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.

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.

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.

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).

Adverse events during intrahospital transport of critically ill patients: incidence and risk factors.

BACKGROUND: Transport of critically ill patients for diagnostic or therapeutic procedures is at risk of complications. Adverse events during transport are common and may have significant consequences for the patient. The objective of the study was to collect prospectively adverse events that occurred during intrahospital transports of critically ill patients and to determine their risk factors. METHODS: This prospective, observational study of intrahospital transport of consecutively admitted patients with mechanical ventilation was conducted in a 38-bed intensive care unit in a university hospital from May 2009 to March 2010. RESULTS: Of 262 transports observed (184 patients), 120 (45.8%) were associated with adverse events. Risk factors were ventilation with positive end-expiratory pressure >6 cmH2O, sedation before transport, and fluid loading for intrahospital transports. Within these intrahospital transports with adverse events, 68 (26% of all intrahospital transports) were associated with an adverse event affecting the patient. Identified risk factors were: positive end-expiratory pressure >6 cmH2O, and treatment modification before transport. In 44 cases (16.8% of all intrahospital transports), adverse event was considered serious for the patient. In our study, adverse events did not statistically increase ventilator-associated pneumonia, time spent on mechanical ventilation, or length of stay in the intensive care unit. CONCLUSIONS: This study confirms that the intrahospital transports of critically ill patients leads to a significant number of adverse events. Although in our study adverse events have not had major consequences on the patient stay, efforts should be made to decrease their incidence.

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.

Intubation-related tracheal ischemic lesions: incidence, risk factors, and outcome.

PURPOSE: To determine incidence, risk factors and outcome of tracheal ischemic lesions related to intubation. METHODS: Planned post hoc analysis using patients from a previous randomized controlled study. Fiberoptic tracheoscopy was performed during the 24 h following extubation. In patients with >2 ischemic lesions, ulcer or tracheal rupture, fiberoptic tracheoscopy was repeated 2 weeks after the last extubation. Tracheal ischemic lesions were predefined based on a quantitative score. RESULTS: Ninety-six adult patients were included in this study. Eighty (83 %) patients had at least one tracheal ischemic lesion. Thirty-seven (38 %) patients had a tracheal ischemia score > median score (5; IQ 1, 7). The most common tracheal ischemic lesion was ischemia (68 %), followed by hyperemia (54 %), ulcer (10 %), and tracheal rupture (1 %). Univariate analysis identified duration of neuromuscular-blocking agent use, overinflation of tracheal cuff (>30 cmH2O), percentage of P cuff determination >30 cmH2O, duration of assist-control ventilation, and plateau pressure as risk factors for having a tracheal ischemia score >5. Duration of assist-control mechanical ventilation was the only factor independently associated with tracheal ischemia score >5 [OR (95 % CI) 1.10 per hour (1.02-1.20)]. A fiberoptic tracheoscopy was performed 2 weeks after extubation in 22 patients. This examination was normal in all patients, except the one with tracheal rupture who had marked improvement. CONCLUSION: Tracheal ischemic lesions are common in intubated, critically ill patients. Duration of assist-control mechanical ventilation through a tracheal tube is the only independent risk factor. These lesions healed in the majority of patients 2 weeks after extubation.

Hemodynamic changes during a deep inspiration maneuver predict fluid responsiveness in spontaneously breathing patients.

OBJECTIVE: We hypothesized that the hemodynamic response to a deep inspiration maneuver (DIM) indicates fluid responsiveness in spontaneously breathing (SB) patients. DESIGN: Prospective study. SETTING: ICU of a general hospital. PATIENTS: Consecutive nonintubated patients without mechanical ventilation, considered for volume expansion (VE). INTERVENTION: We assessed hemodynamic status at baseline and after VE. MEASUREMENTS AND MAIN RESULTS: We measured radial pulse pressure (PP) using an arterial catheter and peak velocity of femoral artery flow (VF) using continuous Doppler. Changes in PP and VF induced by a DIM (ΔPPdim and ΔVFdim) were calculated in 23 patients. ΔPPdim and ΔVFdim ≥12% predicted responders to VE with sensitivity of 90% and specificity of 100%. CONCLUSIONS: In a restricted population of SB patients with severe sepsis or acute pancreatitis, ΔPPdim and ΔVFdim are accurate indices for predicting fluid responsiveness. These results should be confirmed in a larger population before validating their use in current practice.

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.

New methods to clean ICU rooms.

Hospital-acquired infections (HAI) represent the most common adverse event in the intensive care unit (ICU). Their prevalence is high and they are associated with increased morbidity and mortality. The environment plays a central role in the transmission of hospital-acquired pathogens (HAP) and in the pathogenesis of HAI. Many bacteria, especially multidrug resistant ones, can survive for several months in the hospital environment in particular in areas close to the patients. It has been proven that pathogens are transmitted from the environment to the patients. Many studies have concluded that current cleaning methods are microbiologically ineffective. This failure concerns daily cleaning as well as terminal cleaning after patient discharge. It has been demonstrated that improvements in environmental cleaning are associated with a decrease in the rate of HAP and of HAI. New cleaning methods could enhance hospital cleaning efficiency. Three new technologies seem promising because they are microbiologically effective, easy and safe to use: (1) hydrogen peroxide vapor and (2) UV light decontamination are used for terminal cleaning. These techniques are effective even in difficultly accessible areas. (3) ultramicrofibers which can be associated with a copper-based biocide can be used for daily cleaning. Other methods such as ozone, steam or high-efficiency particulate air filtration are not efficient enough to be considered serious contenders for the improvement of the quality of the hospital environment. These new technologies have not been yet linked to a decrease in the prevalence and the incidence in HAP and HAI. It remains difficult to justify the extra-cost associated with these new methods until more studies can confirm their effectiveness in the management of HAI.

The impact of COPD on ICU mortality in patients with ventilator-associated pneumonia.

OBJECTIVE: To determine the impact of COPD on intensive care unit (ICU) mortality in patients with VAP. METHODS: This prospective observational study was performed in a mixed ICU during a 3-year period. Eligible patients received mechanical ventilation for >48 h and met criteria for microbiologically confirmed VAP. Risk factors for ICU mortality were determined using univariate and multivariable analyses. RESULTS: Two hundred and fifteen patients with microbiologically confirmed VAP were included. Most VAP episodes were late-onset (88%), and Pseudomonas aeruginosa was the most frequently isolated bacterium (39% of VAP episodes). ICU mortality was significantly lower in non-COPD patients (n = 150) compared to COPD patients (n = 65) (43.3% vs 60%, p = 0.027, OR [95% CI] = 1.96 [1.8-3.54]). Duration (days) of mechanical ventilation and ICU stay median (IQR) in non-COPD patients were 25 (15-42) and 30 (18-48), whereas in COPD patients were 31 (19-45) and 36 (20-48) (p > 0.05). The differences in duration (days) of mechanical ventilation and ICU stay were significant between non-COPD patients and severe COPD (GOLD stage IV) patients (p = 0.001 and p = 0.02, respectively). Multivariable analysis identified COPD [OR (95% CI) 2.58 (1.337-5)], SAPS II [1.024 (1.006-1.024)] and presence of shock at VAP diagnosis [3.72 (1.88-7.39)] as independent risk factors for ICU mortality. CONCLUSION: COPD, SAPS II, and shock at VAP diagnosis are independently associated with ICU mortality in patients who present VAP.

[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.

Impact of polyurethane on variations in tracheal cuff pressure in critically ill patients: a prospective observational study.

OBJECTIVE: To determine the impact of polyurethane (PU) on variations in cuff pressure (P (cuff)) in intubated critically ill patients. METHODS: Prospective observational before-after study performed in a ten-bed ICU. Cuff pressure was continuously recorded for 24 h in 76 intubated patients, including 26 with polyvinyl chloride (PVC), 22 with cylindrical polyurethane (CPU), and 28 with tapered polyurethane (TPU)-cuffed tracheal tubes. P (cuff) was manually adjusted every 8 h by nurses and was maintained around 25 cmH(2)O. Time spent with cuff underinflation and overinflation was continuously measured. In addition, pepsin, a proxy for microaspiration of gastric contents, was quantitatively measured in tracheal secretions at the end of recording period. RESULTS: A total of 1,824 h of continuous recording of cuff pressure was analyzed. Patient characteristics were similar in the three groups. No significant difference was found in percentage of time spent with underinflation (mean +/- SD, 26 +/- 22, 28 +/- 12, 30 +/- 13% in PVC, CPU, and TPU groups, respectively) and overinflation [median (IQR), 7 (2-14), 6 (3-14), 11% (5-20)] among the three groups. However, a significant difference was found in the coefficient of variation of P (cuff) (mean +/- SD, 82 +/- 48, 92 +/- 47, 135 +/- 67, p = 0.002). While the coefficient of P (cuff) variation was significantly (p < 0.017) higher in the TPU compared to CPU and PVC groups, no significant difference was found between the CPU and PVC groups. The pepsin level was significantly different among the three groups (408 +/- 282, 217 +/- 159, 178 +/- 126 ng/ml; p < 0.001). In fact, the pepsin level was significantly lower in the CPU and TPU groups compared with the PVC group. CONCLUSION: PU does not impact variations in P (cuff) in critically ill patients.

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.

Daily serum piperacillin monitoring is advisable in critically ill patients.

The aim of the present study was to evaluate the benefit of monitoring serum piperacillin concentrations in critically ill patients. This was an 11-month, prospective, observational study in a 30-bed Intensive Care Unit in a teaching hospital, involving 24 critically ill patients with evidence of bacterial sepsis. All patients received a 66 mg/kg intravenous bolus of piperacillin in combination with tazobactam (ratio 1:0.125) followed by continuous infusion of 200mg/kg/24h. The dosage was adjusted when the serum piperacillin concentration either fell below 4x the drug's minimum inhibitory concentration (MIC) for the causative agent or exceeded the toxic threshold of 150 mg/L. With the initial regimen, serum piperacillin concentrations were within the therapeutic target range in only 50.0% of patients (n=12). This proportion increased to 75.0% (18 patients) (P=0.006) following dosage adjustment. For patients with low initial serum piperacillin concentrations (n=8), the percentage of time during which the concentration remained above 4x MIC (%T>4x MIC) was 7.1+/-5.9% before dosage adjustment and 27.3+/-8.6% afterwards. In conclusion, in critically ill patients, monitoring and adjustment of serum piperacillin levels is required to prevent overdosing and might also help to correct underdosing, an important cause of antibiotic therapy failure.

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.

How school time physical activity is the "big one" for daily activity among schoolchildren: a semi-experimental approach.

BACKGROUND: This study was designed to model the relationship between an ActiGraph-based "in-school" physical activity (PA) and the daily one among children and to quantify how school can contribute to the daily PA recommendations. METHOD: Fifty boys and 43 girls (aged 8 to 11 years) wore ActiGraph for 2 schooldays of no structured PA. The daily moderate-to-vigorous PA (MVPA(d)) was regressed on the school time MVPA (MVPA(s)). Then, a ROC analysis was computed to define the required MVPA(s). RESULTS: Children spent 57% of their awaking time at school. School time PA opportunities (ie, recesses: approximately 18% of a child's awaking time) accounted for > 70% of the MVPA(d) among children. Then, MVPA(d) (Y) could be predicted from MVPA(s) (X) using the equation: Y= 2.06 X0.88; R2 = .889, P < .0001. Although, this model was sex-specifically determined, cross-validations showed valid estimates of MVPA(d). Finally, with a sensitivity of 100% and a specificity of 90%, MVPA(s), a 34 min x d(-1) was required to prompt the daily recommendation. CONCLUSIONS: The current study shows the contribution of MVPA at school to recommended activity levels and suggests the value of activity performed during recesses. It also calls for encouraging both home- and community-based interventions, predominantly directed toward girls.

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.

Prehospital pain treatment: an economic productivity factor in emergency medicine?

RATIONALE AND OBJECTIVES: Analgesia is a recommended practice for pain treatment in prehospital emergency medicine, but all experts note suboptimal pain relief or oligoanalgesia. The increase in the Care Workload (CW) and the Medical Treatment Duration (MTD) linked to analgesia are two explanatory factors, and they are representative of the unavailability of a prehospital team. The unavailability of a team is an opportunity cost which is probably the most important cost within the framework of prehospital emergency. The aim of this study was to analyse the influence of analgesia use on the availability of prehospital emergency teams. METHODS: This study was a prospective, multicentre cohort study conducted in 10 French Mobile Emergency and Resuscitation Services (MERS) between September 2001 and June 2003. A case-control study was performed including 568 case patients who received analgesia matched with controls based on diagnosis and severity. The pairs were compared for MTD and CW. RESULTS: No significant difference between cases and controls was found concerning MTD (P = 0.134). Conversely, a difference was found for CW (P < 10(-4)), with a mean value of 53.7 Project Recherche Nursing (PRN) points for the cases and 45.8 PRN points for the controls. CONCLUSIONS: This study shows that analgesia generates an additional CW without increasing the MTD, and does not hinder the MERS teams' availability. This economic result should improve adherence to these clinical practice guidelines. Thus, analgesia appears to be a factor of productivity in the current context of economic pressures in terms of the funding of the healthcare system.