Diagnostic Accuracy of the Inferior Vena Cava Collapsibility to Predict Fluid Responsiveness in Spontaneously Breathing Patients With Sepsis and Acute Circulatory Failure.

OBJECTIVE: To investigate whether the collapsibility index of the inferior vena cava recorded during a deep standardized inspiration predicts fluid responsiveness in nonintubated patients. DESIGN: Prospective, nonrandomized study. SETTING: ICUs at a general and a university hospital. PATIENTS: Nonintubated patients without mechanical ventilation (n = 90) presenting with sepsis-induced acute circulatory failure and considered for volume expansion. INTERVENTIONS: We assessed hemodynamic status at baseline and after a volume expansion induced by a 30-minute infusion of 500-mL gelatin 4%. MEASUREMENTS AND MAIN RESULTS: We measured stroke volume index and collapsibility index of the inferior vena cava under a deep standardized inspiration using transthoracic echocardiography. Vena cava pertinent diameters were measured 15-20 mm caudal to the hepatic vein junction and recorded by bidimensional imaging on a subcostal long-axis view. Standardized respiratory cycles consisted of a deep standardized inspiration followed by passive exhalation. The collapsibility index expressed in percentage equaled the ratio of the difference between end-expiratory and minimum-inspiratory diameter over the end-expiratory diameter. After volume expansion, a relevant (≥ 10%) stroke volume index increase was recorded in 56% patients. In receiver operating characteristic analysis, the area under curve for that collapsibility index was 0.89 (95% CI, 0.82-0.97). When such index is superior or equal to 48%, fluid responsiveness is predicted with a sensitivity of 84% and a specificity of 90%. CONCLUSIONS: The collapsibility index of the inferior vena cava during a deep standardized inspiration is a simple, noninvasive bedside predictor of fluid responsiveness in nonintubated patients with sepsis-related acute circulatory failure.

Macrophage migration inhibitory factor induces contractile and mitochondria dysfunction by altering cytoskeleton network in the human heart.

OBJECTIVES: Macrophage migration inhibitory factor (MIF) has been recognized as a potent proinflammatory mediator that may induce myocardial dysfunction. Mechanisms by which MIF affects cardiac function are not completely elucidated; yet, some macrophage migration inhibitory effects have been related to changes in cytoskeleton architecture. We hypothesized that MIF-induced myocardial dysfunction and mitochondrial respiration deficit could be related to cardiac cell microtubule dynamics alterations. DESIGN: Prospective, randomized study. SETTING: Experimental Cardiovascular Laboratory, University Hospital. SUBJECTS: Human myocardial (atrial) trabeculae. INTERVENTIONS: Atrial trabeculae were obtained at the time of cardiac surgery. Isometrically contracting isolated human right atrial trabeculae were exposed to MIF (100 ng/mL) for 60 minutes, in the presence or not of pretreatment with colchicine (10 µM), a microtubule-depolymerizing agent, or paclitaxel (10 µM) a microtubule-stabilizing agent. MEASUREMENTS AND MAIN RESULTS: Maximal active isometric tension curve and developed isometric force were studied. Trabeculae were then permeabilized for mitochondrial respiration studies using high-resolution oxygraphy. Heart fiber electron microscopy and visualization of ßIV tubulin and polymerized actin by confocal microscopy were used to evaluate sarcomere and microtubule disarray. Compared with controls, MIF elicited cardiac contractile and mitochondrial dysfunction, which were largely prevented by pretreatment with colchicine, but not by paclitaxel. Pretreatment with colchicine prevented MIF-induced microtubule network disorganization, excessive tubulin polymerization, and mitochondrial fragmentation. Compound-C, an inhibitor of AMP-activated protein kinase (AMPK), partially prevented contractile dysfunction, suggesting that cardiac deleterious effects of MIF were related to AMPK activation. CONCLUSIONS: MIF depresses human myocardial contractile function and impairs mitochondrial respiration. Changes in microtubule network likely promote MIF-induced cardiac dysfunction by 1) altering with mitochondrial tubular assembly and outer membrane permeability for adenine nucleotides leading to energy deficit, 2) excessive tubulin polymerization that may impede cardiomyocyte viscosity and motion, and 3) interfering with AMPK pathway.

Efficiency of a pneumatic device in controlling cuff pressure of polyurethane-cuffed tracheal tubes: a randomized controlled study.

BACKGROUND: The primary objective of this study was to determine the efficiency of a pneumatic device in controlling cuff pressure (Pcuff) in patients intubated with polyurethane-cuffed tracheal tubes. Secondary objectives were to determine the impact of continuous control of Pcuff, and cuff shape on microaspiration of gastric contents. METHODS: Prospective randomized controlled study. All patients requiring intubation and mechanical ventilation ≥48 h were eligible. The first 32 patients were intubated with tapered polyurethane-cuffed, and the 32 following patients were intubated with cylindrical polyurethane-cuffed tracheal tubes. Patients randomly received 24 h of continuous control of Pcuff using a pneumatic device (Nosten®), and 24 h of routine care of Pcuff using a manometer. Target Pcuff was 25 cmH2O. Pcuff was continuously recorded, and pepsin was quantitatively measured in all tracheal aspirates during these periods. RESULTS: The pneumatic device was efficient in controlling Pcuff (med [IQ] 26 [24, 28] vs 22 [20, 28] cmH2O, during continuous control of Pcuff and routine care, respectively; p = 0.017). In addition, percentage of patients with underinflation (31% vs 68%) or overinflation (53% vs 100%) of tracheal cuff, and percentage of time spent with underinflation (0.9 [0, 17] vs 14% [4, 30]) or overinflation (0 [0, 2] vs 32% [9, 54]) were significantly (p < 0.001) reduced during continuous control of Pcuff compared with routine care.No significant difference was found in microaspiration of gastric content between continuous control of Pcuff compared with routine care, or between patients intubated with tapered compared with cylindrical polyurethane-cuffed tracheal tubes. CONCLUSION: The pneumatic device was efficient in controlling Pcuff in critically ill patients intubated with polyurethane-cuffed tracheal tubes. TRIAL REGISTRATION: The Australian New Zealand Clinical Trials Registry (NCT01351259).

Continuous control of tracheal cuff pressure and microaspiration of gastric contents in critically ill patients.

RATIONALE: Underinflation of the tracheal cuff frequently occurs in critically ill patients and represents a risk factor for microaspiration of contaminated oropharyngeal secretions and gastric contents that plays a major role in the pathogenesis of ventilator-associated pneumonia (VAP). OBJECTIVES: To determine the impact of continuous control of tracheal cuff pressure (P(cuff)) on microaspiration of gastric contents. METHODS: Prospective randomized controlled trial performed in a single medical intensive care unit. A total of 122 patients expected to receive mechanical ventilation for at least 48 hours through a tracheal tube were randomized to receive continuous control of P(cuff) using a pneumatic device (intervention group, n = 61) or routine care of P(cuff) (control group, n = 61). MEASUREMENTS AND MAIN RESULTS: The primary outcome was microaspiration of gastric contents as defined by the presence of pepsin at a significant level in tracheal secretions collected during the 48 hours after randomization. Secondary outcomes included incidence of VAP, tracheobronchial bacterial concentration, and tracheal ischemic lesions. The pneumatic device was efficient in controlling P(cuff). Pepsin was measured in 1,205 tracheal aspirates. Percentage of patients with abundant microaspiration (18 vs. 46%; P = 0.002; OR [95% confidence interval], 0.25 [0.11-0.59]), bacterial concentration in tracheal aspirates (mean ± SD 1.6 ± 2.4 vs. 3.1 ± 3.7 log(10) cfu/ml, P = 0.014), and VAP rate (9.8 vs. 26.2%; P = 0.032; 0.30 [0.11-0.84]) were significantly lower in the intervention group compared with the control group. However, no significant difference was found in tracheal ischemia score between the two groups. CONCLUSIONS: Continuous control of P(cuff) is associated with significantly decreased microaspiration of gastric contents in critically ill patients.

Passive leg raising is predictive of fluid responsiveness in spontaneously breathing patients with severe sepsis or acute pancreatitis.

OBJECTIVE: Rapid fluid loading is standard treatment for hypovolemia. Because volume expansion does not always improve hemodynamic status, predictive parameters of fluid responsiveness are needed. Passive leg raising is a reversible maneuver that mimics rapid volume expansion. Passive leg raising-induced changes in stroke volume and its surrogates are reliable predictive indices of volume expansion responsiveness for mechanically ventilated patients. We hypothesized that the hemodynamic response to passive leg raising indicates fluid responsiveness in nonintubated patients without mechanical ventilation. DESIGN: Prospective study. SETTING: Intensive care unit of a general hospital. PATIENTS: We investigated consecutive nonintubated patients, without mechanical ventilation, considered for volume expansion. INTERVENTIONS: We assessed hemodynamic status at baseline, after passive leg raising, and after volume expansion (500 mL 6% hydroxyethyl starch infusion over 30 mins). MEASUREMENTS AND MAIN RESULTS: We measured stroke volume using transthoracic echocardiography, radial pulse pressure using an arterial catheter, and peak velocity of femoral artery flow using continuous Doppler. We calculated changes in stroke volume, pulse pressure, and velocity of femoral artery flow induced by passive leg raising (respectively, Deltastroke volume, Deltapulse pressure, and Deltavelocity of femoral artery flow). Among 34 patients included in this study, 14 had a stroke volume increase of >or=15% after volume expansion (responders). All patients included in the study had severe sepsis (n = 28; 82%) or acute pancreatitis (n = 6; 18%). The Deltastroke volume >or=10% predicted fluid responsiveness with sensitivity of 86% and specificity of 90%. The Deltapulse pressure >or=9% predicted fluid responsiveness with sensitivity of 79% and specificity of 85%. The Deltavelocity of femoral artery flow >or=8% predicted fluid responsiveness with sensitivity of 86% and specificity of 80%. CONCLUSIONS: Changes in stroke volume, radial pulse pressure, and peak velocity of femoral artery flow induced by passive leg raising are accurate and interchangeable indices for predicting fluid responsiveness in nonintubated patients with severe sepsis or acute pancreatitis.

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 discuss 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.

[An alternative method to describe an "obesogenic" environment for children: Relevance of a multiple correspondence analysis (MCA) (corrected)]. / Une méthode alternative pour caractériser l'environnement "obésogénique" de l'enfant: Pertinence d'une analyse factorielle des correspondances multiples (AFCM). [corrected]

The purpose of this study was to describe an "obesogenic" environment for a group of schoolchildren using a multiple correspondence analysis (MCA) as an alternative approach to traditional methodological choices. MCA is applicable even for small samples. Ninety-one children (39 girls and 52 boys) aged 10.0 +/- 0.9 years were randomly recruited from two French public schools. Data on their family context, parental involvement, television time and their eating habits were obtained through questionnaires. Their level of physical activity and sedentary time were assessed using an accelerometer (MTI Actigraph model 7164) for three days, including a holiday. The data were processed using an MCA together with a technique for estimating relative risks (RRs) of overweight/obesity according to the distribution of children in the factorial plane produced by the MCA. The "obesogenic" factors appeared as four possible combinations between family environments and various behaviours with regard to physical activity, sedentary behaviour and diet. The RR of overweight/obesity was 2.64 [1.52, 4.57] (P < 0.0001) for a combined association of a "disadvantaged" family environment + low physical activity and high fat diet. The RR of overweight/obesity was 0.36 [0.14, 0.94] (P < 0.05) for an association of a "privileged" family environment + high physical activity and low fat diet. Thus, MCA appears sufficiently robust and relevant to effectively guide etiological hypotheses and decisions about individual and collective intervention strategies.

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.

Actigraph-defined moderate-to-vigorous physical activity cut-off points among children: statistical and biobehavioural relevance.

AIM: To compare Actigraph-defined moderate-to-vigorous physical activity (MVPA) cutpoints among children, combining statistical and biobehavioural analyses. METHODS: One hundred and thirteen children aged 10.0 +/- 0.8 years wore accelerometer for three days. The time they spent in MVPA was estimated using 10 thresholds ranged from 3000 to 3900 cpm. A statistical construct including 45 Bland and Altman pairwise analyses was used to compare the 10 estimates of MVPA. A regression was performed to develop an equation relating mean differences to the between-cutpoint gaps. RESULTS: Mean differences in the MVPA estimates ranged from 1.6 to 12.8 min as a function of increment. Raw estimates of MVPA decreased according to an arithmetic sequence with a common difference of 200 cpm. This difference translates into a drop of 12% in MVPA and a misclassification of up to 5% of children. Mean differences (Y) could be predicted from increments (X) using: Y= 0.02 X (R(2)= 0.99, SEE = 0.72, p < 0.0001). CONCLUSION: When a lack of agreement should be assumed as the between-cutpoint gap exceeds 200 cpm, statistical differences may occur earlier at 90 cpm. Yet, the current equation makes it possible to compare and adjust results from studies/interventions using diverse cutpoints for MVPA among children.

Variations in endotracheal cuff pressure in intubated critically ill patients: prevalence and risk factors.

BACKGROUND AND OBJECTIVE: An endotracheal cuff pressure of 20-30 cmH(2)O is recommended. Underinflation and overinflation are associated with complications such as aspiration and tracheal wall damage. The aim of this study was to identify prevalence of, and risk factors for, endotracheal cuff underinflation and overinflation. METHODS: Prospective observational cohort study. All critically ill patients intubated with a high-volume lowpressure endotracheal tube were eligible. After manual adjustment of cuff pressure at 25 cmH(2)O, continuous recording of cuff pressure and airway pressure was performed for 8 h. Underinflation and overinflation of the endotracheal cuff were defined as cuff pressure less than 20 cmH(2)O and more than 30 cmH(2)O, respectively. In all patients, the time spent with normal cuff pressure or with underinflation or overinflation of the endotracheal cuff was measured. Univariate and multivariate analyses were used to determine risk factors for cuff underinflation and overinflation. RESULTS: Eight hundred and eight hours of cuff pressure recordings were analysed in 101 patients. Eighteen per cent of study patients spent 100% of recording time with normal (20-30 cmH(2)O) cuff pressure. Fifty-four per cent of study patients developed cuff underinflation, 73% developed cuff overinflation, and 44% developed both. Thirty- three per cent of study patients developed underinflation or overinflation for more than 30 min. Absence of sedation [odds ratio (95% confidence interval)=2.51 (1-6), P=0.03] and duration of prior intubation [1.16 (1.04-1.29), P<0.01] were independently associated with cuff underinflation. No risk factor for overinflation could be determined. The percentage of time spent with underinflation significantly (P<0.01) increased during the recording period. CONCLUSION: Variations in endotracheal cuff pressure are common in ICU patients. Duration of prior intubation and absence of sedation are independently associated with increased risk for cuff underinflation.

Antimicrobial treatment for ventilator-associated tracheobronchitis: a randomized, controlled, multicenter study.

INTRODUCTION: Ventilator-associated tracheobronchitis (VAT) is associated with increased duration of mechanical ventilation. We hypothesized that, in patients with VAT, antibiotic treatment would be associated with reduced duration of mechanical ventilation. METHODS: We conducted a prospective, randomized, controlled, unblinded, multicenter study. Patients were randomly assigned (1:1) to receive or not receive intravenous antibiotics for 8 days. Patients with ventilator-associated pneumonia (VAP) prior to VAT and those with severe immunosuppression were not eligible. The trial was stopped early because a planned interim analysis found a significant difference in intensive care unit (ICU) mortality. RESULTS: Fifty-eight patients were randomly assigned. Patient characteristics were similar in the antibiotic (n = 22) and no antibiotic (n = 36) groups. Pseudomonas aeruginosa was identified in 32% of VAT episodes. Although no difference was found in mechanical ventilation duration and length of ICU stay, mechanical ventilation-free days were significantly higher (median [interquartile range], 12 [8 to 24] versus 2 [0 to 6] days, P < 0.001) in the antibiotic group than in the no antibiotic group. In addition, subsequent VAP (13% versus 47%, P = 0.011, odds ratio [OR] 0.17, 95% confidence interval [CI] 0.04 to 0.70) and ICU mortality (18% versus 47%, P = 0.047, OR 0.24, 95% CI 0.07 to 0.88) rates were significantly lower in the antibiotic group than in the no antibiotic group. Similar results were found after exclusion of patients with do-not-resuscitate orders and those randomly assigned to the no antibiotic group but who received antibiotics for infections other than VAT or subsequent VAP. CONCLUSION: In patients with VAT, antimicrobial treatment is associated with a greater number of days free of mechanical ventilation and lower rates of VAP and ICU mortality. However, antibiotic treatment has no significant impact on total duration of mechanical ventilation. TRIAL REGISTRATION: ClinicalTrials.gov, number NCT00122057.

Factors predicting bacterial involvement in severe acute exacerbations of chronic obstructive pulmonary disease.

BACKGROUND: Strategies aiming at reducing antibiotic use are required in the intensive care unit (ICU). Although antibiotic treatment is recommended in patients with severe exacerbation of chronic obstructive pulmonary disease (COPD), a bacterial etiology is found in only a half of these patients. OBJECTIVES: The aim of this study was to determine factors predicting bacterial isolation in severe acute exacerbations of COPD. METHODS: All patients with severe acute exacerbation of COPD requiring intubation and mechanical ventilation were included in this prospective observational cohort study. At ICU admission, information on endotracheal aspirate purulence and hyperthermia was collected. In all patients, Gram stain and quantitative endotracheal aspirate culture (positive at 10(6) cfu/ml) were performed. In addition, leukocyte count, C-reactive protein and procalcitonin (PCT) levels were measured. RESULTS: Ninety-eight severe acute exacerbations of COPD requiring intubation and mechanical ventilation were studied. Forty-nine bacteria were isolated at significant threshold in 40 exacerbations. Streptococcus pneumoniae (16%), methicillin-sensitive Staphylococcus aureus (16%) and Hemophilus influenzae (14%) were the most frequently isolated bacteria. PCT >0.5 ng/ml and positive Gram stain of endotracheal aspirate were independently associated with bacterial isolation in severe acute exacerbation of COPD. Positive Gram stain and PCT >0.5 ng/ml had a negative predictive value >95%. Similar results were found after excluding patients with prior antibiotic treatment. CONCLUSION: Positive Gram stain of endotracheal aspirate and PCT >0.5 ng/ml are independently associated with bacterial isolation in severe acute exacerbation of COPD. These results could be helpful for future interventional studies aiming at reducing antibiotic use in these patients.

Can dynamic indicators help the prediction of fluid responsiveness in spontaneously breathing critically ill patients?

OBJECTIVE: To investigate whether the respiratory changes in arterial pulse (DeltaPP) and in systolic pressure (DeltaSP) could predict fluid responsiveness in spontaneously breathing (SB) patients. Because changes in intrathoracic pressure during spontaneous breathing (SB) might be insufficient to modify loading conditions of the ventricles, performances of indicators were also assessed during a forced respiratory maneuver. DESIGN: Prospective interventional study. SETTING: A 34-bed university hospital medico-surgical ICU. PATIENTS AND PARTICIPANTS: Thirty-two SB patients with clinical signs of hemodynamic instability. INTERVENTION: A 500-ml volume expansion (VE). MEASUREMENTS AND RESULTS: Cardiac index, assessed using transthoracic echocardiography, increased by at least 15% after VE in 19 patients (responders). At baseline, only dynamic indicators were higher in responders than in nonresponders (13+/-5% vs. 7+/-3%, p=0.003 for DeltaPP and 10+/-4% vs. 6+/-2%, p=0.002 for DeltaSP). Moreover, they significantly decreased after VE (11+/-5% to 6+/-4%, p<0.001 for DeltaPP and 8+/-4% to 6+/-3%, p<0.001 for DeltaSP). DeltaPP and DeltaSP areas under the ROC curve were high (0.81+/-0.08 and 0.82+/-0.08; p=0.888, respectively). A DeltaPP>or=12% predicted fluid responsiveness with high specificity (92%) but poor sensitivity (63%). The forced respiratory maneuver reproducing a dyspneic state decreased the predictive power. CONCLUSIONS: Due to their lack of sensitivity and their dependence to respiratory status, DeltaPP and DeltaSP are clearly less reliable to predict fluid responsiveness during SB than in mechanically ventilated patients. However, when their baseline value is high without acute right ventricular dysfunction in a participating patient, a positive response to fluid is likely.

Impact of antifungal treatment on Candida-Pseudomonas interaction: a preliminary retrospective case-control study.

OBJECTIVE: A pathogenic interaction between Candida albicans and Pseudomonas aeruginosa has recently been demonstrated. In addition, experimental and clinical studies identified Candida spp. tracheobronchial colonization as a risk factor for P. aeruginosa pneumonia. The aim of this study was to determine the impact of antifungal treatment on ventilator-associated pneumonia (VAP) or tracheobronchial colonization due to P. aeruginosa. DESIGN AND SETTING: Retrospective observational case-control study conducted in a 30-bed ICU during a 1-year period. PATIENTS AND METHODS: One hundred and two patients intubated and ventilated for longer than 48 h with tracheobronchial colonization by Candida spp. Routine screening for Candida spp. and P. aeruginosa was performed at ICU admission and weekly. Antifungal treatment was based on medical staff decisions. Patients with P. aeruginosa VAP or tracheobronchial colonization were matched (1:2) with patients without P. aeruginosa VAP or tracheobronchial colonization. In case and control patients, risk factors for P. aeruginosa VAP or tracheobronchial colonization were determined using univariate and multivariate analyses. RESULTS: Thirty-six patients (35%) received antifungal treatment. Nineteen patients (18%) developed a P. aeruginosa VAP or tracheobronchial colonization, and all were successfully matched. Antifungal treatment [31% vs 60%; p=0.037, OR (95% CI)=0.67 (0.45-0.90)], and duration of antifungal treatment (7+/-11 vs 14+/-14 days; p=0.045, in case and control patients respectively) were significantly associated with reduced risk for P. aeruginosa VAP or tracheobronchial colonization. Antifungal treatment was the only variable independently associated with P. aeruginosa VAP or tracheobronchial colonization (OR=0.68, 95% CI=0.49-0.90, p=0.046). CONCLUSION: In patients with Candida spp. tracheobronchial colonization, antifungal treatment may be associated with reduced risk for P. aeruginosa VAP or tracheobronchial colonization.

Methodological approach for the evaluation of the performances of medical intensive care units.

PURPOSE: The purpose of the study was to present a methodological approach enabling the comparison of clinical and economic performances of intensive care units and a graphical visualization based on these 2 dimensions. PATIENTS AND METHODS: A retrospective analysis of a database of 666 patients admitted in intensive care units over a period of 2 consecutive months. RESULTS: Calculation of clinical performance is based on the difference between the mortality observed and forecast from the Simplified Acute Physiology Score version 2. The evaluation of resource consumption is carried out from the measure of medical and paramedical care workload. These 2 scores are modeled on the basis of the length of stay and the severity state of the patient. The economic performance is calculated on the basis of the difference between the resource consumption observed and forecast. The graphs are constructed by taking up as coordinates the values of the clinical and economic performances of each center. CONCLUSION: These graphs enable the identification of the most deviating intensive care units to study, for example, their organizational, technical, or human resource setup accounting for their position.

Intensive care unit-acquired Stenotrophomonas maltophilia: incidence, risk factors, and outcome.

INTRODUCTION: The aim of this study was to determine incidence, risk factors, and impact on outcome of intensive care unit (ICU)-acquired Stenotrophomonas maltophilia. METHODS: This prospective observational case-control study, which was a part of a cohort study, was conducted in a 30-bed ICU during a three year period. All immunocompetent patients hospitalised >48 hours were eligible. Patients with non-fermenting Gram-negative bacilli (NF-GNB) at ICU admission were excluded. Patients without ICU-acquired S. maltophilia who developed an ICU-acquired NF-GNB other than S. maltophilia were also excluded. Screening (tracheal aspirate and skin, anal, and nasal swabs) for NF-GNB was performed in all patients at ICU admission and weekly. Univariate and multivariate analyses were performed to determine risk factors for ICU-acquired S. maltophilia and for ICU mortality. RESULTS: Thirty-eight (2%) patients developed an S. maltophilia ICU-acquired colonisation and/or infection and were all successfully matched with 76 controls. Chronic obstructive pulmonary disease (COPD) and duration of antibiotic treatment (odds ratio [OR] [95% confidence interval (CI)] = 9.4 [3 to 29], p < 0.001, and 1.4 [1 to 2.3], p = 0.001, respectively) were independently associated with ICU-acquired S. maltophilia. Mortality rate (60% versus 40%, OR [95% CI] = 1.3 [1 to 1.7, p = 0.037]), duration of mechanical ventilation (23 +/- 16 versus 7 +/- 11 days, p < 0.001), and duration of ICU stay (29 +/- 21 versus 15 +/- 17 days, p < 0.001) were significantly higher in cases than in controls. In addition, ICU-acquired infection related to S. maltophilia was independently associated with ICU mortality (OR [95% CI] = 2.8 [1 to 7.7], p = 0.044). CONCLUSION: COPD and duration of antibiotic treatment are independent risk factors for ICU-acquired S. maltophilia. ICU-acquired S. maltophilia is associated with increased morbidity and mortality rates. ICU-acquired infection related to S. maltophilia is an independent risk factor for ICU mortality.

Gentle blood aspiration and tube cushioning reduce pneumatic tube system interference in lactate dehydrogenase assays.

BACKGROUND: Use of a hospital pneumatic tube system may be associated with measurement errors. METHODS: A venous blood sample was collected from 79 patients into a pair of lithium heparin tubes; one tube was sent to the laboratory by porter and the other was sent via the pneumatic tube system. Plasma lactate dehydrogenase concentrations were then assayed. RESULTS: Lactate dehydrogenase concentrations were overestimated (median bias: 18.8%) when evacuated vacuum lithium heparin tubes were sent by pneumatic tube system. This bias was reduced by bubble-wrapping the standard lithium heparin tube or using Monovette lithium heparin tubes in aspiration mode (median bias: +8.7% and -0.3%, respectively). CONCLUSIONS: Cushioning and aspiration-mode sampling may limit pneumatic tube system-associated overestimation of lactate dehydrogenase concentrations.

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 ventilator-associated pneumonia on outcome in patients with COPD.

PURPOSES: The aim of this study was to determine the impact of ventilator-associated pneumonia (VAP) on outcome in patients with COPD. METHODS: Prospective, observational, case-control study conducted in a 30-bed ICU during a 5-year period. All COPD patients who required intubation and mechanical ventilation (MV) for > 48 h were eligible. VAP diagnosis was based on clinical, radiographic, and quantitative microbiologic criteria. Patients with unconfirmed VAP were excluded, as well as patients with ventilator-associated tracheobronchitis without subsequent VAP. Matching (1:1) criteria included MV duration before VAP occurrence, age +/- 5 years, simplified acute physiology score II on ICU admission +/- 5, and ICU admission category. Variables associated with ICU mortality were determined using univariate and multivariate analyses. RESULTS: A total of 1,241 patients were eligible; 181 patients (14%) were excluded, including 133 patients for VAT and 48 patients for unconfirmed VAP. VAP developed in 77 patients (6%), and all were successfully matched. Pseudomonas aeruginosa was the most frequently isolated bacteria (31%). ICU mortality rate (64% vs 28%), duration of MV (24 +/- 15 d vs 13 +/- 11 d [+/- SD]), and ICU stay (26 +/- 17 d vs 15 +/- 13 d) were significantly (< 0.001) higher in case patients than in control patients. VAP was the only variable independently associated with ICU mortality (odds ratio [OR], 7.7; 95% confidence interval [CI], 3.2 to 18.6; p < 0.001). In VAP patients who received corticosteroids during their ICU stay compared with those who did not receive corticosteroids, mortality rate (50% vs 82%; OR, 1.8; 95% CI, 1.2 to 2.7; p = 0.002), duration of MV (21 +/- 14 d vs 27 +/- 16 d, p = 0.043), and ICU stay (22 +/- 16 d vs 31 +/- 18 d, p = 0.006) were significantly lower. CONCLUSION: VAP is associated with increased mortality rates and longer duration of MV and ICU stay in COPD patients.

Effect of ventilator-associated tracheobronchitis on outcome in patients without chronic respiratory failure: a case-control study.

INTRODUCTION: Our objective was to determine the effect of ventilator-associated tracheobronchitis (VAT) on outcome in patients without chronic respiratory failure. METHODS: This was a retrospective observational matched study, conducted in a 30-bed intensive care unit (ICU). All immunocompetent, nontrauma, ventilated patients without chronic respiratory failure admitted over a 6.5-year period were included. Data were collected prospectively. Patients with nosocomial pneumonia, either before or after VAT, were excluded. Only first episodes of VAT occurring more than 48 hours after initiation of mechanical ventilation were studied. Six criteria were used to match cases with controls, including duration of mechanical ventilation before VAT. Cases were compared with controls using McNemar's test and Wilcoxon signed-rank test for qualitative and quantitative variables, respectively. Variables associated with a duration of mechanical ventilation longer than median were identified using univariate and multivariate analyses. RESULTS: Using the six criteria, it was possible to match 55 (87%) of the VAT patients (cases) with non-VAT patients (controls). Pseudomonas aeruginosa was the most frequently isolated bacteria (34%). Although mortality rates were similar between cases and controls (29% versus 36%; P = 0.29), the median duration of mechanical ventilation (17 days [range 3-95 days] versus 8 [3-61 days]; P < 0.001) and ICU stay (24 days [range 5-95 days] versus 12 [4-74] days; P < 0.001) were longer in cases than in controls. Renal failure (odds ratio [OR] = 4.9, 95% confidence interval [CI] = 1.6-14.6; P = 0.004), tracheostomy (OR = 4, 95% CI = 1.1-14.5; P = 0.032), and VAT (OR = 3.5, 95% CI = 1.5-8.3; P = 0.004) were independently associated with duration of mechanical ventilation longer than median. CONCLUSION: VAT is associated with longer durations of mechanical ventilation and ICU stay in patients not suffering from chronic respiratory failure.