Drainage days-an independent risk factor for serious sternal wound infections after cardiac surgery: a case control study.

BACKGROUND: Postoperative sternal wound infections are a potentially devastating complication following cardiac surgery. The aim of our study was to determine risk factors associated with patients' baseline characteristics and peri- and postoperative management for the development of surgical site infections (SSIs) after cardiac surgery involving sternotomy. METHODS: Since 2009 the University Hospital of Basel, a tertiary care center in Switzerland, has participated in the national SSI-surveillance program by conducting postdischarge surveillance. We conducted a nested case-control study involving 30 consecutive patients with an organ/space SSI after cardiac surgery and 60 control patients. RESULTS: Receipt of antibiotics before operation (odds ratio [OR], 1.20; 95% confidence interval [CI], 1.02-1.41; P = .032), decreased albumin levels (OR, 0.87; 95% CI, 0.76-0.99; P = .040, respectively), time on extracorporal circulation (OR, 1.02; 95% CI, 1.00-1.03; P = .012), number of drainages (OR, 9.15; 95% CI, 2.01-41.76; P = .004), length of drain retention (OR, 1.44; 95% CI, 1.10-1.90; P = .009), and resuscitation (OR, 7.30; 95% CI, 1.53-34.71; P = .012) were associated with SSIs. Incidence density drainage days-accounting for both number of drains and length of retention-were the only independent risk factor (OR, 1.12; 95% CI, 1.02-1.11; P = .018). CONCLUSIONS: Retention of drainages in the operative site longer than 48 hours was the only independent risk factor for the development of organ/space sternal wound infections after cardiac surgery.

A new cable-tie-based sternal closure device: infectious considerations.

OBJECTIVES: To determine the difference in sternal infection and other infectious events between conventional wire and cable-tie-based closure techniques post-sternotomy in a collective of patients after cardiac surgery. METHODS: The sternal ZipFix™ (ZF) system consists of a biocompatible poly-ether-ether-ketone (PEEK) cable-tie that surrounds the sternum through the intercostal space and provides a large implant-to-bone contact. Between 1 February 2011 and 31 January 2012, 680 cardiac operations were performed via sternotomy at our institution. After the exclusion of operations for active endocarditis and early mortality within 7 days, 95 patients were exclusively closed with ZF and could be compared with 498 who were closed with conventional wires (CWs) during the same period. A multivariable logistic regression analysis, including body mass index, renal impairment and emergency as suspected confounders and inverse propensity weights was performed on the infection rate. RESULTS: Total infection rate was 6.1%, with a total of 36 diagnosed sternal infections (5 in ZF and 31 in CW). Comparing ZF with CW with regard to sternal infection, there is no statistically significant difference related to the device (odds ratio: 0.067, confidence interval: 0.04-9.16, P=0.72). The propensity modelling provided excellent overlap and the mean propensity was almost the same in both groups. Thus, we have observed no difference in receiving either ZF or CW. No sternal instability was observed with the ZF device, unlike 4/31 patients in the CW group. The overall operation time is reduced by 11 min in the ZF group with identical perfusion and clamping times. CONCLUSIONS: Our study underlines a neutral effect of the sternal ZipFix™ system in patients regarding sternal infection. Postoperative complications are similar in both sternal closure methods. The cable-tie-based system is fast, easy to use, reliable and safe.

Equal efficacy of glucoprotamin and an aldehyde product for environmental disinfection in a hematologic transplant unit: a prospective crossover trial.

BACKGROUND: The inanimate hospital environment has emerged as an important reservoir of nosocomial pathogens. In particular, multidrug-resistant pathogens, such as methicillin-resistant Staphylococcus aureus, Acinetobacter species, and Clostridium difficile, play a major role in the transmission of hospital-acquired infections. In Europe, aldehydes, chlorine, and quaternary ammonium compounds have been commonly used for environmental disinfection. Glucoprotamin, a newer active compound for disinfectants, has been clinically tested for disinfection of instruments but not for environmental disinfection. OBJECTIVE: This study evaluated the antimicrobial effectiveness of a glucoprotamin-containing product (Incidin) compared with that of an aldehyde-containing product (Deconex), the current standard at our institution. METHODS: This prospective crossover study was conducted in our access-restricted hematologic transplant unit. A total of 3,086 samples from the environment were processed and examined for overall bacterial burden as well as selectively for S. aureus, C. difficile, and gram-negative bacteria. RESULTS: There was no significant difference in residual bacteria after disinfection between the 2 products in terms of overall burden and selected pathogens. Enterococci were the predominant pathogens recovered from surfaces, but no vancomycin-resistant enterococci were recovered. Similarly, C. difficile could not be found in the patients' environment, even in rooms, despite the use of selective media. CONCLUSION: The aldehyde-containing product (Deconex) and the glucoprotamin-containing product (Incidin) demonstrated similar efficacy against environmental contamination in a hematologic transplant unit with the application of selective media for C. difficile, S. aureus, and gram-negative bacteria in addition to standard medium.

Denitratisoma oestradiolicum gen. nov., sp. nov., a 17beta-oestradiol-degrading, denitrifying betaproteobacterium.

A Gram-negative, motile, denitrifying bacterium (strain AcBE2-1(T)) was isolated from activated sludge of a municipal wastewater treatment plant using 17beta-oestradiol (E2) as sole source of carbon and energy. Cells were curved rods, 0.4-0.8 x 0.8-2.0 microm in size, non-fermentative, non-spore-forming, oxidase-positive and catalase-negative. E2 was oxidized completely to carbon dioxide and water by reduction of nitrate to a mixture of dinitrogen monoxide and dinitrogen, with the intermediate accumulation of nitrite. Electron recoveries were between 90 and 100 %, taking assimilated E2 into account. With nitrate as the electron acceptor, the bacterium also grew on fatty acids (C(2) to C(6)), isobutyrate, crotonate, dl-lactate, pyruvate, fumarate and succinate. Phylogenetic analysis of its 16S rRNA gene sequence revealed that strain AcBE2-1(T) represents a separate line of descent within the family Rhodocyclaceae (Betaproteobacteria). The closest relatives are the cholesterol-degrading, denitrifying bacteria Sterolibacterium denitrificans DSM 13999(T) and strain 72Chol (=DSM 12783), with <93.9 % sequence similarity. The G+C content of the DNA was 61.4 mol%. Detection of a quinone system with ubiquinone Q-8 as the predominant compound and a fatty acid profile that included high concentrations of C(16 : 1)omega7c/iso-C(15 : 0) 2-OH and C(16 : 0), in addition to C(18 : 1)omega7c and small amounts of C(8 : 0) 3-OH, supported the results of the phylogenetic analysis. On the basis of 16S rRNA gene sequence data in combination with chemotaxonomic and physiological data, strain AcBE2-1(T) (=DSM 16959(T)=JCM 12830(T)) is placed in a new genus Denitratisoma gen. nov. as the type strain of the type species Denitratisoma oestradiolicum gen. nov., sp. nov.

Thiomicrospira arctica sp. nov. and Thiomicrospira psychrophila sp. nov., psychrophilic, obligately chemolithoautotrophic, sulfur-oxidizing bacteria isolated from marine Arctic sediments.

Two psychrophilic, chemolithoautotrophic, sulfur-oxidizing bacteria were isolated from marine Arctic sediments sampled off the coast of Svalbard with thiosulfate as the electron donor and CO(2) as carbon source. Comparative analysis of 16S rRNA gene sequences suggested that the novel strains, designated SVAL-D(T) and SVAL-E(T), represent members of the genus Thiomicrospira. Further genotypic (DNA-DNA relatedness, DNA G+C content) and phenotypic characterization revealed that the strains represent members of two novel species. Both organisms are obligately autotrophic and strictly aerobic. Nitrate was not used as an electron acceptor. Chemolithoautotrophic growth was observed with thiosulfate, tetrathionate and sulfur. The temperature limits for growth of both strains were between -2 degrees C and 20.8 degrees C, with optima of 11.5-13.2 degrees C (SVAL-E(T)) and 14.6-15.4 degrees C (SVAL-D(T)), which is about 13-15 degrees C lower than the optima of all other recognized Thiomicrospira species. The maximum growth rate on thiosulfate at 14 degrees C was 0.14 h(-1) for strain SVAL-E(T) and 0.2 h(-1) for strain SVAL-D(T). Major fatty acids of SVAL-D(T) are C(16 : 1), C(18 : 0) and C(16 : 0), and those of SVAL-E(T) are C(16 : 1), C(18 : 1), C(16 : 0) and C(14 : 1). Cells of SVAL-D(T) and SVAL-E(T) are rods, like those of their closest relatives. To our knowledge the novel strains are the first psychrophilic, chemolithoautotrophic, sulfur-oxidizing bacteria so far described. The names Thiomicrospira arctica sp. nov. and Thiomicrospira psychrophila sp. nov. are proposed for SVAL-E(T) (=ATCC 700955(T)=DSM 13458(T)) and SVAL-D(T) (=ATCC 700954(T)=DSM 13453(T)), respectively.