Postoperative nausea and vomiting in bariatric surgery in comparison to non-bariatric gastric surgery.

INTRODUCTION: Postoperative nausea and vomiting (PONV) are complications of general anesthesia. Patient-specific factors, type of surgery and a variety of drugs determine the frequency. Clinical experience shows nausea and vomiting to be very frequent in morbidly obese patients undergoing bariatric surgery. AIM: To detect the onset and extent of nausea and vomiting in the group of morbidly obese patients undergoing laparoscopic bariatric surgery. MATERIAL AND METHODS: We conducted a retrospective data bank analysis (since 2004) of all patients with body mass index > 35 kg/m2 undergoing laparoscopic bariatric surgery in comparison to patients with a body mass index < 35 kg/m2 undergoing gastric surgery. Propensity score matching was applied to minimize bias effects. The frequency of postoperative nausea was defined as the primary outcome parameter. RESULTS: One hundred and thirty-eight patients were included. There was a significant difference between the morbidly obese group and the control group concerning the frequency of postoperative nausea (15.9% vs. 55.1%; p < 0.001). In patients receiving volatile anesthetics a significant difference between groups concerning frequency of PONV was not observed. Intravenous anesthetics were suitable to reduce PONV in the control group but not in the morbidly obese group (12.5% vs. 56.8%, p < 0.001). With given prophylaxis PONV events still occurred in 15.6% vs. 48.8% (p = 0.003). CONCLUSIONS: Morbidly obese patients undergoing laparoscopic bariatric surgery are at higher risk of suffering from PONV than non-morbidly obese patients. To reduce the PONV incidence in morbidly obese patients, further research, especially focusing on more efficient use of antiemetic drugs, seems to be necessary.

The influence of body mass index on temperature management during general anaesthesia-A prospective observational study.

RATIONALE, AIMS, AND OBJECTIVES: During general anaesthesia, body core temperature is influenced by several factors that are either anaesthesia-related (type and duration of anaesthesia and fluid management), surgery-related (type of surgery and extent of the surgical procedure), or patient-related (age, gender, body weight, and preoperative body core temperature). Interestingly, data concerning body mass index (BMI) and its influence on patients' temperature are sparse. The aim of this study was to evaluate the impact of BMI on body core temperature under general anaesthesia. METHODS: A single centre, prospective, observational study was conducted at a university hospital. Two cohorts (lower limb surgery and abdominal surgery) were evaluated. Patients were treated according to actual German guidelines for the prevention of hypothermia. Temperature was measured sublingually prior to anaesthesia and during the first 60 minutes of anaesthesia. Each cohort was divided in three subgroups (BMI < 24 kg m-2 , BMI 25-34.9 kg m-2 , and BMI > 35 kg m-2 ) according to body weight. RESULTS: A total of 206 patients were evaluated. One hundred four underwent lower limb surgery; 102 underwent abdominal surgery. After induction of anaesthesia, temperature dropped in all subgroups, but this decline was more pronounced in patients with lower BMI. Significant differences concerning temperature changes were observed in abdominal surgery between low and high BMI groups. After 60 minutes of anaesthesia, group-dependent temperature differences had levelled out, and relevant differences compared with preoperative temperatures could no longer be observed in any of the groups. CONCLUSION: Current guidelines provide effective protection against perioperative hypothermia. In the current study, this was true for obese as well as normal weight patients.

The RNA Chaperone Hfq Is Essential for Virulence and Modulates the Expression of Four Adhesins in Yersinia enterocolitica.

In Enterobacteriaceae, the RNA chaperone Hfq mediates the interaction of small RNAs with target mRNAs, thereby modulating transcript stability and translation. This post-transcriptional control helps bacteria adapt quickly to changing environmental conditions. Our previous mutational analysis showed that Hfq is involved in metabolism and stress survival in the enteropathogen Yersinia enterocolitica. In this study we demonstrate that Hfq is essential for virulence in mice and influences production of surface pathogenicity factors, in particular lipopolysaccharide and adhesins mediating interaction with host tissue. Hfq inhibited the production of Ail, the Ail-like protein OmpX and the MyfA pilin post-transcriptionally. In contrast Hfq promoted production of two major autotransporter adhesins YadA and InvA. While protein secretion in vitro was not affected, hfq mutants exhibited decreased protein translocation by the type III secretion system into host cells, consistent with decreased production of YadA and InvA. The influence of Hfq on YadA resulted from a complex interplay of transcriptional, post-transcriptional and likely post-translational effects. Hfq regulated invA by modulating the expression of the transcriptional regulators rovA, phoP and ompR. Therefore, Hfq is a global coordinator of surface virulence determinants in Y. enterocolitica suggesting that it constitutes an attractive target for developing new antimicrobial strategies.