Bernard Allaouchiche

Early coagulopathy in trauma patients: An on-scene and hospital admission study

PURPOSE Amongst trauma patients, early coagulopathy is common on hospital admission. No studies have evaluated the initial coagulation status in the pre-hospital setting. We hypothesise that the coagulopathic process begins at the time of trauma. We studied the on-scene and on hospital arrival coagulation profile of trauma patients. METHODS Prospective, observational study investigating the on-scene coagulation profile and its time course. We studied 45 patients at the scene of the accident, before fluid administration, and on hospital admission and classified their coagulopathy using the International Society on Thrombosis and Haemostasis score during a 2-month period. Prothrombin time, activated partial thromboplastin time, fibrinogen concentration, factors II, V and VII activity, fibrin degradation products, antithrombin and protein C activities, platelet counts and base deficit were measured. RESULTS The median injury severity score was 25 (13-35). On-scene, coagulation status was abnormal in 56% of patients. Protein C activities were decreased in the trauma-associated coagulopathy group (p=.02). Drops in protein C activities were associated with changes in activated partial thromboplastin time, prothrombin time, fibrinogen concentration, factor V and antithrombin activities. Only factor V levels decreased significantly with the severity of the trauma. On hospital admission, coagulation status was abnormal in 60% of patients. The on-scene coagulopathy was spontaneously normalised only in 2 patients whereas others had the same or a poorer coagulopathy status. All parameters of coagulation were significantly abnormal comparing to the on-scene phase. Decreases in protein C activities were related to the coagulation status (p<.0001) and changes in other coagulation parameters. Patients with base deficit ≤-6 mmol/L had changes in antithrombin, factor V and protein C activities but no significant coagulopathy. CONCLUSION Coagulopathy occurs very early after injury, before fluid administration, at the site of accident. Coagulation and fibrinolytic systems are activated early. The incidence of coagulopathy is high and its severity is related to the injury and not to hypoperfusion.

Outcomes in severe sepsis and patients with septic shock: pathogen species and infection sites are not associated with mortality.

Objectives:We evaluated the respective influence of the causative pathogen and infection site on hospital mortality from severe sepsis related to community-, hospital-, and intensive care unit-acquired infections. Design:We used a prospective observational cohort 10-yr database. We built a subdistribution hazards model with corrections for competing risks and adjustment for potential confounders including early appropriate antimicrobial therapy. Setting:Twelve intensive care units. Patients:We included 4,006 first episodes of acquisition-site-specific severe sepsis in 3,588 patients. Inteventions:None. Measurements and Main Results:We included 1562 community-acquired, 1432 hospital-acquired, and 1012 intensive care unit-acquired episodes of severe sepsis. After adjustment, we found no independent associations of the causative organism, multidrug resistance of the causative organism, infection site, or presence of bacteremia with mortality. Early appropriate antimicrobial therapy was consistently associated with better survival in the community-acquired (0.64 [0.51–0.8], p = .0001), hospital-acquired (0.72 [0.58–0.88], p = .0011), and intensive care unit-acquired (0.79 [0.64–0.97], p = .0272) groups. Conclusion:The infectious process may not exert as strong a prognostic effect when severity, organ dysfunction and, above all, appropriateness of early antimicrobials are taken into account. Our findings emphasize the importance of developing valid recommendations for early antimicrobial therapy.

Alveolar and Serum procalcitonin. Diagnostic and prognostic value in ventilator-associated pneumonia

Background The potential role of serum and alveolar procalcitonin as early markers of ventilator-associated pneumonia (VAP) and its prognostic value were investigated. Methods Ninety-six patients with a strong suspicion of VAP were prospectively enrolled. VAP diagnosis was based on a positive quantitative culture obtained via a mini–bronchoalveolar lavage of 103 colony-forming units/ml or more. Blood and alveolar samples were collected for procalcitonin measurement and analyzed for diagnostic and prognostic evaluation on days 0, 3, and 6. Sensitivity, specificity, positive likelihood ratio, and receiver-operating characteristic curves were analyzed to define ideal cutoff values and approach the decision analysis. Results Serum procalcitonin was significantly increased in the VAP group (n = 44) compared with the non-VAP group (n = 52): 11.5 ng/ml (95% confidence interval, 5.9–17.0) versus 1.5 ng/ml (1.1–1.9). A serum procalcitonin concentration greater than 3.9 ng/ml (best cutoff value) was considered positive for the VAP diagnosis (sensitivity, 41%; specificity, 100%). Serum procalcitonin was significantly increased in the non-survivors compared with the survivors for the VAP group: 16.5 ng/ml (95% confidence interval, 8.1–24.9) versus 2.9 ng/ml (1.2–4.7). The best cutoff value for serum procalcitonin of the nonsurvivors in the VAP group was 2.6 ng/ml (sensitivity, 74%; specificity, 75%; positive likelihood ratio, 2.96). Regarding VAP diagnosis and prognosis, no significant differences were found for alveolar procalcitonin in all groups. Conclusions Serum but not alveolar procalcitonin seems to be a helpful parameter in the early VAP diagnosis and an appropriate marker for predicting mortality.

Steady-state plasma and intrapulmonary concentrations of cefepime administered in continuous infusion in critically ill patients with severe nosocomial pneumonia.

ObjectiveTo determine the steady-state plasma and epithelial lining fluid concentrations of cefepime administered in continuous infusion in critically ill patients with severe bacterial pneumonia. DesignProspective, open-label study. SettingAn intensive care unit and research ward in a university hospital. PatientsTwenty adult patients with severe nosocomial bacterial pneumonia on mechanical ventilation were enrolled. InterventionsAll subjects received a 30-min intravenous infusion of cefepime 2 g followed by a continuous infusion of 4 g over 24 hrs. The concentrations of cefepime in plasma and epithelial lining fluid were determined at steady state after 48 hrs of therapy with high performance liquid chromatography. Measurements and Main ResultsThe mean ± sd steady-state plasma and epithelial lining fluid concentrations of cefepime 4 g in continuous infusion were 13.5 ± 3.3 &mgr;g/mL and 14.1 ± 2.8 &mgr;g/mL, respectively, with a mean percentage penetration of cefepime into epithelial lining fluid of about 100%. ConclusionsThe administration of 4 g of cefepime in continuous infusion in critically ill patients with severe nosocomial pneumonia appears to optimize the pharmacodynamic profile of this &bgr;-lactam by constantly providing concentrations in excess of minimal inhibitory concentration of most of susceptible organisms over the course of therapy in both serum and epithelial lining fluid.

Clinical Assessment of the Ultrasonographic Measurement of Antral Area for Estimating Preoperative Gastric Content and Volume

BACKGROUND This prospective observational study aimed to assess the feasibility and performance of the ultrasonographic measurement of antral cross-sectional area (CSA) for the preoperative assessment of gastric contents and volume in adult patients and for the diagnosis of risk stomach (defined by the presence of solid particles and/or gastric fluid volume >0.8 ml/kg). METHODS A preoperative ultrasonographic measurement of the antral CSA was performed for each patient by a physician (L.B.) blinded to the history of the patient. Immediately after tracheal intubation, an 18-French multiorifice Salem tube was inserted and gastric contents were aspirated in five different patient positions; during this time, the patients epigastrium was massaged and the tube was moved backward and forward in the stomach. The relationship between the antral area and the volume of aspirated gastric contents was analyzed, as was the performance of ultrasonographic measurement of antral area for the diagnosis of risk stomach. RESULTS The measurement of antral CSA was performed on 180 of 183 patients. A significant positive relationship between antral CSA and aspirated fluid volume was found. The cutoff value of antral CSA of 340 mm(2) for the diagnosis of risk stomach was associated with a sensitivity of 91% and a specificity of 71%. The area under the receiver operating characteristic curve for the diagnosis of risk stomach was 90%. CONCLUSIONS The ultrasonographic measurement of antral CSA could be an important help for the anesthesiologist in minimizing the risk of pulmonary aspiration of gastric contents due to general anesthesia.

Oxidative Stress Status During Exposure to Propofol, Sevoflurane and Desflurane

We evaluated the circulating and lung oxidative status during general anesthesia established with propofol, sevoflurane, or desflurane in mechanically ventilated swines. Blood samples and bronchoalveolar lavage fluid (BAL) specimens were respectively performed via an internal jugular vein catheter and a nonbronchoscopic BAL for baseline oxidative activity measurements: malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPX). A 4-h general anesthesia was then performed in the three groups of 10 swine: the Propofol group received 8 mg · kg−1 · h−1 of IV propofol as the sole anesthetic; the Desflurane group received 1.0 minimum alveolar concentration of desflurane; and the Sevoflurane group received 1.0 minimum alveolar concentration of sevoflurane. We observed significantly larger levels of MDA in plasma and BAL during desflurane exposure than with the other anesthetics. We also observed smaller concentrations of circulating GPX and alveolar GPX. We found a significant decrease for MDA measurements in the plasma and the pulmonary lavage during propofol anesthesia. We also found larger values of GPX measurements in the serum and the pulmonary lavage. No significant changes were observed when animals were exposed to sevoflurane. No significant changes were found for circulating concentrations of SOD during exposure to all anesthetics. In this mechanically ventilated swine model, desflurane seemed to induce a local and systemic oxidative stress, whereas propofol and sevoflurane were more likely to have antioxidant properties.

Early identification of patients at risk for difficult intubation in the intensive care unit: development and validation of the MACOCHA score in a multicenter cohort study.

RATIONALE Difficult intubation in the intensive care unit (ICU) is a challenging issue. OBJECTIVES To develop and validate a simplified score for identifying patients with difficult intubation in the ICU and to report related complications. METHODS Data collected in a prospective multicenter study from 1,000 consecutive intubations from 42 ICUs were used to develop a simplified score of difficult intubation, which was then validated externally in 400 consecutive intubation procedures from 18 other ICUs and internally by bootstrap on 1,000 iterations. MEASUREMENTS AND MAIN RESULTS In multivariate analysis, the main predictors of difficult intubation (incidence = 11.3%) were related to patient (Mallampati score III or IV, obstructive sleep apnea syndrome, reduced mobility of cervical spine, limited mouth opening); pathology (severe hypoxia, coma); and operator (nonanesthesiologist). From the β parameter, a seven-item simplified score (MACOCHA score) was built, with an area under the curve (AUC) of 0.89 (95% confidence interval [CI], 0.85-0.94). In the validation cohort (prevalence of difficult intubation = 8%), the AUC was 0.86 (95% CI, 0.76-0.96), with a sensitivity of 73%, a specificity of 89%, a negative predictive value of 98%, and a positive predictive value of 36%. After internal validation by bootstrap, the AUC was 0.89 (95% CI, 0.86-0.93). Severe life-threatening events (severe hypoxia, collapse, cardiac arrest, or death) occurred in 38% of the 1,000 cases. Patients with difficult intubation (n = 113) had significantly higher severe life-threatening complications than those who had a nondifficult intubation (51% vs. 36%; P < 0.0001). CONCLUSIONS Difficult intubation in the ICU is strongly associated with severe life-threatening complications. A simple score including seven clinical items discriminates difficult and nondifficult intubation in the ICU. Clinical trial registered with www.clinicaltrials.gov (NCT 01532063).

A multicentre observational study of intra‐operative ventilatory management during general anaesthesia: tidal volumes and relation to body weight

We conducted an observational prospective multicenter study to describe the practices of mechanical ventilation, to determine the incidence of use of large intra‐operative tidal volumes (≥ 10 ml.kg−1 of ideal body weight) and to identify patient factors associated with this practice. Of the 2960 patients studied in 97 anaesthesia units from 49 hospitals, volume controlled mode was the most commonly used (85%). The mean (SD) tidal volume was 533 (82) ml; 7.7 (1.3) ml.kg−1 (actual weight) and 8.8 (1.4) ml.kg−1 (ideal body weight)). The lungs of 381 (18%) patients were ventilated with a tidal volume > 10 ml.kg−1 ideal body weight. Being female (OR 5.58 (95% CI 4.20–7.43)) and by logistic regression, underweight (OR 0.06 (95% CI 0.01–0.45)), overweight (OR 1.98 (95% CI 1.49–2.65)), obese (OR 5.02 (95% CI 3.51–7.16)), severely obese (OR 10.12 (95% CI 5.79–17.68)) and morbidly obese (OR 14.49 (95% CI 6.99–30.03)) were the significant (p ≤ 0.005) independent factors for the use of large tidal volumes during anaesthesia.

Association between hypernatraemia acquired in the ICU and mortality: a cohort study

BACKGROUND The aim of this study is to describe the prevalence and outcomes of intensive care unit (ICU)-acquired hypernatraemia (IAH). METHODS A retrospective analysis was performed on a prospectively collected database fed by 12 ICUs. Subjects are unselected patients with ICU stay >48 h. Mild and moderate to severe hypernatraemia were defined as serum sodium >145 and >150 mmol/L, respectively. IAH was hypernatraemia occurring >or=24 h after ICU admission in patients with normal serum sodium at ICU admission. RESULTS Of the 8441 patients, 301 were excluded because they had hypernatraemia at ICU admission. Of the remaining 8140 patients, 901 (11.1%) experienced mild hypernatraemia, and 344 (4.2%) experienced moderate to severe hypernatraemia. Factors independently associated with IAH were male gender, severity at admission as assessed by the Simplified Acute Physiology Score version II (SAPS II), and organ failure or life-supporting treatment at ICU admission. Unadjusted hospital mortality was 15.2% in patients without hypernatraemia compared to 29.5% in patients with mild IAH and 46.2% in those with moderate to severe IAH (P < 0.0001). When any degree of IAH was handled as a time-dependent variable in a subdistribution hazard model, the subdistribution hazard ratio (SHR) for ICU mortality was 4.26 [95% confidence interval (CI), 3.74-4.84]. After stratification by centre and adjustment for confounders, both mild IAH and moderate to severe IAH were independently associated with mortality [SHR 2.03 (95% CI 1.73-2.39) and 2.67 (95% CI 2.19-3.26), respectively]. CONCLUSION IAH is frequent and associated with mortality after adjustment on severity at ICU admission.

Risk factors for airway complications during general anaesthesia in paediatric patients

Summary Background: Although airway complications are a frequent problem during paediatric anaesthesia, no study has prospectively identified risk factors for adverse respiratory events during airway management when LMA™ (laryngeal mask airway), face mask (FM) or a tracheal tube (TT) are used.