Tavakkoli Fatemeh, Nahavandi Masoud, Wyche Melville Q, Castro Oswaldo
Department of Anesthesiology, College of Medicine, Howard University, Washington, DC 20059, USA.
Clin Ther. 2005 Jul;27(7):1083-8. doi: 10.1016/j.clinthera.2005.07.002.
In patients with sickle cell disease (SCD), cerebral oxygen saturation (rSO(2)) has been reported to be below normal and to increase after red blood cell transfusion.
This study was designed to determine the effects of long-term and short-term hydroxyurea (HU) treatment on cerebral oxygenation in patients with SCD.
This open-label pilot study was conducted at the Department of Anesthesiology and the Center for Sickle Cell Disease, College of Medicine, Howard University, Washington, DC. Adult African American outpatients with SCD and hemoglobin (Hb) genotype HbSS (homozygous sickle Hb) who were receiving long-term (>6 months) HU treatment (15-30 mg/kg . d PO) or who had never received this treatment (control group) were enrolled. Patients in the treated and control groups were matched for age, sex, race, and Hb genotype. Cerebral oximetry (near-infrared spectroscopy) was performed to determine rSO(2) index. In a separate analysis to determine the effects of short-term HU treatment on cerebral oxygenation, hospitalized patients with SCD and vaso-occlusive crisis (VOC)receiving long-term therapy with HU were enrolled. We performed cerebral and pulse (fingernail) oximetry to determine rSO (2)index and arterial oxygen saturation (SpO(2)) after the administration of a single oral dose of HU (500-mg tablet) alone and again after dosing concomitantly with inhaled oxygen.
The study enrolled 11 patients in the HU group (6 women, 5 men; mean [SD] age, 37 [8] years) and 20 controls (8 women, 12 men; mean [SD] age, 35 [6] years). Mean (SD) rSO(2) index was significantly increased (but still low) in patients receiving long-term HU treatment compared with controls (46.1% [6.6%] vs 41.2% [7.6%]; P< 0.025). Hb concentration (9.6 [1.4] g/dL vs 8.5 [1.2] g/dL; P< 0.027), hematocrit (28% [3%] vs 24% [4%]; P < 0.028), and mean corpuscular volume (102% [7%] vs 89% [8%]; P < 0.027) also were significantly higher in the HU group compared with controls. In 8 patients with SCD and VOC (6 men, 2 women; mean [SD] age, 28 [5] years), single-dose HU, either alone or in combination with inhaled oxygen, did not significantly affect cerebral oxygenation, and SpO(2) failed to correlate with rSO(2) index in these patients.
The results of this open-label pilot study in patients with SCD suggest that the low cerebral oxygenation in these patients is significantly improved but not normalized with long-term HU treatment. A single dose of HU, either alone or in combination with inhaled oxygen, did not appear to influence cerebral oxygenation in patients with VOC.
据报道，镰状细胞病（SCD）患者的脑氧饱和度（rSO₂）低于正常水平，且在红细胞输血后会升高。
本研究旨在确定长期和短期羟基脲（HU）治疗对SCD患者脑氧合的影响。
这项开放标签的试点研究在华盛顿特区霍华德大学医学院麻醉科和镰状细胞病中心进行。纳入接受长期（>6个月）HU治疗（15 - 30 mg/kg·d口服）或从未接受过该治疗的成年非裔美国门诊SCD患者以及血红蛋白（Hb）基因型为HbSS（纯合子镰状Hb）的患者（对照组）。治疗组和对照组患者在年龄、性别、种族和Hb基因型方面进行匹配。采用脑血氧饱和度测定法（近红外光谱法）测定rSO₂指数。在另一项确定短期HU治疗对脑氧合影响的分析中，纳入患有SCD和血管闭塞性危机（VOC）且接受HU长期治疗的住院患者。我们在单独口服一剂HU（500毫克片剂）后以及与吸入氧同时给药后，进行脑和脉搏（指尖）血氧饱和度测定，以确定rSO₂指数和动脉血氧饱和度（SpO₂）。
研究纳入HU组11例患者（6例女性，5例男性；平均[标准差]年龄，37[8]岁）和20例对照组患者（8例女性，12例男性；平均[标准差]年龄，35[6]岁）。与对照组相比，接受长期HU治疗的患者平均（标准差）rSO₂指数显著升高（但仍较低）（46.1%[6.6%]对41.2%[7.6%]；P<0.025）。HU组的血红蛋白浓度（9.6[1.4]g/dL对8.5[1.2]g/dL；P<0.027）、血细胞比容（28%[3%]对24%[4%]；P<0.028）和平均红细胞体积（102%[7%]对89%[8%]；P<0.027）也显著高于对照组。在8例患有SCD和VOC的患者（6例男性，2例女性；平均[标准差]年龄，28[5]岁）中，单剂量HU单独或与吸入氧联合使用均未显著影响脑氧合，且这些患者的SpO₂与rSO₂指数无相关性。
这项针对SCD患者的开放标签试点研究结果表明，长期HU治疗可使这些患者较低的脑氧合得到显著改善，但未恢复正常。单剂量HU单独或与吸入氧联合使用似乎对患有VOC的患者脑氧合无影响。
