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.

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.

Epidemiology and prognostic factors of critically ill patients treated with hemodiafiltration.

PURPOSE: The objective of this study is to study the epidemiology, outcome, and prognostic factors of critically ill patients treated with continuous venovenous hemodiafiltration (CVVHDF). MATERIALS AND METHODS: Observational cohort was done in a French 16-bed intensive care unit (ICU) from a university-affiliated urban hospital. All patients requiring, in the opinion of the treating physician, the initiation of CVVHDF were included in the study. RESULTS: One hundred ninety-seven patients with acute renal failure (ARF) treated with CVVHDF were studied. The incidence of ARF treated with CVVHDF was 5.9% in the ICU with a mortality rate of 71.6%. A multivariate analysis identified 3 independent factors associated with fatal outcome: mechanical ventilation, sepsis, and septic shock requiring vasoactive drug. In contrast, 2 independent factors predicted a favorable outcome: nonoliguric ARF and serum creatinine concentration higher than 34 mg/L at CVVHDF initiation. A flowchart determined by the chi2 Automatic Interaction and Detection statistical method allowed for the identification of patients' subgroups with different mortality rates ranging from 25% to 100%. CONCLUSIONS: In our series, ARF treated with CVVHDF was associated with a high overall ICU mortality rate (71.6%). However, our prognostic flowchart identified patients with low mortality rates for which renal replacement therapy must be initiated with no discussion as soon as required.

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.

Physical activity and sedentary lifestyle in children as time-limited functions: usefulness of the principal component analysis method.

This study was designed to examine the hourly variation in and the interplay between physical activity and sedentary behavior (SB) in order to highlight key time periods for physical activity interventions for children. Data for physical activity and SB obtained with ActiGraph in 56 boys and 47 girls aged from 8 to 11 years. These data were divided into sixty minute-time samples for moderate-to-vigorous physical activity (MVPA) and SB, and analyzed using a principal component analysis (PCA) and correlation statistics. The PCA provides 10 factors which account for 80.4% of the inertia. Only two of these factors did not display competition between MVPA and SB. Contrary to some reports, a coefficient of correlation of -.68 (p < 10(-4)) was found between daily time spent at MVPA and SB. Some salient traits of children's behaviors were shown through PCA. The results suggested that efficacy of interventions targeting the morning hours (07:00 AM-11:59 AM) and the afternoon period (02:00 PM-05:59 PM) warrants attention.

Moderate-to-vigorous physical activity among children: discrepancies in accelerometry-based cut-off points.

OBJECTIVE: To highlight the discrepancies in accelerometry cut-off points of moderate-to-vigorous physical activity (MVPA) according to the definitions of Puyau et al. (MVPA(P)) and Trost et al. (MVPA(T)). RESEARCH METHODS AND PROCEDURES: Forty-five children from 8 to 11 years old were monitored with the ActiGraph (ActiGraph, LLC, Fort Walton Beach, FL) for 3 consecutive days. Daily time spent at MVPA obtained with MVPA(P) was compared with that obtained with MVPA(T) using variability, regression, and agreement statistics. Data were then discussed with regard to physical activity recommendations. RESULTS: The mean daily time spent at MVPA(P) (28 +/- 18 minutes) was significantly lower (p < 10(-4)) than that spent at MVPA(T) (141 +/- 39 minutes). The coefficient of determination between the two definitions was low (R(2) = 0.49 +/- 0.71). There was a lack of agreement between the two definitions, with a mean error or bias of 113 min/d. Thirty-four point eight percent and 100% of children underwent 30-minute MVPA/d with MVPA(P) and MVPA(T) definitions, respectively. DISCUSSION: Comparability between studies devoted to describing children's physical activity or to assessing interventions may lack consistency according to the definition, with a real risk of misclassification.

Multiple-drug-resistant bacteria in patients with severe acute exacerbation of chronic obstructive pulmonary disease: Prevalence, risk factors, and outcome.

OBJECTIVE: To determine prevalence, risk factors, and effect on outcome of multiple-drug-resistant (MDR) bacteria in patients with severe acute exacerbation of chronic obstructive pulmonary disease. DESIGN: Prospective, observational, cohort study. SETTING: Thirty-bed medical intensive care unit (ICU) in a university hospital. METHODS: All chronic obstructive pulmonary disease patients with acute exacerbation who required intubation and mechanical ventilation for >48 hrs were eligible during a 4-yr period. Patients with pneumonia or other causes of acute respiratory failure were not eligible. In all patients, quantitative tracheal aspirate was performed at ICU admission (positive at 10 colony-forming units [cfu]/mL). MDR bacteria were defined as methicillin-resistant Staphylococcus aureus, ceftazidime- or imipenem-resistant Pseudomonas aeruginosa, Acinetobacter baumannii, Stenotrophomonas maltophilia, and extended-spectrum beta-lactamase-producing Gram-negative bacilli. All patients received empirical antibiotic treatment at ICU admission. Univariate and multivariate analyses were used to determine variables associated with MDR bacteria and variables associated with ICU mortality. RESULTS: A total of 857 patients were included, and 304 bacteria were isolated (>/=10 cfu/mL) in 260 patients (30%), including 75 MDR bacteria (24%) in 69 patients (8%). When patients with MDR bacteria were compared with patients without MDR bacteria, previous antimicrobial treatment (odds ratio [OR], 2.4; 95% confidence interval [95% CI], 1.2-4.7; p = .013) and previous intubation (OR, 31; 95% CI, 12-82; p < .001) were independently associated with MDR bacteria. When patients with bacteria other than MDR or patients with no bacteria were used as a reference group, these risk factors were still independently associated with MDR bacteria. Although ICU mortality rate was higher in patients with MDR bacteria than in patients without MDR bacteria (44% vs. 25%; p = .001; OR, 2.3; 95% CI, 1.4-3.8), MDR bacteria were not independently associated with ICU mortality. Inappropriate initial antibiotic treatment (88% vs. 5%; p = <.001; OR, 6.7; 95% CI, 3.8-12) and ventilator-associated pneumonia (23% vs. 5%; p = <.001; OR, 1.3; 95% CI, 1-1.8) rates were significantly higher in patients with MDR bacteria than in patients with bacteria other than MDR. Inappropriate initial antibiotic treatment was independently associated with increased ICU mortality (OR, 7.1; 95% CI, 1.9-30; p = .003). CONCLUSION: MDR bacteria are common in patients with acute exacerbation of chronic obstructive pulmonary disease requiring intubation and mechanical ventilation. Previous antimicrobial treatment and previous intubation are independent risk factors for MDR bacteria. Although MDR bacteria are not independently associated with ICU mortality, inappropriate initial antibiotic treatment is an independent risk factor for ICU mortality in these patients. Further studies are needed to determine whether broad-spectrum antibiotic treatment is cost-effective in these patients.

First-generation fluoroquinolone use and subsequent emergence of multiple drug-resistant bacteria in the intensive care unit.

OBJECTIVE: The objective of this study was to determine the relationship between fluoroquinolone (FQ) use and subsequent emergence of multiple drug-resistant bacteria (MRB) in the intensive care unit (ICU). DESIGN: The authors conducted a prospective observational cohort study and a case control study. SETTING: The study was conducted in a 30-bed ICU. METHODS: All immunocompetent patients hospitalized for >48 hrs who did not receive antibiotics before ICU admission were eligible during a 15-month period. Routine MRB screening was performed at ICU admission and weekly thereafter. This screening included tracheal aspirate and nasal, anal, and axilla swabs. Univariate and multivariate analyses were used to determine risk factors for MRB emergence in the ICU. In addition, a case control study was performed to determine whether FQ use is associated with subsequent emergence of MRB. RESULTS: Two hundred thirty-nine patients were included; 108 ICU-acquired MRB were isolated in 77 patients. FQ use and longer duration of antibiotic treatment were identified as independent risk factors for MRB occurrence (odds ratio [95% confidence interval [CI] = 3.3 [1.7-6.5], 1.1 [1.0-1.2]; p < .001; respectively). One hundred thirty-five (56%) patients received FQ; matching was successful for 72 (53%) of them. Number of MRB (40 vs. 15 per 1,000 ICU days; p = .019) and percentage of patients with MRB (40% vs. 22%; OR [95% CI] = 1.5 [1.0-2.4]; p = .028) were significantly higher in cases than in controls. Although methicillin-resistant Staphylococcus aureus (26% vs. 12%; OR [95% CI] = 1.6 [.6-2.9]; p = .028) and extending-spectrum beta-lactamase-producing Gram-negative bacilli (11% vs. 1%; OR [95% CI] = 4.7 [0.7-30.2]; p = .017) rates were higher in cases than in controls, ceftazidime or imipenem-resistant Pseudomonas aeruginosa (15% vs. 8%), Acinetobacter baumannii (1% vs. 5%), and Stenotrophomonas maltophilia (2% vs. 1%) rates were similar (p > .05) in case and control patients. CONCLUSION: FQ use and longer duration of antibiotic treatment are independently associated with MRB emergence. Reducing antimicrobial treatment duration and restricting FQ use could be suggested to control MRB spread in the ICU.

Hospital-acquired pneumonia: risk factors, clinical features, management, and antibiotic resistance.

PURPOSE OF REVIEW: The aim of this review is to summarize recent developments regarding risks factors, clinical features, management and antimicrobial resistance, and prevention of hospital-acquired pneumonia. RECENT FINDINGS: Risk factors for hospital-acquired pneumonia developing in specific ICUs (neurologic and cardiovascular surgery) were reported. Characteristics of pneumonia acquired in general wards but requiring ICU admission were studied. Analysis of the impact of reintubation on pneumonia occurrence demonstrated that only reintubation after accidental extubation increases the risk. Early administration of adequate antibiotic(s), associated with a deescalating strategy, remains the only measure directly amenable to modification by clinicians that decreases the infection-related mortality. Numerous data emphasized the recommendation that guidelines for hospital-acquired pneumonia therapy should be updated and customized to local patterns to improve the level of adequacy of antimicrobial treatment. A 8-day treatment regimen could be proposed when pneumonia is not caused by a nonfermenting, gram-negative bacilli. In cases of pneumonia caused by methicillin-resistant Staphylococcus aureus, linezolid, compared with vancomycin, significantly increases the rates of cure and survival. Semirecumbent positioning in all eligible patients, sucralfate rather than H2 antagonists in patients at low to moderate risk of gastrointestinal bleeding, and, in selected patients, aspiration of subglottic secretions and oscillating beds are the measures proposed to prevent the development of ventilator-associated pneumonia. Conversely, the routine or indiscriminate use of selective digestive decontamination is not recommended. SUMMARY: In our opinion, the optimization of the length of treatment and the reduction of mortality with linezolid in staphylococcal pneumonia are two major recent developments.