Cardiac troponin I as an early prognosis biomarker after trauma: a retrospective cohort study.

BACKGROUND: The significance of cardiac troponin I (cTnI) elevation after trauma is debated. We therefore explored the association between cTnI elevation at admission after trauma and ICU mortality. METHODS: We performed a retrospective analysis from a prospectively constituted database, of patients admitted to ICU after trauma at a single centre, over a 36 month period. According to cTnI plasma concentration at admission, patients were categorised into three groups: normal (<0.05 ng ml-1), intermediate (0.05-0.99 ng ml-1), or high concentration (≥1.0 ng ml-1). Associations of pre-hospital conditions or cTnI elevation and mortality were analysed by multivariate logistic regression. RESULTS: Among the 994 patients, 177 (18%) had cTnI elevation at ICU admission. Of this total, 114 (11%) patients died in the ICU. The cTnI release was an independent predictor of ICU mortality with a concentration-response relationship [odds ratio (OR) 4.90 (2.19-11.16) and 14.83 (4.68-49.90) for intermediate and high concentrations, respectively] and Day 2 mortality [OR 2.23 (1.18-5.80) and 7.49 (2.77-20.12) for intermediate and high concentrations, respectively]. The severity of thoracic trauma [OR 2.25 (1.07-4.55) and 3.23 (2.00-5.27) for Abbreviated Injury Scale scores 1-2 and ≥3, respectively], out-of-hospital maximal heart rate ≥120 beats min-1 [OR 2.22 (1.32-3.69)], and out-of-hospital shock [OR 2.02 (1.20-3.38)] were independently associated with cTnI elevation. CONCLUSIONS: Release of cTnI was an independent predictor of ICU mortality, suggesting that this biomarker can be used in daily practice for early stratification of the risk of ICU death. Thoracic trauma was strongly associated with cTnI elevation.

Performance and impact of a rapid method combining mass spectrometry and direct antimicrobial susceptibility testing on treatment adequacy of patients with ventilator-associated pneumonia.

Inappropriate antibiotic therapy in ventilator-associated pneumonia (VAP) is associated with increased mortality. Using broad-spectrum antibiotics for 48 h until the results of conventional cultures and antimicrobial susceptibility testing (AST) are available, may promote the emergence of drug-resistant bacteria. Performing AST directly on clinical respiratory samples would hasten the process by at least 24 h. Here, we analysed the diagnostic performance of a rapid method combining mass spectrometry and direct AST (DAST), and compared it with the conventional method (mass spectrometry with conventional AST (CAST)). Additionally, we assessed its potential impact on antimicrobial use in patients. Over a period of 18 months, the two methods were performed on 85 bronchoalveolar lavages obtained from intensive care unit patients with suspected VAP, and in which Gram-negative bacilli were observed on direct examination. Only the CAST results were reported to the clinicians. DAST produced useable results in 85.9% of the patients. The sensitivity and negative predictive values of DAST were 100% for all antibiotics tested, except gentamicin (97.1%, (95% CI 93.3-101) and 97.4% (93.7-101), respectively) and amikacin (88.9% (81.7-96.1) and 96.4% (92.1-100.7), respectively), compared with CAST. Specificity and positive predictive values ranged from 82.9 (74.2-91.5) to 100%, and from 86.4 (78.5-94.2) to 100%, respectively. If the DAST results had been reported to the clinicians, treatment could have been optimized 24 h earlier in 35/85 (41.2%) patients, with 17 carbapenem patient-days saved. Overall, routine use of the DAST method could help optimize earlier antibiotic treatment in patients with suspected VAP.

Impact of imipenem and amikacin pharmacokinetic/pharmacodynamic parameters on microbiological outcome of Gram-negative bacilli ventilator-associated pneumonia.

OBJECTIVES: Despite recent advances, antibiotic therapy of ventilator-associated pneumonia (VAP) in ICU patients is still challenging. We assessed the impact of imipenem and amikacin pharmacokinetic and pharmacodynamic parameters on microbiological outcome in these patients. PATIENTS AND METHODS: Patients with Gram-negative bacilli (GNB) VAP were prospectively included. Blood samples for pharmacokinetic analysis were collected after empirical administration of a combination of imipenem three times daily and one single dose of amikacin. MICs were estimated for each GNB obtained from respiratory samples. Microbiological success was defined as a ≥10(3) cfu/mL decrease in bacterial count in quantitative cultures between baseline and the third day of treatment. RESULTS: Thirty-nine patients [median (min-max) age = 60 years (28-84) and median SAPS2 at inclusion = 40 (19-73)] were included. Median MICs of imipenem and amikacin were 0.25 mg/L (0.094-16) and 2 mg/L (1-32), respectively. Median times over MIC and over 5× MIC for imipenem were 100% (8-100) and 74% (3-100), respectively. The median C1/MIC ratio for amikacin was 23 (1-76); 34 patients (87%) achieved a C1/MIC ≥10. Microbiological success occurred in 29 patients (74%). No imipenem pharmacodynamic parameter was significantly associated with the microbiological success. For amikacin, C1/MIC was significantly higher in the microbiological success group: 26 (1-76) versus 11 (3-26) (P = 0.004). CONCLUSIONS: In ICU patients with VAP, classic imipenem pharmacodynamic targets are easily reached with usual dosing regimens. In this context, for amikacin, a higher C1/MIC ratio than previously described might be necessary.

Population pharmacokinetics of single-dose amikacin in critically ill patients with suspected ventilator-associated pneumonia.

AIMS: Modifications of antimicrobials' pharmacokinetic parameters have been reported in critically ill patients, resulting in a risk of treatment failure. We characterized amikacin pharmacokinetic variability in critically ill patients with ventilator-associated pneumonia (VAP) and evaluated several dosing regimens. METHODS: We conducted a prospective multicenter study in critically ill patients with presumptive diagnosis of Gram-negative bacilli (GNB) VAP. Patients empirically received imipenem and a single-dose of amikacin, which was administered as a 30-min infusion (20 mg/kg). Concentrations were measured 0.5, 1, 8, 16, and 24 h after beginning of infusion. Pharmacokinetic parameters were estimated using a population approach. Main pharmacodynamic target was a ratio ≥ 10 between the concentration achieved 1 h after beginning of infusion (C 1h) and the minimal inhibitory concentration of the liable bacteria (MIC). We simulated individual C 1h for several dosing regimens by Monte Carlo method and computed C 1h/MIC ratios for MICs from 0.5 to 64 mg/L. RESULTS: Sixty patients (47 males), median (range) age, and body weight, 61.5 years (28-84) and 78 kg (45-126), respectively, were included. Amikacin median C 1h was 45 mg/L (22-87). Mean value (between-patients variability) for CL, V1, Q, and V2 were 4.3 L/h (31 %), 15.9 L (22 %), 12.1 L/h (27 %), and 21.4 L (47 %), respectively. CL increased with CrCL (p<0.001) and V1 with body weight (p<0.001) and PaO2/FIO2 ratio (p<0.001). With a 25 mg/kg regimen, the pharmacodynamic target was achieved in 20 and 96 % for a MICs of 8 and 4 mg/L, respectively. CONCLUSION: Amikacin clearance was decreased and its volume of distribution was increased as previously reported. A ≥ 25 mg/kg single-dose is needed for empirical treatment of GNB-VAP.

Neurological complications of HIV infection in critically ill patients: clinical features and outcomes.

OBJECTIVE: We aimed to investigate the prognosis of HIV-infected patients with acute neurological complications at the highly active antiretroviral therapy (HAART) era. METHODS: We performed a retrospective study in HIV-infected patients admitted to a medical ICU with neurological complications between 2001 and 2008. RESULTS: Among the 210 studied patients (median [interquartile range] CD4-cell count: 80 [18-254]/µL; HIV viral load: 4.8 [2-5.3] log10/mL), 40 (19%) had unknown HIV status at admission. Neurological complications consisted in delirium (45%), coma (39%), seizures (32%) and/or intracranial hypertension (21%). Admission diagnoses were AIDS-defining CNS disease for 88 (42%) patients, non-AIDS-defining CNS disease for 45 (21%), and systemic disease with neurological signs for 77 (37%). Seizures (p=0.003), focal deficit (p<0.001) and intracranial hypertension (p<0.001) were more frequently observed in patients with AIDS-defining CNS disease. Factors independently associated with ICU mortality (29.5%) were intracranial hypertension [odds ratio (OR), 5.09; 95% confidence interval (95% CI), 2.17-11.91], vasopressor use [OR, 3.92; 95% CI, 1.78-8.60] and SAPS II score [per 10-point increment, OR, 1.59; 95% CI, 1.31-1.93]. CONCLUSIONS: Prognosis of HIV-infected patients with neurological complications depends rather on clinical presentation than on HIV-related parameters. Intracranial hypertension symptoms at admission have a major impact on outcome.

Tracheal intubation of morbidly obese patients: LMA CTrach vs direct laryngoscopy.

BACKGROUND: LMA CTrach (CT), a modified version of the intubating LMA Fastrach, allows continuous video-endoscopy of the tracheal intubation procedure. We tested the hypothesis that the CT is efficient for tracheal intubation of morbidly obese patients who are at risk of a difficult airway. METHODS: After Ethics' Committee approval, 104 morbidly obese patients (BMI >35 kg m(-2)) scheduled for bariatric surgery were included in this prospective study. Patients were randomly assigned in two groups: tracheal intubation using direct laryngoscopy (DL) or the CT. Induction of anaesthesia was standardized using sufentanil, propofol and succinylcholine. Characteristics and consequences of airway management were evaluated. RESULTS: Preoperative characteristics of patients and consequences of anaesthesia induction on physiological variables were similar in both groups. Difficulty in facemask ventilation was similar in both groups. Tracheal intubation was successfully carried out with DL and CT. Forty-nine per cent of the patients from the CT group required laryngeal mask manipulation (ventilation and view optimization) resulting in increased duration of tracheal intubation by 57 s as compared with DL. Oxygenation was of better quality in the patients managed with CT than with DL. Blind tracheal intubation was mandatory in eight (17%) patients of the DL group, while tracheal intubation was seen in all patients of the CT group. CONCLUSION: We demonstrated that the CT was an efficient airway device for ventilation and tracheal intubation in case of a difficult airway in morbidly obese patients.