Pittet D, Wenzel R P
Division of General Medicine, University of Iowa College of Medicine, Iowa City, USA.
Arch Intern Med. 1995 Jun 12;155(11):1177-84. doi: 10.1001/archinte.155.11.1177.
Nosocomial bloodstream infections occur at a rate of 1.3 to 14.5 per 1000 hospital admissions and are believed to lead directly to 62,500 deaths per year in the United States. Measures of the incidence and the proportion of all hospital deaths related to deaths from these infections provide estimates of their impact. The objectives of the study were to characterize the secular trends in nosocomial bloodstream infection at a single institution and to estimate the population-attributable risk for death among patients experiencing the infection.
A 12-year retrospective study using prospectively collected data from a hospital-wide surveillance system for nosocomial infections in a 900-bed tertiary care institution. All patients (N = 260,834) admitted to the institution between 1980 and 1992 were included in the study. Bloodstream infection rates were calculated for the 10 leading groups of pathogens, and trends were analyzed using simple linear regression. In-hospital mortality rates from patients who did or did not develop nosocomial blood stream infections were compared.
Between 1980 and 1992, a total of 3077 patients developed 3464 episodes of nosocomial bloodstream infection. The crude infection rates increased linearly from 6.7 to 18.4 per 1000 discharges (0.83 to 1.72 episodes per 1000 patient-days) during the 12-year study period (r = .87). Increases in the infection rates were due to gram-positive cocci (r = .96) and yeasts (r = .95) and essentially explained by infections caused by coagulase-negative staphylococci, Staphylococcus aureus, enterococci, and Candida species, respectively. Although the crude mortality in patients with nosocomial bloodstream infections decreased from 51% in 1981 to 29% in 1992, the in-hospital population-attributable mortality among infected patients increased from 3.55 deaths per 1000 discharges in 1981 to 6.22 per 1000 discharges in 1992 (r = .67). The etiologic fraction or the proportion of deaths in patients with bloodstream infection to all deaths occurring in the hospital increased from 11.4% in 1981 to 20.4% in 1992 (r = .59).
The incidence, the etiologic fraction, and the population-attributable risk for death among patients experiencing nosocomial bloodstream infections increased progressively during the last decade.
医院血流感染的发生率为每1000例住院患者中有1.3至14.5例，据信在美国每年直接导致62,500人死亡。对所有与这些感染导致的死亡相关的医院死亡发生率和比例的测量提供了对其影响的估计。本研究的目的是描述单一机构中医院血流感染的长期趋势，并估计感染患者中死亡的人群归因风险。
一项为期12年的回顾性研究，使用前瞻性收集的来自一家拥有900张床位的三级医疗机构全院医院感染监测系统的数据。1980年至1992年间入住该机构的所有患者（N = 260,834）均纳入研究。计算了10种主要病原体组的血流感染率，并使用简单线性回归分析趋势。比较了发生或未发生医院血流感染的患者的住院死亡率。
1980年至1992年间，共有3077例患者发生了3464次医院血流感染发作。在12年的研究期间，粗感染率从每1000例出院患者中的6.7例线性增加至18.4例（每1000患者日0.83至1.72次发作）（r = 0.87）。感染率的增加归因于革兰氏阳性球菌（r = 0.96）和酵母菌（r = 0.95），分别主要由凝固酶阴性葡萄球菌、金黄色葡萄球菌、肠球菌和念珠菌属引起的感染所解释。尽管医院血流感染患者的粗死亡率从1981年的51%降至1992年的29%，但感染患者中的住院人群归因死亡率从1981年每1000例出院患者中的3.55例死亡增加至1992年的每1000例出院患者中的6.22例（r = 0.67）。血流感染患者死亡的病因分数或在医院发生的所有死亡中所占比例从1981年的11.4%增加至1992年的20.4%（r = 0.59）。
在过去十年中，医院血流感染患者的发病率、病因分数和死亡的人群归因风险逐渐增加。
