Raijmakers P G, Groeneveld A B, Teule G J, Thijs L G
Department of Nuclear Medicine, Free University Hospital, Amsterdam, The Netherlands.
J Nucl Med. 1996 Aug;37(8):1316-22.
We studied the value of a noninvasive, bedside, dual-radionuclide method (67Ga-circulating transferrin and 99mTc-red blood cells) to measure pulmonary microvascular permeability in efforts to discriminate between pulmonary edema due to adult respiratory distress syndrome (ARDS) and hydrostatic pulmonary edema (HPE).
Patients had respiratory insufficiency and bilateral alveolar pulmonary edema on chest radiographs. All patients, except one, were mechanically ventilated. Patients, were divided into groups according to various sets of etiologic, hemodynamic and ventilatory factors. Group 1 (n = 8) had risk factors for HPE only. Group 2 (n = 5) had risk factors for both ARDS and HPE, such as a pulmonary capillary wedge pressure (PCWP) above 18 torr. Group 3 (n = 13) had risk factors for ARDS only and a PCWP below 18 torr. Patients were also classified on the basis of a lung injury score, using radiographic and ventilatory variables. Group 4 (n = 12) had a score below 2.5 and Group 5 (n = 14) above 2.5, arbitrarily defined as ARDS. Any radioactivity measurements over the lungs and in blood within 72 hr after admission were used to calculate the 1 hr pulmonary leak index as a measure of microvascular permeability (upper limit of normal 14.1 x 10(-3).min-1).
The PLI ( x 10(-3).min-1) was median 10.2 (range 4.4-16.2) in Group 1, 26.8 (14.2-31.9) in Group 2 and 32.3 (23.0-52.4) in Group 3 (p < 0.001). It was 13.3 (4.4-39.9) in Group 4 and 31.1 (14.2-52.4) in Group 5 (p < 0.01). Using the various definitions, the sensitivity of a supranormal pulmonary leak index for ARDS was 100% and the specificity varied between 46% and 75%. In receiver operating characteristic curves, the pulmonary leak index performed best when ARDS and HPE were defined on the basis of risk factors only, and performed better than hemodynamic and equally well as ventilatory variables in discriminating between edema types, if definitions of the latter were mainly based on hemodynamic and ventilatory variables, respectively.
The 67Ga pulmonary leak index is a useful tool to differentiate ARDS from HPE.
我们研究了一种非侵入性的床边双放射性核素方法（67Ga - 循环转铁蛋白和99mTc - 红细胞）测量肺微血管通透性的价值，以努力区分成人呼吸窘迫综合征（ARDS）所致肺水肿与静水压性肺水肿（HPE）。
患者有呼吸功能不全且胸部X线片显示双侧肺泡性肺水肿。除1例患者外，所有患者均接受机械通气。根据各种病因、血流动力学和通气因素将患者分组。第1组（n = 8）仅有HPE的危险因素。第2组（n = 5）有ARDS和HPE的危险因素，如肺毛细血管楔压（PCWP）高于18 torr。第3组（n = 13）仅有ARDS的危险因素且PCWP低于18 torr。还根据肺部损伤评分，利用影像学和通气变量对患者进行分类。第4组（n = 12）评分低于2.5，第5组（n = 14）评分高于2.5，将评分高于2.5者任意定义为ARDS。入院后72小时内对肺部和血液进行的任何放射性测量用于计算1小时肺渗漏指数，作为微血管通透性的指标（正常上限为14.1×10⁻³·min⁻¹）。
第1组肺渗漏指数（×10⁻³·min⁻¹）中位数为10.2（范围4.4 - 16.2），第2组为26.8（14.2 - 31.9），第3组为32.3（23.0 - 52.4）（p < 0.001）。第4组为13.3（4.4 - 39.9），第5组为31.1（14.2 - 52.4）（p < 0.01）。采用各种定义，肺渗漏指数高于正常对ARDS的敏感性为100%，特异性在46%至75%之间。在受试者工作特征曲线中，当仅根据危险因素定义ARDS和HPE时，肺渗漏指数表现最佳；如果后两者的定义分别主要基于血流动力学和通气变量，则在区分水肿类型方面，肺渗漏指数比血流动力学变量表现更好，与通气变量表现相当。
67Ga肺渗漏指数是区分ARDS与HPE的有用工具。
