Association of private isolation rooms with ventilator-associated Acinetobacter baumanii pneumonia in a surgical intensive-care unit.

OBJECTIVE: To determine the rates and routes of Acinetobacter baumanii colonization and pneumonia among ventilated patients in a surgical intensive-care unit (SICU) before and after architectural modifications. DESIGN: A nonsequential study comparing two groups of patients. All isolates from systematic and clinical samples were genotyped by pulsed-field gel electrophoresis (PFGE). Records of patients hospitalized during the first and second periods were reviewed and findings were compared. Between the two periods, the SICU was remodeled from enclosed isolation rooms and open rooms to only enclosed isolation rooms with handwashing facilities in each room. SETTING AND PATIENTS: All patients hospitalized and mechanically ventilated for more than 48 hours in the 15-bed SICU of the University Hospital of Besançon (France). RESULTS: For the first and second periods, the rates of colonization were, respectively, 28.1% and 5.0% of patients (P < 10(-7); relative risk [RR], 2.23; 95% confidence interval [CI95], 1.8-2.75) and the specific rates of bronchopulmonary (BP) colonization were, respectively, 9.1 and 0.5 per 1,000 days of mechanical ventilation (P < 10(-5). Seven major PFGE isolate types were identified, 4 of which were isolated from 44 of the 47 colonized or infected patients. Logistic regression analysis showed that colonization was not associated with patient characteristics. CONCLUSION: Conversion from open rooms to isolation rooms may help control nosocomial BP tract acquisition of A baumanii in mechanically ventilated patients hospitalized in an SICU.

Epidemiological study of variations in beta-lactam antibiotic susceptibility of Pseudomonas aeruginosa in two intensive care units.

A six-month prospective study was carried out in the medical and surgical intensive care units (ICUs) at Besançon University Hospital to assess the frequency and risk factors for beta-lactam-resistant isolates of Pseudomonas aeruginosa. Clinical samples were screened for P. aeruginosa, and four antibiograms were distinguished using imipenem and ceftazidime, namely: fully susceptible (SS), imipenem-resistant (RS), ceftazidime-resistant (SR), and resistant to both (RR). DraI restriction fragment length polymorphism of isolates from different patients or with different resistance patterns but the same serotype was assessed by pulsed-field gel electrophoresis. One hundred and twenty-one isolates were obtained from 50 of 281 patients, 60.3% were fully susceptible. 19.8% imipenem-resistant, 13.2% ceftazidime-resistant, and 6.6% resistant to both. Antibiotic-resistance was independent of serotype. Twenty-two of 32 imipenem-resistant isolates from six patients were of the same DNA type, and six other isolates from four patients were of a second DNA type. On only one occasion did a clonally defined strain develop imipenem resistance. By contrast ceftazidime-resistant strains had differing DNA types, but had been originally ceftazidime-susceptible in seven of 12 patients. Reversion of imipenem resistant strains to susceptibility occurred in one patient, and of ceftazidime-resistant strains in five patients. Case-control studies identified prior antibiotic therapy as a risk factor in colonization with resistant strains. Resistance to imipenem followed imipenem therapy, and resistance to ceftazidime followed use of weakly anti-pseudomonal beta-lactam antibiotics. The major route of spread of imipenem-resistant strains was cross-colonization. Thus, assuming appropriate isolation, a carbapenem should be preferred to an extended-spectrum cephalosporin to treat pseudomonas infections in ICU patients.

Interference by hydroxyethyl starch used for vascular filling in latex agglutination test for cryptococcal antigen.

The glucuronoxylomannan component of the Cryptococcus neoformans capsular polysaccharide confers serotype specificity, and its detection in cerebrospinal fluid or serum by the latex agglutination test is used for diagnosis. Low-molecular-weight hydroxyethyl starches can be used as an alternative to albumin for vascular filling. This study reports the occurrence of a false-positive result with the Pastorex Cryptococcus test (Sanofi Diagnostics Pasteur, Marnes la Coquette, France) for a patient receiving hydroxyethyl starch characterized by a substitution ratio of 0.6 (Elohes, Biosedra, Sèvres, France).

[Calorimetric study of enteral low-carbohydrate diet in patients with respiratory insufficiency and decompensation]. / Etude calorimétrique d'un mélange nutritif hypoglucidique entéral chez des patients insuffisants respiratoires au décours de la décompensation.

Standard artificial feeding is not suitable for patients with acute respiratory failure due to the increase in CO2 production it entails, effect of carbohydrate metabolism. Randomized use of an enteral diet comprising 55% of fats in 10 patients with chronic pulmonary disease during an acute phase, receiving mechanical ventilatory support, achieved a rapid decrease of VCO2 value, 243 to 215 ml.min-1, while it increased to 250 ml.min-1 with the control diet. These variations are metabolic and not ventilatory in origin for they are not accompanied by changes in plasmatic total CO2 rate.

[Filter circuits and pollution]. / Circuits filtres et pollution.

The contamination of air of a 50 m3 operating room has been analyzed after three and half hours of halothane enaesthesia with a closed circle system and an opened system. The analysis has been made by gaz chromatography. Concentrations of Halothane found during the use of an opened system are 100 to 120 times the allowable norms in U.S.A. After using the closed circle system, the analysis of air does not reveale any trace of Halothane.