Ward Design in Relation to Postoperative Wound Infection: Part III

The wound infection rates, nasal carriage rates, and nasal colonization rates were studied in a recently built surgical unit for two years when it was first opened. Five years later a further two-year period of study was undertaken.Judging by the incidence of postoperative wound infection, as far as both Staphylococcus pyogenes and Gram-negative organisms are concerned, there is no evidence that the environment has become less safe with use over the seven-year period since opening.     

Ward Design in Relation to Postoperative Wound Infection: Part II

A detailed investigation has been carried out into the behaviour of wounds after 1,000 general surgical operations, about equal numbers of patients having been studied in two different ward and operating theatre environments. The wound sepsis rate was reduced after transfer to the new type of ward. It is concluded that features of the new ward environment were responsible for the observed fall in the incidence of cross-infection.     

Problem Concepts in Evolution Part I: Purpose and Design

In 1999, Scott suggested that evolution has existential repercussions for some students because they confuse methodological naturalism with philosophical naturalism: conflating the incapacity of scientific explanations to appeal to the supernatural with the idea that God must not exist. Unfortunately, part of the reason for the confusion involves terms that are used in a technical sense by evolutionary biologists but that also convey existential meanings to the general public. Such terms therefore should be used carefully by teachers, and their scientific meanings distinguished from their common meanings. We revisit these problem concepts, particularly in light of recent papers in cognitive psychology as they relate to understanding evolution, in a two-part series of articles. Here, in part I, we address design and purpose.     

Sternal Wound Infection after Cardiac Surgery: Management and Outcome

Background

Sternal Wound Infection (SWI) is a severe complication after cardiac surgery. Debridement associated with primary closure using Redon drains (RD) is an effective treatment, but data on RD management and antibiotic treatment are scarce.

Methods

We performed a single-center analysis of consecutive patients who were re-operated for SWI between 01/2009 and 12/2012. All patients underwent a closed drainage with RD (CDRD). Patients with endocarditis or those who died within the first 45 days were excluded from management analysis. RD fluid was cultured twice weekly. Variables recorded were clinical and biological data at SWI diagnosis, severity of SWI based on criteria for mediastinitis as defined by the Centers for Disease Control (CDC), antibiotic therapy, RD management and patient’s outcome.

Results

160 patients developed SWI, 102 (64%) fulfilled CDC criteria (CDC+) and 58 (36%) did not (CDC- SWI). Initial antibiotic treatment and surgical management were similar in CDC+ and CDC- SWI. Patients with CDC+ SWI had a longer duration of antibiotic therapy and a mortality rate of 17% as compared to 3% in patients with CDC- SWI (p = 0.025). Rates of superinfection (10% and 9%) and need for second reoperation (12% and 17%) were similar. Failure (death or need for another reoperation) was associated with female gender, higher EuroScore for prediction of operative mortality, and stay in the ICU.

Conclusion

In patients with SWI, initial one-stage surgical debridement with CDRD is associated with favorable outcomes. CDC+ and CDC- SWI received essentially the same management, but CDC+ SWI has a more severe outcome.     

Effects of Hydrogen Peroxide on Wound Healing in Mice in Relation to Oxidative Damage

It has been established that low concentrations of hydrogen peroxide (H₂O₂) are produced in wounds and is required for optimal healing. Yet at the same time, there is evidence that excessive oxidative damage is correlated with poor-healing wounds. In this paper, we seek to determine whether topical application of H₂O₂ can modulate wound healing and if its effects are related to oxidative damage. Using a C57BL/6 mice excision wound model, H₂O₂ was found to enhance angiogenesis and wound closure at 10 mM but retarded wound closure at 166 mM. The delay in closure was also associated with decreased connective tissue formation, increased MMP-8 and persistent neutrophil infiltration. Wounding was found to increase oxidative lipid damage, as measured by F₂-isoprostanes, and nitrative protein damage, as measured by 3-nitrotyrosine. However H₂O₂ treatment did not significantly increase oxidative and nitrative damage even at concentrations that delay wound healing. Hence the detrimental effects of H₂O₂ may not involve oxidative damage to the target molecules studied.     

Lactobacillus plantarum USM8613 Aids in Wound Healing and Suppresses Staphylococcus aureus Infection at Wound Sites

Probiotics and Antimicrobial Proteins - This study aimed to elucidate the targets and mechanisms of anti-staphylococcal effects from bioactive metabolites produced by lactic acid bacteria. We aimed...