McKeon J L, Saunders N A, Murree-Allen K, Olson L G, Gyulay S, Dickeson J, Houghton A, Wlodarczyk J, Hensley M J
Department of Thoracic Medicine, Royal Newcastle Hospital, New South Wales, Australia.
Am Rev Respir Dis. 1990 Jul;142(1):8-13. doi: 10.1164/ajrccm/142.1.8.
A noninvasive, inexpensive method of excluding significant sleep-associated hypoxemia would be desirable for patients being investigated and treated for obstructive sleep apnea (OSA). Sixty-eight such patients provided specimens before and after sleep studies for estimation of urinary uric acid:creatinine ratio (UA:Cr), serum erythropoietin (EPO), and blood 2,3-diphosphoglycerate (2,3-DPG). Mean (SD) morning 2,3-DPG was higher in 26 patients with overnight hypoxemia than in 42 normoxemic patients (2.54 [0.46] versus 2.24 [0.44] mmol/L; p = 0.01). Neither overnight change nor absolute values of serum EPO or urinary UA:Cr were significantly different between hypoxemic and normoxemic groups. There was a diurnal variation in serum EPO in normoxemic patients (P.M. EPO = 14.8 [7.1] mU/ml; A.M. EPO = 10.7 [7.1] mU/ml; p less than 0.05) but not in hypoxemic patients. Eighteen hypoxemic patients were restudied after using nasal continuous positive airway pressure (nCPAP) for at least 4 wk. Seven normoxemic patients not using nCPAP were restudied after a similar time. There were no significant differences between pretreatment and posttreatment nights in absolute values or percentage overnight change of blood 2,3-DPG or serum EPO in either group. In the hypoxemic (nCPAP) group, overnight change in urinary UA:Cr was lower on the second night (p = 0.04); there was no significant change in the control group. We conclude that although urinary UA:Cr, serum EPO, and 2,3-DPG may be physiologically related to hypoxemia, none of these measures can be used to predict accurately the presence of moderate nocturnal hypoxemia in patients with OSA or in monitoring the effect of their therapy.
对于正在接受阻塞性睡眠呼吸暂停（OSA）检查和治疗的患者而言，一种非侵入性、低成本的排除显著睡眠相关低氧血症的方法将是很有必要的。68例此类患者在睡眠研究前后提供了标本，用于评估尿尿酸：肌酐比值（UA:Cr）、血清促红细胞生成素（EPO）和血液2,3 - 二磷酸甘油酸（2,3 - DPG）。26例夜间低氧血症患者的平均（标准差）晨起2,3 - DPG高于42例血氧正常患者（2.54 [0.46] 对比2.24 [0.44] mmol/L；p = 0.01）。低氧血症组和血氧正常组之间，血清EPO的夜间变化及绝对值或尿UA:Cr均无显著差异。血氧正常患者的血清EPO存在昼夜变化（下午EPO = 14.8 [7.1] mU/ml；上午EPO = 10.7 [7.1] mU/ml；p < 0.05），而低氧血症患者则无。18例低氧血症患者在使用鼻持续气道正压通气（nCPAP）至少4周后再次进行研究。7例未使用nCPAP的血氧正常患者在相似时间后再次进行研究。两组中，治疗前和治疗后夜间血液2,3 - DPG或血清EPO的绝对值或夜间变化百分比均无显著差异。在低氧血症（nCPAP）组中，第二晚尿UA:Cr的夜间变化较低（p = 0.04）；对照组无显著变化。我们得出结论，尽管尿UA:Cr、血清EPO和2,3 - DPG可能在生理上与低氧血症相关，但这些指标均不能准确预测OSA患者中度夜间低氧血症的存在或监测其治疗效果。
