Department of Anesthesiology and Critical Care, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.
Anesthesiology. 2011 Sep;115(3):568-74. doi: 10.1097/ALN.0b013e31822a702f.
After brain death, adrenal insufficiency (AI) is very common and may be one of the mechanisms that contributes to hemodynamic instability and loss of potential organ donors. However, when diagnosed by total cortisol measurement, critically ill patients may be overdiagnosed as having AI. The aims of this study were to assess the prevalence of AI when diagnosed using free cortisol measurement and the accuracy of total cortisol measurement to diagnose AI in brain-dead patients.
All consecutive brain-dead patients were included in this single-center noninterventional clinical observation study. Assessment of adrenocorticotropin, corticosteroid-binding globulin, baseline and tetracosactin-stimulated serum free and total cortisol concentrations were performed. AI was defined as a baseline free cortisol concentration ≤ 55 nM(-1) and/or Δ free cortisol ≤ 55 nM(-1). Patients were considered to have a low albumin concentration if less than 25 g · L(-1) and a low corticosteroid-binding globulin concentration if less than 27 mg · L(-1) in men or 31 mg · L(-1) in women.
Among the 42 included patients, the incidence of AI was 83% (95% CI, 69-93%). Baseline total cortisol was correlated with baseline free cortisol, whatever the albumin or corticosteroid-binding globulin concentration. The area under the receiver operating characteristic curve of baseline total cortisol measurement to diagnose AI was 0.94 (95% CI, 0.81-0.98). The optimal cutoff was 485 nM(-1), providing a sensitivity and a specificity of 89% and 100%, respectively.
Total baseline cortisol measurement is accurate and sufficient to diagnose AI in brain-dead patients, even if albumin or corticosteroid-binding globulin concentrations are low.
脑死亡后，肾上腺功能不全（AI）非常常见，可能是导致血流动力学不稳定和潜在器官捐献者丧失的机制之一。然而，通过总皮质醇测量诊断时，危重病患者可能会被过度诊断为 AI。本研究的目的是评估使用游离皮质醇测量诊断 AI 的患病率，以及总皮质醇测量诊断脑死亡患者 AI 的准确性。
所有连续的脑死亡患者均纳入本单中心非干预性临床观察研究。评估促肾上腺皮质激素、皮质类固醇结合球蛋白、基础和四氢皮质素刺激的血清游离和总皮质醇浓度。AI 定义为基础游离皮质醇浓度≤55 nM(-1)和/或Δ游离皮质醇≤55 nM(-1)。如果男性皮质类固醇结合球蛋白浓度<27 mg·L(-1)或女性<31 mg·L(-1)，则认为患者白蛋白浓度<25 g·L(-1)。
在 42 例纳入的患者中，AI 的发生率为 83%（95%CI，69-93%）。无论白蛋白或皮质类固醇结合球蛋白浓度如何，基础总皮质醇与基础游离皮质醇相关。基础总皮质醇测量诊断 AI 的受试者工作特征曲线下面积为 0.94（95%CI，0.81-0.98）。最佳截断值为 485 nM(-1)，灵敏度和特异性分别为 89%和 100%。
即使白蛋白或皮质类固醇结合球蛋白浓度较低，总基础皮质醇测量也能准确且充分地诊断脑死亡患者的 AI。
