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731.

Introduction

An anaerobic threshold (AT) of <11ml/min/kg can identify patients at high risk of cardiopulmonary complications after major surgery. The aim of this study was to assess the value of cardiopulmonary exercise testing (CPET) in predicting cardiopulmonary complications in high risk patients undergoing oesophagogastric cancer resection.

Methods

Between March 2008 and October 2010, 108 patients (83 men, 25 women) with a median age of 66 years (range: 38–84 years) underwent CPET before potentially curative resections for oesophagogastric cancers. Measured CPET variables included AT and maximum oxygen uptake at peak exercise (VO2 peak). Outcome measures were length of high dependency unit stay, length of hospital stay, unplanned intensive care unit (ICU) admission, and postoperative morbidity and mortality.

Results

The mean AT and VO2 peak were 10.8ml/min/kg (standard deviation [SD]: 2.8ml/min/kg, range: 4.6–19.3ml/min/kg) and 15.2ml/min/kg (SD: 5.3ml/min/kg, range: 5.4–33.3ml/min/kg) respectively; 57 patients (55%) had an AT of <11ml/min/ kg and 26 (12%) had an AT of <9ml/min/kg. Postoperative complications occurred in 57 patients (29 cardiopulmonary [28%] and 28 non-cardiopulmonary [27%]). Four patients (4%) died in hospital and 21 (20%) required an unplanned ICU admission. Cardiopulmonary complications occurred in 42% of patients with an AT of <9ml/min/kg compared with 29% of patients with an AT of ≥9ml/min/kg but <11ml/min/kg and 20% of patients with an AT of ≥11ml/min/kg (p=0.04). There was a trend that those with an AT of <11ml/min/kg and a low VO2 peak had a higher rate of unplanned ICU admission.

Conclusions

This study has shown a correlation between AT and the development of cardiopulmonary complications although the discriminatory ability was low.  相似文献   
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The objective of this study was to assess the contribution of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) to an early diagnosis of early-onset neonatal sepsis. A cohort of 117 newborn infants delivered during a 1-y period had IL-6, TNF-alpha and IL-1beta, blood and cerebrospinal fluid (CSF) cultures, leucocyte and platelet count collected on the initial evaluation of possible early-onset sepsis. They were divided into four groups: I, positive blood and/or CSF cultures; II, probably infected with clinical sepsis but negative cultures; III, same as group II but mother received antibiotic antepartum; and IV, newborn infants that did not receive any antibiotic therapy. There were no differences among the four groups with respect to mean gestational ages and birthweights, median Apgar scores, type of delivery, or number of newborn infants with leucocyte count <5000 mm(-3) or >25000 mm(-3), platelet count <100000 mm(-3), immature/total neutrophil ratio >0.2, absolute neutrophil count <1000mm(-3) and median IL-1beta levels. Median IL-6 and TNF-alpha levels were significantly higher in groups with patients with a diagnosis of clinical sepsis than in controls. The optimal cut-off point was 32 pg ml(-1) for IL-6 and 12 pg ml(-1) for TNF-alpha. The combination of both provided a sensitivity of 98.5%. In conclusion, the combination of IL-6 and TNF-alpha is a highly sensitive marker of sepsis in the immediate postnatal period.  相似文献   
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Defects in hemostasis in P-selectin-deficient mice   总被引:14,自引:4,他引:14  
Recently, our laboratory showed that platelets, like leukocytes, roll on activated endothelium expressing P-selectin, thus suggesting a role for P-selectin in hemostasis (Frenette et at, Proc Natl Acad Sci USA 92:7450, 1995). We report here that the P-selectin--deficient mice show a 40% prolongation of the bleeding time on amputation of the tip of the tail. Moreover, defective hemostasis was observed in a local Shwartzman- like reaction induced by skin injections of lipopolysaccharide followed by tumor necrosis factor-alpha in the P-selectin--deficient mice. The hemorrhagic lesions, quantitated both macroscopically and microscopically, were twofold larger in the P-selectin--deficient mice. This was also confirmed by measuring the radioactivity in the skin using chromium-labeled red blood cells. Therefore, it is evident that P- selectin plays a role in hemostasis as suggested by its support of platelet rolling.  相似文献   
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