在以往的研究中，ICU住院天数被证实是增加ICU患者病死率独立危险因素［4，12］，但在本研究中，ICU住院天数与ICU患者病死率无明显关联(P＞0.05)，存活患者与死亡患者ICU住院天数中位数较接近。

    与以往的研究一样，本研究显示机械通气显著增加ICU患者病死率［3，12］。肺炎是ICU最常见的医院感染。机械通气患者由于气管插管破坏了口咽部与气管间的屏障，损害了对口腔分泌物的有效清除功能，容易发生沿气管导管外呼吸道分泌物的吸入，使呼吸机相关性肺炎的发生明显增加。本研究中发生呼吸道感染和脓毒症的患者，死亡风险显著增加，医院获得性肺炎是增加ICU患者病死率独立危险因素。

    使用激素、化疗药物等免疫抑制剂可降低机体免疫功能，增加ICU患者医院感染发生的风险［5］。本研究中使用激素、化疗药物等免疫抑制剂的患者往往伴有严重的基础疾病，入ICU后更易发生医院感染，因此病死率较高。

    中心静脉导管置入可增加血源性感染机会。在本研究中中心静脉导管相关性菌血症的发生仅为7%，可能与使用广谱抗生素后中心静脉导管培养阳性率较低有关。

    总之，ICU危重患者是医院的高危人群，影响ICU危重患者病死率的危险因素较多，信捷职称论文写作发表网，包括高龄、APACHE II评分、使用机械通气、医院感染、鼻饲、免疫抑制剂、气管切开等因素，在预防和干预治疗时应针对其危险因素加强防护，采取相应的措施，加强监测，提高患者的生存率。

    【参考文献】

    1 Brown RB, Hosmer D, Chen HC. A comparision of infection in different ICUs within the same hospital. Crit Care Med,1985,13:472-476.

    2 Daschner F. Nosocomial infections in intensive care units. Crit Care Med,1985,11:284-287.

    3 Appelgren P, Hellstrom I,Weitzberg E, et al. Risk factors for nosocomial intensive care infection: a long-term prospective analysis. Acta Anaesthesiol Scand,2001,45:710-719.

    4 Craven DE, Kunches LM, Lichtenberg DA, et al. Nosocomial infection and fatality in medical and surgical intensive care unit patients. Arch Intern Med,1988,148:1161-1168.

    5 Vincent JL. Nosocomial infections in adult intensive-care units. Lancet,2003,361:2068-2077.

    6 Rordorf G, KoroshetzW, Efird JT, et al. Predictors of mortality in stroke patients admitted to an intensive care unit. Crit Care Med,2000,28:1301-1305.

    7 Ibrahim EH, Sherman G, Ward S, et al. The influence of inadequate antimicrobial treatment of bloodstream infections on patient outcomes in the ICU setting. Chest,2000,118:146-155.

    8 Rocker G, Cook D, Sjokvist P, et al.Clinician predictions of intensive care unit mortality. Crit Care Med,2004,32:1149-1154.

    9 Stephan F, Cheffi A, Bonnet F. Nosocomial infections and outcome of critically ill elderly patients after surgery. Anesthesiology,2001,94: 407-414.

    10 Rockwood K, Noseworthy TW, Gibney RT, et al. One-year outcome of elderly and young patients admitted to intensive care units. Crit Care Med,1993,21:687-691.

    11 Niskanen M, Kari A, Nikki P,et al. Acute physiology and chronic health evaluation (APACHE II) and Glasgow coma scores as predictors of outcome from intensive care after cardiac arrest. Crit Care Med,1991,19:1465-1473.

    12 Bercault N, Boulain T. Mortality rate attributable to ventilator associated nosocomial pneumonia in an adult intensive care unit :a prospective case-control study. Crit Care Med,2001,29:2303-2309.