Tetteroo G W, Wagenvoort J H, Mulder P G, Ince C, Bruining H A
Department of Surgery, University Hospital Rotterdam, The Netherlands.
Crit Care Med. 1993 Nov;21(11):1692-8. doi: 10.1097/00003246-199311000-00018.
Current studies concerning selective decontamination of the digestive tract have failed to demonstrate a decrease in the length of hospital stay and mortality rate, despite the finding of a significantly lower number of infections. To evaluate this issue in more detail, the relationship between the mortality rate and length of stay with respect to colonization and infections was studied within a group of patients receiving selective decontamination. Special attention was given to the efficacy of decontamination within each patient. The main question addressed was whether an effect on mortality rate was present, and if so, why this effect was not apparent until now.
Prospective observational cohort study.
Surgical intensive care unit (ICU) in a university hospital.
Ninety-seven patients primarily admitted into the surgical ICU who received selective decontamination. Transferred patients were excluded. The majority of the surgeries were elective, and all patients completed the follow-up.
All patients received polymyxin E, amphotericin B, and norfloxacin four times a day in a 2% solution of Orabase orally and enterally as suspensions of 200, 500, and 50 mg, respectively. Assessment of the efficacy of selective decontamination was done by identification of Gram-negative microorganisms in surveillance cultures from the oropharynx and rectum. Predicted mortality rates for each patient were calculated with a logistic regression formula.
A possible benefit of selective decontamination of the digestive tract would be expressed by lower actual mortality rates compared to predicted mortality rates. Since we expected the efficacy of decontamination to have an influence on infection and mortality rates, we evaluated these rates in terms of successful or unsuccessful decontamination. Most patients (n = 72) were successfully decontaminated. Actual death rates in these patients were significantly lower than the expected rates (as calculated by the Acute Physiology and Chronic Health Evaluation [APACHE] II scoring system) (18% vs. 40%, p = .006), whereas no difference was found in those patients with failed decontamination (n = 25, death rate 44%). The patients with unsuccessful selective decontamination had significantly longer hospital (52 vs. 34 days) and ICU lengths of stays (23 vs. 9 days; p = .002) and higher mortality rates (44% vs. 18%, p = .020) when compared with those patients who were successfully decontaminated.
These results indicate that selective decontamination is beneficial in terms of mortality rate and length of stay in surgical patients only when successful decontamination has been achieved. The subgroup of patients for whom decontamination is not successful might be responsible for the obscurity in mortality effects of selective decontamination in studies until now. It is expected that identification and subsequent elimination of possible risk factors that cause a failure of selective decontamination can result in lower morbidity and mortality rates in critically ill, surgical patients admitted to the ICU.
目前关于消化道选择性去污的研究未能证明住院时间和死亡率有所降低，尽管发现感染数量显著减少。为了更详细地评估这个问题，我们在一组接受选择性去污的患者中研究了定植和感染与死亡率及住院时间之间的关系。特别关注了每位患者的去污效果。主要探讨的问题是是否存在对死亡率的影响，如果存在，为何到目前为止这种影响不明显。
前瞻性观察队列研究。
大学医院的外科重症监护病房（ICU）。
97名主要入住外科ICU并接受选择性去污的患者。排除了转院患者。大多数手术为择期手术，所有患者均完成了随访。
所有患者每天4次口服多粘菌素E、两性霉素B和诺氟沙星，分别以2%的Orabase溶液和200、500及50mg的悬浮液经口和肠道给药。通过从口咽和直肠的监测培养物中鉴定革兰氏阴性微生物来评估选择性去污的效果。使用逻辑回归公式计算每位患者的预测死亡率。
消化道选择性去污的一个可能益处是实际死亡率低于预测死亡率。由于我们预期去污效果会对感染率和死亡率产生影响，所以我们根据去污成功与否来评估这些比率。大多数患者（n = 72）去污成功。这些患者的实际死亡率显著低于预期死亡率（通过急性生理与慢性健康评估[APACHE]II评分系统计算）（18%对40%，p = 0.006），而在去污失败的患者（n = 25，死亡率44%）中未发现差异。与去污成功的患者相比，选择性去污失败的患者住院时间（52天对34天）和ICU住院时间（23天对9天；p = 0.002）显著更长，死亡率更高（44%对18%，p = 0.020）。
这些结果表明，仅当成功实现去污时，消化道选择性去污对手术患者的死亡率和住院时间才有益。到目前为止，去污不成功的患者亚组可能是导致选择性去污对死亡率影响不明确的原因。预计识别并随后消除导致选择性去污失败的可能风险因素可降低入住ICU的重症手术患者的发病率和死亡率。
