Spack L, Havens P L, Griffith O W
Department of Pediatrics, Children's Hospital of Wisconsin, Milwaukee 53201, USA.
Crit Care Med. 1997 Jun;25(6):1071-8. doi: 10.1097/00003246-199706000-00027.
The systemic inflammatory response syndrome (SIRS) is typified by the presence of fever, hemodynamic changes, and end organ dysfunction. Endothelial cell activation leads to overproduction of nitric oxide, which results in sustained vasodilation and hypotension. This study was undertaken to determine the sensitivity, specificity, and positive and negative predictive values of plasma nitrite/nitrate measurements in identifying patients with clinical characteristics of SIRS, as defined by criteria based on physician diagnosis.
Prospective cohort study with consecutive sampling of patients.
Tertiary, multidisciplinary, pediatric intensive care unit (ICU) at Children's Hospital of Wisconsin.
Patients were divided into five groups. There were 16 pediatric controls undergoing elective surgery and 177 pediatric ICU patients without and 46 pediatric ICU patients with physician-diagnosed sepsis, septic shock, SIRS, or sepsis syndrome documented in the medical record (all considered physician-diagnosed sepsis). The 223 pediatric ICU patients included 195 pediatric ICU patients not meeting and 28 pediatric ICU patients meeting predetermined physiologic criteria for SIRS (considered criteria-based sepsis).
Blood samples were obtained for quantitative nitrite/nitrate analysis at the time of admission to the pediatric ICU and daily until discharge.
Mean plasma nitrite/nitrate concentrations in the controls were 34.5 +/- 12 microM (95th percentile 54 microM). In pediatric ICU patients without and with physician-diagnosed sepsis, mean plasma nitrite/nitrate concentrations were 39 +/- 24 microM (p > .05 compared with controls) and 127 +/- 91 microM (p < .0001 compared with both controls and patients without physician-diagnosed sepsis), respectively. In pediatric ICU patients without and with criteria-based sepsis, the mean total plasma nitrite/nitrate concentrations were 56 +/- 59 microM (p = .008 compared with controls) and 80 +/- 64 microM (p = .003 compared with patients without criteria-based sepsis), respectively. The ability of plasma nitrite/nitrate > 54 microM to identify patients with physician-diagnosed sepsis is characterized as follows: 87% sensitivity, 77% specificity, 50% positive predictive value, and 96% negative predictive value. The ability of plasma nitrite/nitrate > 54 microM to identify patients with criteria-based sepsis is characterized as follows: 61% sensitivity, 68% specificity, 21% positive predictive value, and 92% negative predictive value.
Clinical diagnosis of SIRS is strongly associated with increased total plasma nitrite/nitrate concentrations in pediatric patients in the pediatric ICU. Many patients with increased nitrite/nitrate concentrations have inflammation without having a clinical diagnosis of SIRS. Our data suggest that increased plasma nitrite/nitrate concentrations are the standard for identifying patients with inflammation in the pediatric ICU.
全身炎症反应综合征（SIRS）的典型表现为发热、血流动力学改变及终末器官功能障碍。内皮细胞活化导致一氧化氮过度生成，进而引起持续性血管舒张和低血压。本研究旨在确定血浆亚硝酸盐/硝酸盐测量在识别具有SIRS临床特征患者中的敏感性、特异性、阳性预测值和阴性预测值，SIRS的临床特征依据基于医生诊断的标准来定义。
对患者进行连续抽样的前瞻性队列研究。
威斯康星儿童医院的三级多学科儿科重症监护病房（ICU）。
患者分为五组。有16名接受择期手术的儿科对照患者，177名儿科ICU患者未被医生诊断为败血症，46名儿科ICU患者在病历中有医生诊断的败血症、感染性休克、SIRS或败血症综合征记录（均视为医生诊断的败血症）。这223名儿科ICU患者包括195名未符合及28名符合SIRS预定生理标准的儿科ICU患者（视为基于标准的败血症）。
在儿科ICU入院时采集血样进行亚硝酸盐/硝酸盐定量分析，每天采集直至出院。
对照组血浆亚硝酸盐/硝酸盐平均浓度为34.5±12微摩尔/升（第95百分位数为54微摩尔/升）。在未被医生诊断为败血症和被医生诊断为败血症的儿科ICU患者中，血浆亚硝酸盐/硝酸盐平均浓度分别为39±24微摩尔/升（与对照组相比，p>.05）和127±91微摩尔/升（与对照组和未被医生诊断为败血症的患者相比，p<.0001）。在未符合基于标准的败血症和符合基于标准的败血症的儿科ICU患者中，血浆亚硝酸盐/硝酸盐总平均浓度分别为56±59微摩尔/升（与对照组相比，p=.008）和80±64微摩尔/升（与未符合基于标准的败血症的患者相比，p=.003）。血浆亚硝酸盐/硝酸盐>54微摩尔/升识别医生诊断的败血症患者的能力特征如下：敏感性87%，特异性77%，阳性预测值50%，阴性预测值96%。血浆亚硝酸盐/硝酸盐>54微摩尔/升识别基于标准的败血症患者的能力特征如下：敏感性61%，特异性68%，阳性预测值21%，阴性预测值92%。
儿科ICU中儿科患者SIRS的临床诊断与血浆亚硝酸盐/硝酸盐总浓度升高密切相关。许多亚硝酸盐/硝酸盐浓度升高的患者有炎症，但未被临床诊断为SIRS。我们的数据表明，血浆亚硝酸盐/硝酸盐浓度升高是识别儿科ICU中炎症患者的标准。
