Bonten M J, Slaughter S, Ambergen A W, Hayden M K, van Voorhis J, Nathan C, Weinstein R A
Department of Internal Medicine, University Hospital Maastricht, The Netherlands.
Arch Intern Med. 1998 May 25;158(10):1127-32. doi: 10.1001/archinte.158.10.1127.
The spread of nosocomial multiresistant microorganisms is affected by compliance with infection control measures and antibiotic use. We hypothesized that "colonization pressure" (ie, the proportion of other patients colonized) also is an important variable. We studied the effect of colonization pressure, compliance with infection control measures, antibiotic use, and other previously identified risk factors on acquisition of colonization with vancomycin-resistant enterococci (VRE).
Rectal colonization was studied daily for 19 weeks in 181 consecutive patients who were admitted to a single medical intensive care unit. A statistical model was created using a Cox proportional hazards regression model including length of stay in the medical intensive care unit until acquisition of VRE, colonization pressure, personnel compliance with infection control measures (hand washing and glove use), APACHE (Acute Physiology and Chronic Health Evaluation) 11 scores, and the proportion of days that a patient received vancomycin or third-generation cephalosporins, sucralfate, and enteral feeding.
With survival until colonization with VRE as the end point, colonization pressure was the most important variable affecting acquisition of VRE (hazard ratio [HR], 1.032; 95% confidence interval [C1], 1.012-1.052; P=.002). In addition, enteral feeding was associated with acquisition of VRE (HR, 1.009; 95% CI, 1.000-1.017; P=.05), and there was a trend toward association of third-generation cephalosporin use with acquisition (HR, 1.007; 95% CI, 0.999-1.015; P=.11). The effects of enteral feeding and third-generation cephalosporin use were more important when colonization pressure was less than 50%. Once colonization pressure was 50% or higher, these other variables hardly affected acquisition of VRE.
Acquisition of VRE was affected by colonization pressure, the use of antibiotics, and the use of enteral feeding. However, once colonization pressure was high, it became the major variable affecting acquisition of VRE.
医院内多重耐药微生物的传播受感染控制措施的依从性和抗生素使用情况的影响。我们推测“定植压力”（即其他患者被定植的比例）也是一个重要变量。我们研究了定植压力、感染控制措施的依从性、抗生素使用情况以及其他先前确定的风险因素对耐万古霉素肠球菌（VRE）定植获得的影响。
对入住单一医学重症监护病房的181例连续患者进行了为期19周的每日直肠定植情况研究。使用Cox比例风险回归模型建立了一个统计模型，该模型包括在医学重症监护病房直至获得VRE的住院时间、定植压力、人员对感染控制措施（洗手和戴手套）的依从性、急性生理与慢性健康状况评估（APACHE）Ⅱ评分，以及患者接受万古霉素或第三代头孢菌素、硫糖铝和肠内营养的天数比例。
以直至发生VRE定植的生存情况作为终点，定植压力是影响VRE获得的最重要变量（风险比[HR]，1.032；95%置信区间[CI]，1.012 - 1.052；P = 0.002）。此外，肠内营养与VRE的获得相关（HR，1.009；95%CI，1.000 - 1.017；P = 0.05），并且使用第三代头孢菌素与获得VRE存在关联趋势（HR，1.007；95%CI，0.999 - 1.015；P = 0.11）。当定植压力小于50%时，肠内营养和使用第三代头孢菌素的影响更为重要。一旦定植压力达到50%或更高，这些其他变量几乎不影响VRE的获得。
VRE的获得受定植压力、抗生素使用和肠内营养的影响。然而，一旦定植压力较高，它就成为影响VRE获得的主要变量。
