[Reduced preoperative fasting periods. Current status after a survey of patients and colleagues]. / Verkürzte präoperative Nüchternheit. Erhebung eines Istzustands nach Analyse von Patienten- und Mitarbeiteraussagen.

BACKGROUND: Since October 2004 German Anaesthesiology Societies have officially recommended a decreased fasting period of 2 h for clear fluids and 6 h for solid food before elective surgery. A survey of patients and health care workers was carried out in our university clinic to assess the implementation of the new fasting recommendations. METHODS: Surgical patients (n=865) as well as physicians and nurses specialized in anaesthesia and surgery (n=2,355) were invited to complete a written questionnaire. The survey inquired about prescribed and practiced duration of fasting, attitudes towards reduced preoperative fasting and knowledge of the new guidelines. RESULTS: Data from 784 patients (91%) and 557 health care workers (24%) were analysed. Patients reported mean fasting times of 10+/-5 h for fluids and 15+/-4 h for solid food. Of the patients 52% and 16% would have preferred to drink and eat before surgery, respectively and 10% were informed about the new recommendations of shorter preoperative fluid and solid fasting. Such patients reported significantly reduced fasting times for fluids compared with those who were recommended to fast for the traditional longer periods (8+/-6 versus 12+/-4 h, p<0.001). Preoperative fasting advice remembered by the patients significantly differed from the prescribed recommendations (2 h fluid fasting, 22 versus 53%, p<0.001). Anaesthesiologists were significantly more knowledgeable of the new guidelines (90 versus 32-42%, p<0.001) and significantly more willing to recommend the new short preoperative fasting times (75 versus 15-19%, p<0.001) than other health care workers. Of all health care workers 82% and 32% reported patients' frequent desire to drink and eat before surgery, respectively, 92% considered reduced preoperative fasting to be positive, 76% feared increased risks for patients and 42% expected a decreased flexibility in their daily work. CONCLUSION: The current guidelines for preoperative fasting have not been widely implemented. Besides a knowledge discrepancy, remarkable concerns remain regarding higher risk for patients which may be important barriers to implementation. Nevertheless, health care workers are aware of patients' desire for shorter preoperative fasting. If the new guidelines are recommended patients will make use of them. Further training of staff and adequate implementation tools are needed.

Effects of N-acetylcysteine and tirilazad mesylate on intestinal functional capillary density, leukocyte adherence, mesenteric plasma extravasation and cytokine levels in experimental endotoxemia in rats.

INTRODUCTION: The study's objective was to determine the effects of the administration of N-acetylcysteine (NAC) and of tirilazad mesylate (TM) on intestinal functional capillary density, mesenteric plasma extravasation, leukocyte adherence and on cytokine release during experimental endotoxemia in rats. METHODS: In a prospective, randomized, controlled animal study, 80 male Wistar rats were examined in 2 test series. Both series were divided into 4 groups. Group 1 served as control group (CON group). Group 2 (LPS group), group 3 (NAC group) and group 4 (TM group) received endotoxin infusions (10 mg/kg over 2 h). In NAC group 150 mg/kg body weight NAC was administered after the first 30 minutes of endotoxemia intravenously. In TM group, 10 mg/kg body weight TM was administered after the first 30 minutes of endotoxemia intravenously. Animals of the series 1 underwent studies of leukocyte adherence on submucosal venular endothelium of the small bowel wall and intestinal functional capillary density (FCD) in the intestinal mucosa and the circular as well as the longitudinal muscle layer by intravital fluorescence microscopy (IVM). Plasma levels of interleukin 1beta (IL-1beta), interferone gamma (IFN-gamma) and soluble intercellular adhesion molecule1 (s-ICAM 1) as well as white blood cell count (WBC) were estimated. In the animals of the series 2 mesenteric plasma extravasation was determined by IVM and plasma levels of tumor necrosis factor alpha (TNF-alpha), IL-4, IL-6, IL-10 and malondialdehyde (MDA) were estimated. RESULTS: After LPS administration, FCD in the villi intestinales was unchanged and in the longitudinal muscularis layer it was increased. There was no effect of NAC or TM administration on FCD.Although the plasma extravasation was not significantly influenced by LPS administration, TM administration resulted in a lower plasma extravasation in the TM group compared to the other groups. After endotoxin challenge, the firmly adherence of leukocytes to vascular endothelium as a parameter of leukocyte activation in endotoxemia was increased but NAC or TM administration had no influence on leukocyte adherence. The plasma levels of IL-1beta, IL-6, IL-10, TNF-alpha, IFN-gamma and sICAM-1 were increased in the endotoxemic groups (LPS group, NAC group and TM group) and the WBC was decreased compared to controls. IL-4 levels were unchanged during observation period. Plasma MDA levels were not influenced by LPS administration compared to controls. The administration of NAC resulted in lower sICAM-1 and MDA levels compared to the LPS group. The IL-1beta, IL-6, IL-10, TNF-alpha and IFN-gamma plasma levels were not influenced by NAC or TM administration. CONCLUSIONS: In this posttreatment sepsis model in rats, NAC administration resulted in lower sICAM-1 and MDA levels compared to the LPS treated animals. TM administration reduced the plasma extravasation in this model.

Laparoscopic spray application of fibrin sealant effects on hemodynamics and spray efficiency at various application pressures and distances.

BACKGROUND: Laparoscopic resections of parenchymal organs are increasingly performed. However, little is known about the effects of laparoscopic fibrin sealant spray applications on intraabdominal pressure (IAP) and hemodynamics. METHODS: Cardiac and pulmonary monitoring was performed via two central venous pressure lines in the thoracic and abdominal vena cava, a pulmonary artery catheter, and a peripheral artery line. Air was sprayed into the abdomen at pressures of 2, 3, and 4 bar for 30 s. According to the group, a valve on a trocar was open or closed. To optimize fibrin sealant application, the sealant was sprayed at three different application pressures (2, 2.5, and 3 bar) and distances (2, 3.5, and 5 cm). RESULTS: All spray simulations caused a significant increase in the IAP. During the first 10 s of spraying, the IAP increase was 5 mmHg or less, but rose rapidly during the last 20 s of spraying. The IAP increase resulted in decreased pulmonary compliance. Pulmonary resistance and the central venous pressures of both the thoracic and abdominal vena cava increased. At application pressures of 3 and 4 bar, the IAP increase was greater than 2 bar of pressure, reaching IAP values exceeding 35 mmHg. Spray mist formation was primarily dependent on application pressure, whereas clot formation and surface coverage depended on both application pressure and distance. The best results were achieved with an application pressure of 2.5 bar and a distance of 5 cm from the surface. CONCLUSIONS: This study shows that fibrin sealants can be used safely in laparoscopic procedures. Keeping the spray periods short and allowing air to escape from the abdomen can minimize the IAP increase. According to our results, a laparoscopic spray application of fibrin sealant should start with an insufflation pressure of 10 mmHg, an application pressure of 2.5 bar, and an application distance of 5 cm with a valve on the trocar left open.