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The paper presents results concerning the sustainability of laundering processes which were achieved by BMBF research projects of the wfk Cleaning Technology Research Institute on reduction of energy and detergent in professional laundries (01 RT 9973) and by the development of economical laundering processes with optimised water-, energy- and detergent consumption to achieve an appropriate particle content for operating theatre textiles (0330466). General reduction of water and energy consumption was reached by optimisation of mechanical agitation in tunnel washers (continuous batch washers). Investigations in laundries showed significant increase of soil removal by rotating drum in comparison to oscillation drum systems with consequence of reduced dosage of detergents. This is especially for soil which is mainly removed by mechanical action. At the same time no higher values of textile damage occurred. In addition, the total water consumption was reduced to 4 L/kg. In research project 0330466 economical washing processes were developed with appropriate particle release for surgical textiles (drapes, gowns, clean air suits). The investigations were carried out with respect to textile material and its making up, washing and rinsing technology, drying technology as well as detergents and laundry aids. By use of suitable textiles, optimisation of laundering and drying processing, application of suitable detergents and installation of an online-particle control system in the tumble dryer, the specific water consumption was reduced from about 40 L/kg to 20 L/kg. In addition, the detergent dosage was reduced to 60%.

A wide range of test methods are used worldwide for testing the performance of laundry detergents. Principally, all methods need tracer stains. Uniformly stained standard tracer stains are occasionally considered ‘artificial’ while manually prepared or circular stains are at the same time accepted as ‘natural’. This distinction is not helpful, it is even incorrect. Uniformly stained tracer stains were developed to improve reproducibility. Only few existing stains are additionally heat treated or represent combinations of several stain substances ((effect stains)). All tests are supposed to provide performance results reflecting reality (i. e. consumer perception); suitability of any of the model systems depends solely on their ability to provide results for reliable performance assessment. Extensive comparative tests using different stain systems confirmed that preparation of small batches using different fabric substrates, finish and pre-treatment is beneficial for testing e. g. soil release polymer performance. Apart from that, uniformly soiled standard stains in general showed better reproducibility while providing comparable performance results. We could confirm that standard stains are a good solution for addressing issues with dissatisfactory reproducibility.

The distributions of radiolabelled free cefoxitin (FC) and liposome-encapsulated cefoxitin (LC) were compared in an animal model of intra-abdominal sepsis. Intraperitoneally administered LC was initially retained in the peritoneal cavity with subsequent preferential drug targeting to the liver (14% injected LC) and spleen (6% injected LC) by 3 h post-injection. Differing patterns of liposomal drug and lipid retention indicated that drug release from the liposome complex occurred within the peritoneum, liver and spleen. Intraperitoneal FC was rapidly taken up into the systemic circulation, with peak recovery in the blood (9% injected FC) and liver (5% injected FC) at 1 h post-injection. FC was also rapidly eliminated; 7% of the injected drug was recovered in the kidney 1 h post-injection. A negligible amount of FC was recovered in the spleen and very little FC or LC was found in the lungs of treated animals. Unlike FC, LC was found to provide a sustained bactericidal drug level (> 40 μg mL−1) in the peritoneal fluid for up to 5 h post-injection. LC also achieved significantly higher drug levels, compared with FC, within the liver at 3 and 5 h post-injection. Since severe intra-abdominal sepsis is often characterized by the presence of intraphagocytic bacteria in hepatic and splenic reticuloendothelial systems, the enhanced delivery of liposome-encapsulated anti-microbial agents, such as cefoxitin, to the liver and spleen may provide a more effective treatment for the septic condition.

OBJECTIVE: To test the hypothesis that comprehensive broad-spectrum empirical antimicrobial therapy is superior to limited-spectrum empirical antimicrobial therapy in intra-abdominal infections. DESIGN: Prospective, randomized, double-blinded study. SETTING: University-affiliated hospitals in Canada. PATIENTS: Two hundred thirteen patients with intra-abdominal infections and planned operative or percutaneous drainage. INTERVENTION: Limited-spectrum empirical antimicrobial therapy consisted of cefoxitin sodium, 2 g, intravenously, every 6 hours (n=109). Comprehensive broad-spectrum empirical antimicrobial therapy consisted of a combination of imipenem and cilastatin sodium, 500 mg, intravenously, every 6 hours (n=104). MAIN OUTCOME MEASURES: Failure to cure the intra-abdominal infection (persistence of infection or death). RESULTS: Of initial isolates, 98% were sensitive to imipenem plus cilastin sodium compared with 72% for cefoxitin. No difference was found in the failure rate between treatment groups. Among various reasons for failure (including technical), 12 of 80 patients in the limited-spectrum empirical antimicrobial therapy group had resistant organisms at a second intervention compared with 1 of 74 in the comprehensive broad-spectrum empirical antimicrobial therapy group (P<.003, χ2). One death in the limited-spectrum empirical antimicrobial therapy group was due to autopsy-proved disseminated Pseudomonas aeruginosa (blood, peritoneum, lung, and pleural fluid) that was resistant to cefoxitin, and the other was associated with peritonitis due to cefoxitin-resistant Enterobacter cloacae. One death in the comprehensive broad-spectrum empirical antimicrobial therapy group was associated with peritonitis from Clostridium perfringens that was sensitive to imipenem plus cilastin sodium, and the other was associated with peritonitis from Pseudomonas aeruginosa that was resistant to imipenem plus cilastin sodium. CONCLUSION: Treatment failure of intra-abdominal infection may be due, in part, to the presence of resistant pathogens at the site of infection. Therefore, routine culture of these sites seems worthwhile and empirical therapy should be as comprehensive as possible and should cover all potential pathogens.Arch Surg. 1996;131:1193-1201

Liposomal encapsulation of antimicrobial agents has been used to improve drug delivery, particularly against intracellular pathogens. The effect of unilamellar liposomes on macrophage activation in response to Escherichia coli lipopolysaccharide was examined. Liposomes caused a dose- and time-dependent inhibition of tumor necrosis factor release by lipopolysaccharide-treated cells. The accumulation of tumor necrosis factor mRNA transcripts was unaffected, suggesting a posttranscriptional mechanism for this effect. However, induction of macrophage procoagulant activity was unaffected by liposomes, indicating a selective rather than a global inhibition. These data suggest that liposomes used for drug delivery may modulate the host response to infection.

Antral biopsy specimens from patients with acid peptic disease were cultured in parallel on Skirrow medium (SM) and sheep blood agar (SBA) for Campylobacter pylori. In institution 1, 23 of 88 (26.1%) endoscopies were positive on SBA compared with 37 of 88 (42.0%) on SM (P = 0.0001). In institution 2, 29 of 49 (59.2%) endoscopies were positive for C. pylori on SBA and 27 of 49 (55.1%) were positive on SM (P = 0.50). The addition of SM optimizes the recovery of C. pylori from antral biopsy specimens.