducted a prospective, multicentre, observational study in 6 French ICUs in 2012. ICU physicians were audited concerning their use of static and dynamic haemodynamic parameters before each VE performed in patients with SIRS for 6 consecutive weeks. RESULTS: The median volume of the 566 VEs administered to patients with SIRS was 1000mL [500-1000mL]. Although at least one static or dynamic haemodynamic parameter was measurable before 99% (95% CI, 99%-100%) of VEs, at least one them was used in only 38% (95% CI, 34%-42%) of cases: static parameters in 11% of cases (95% CI, 10%-12%) and dynamic parameters in 32% (95% CI, 30%-34%). Static parameters were never used when uninterpretable. For 15% of VEs (95% CI, 12%-18%), a dynamic parameter was measured in the presence of contraindications. Among dynamic parameters, respiratory variations in arterial pulse pressure (PPV) and passive leg raising (PLR) were measurable and interpretable before 17% and 90% of VEs, respectively. CONCLUSIONS: Haemodynamic parameters are underused for predicting fluid responsiveness in current practice. In contrast to static parameters, dynamic parameters are often incorrectly used in the presence of contraindications. PLR is more frequently valid than PPV for predicting fluid responsiveness in ICU patients.

Impact of tracheal cuff shape on microaspiration of gastric contents in intubated critically ill patients: study protocol for a randomized controlled trial.

BACKGROUND: Ventilator-associated pneumonia (VAP) is the most common infection in intubated critically ill patients. Microaspiration of the contaminated gastric and oropharyngeal secretions is the main mechanism involved in the pathophysiology of VAP. Tracheal cuff plays an important role in stopping the progression of contaminated secretions into the lower respiratory tract. Previous in vitro studies suggested that conical cuff shape might be helpful in improving tracheal sealing. However, clinical studies found conflicting results. The aim of this study is to determine the impact of conical tracheal cuff shape on the microaspiration of gastric contents in critically ill patients. METHODS/DESIGN: This prospective cluster randomized controlled crossover open-label trial is currently being conducted in ten French intensive care units (ICUs). Patients are allocated to intubation with a polyvinyl chloride (PVC) standard (barrel)-shaped or a PVC conical-shaped tracheal tube. The primary objective is to determine the impact of the conical shaped tracheal cuff on abundant microaspiration of gastric contents. Secondary outcomes include the incidence of microaspiration of oropharyngeal secretions, tracheobronchial colonization, VAP and ventilator-associated events. Abundant microaspiration is defined as the presence of pepsin at significant level (>200 ng/ml) in at least 30 % of the tracheal aspirates. Pepsin and amylase are quantitatively measured in all tracheal aspirates during the 48 h following inclusion. Quantitative tracheal aspirate culture is performed at inclusion and twice weekly. We plan to recruit 312 patients in the participating ICUs. DISCUSSION: BEST Cuff is the first randomized controlled study evaluating the impact of PVC tracheal-cuff shape on gastric microaspirations in patients receiving invasive mechanical ventilation. Enrollment began in June 2014 and is expected to end in October 2015. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01948635 (registered 31 August 2013).

Volume expansion in the first 4 days of shock: a prospective multicentre study in 19 French intensive care units.

PURPOSE: To describe the current practices of volume expansion in French intensive care units (ICU). METHODS: In 19 ICUs, we prospectively observed the prescription and monitoring practices of volume expansion in consecutive adult patients with shock [sustained hypotension and/or need of vasopressor therapy, associated with at least tachycardia and/or sign (s) of hypoperfusion]. Patients were included at the time of prescription of the first fluid bolus (FB). Thereafter, all the FBs administered during the 96 h following shock onset were surveyed. An FB was defined as an intravenous bolus of at least 100 ml of a blood volume expander intended to rapidly improve the patient's circulatory condition. RESULTS: We included 777 patients [age: 63 ± 15 years; female gender: 274 (35 %); simplified acute physiology score II: 55.9 ± 20.6; ICU length of stay: 6 days (interquartile range (IQR) 3-13); ICU mortality: 32.8 %] and surveyed 2,694 FBs. At enrolment mean arterial pressure was 63 mmHg (IQR 55-71). The most frequent triggers of FB were hypotension, low urine output, tachycardia, skin mottling and hyperlactataemia. Amount of fluid given at each FB was highly variable between centres. Crystalloids were used in 91 % (2,394/2,635) and synthetic colloids in 3.3 % (87/2,635) of FBs. Overall, clinicians used any kind of haemodynamic assessment (central venous pressure measurement, predictive indices of fluid responsiveness, echocardiography, cardiac output monitoring or a combination of these) in 23.6 % (635/2,694) of all FBs surveyed, with an important between-centre heterogeneity. CONCLUSIONS: High between-centre variability characterised all the aspects of FB prescription and monitoring, but overall haemodynamic exploration to help guide and monitor FB was infrequent.

Wavefront kinetics of plasma oxidation of polydimethylsiloxane: limits for sub-µm wrinkling.

We investigate the surface plasma oxidation of polydimethylsiloxane (PDMS) elastomers and its implication for the morphologies attainable by wrinkling of glassy-elastomer 'bilayers'. The kinetics of glassy skin formation is found to follow a logarithmic dependence with plasma exposure time t and, for various plasma intensities I, the relevant control variable is shown to be dose (≡I × t). We model the mechanism and kinetics of glassy film formation by plasma oxidation with a frontal propagation coarse-grained model, describing the spatio-temporal evolution of a conversion order parameter (ϕ) orthogonal to the film surface. The model is validated by X-ray reflectivity experiments, which confirm the logarithmic growth and quantify the initial growth of a transient, incomplete, skin layer during the early stage of plasma exposure. Three regimes are identified as (I) induction, (II) formation and (III) propagation with a combination of X-ray and wrinkling experiments. The simultaneous increase in thickness and skin mechanical modulus is found to be responsible for an unexpected minimum wavelength λmin attainable, which depends on critical strain εc and is ultimately limited by mechanical failure of the elastomer (λmin ≃ 140 nm is demonstrated at ε = 200%). We conclude by establishing a 1D surface morphology diagram, in terms of wavelength λ and amplitude A, limitations and capabilities for producing highly ordered (sub-)micropatterns over macroscopic areas using plasma oxidised PDMS under uniaxial strain.

Improvement in process of care and outcome in patients requiring intensive care unit admission for community acquired pneumonia.

BACKGROUND: The present study was performed to assess the prognosis of patients admitted to the intensive care unit (ICU) for community acquired pneumonia (CAP) after implementation of new processes of care. METHODS: Two groups of patients with CAP were admitted to a 16-bed multidisciplinary ICU in an urban teaching hospital during two different periods: the years 1995-2000, corresponding to the historical group; and 2005-2010, corresponding to the intervention group. New therapeutic procedures were implemented during the period 2005-2010. These procedures included a sepsis management bundle derived from the Surviving Sepsis Campaign, use of a third-generation cephalosporin and levofloxacin as the initial empirical antimicrobial regimen, and noninvasive mechanical ventilation following extubation. RESULTS: A total of 317 patients were studied: 142 (44.8%) during the historical period and 175 (55.2%) during the intervention period. Sequential Organ Failure Assessment scores were higher in patients in the intervention group (7.2 ± 3.7 vs 6.2 ± 2.8; p=0.008). Mortality changed significantly between the two studied periods, decreasing from 43.6% in the historical group to 30.9% in the intervention group (p < 0.02). A restrictive transfusion strategy, use of systematic postextubation noninvasive mechanical ventilation in patients with severe chronic respiratory or cardiac failure patients, less frequent use of dobutamine and/or epinephrine in patients with sepsis or septic shock, and delivery of a third-generation cephalosporin associated with levofloxacin as empirical antimicrobial therapy were independently associated with better outcomes. CONCLUSION: Positive outcomes in ICU patients with CAP have significantly increased in our ICU in recent years. Many new interventions have contributed to this improvement.

Should highly active antiretroviral therapy be prescribed in critically ill HIV-infected patients during the ICU stay? A retrospective cohort study.

BACKGROUND: The impact of highly active antiretroviral therapy (HAART) in HIV-infected patients admitted to the intensive care unit (ICU) remains controversial. We evaluate impact of HAART prescription in HIV-infected patients admitted to the ICU of Tourcoing Hospital from January 2000 to December 2009. RESULTS: There were 91 admissions concerning 85 HIV-infected patients. Reasons for ICU admission were an AIDS-related diagnosis in 46 cases (51%). Fifty two patients (57%) were on HAART at the time of ICU admission, leading to 21 immunovirologic successes (23%). During the ICU stay, HAART was continued in 29 patients (32%), and started in 3 patients (3%). Only one patient experienced an adverse event related to HAART. Mortality rate in ICU and 6 months after ICU admission were respectively 19% and 27%. Kaplan-Meier estimates of the cumulative unajusted survival probability over 6 months were higher in patients treated with HAART during the ICU stay (Log rank: p = 0.04). No benefit of HAART in ICU was seen in the adjusted survival proportion at 6 months or during ICU stay. Prescription of HAART during ICU was associated with a trend to lower incidence of new AIDS-related events at 6 months (respectively 17% and 34% with and without HAART, p = 0.07), and with higher incidence of antiretroviral resistance after ICU stay (respectively 25% and 7% with and without HAART, p = 0.02). CONCLUSIONS: Our results suggest a lower death rate over 6 months in critically ill HIV-infected patients taking HAART during ICU stay. The optimal time to prescribe HAART in critically ill patients needs to be better defined.

Survival in critically ill patients with acute kidney injury treated with early hemodiafiltration.

PURPOSE: Early renal replacement therapy (RRT) initiation should theoretically influence many physiological disorders related to acute kidney injury (AKI). Currently, there is no consensus about RRT timing in intensive care unit (ICU) patients. METHODS: We performed a retrospective analysis of all critically ill patients who received RRT in our ICU during a 3 year-period. Our goal was to identify mortality risk factors and if RRT initiation timing had an impact on survival. RRT timing was calculated from the moment the patient was classified as having acute kidney injury in the RIFLE classification. RESULTS: A hundred and ten patients received RRT. We identified four independent mortality risk factors: need for mechanical ventilation (OR = 12.82 (1.305 - 125.868, p = 0.0286); RRT initiation timing >16 h (OR = 5.66 (1.954 - 16.351), p = 0.0014); urine output on admission <500 ml/day (OR = 4.52 (1.666 - 12.251), p = 0.003); and SAPS II on admission >70 (OR = 3.45 (1.216 - 9.815), p = 0.02). The RRT initiation =16 h and RRT initiation >16 h groups presented the same baseline characteristics, except for more severe gravity scores and kidney failure in the early RRT group. CONCLUSIONS: Early RRT in ICU patients with acute kidney injury or failure was associated with increased survival.

Severe pneumococcal pneumonia: impact of new quinolones on prognosis.

BACKGROUND: Most guidelines have been proposing, for more than 15 years, a ß-lactam combined with either a quinolone or a macrolide as empirical, first-line therapy of severe community acquired pneumonia (CAP) requiring ICU admission. Our goal was to evaluate the outcome of patients with severe CAP, focusing on the impact of new rather than old fluoroquinolones combined with ß-lactam in the empirical antimicrobial treatments. METHODS: Retrospective study of consecutive patients admitted in a 16-bed general intensive care unit (ICU), between January 1996 and January 2009, for severe (Pneumonia Severity Index > or = 4) community-acquired pneumonia due to non penicillin-resistant Streptococcus pneumoniae and treated with a ß-lactam combined with a fluoroquinolone. RESULTS: We included 70 patients of whom 38 received a ß-lactam combined with ofloxacin or ciprofloxacin and 32 combined with levofloxacin. Twenty six patients (37.1%) died in the ICU. Three independent factors associated with decreased survival in ICU were identified: septic shock on ICU admission (AOR = 10.6; 95% CI 2.87-39.3; p = 0.0004), age > 70 yrs. (AOR = 4.88; 95% CI 1.41-16.9; p = 0.01) and initial treatment with a ß-lactam combined with ofloxacin or ciprofloxacin (AOR = 4.1; 95% CI 1.13-15.13; p = 0.03). CONCLUSION: Our results suggest that, when combined to a ß-lactam, levofloxacin is associated with lower mortality than ofloxacin or ciprofloxacin in severe pneumococcal community-acquired pneumonia.

Epidemiology, prognosis, and evolution of management of septic shock in a French intensive care unit: a five years survey.

Purpose. To evaluate the epidemiology, prognosis, and management of septic shock patients hospitalized in our intensive care unit (ICU). Materiel and Methods. Five-year monocenter observational study including 320 patients. Results. ICU mortality was 54.4%. Independent mortality risk factors were mechanical ventilation (OR = 4.97), Simplify Acute Physiology Score (SAPS) II > 60 (OR = 4.28), chronic alcoholism (OR = 3.38), age >65 years (OR = 2.65), prothrombin ratio <40% (OR = 2.37), and PaO(2)/FiO(2) ratio <150 (OR = 1.91). These six mortality risk factors recovered allow screening immediately septic shock patients with a high mortality risk. Morbidity improved with time (diminution of septic shock complications, increase of the number of days alive free from mechanical ventilation and vasopressors on day 28), concomitant to an evolution of the management (earlier institution of all replacement and medical therapies and more initial volume expansion). There was no difference in mortality. Conclusion. Our study confirms a high mortality rate in septic shock patients despite a new approach of treatment.

Resuscitation with low volume hydroxyethylstarch 130 kDa/0.4 is not associated with acute kidney injury.

INTRODUCTION: Acute kidney injury (AKI) in the ICU is associated with poorer prognosis. Hydroxyethylstarch (HES) solutions are fluid resuscitation colloids frequently used in the ICU with controversial nephrotoxic adverse effects. Our study objective was to evaluate HES impact on renal function and organ failures. METHODS: This observational retrospective study included 363 patients hospitalized for more than 72 hours in our ICU. A hundred and sixty eight patients received HES during their stay and 195 did not. We recorded patients' baseline characteristics on admission and type and volume of fluid resuscitation during the first 3 weeks of ICU stay. We also noted the evolution of urine output, the risk of renal dysfunction, injury to the kidney, failure of kidney function, loss of kidney function and end-stage kidney disease (RIFLE) classification and sepsis related organ failure assessment (SOFA) score over 3 weeks. RESULTS: Patients in the HES group were more severely ill on admission but AKI incidence was similar, as well as ICU mortality. The evolution of urine output (P = 0.74), RIFLE classification (P = 0.44) and SOFA score (P = 0.23) was not different. However, HES volumes administered were low (763+/-593 ml during the first 48 hours). CONCLUSIONS: Volume expansion with low volume HES 130 kDa/0.4 was not associated with AKI.

Nanostructured wrinkled surfaces for templating bionanoparticles--controlling and quantifying the degree of order.

We present a novel method to align the tobacco mosaic virus (TMV) on topographically structured surfaces. In order to gain defined patterns we use wrinkled polydimethlysiloxane (PDMS) sheets as templates. We aligned the virus with a simple spin-coating procedure on the PDMS sheet. The concentration of the virus solution and the spin speed are varied in order to identify ideal conditions for the arrangement of the viruses on the wrinkled templates. Here, we establish a simple analytical approach which allows quantifying the degree of order of the patterns, which is the basis for a quantitative discussion of templating efficiency. Furthermore, we discuss the role of dewetting processes for the particle assembly. TMVs can be used as reactive nanoparticles due to their well-defined surface chemistry. They can as well serve as a model system for alignment of anisotropic particles via spin coating from solution.

A lithography-free pathway for chemical microstructuring of macromolecules from aqueous solution based on wrinkling.

We report on a novel lithography-free method for obtaining chemical submicron patterns of macromolecules on flat substrates. The approach is an advancement of the well-known microcontact printing scheme: While for classical microcontact printing lithographically produced masters are needed, we show that controlled wrinkling can serve as an alternative pathway to producing such masters. These can even show submicron periodicities. We expect upscaling to larger areas to be considerably simpler than that for existing techniques, as wrinkling results in a macroscopic deformation process that is not limited in terms of substrate size. Using this approach, we demonstrate successful printing of aqueous solutions of polyelectrolytes and proteins. We study the effectiveness of the stamping process and its limits in terms of periodicities and heights of the stamps' topographical features. We find that critical wavelengths are well below 355 nm and critical amplitudes are below 40 nm and clarify the failure mechanism in this regime. This will permit further optimization of the approach in the future.

A pilot randomized study comparing high and low volume hemofiltration on vasopressor use in septic shock.

OBJECTIVE: High volume hemofiltration (HVHF) has shown potential benefits in septic animals and a few reports suggested a hemodynamic improvement in humans. However, randomized studies are still lacking. Our goal was to evaluate the hemodynamic effects of HVHF in septic shock patients with acute renal failure (ARF). DESIGN AND SETTING: Prospective randomized study in an intensive care unit (ICU). PATIENTS: Twenty patients with septic shock and ARF. INTERVENTIONS: Patients were randomized to either high volume hemofiltration [HVHF 65 ml/(kg h)] or low volume hemofiltration [LVHF 35 ml/(kg h). Vasopressor dose was adjusted to reach a mean arterial pressure (MAP) > 65 mmHg. MEASUREMENTS AND RESULTS: We performed six hourly measurements of MAP, norepinephrine dose, PaO(2)/FiO(2) and lactate, and four daily urine output and logistic organ dysfunction (LOD) score. Baseline characteristics of the two groups were comparable on randomization. Mean norepinephrine dose decreased more rapidly after 24 h of HVHF treatment compared to LVHF treatment (P = 0.004) whereas lactate and PaO(2)/FiO(2) did not differ between the two treatment groups. During the 4-day follow-up, urine output was slightly increased in the HVHF group (P = 0.059) but the LOD score evolution was not different. Duration of mechanical ventilation, renal replacement therapy and ICU length of stay were also comparable. Survival on day 28 was not affected. CONCLUSION: HVHF decreased vasopressor requirement and tended to increase urine output in septic shock patients with renal failure. However, a larger trial is required to confirm our results and perhaps to show a benefit in survival.

Validation of a prediction rule for prognosis of severe community-acquired pneumonia.

In a previous study, we developed a prognostic prediction rule, based on nine prognostic variables, capable to estimate and to adjust the mortality rate of patients admitted in intensive care unit for severe community-acquired pneumonia. A prospective multicenter study was undertaken to evaluate the performance of this rule. Five hundred eleven patients, over a 7-year period, were studied. The ICU mortality rate was 29.0%. In the 3 initial risk classes, we observed significantly increasing mortality rates (8.2% in class I, 22.8% in class II and 65.0% in class III) (p<0.001). Within each initial risk class, the adjustment risk score identified subclasses exhibiting significantly different mortality rates: 3.9% and 33.3% in class I; 3.1%, 12.9% and 63.3% in class II; and 55.8% and 82.5% in class III. Compared with mortality rates predicted by our previous study, only a few significant differences were observed. Our results demonstrate the performance and reproductibility of this prognostic prediction rule.

Impact of thrombocytopenia on outcome of patients admitted to ICU for severe community-acquired pneumonia.

OBJECTIVE: To evaluate the prevalence and the prognostic value of thrombocytopenia in patients admitted to ICU for severe community-acquired pneumonia. METHODS: Multicentre observational study was conducted in 7 ICUs in the north of France over a 19-year period (1987-2005). The primary outcome measure was the ICU mortality. RESULTS: Eight hundred and twenty-two patients were studied. A platelet count < 150x10(9)/L was observed at ICU admission in 202 (25%) patients. Admission platelet count was between 101 and 149x10(9)/L, 51 and 100x10(9)/L, 21 and 50x10(9)/L, and < or = 20x10(9)/L in 100, 61, 32 and 9 patients, respectively. ICU mortality rate was 35.4%. Classifying patients into 3 categories with the following cut-offs of platelet count, > or = 150x10(9)/L, 51-149x10(9)/L, and < or = 50x10(9)/L, we observed a significant increase in ICU mortality rates which were 30.8% in the first group, 44.1% in the second group and 70.7% in the last one (p<0.0001). In multivariate analysis, thrombocytopenia < or = 50x10(9)/L appeared as an independent predictor of mortality (AOR=4.386). CONCLUSIONS: In patients admitted to ICU for severe community-acquired pneumonia, thrombocytopenia has a high prevalence and influences the outcome.