General Anesthesia Alters the Diversity and Composition of the Intestinal Microbiota in Mice.

Dysbiosis of the intestinal microbiota has been shown to result in altered immune responses and increased susceptibility to infection; as such, the state of the intestinal microbiome may have profound implications in the perioperative setting. In this first-in-class study, we used 16s ribosomal RNA sequencing and analysis in a mouse model of general anesthesia to investigate the effects of volatile anesthetics on the diversity and composition of the intestinal microbiome. After 4-hour exposure to isoflurane, we observed a decrease in bacterial diversity. Taxonomic alterations included depletion of several commensal bacteria including Clostridiales. These data identify volatile anesthetics as potential contributors to microbial dysbiosis in the postoperative patient.

Learning from defects to enhance morbidity and mortality conferences.

While required by the Accreditation Council for Graduate Medical Education (ACGME) and recommended by the Institute of Medicine, there are few published studies demonstrating that morbidity and mortality conferences (MMCs) are an effective strategy to improve patient care. To learn from medical incidents and improve patient care, care-givers need to: (1) elicit input from all staff involved in the incident, (2) use a structured framework to investigate all underlying contributing factors, and (3) assign responsibility for management and follow-up on recommendations. Many MMCs lack these key elements. The specific aims of this article are to describe the use of the learning from a defect tool as a strategy to meet ACGME requirements, advance medical education, and enhance traditional MMCs in one fellowship program at an academic medical institution. In addition, this approach improved patient care and provided a foundation for our fellows to use to address patient safety defects after fellowship.

An outbreak of Pseudomonas aeruginosa infections associated with flexible bronchoscopes.

BACKGROUND: Endoscopes, including bronchoscopes, are the medical devices most frequently associated with outbreaks of nosocomial infections. We investigated an outbreak of Pseudomonas aeruginosa infections after bronchoscopic procedures. METHODS: Microbiologic results were reviewed to determine the rates of recovery of P. aeruginosa from bronchoalveolar-lavage specimens. Environmental samples from endoscopes and the endoscopy suite were cultured. Medical records were reviewed to identify infections in the 14 days after a bronchoscopy. RESULTS: The rate of recovery of P. aeruginosa from bronchoalveolar-lavage specimens obtained with use of endoscopy-suite bronchoscopes increased from 10.4 percent at base line to 31.0 percent during the outbreak (relative risk, 2.97; 95 percent confidence interval, 2.28 to 3.90). Cultures of samples from three bronchoscopes grew P. aeruginosa, whereas cultures of samples from the environment, instrument-cleaning machines, and gastrointestinal endoscopes did not. The three bronchoscopes had been part of a nationwide recall. A total of 414 patients underwent bronchoscopy during the outbreak, and there were 48 respiratory tract and bloodstream infections among 39 of these patients (9.4 percent). In 32 infections (66.7 percent), P. aeruginosa was confirmed as a potentially causative organism. Exposure to a potentially contaminated bronchoscope may have had a role in the death of three patients. The rate of recovery of P. aeruginosa returned to base line after the instruments were removed from service. CONCLUSIONS: This large outbreak of P. aeruginosa infections related to bronchoscopy was apparently caused by a loose biopsy-port cap in the bronchoscopes. Instrument safety and surveillance methods for bronchoscopy must be improved, and better recall procedures are needed for medical devices.

Approved Glycopeptide Antibacterial Drugs: Mechanism of Action and Resistance.

The glycopeptide antimicrobials are a group of natural product and semisynthetic glycosylated peptides that show antibacterial activity against Gram-positive organisms through inhibition of cell-wall synthesis. This is achieved primarily through binding to the d-alanyl-d-alanine terminus of the lipid II bacterial cell-wall precursor, preventing cross-linking of the peptidoglycan layer. Vancomycin is the foundational member of the class, showing both clinical longevity and a still preferential role in the therapy of methicillin-resistant Staphylococcus aureus and of susceptible Enterococcus spp. Newer lipoglycopeptide derivatives (telavancin, dalbavancin, and oritavancin) were designed in a targeted fashion to increase antibacterial activity, in some cases through secondary mechanisms of action. Resistance to the glycopeptides emerged in delayed fashion and occurs via a spectrum of chromosome- and plasmid-associated elements that lead to structural alteration of the bacterial cell-wall precursor substrates.