Korus Justyna, Wydro Maria, Gołębiowski Maciej, Krakowska Kornelia, Poznański Paweł, Musiał Kinga, Konieczny Andrzej, Augustyniak-Bartosik Hanna, Stojanowski Jakub, Kusztal Mariusz Andrzej, Gołębiowski Tomasz
Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland.
Department of Pediatric Nephrology, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland.
Diagnostics (Basel). 2024 Jun 8;14(12):1219. doi: 10.3390/diagnostics14121219.
: The ability of hemoglobin to bind and dissociate oxygen is crucial in delivering oxygen to tissues and is influenced by a range of physiological states, compensatory mechanisms, and pathological conditions. This may be illustrated by the oxyhemoglobin dissociation curve (ODC). The key parameter for evaluating the oxygen affinity to hemoglobin is p50. The aim of this study was to evaluate the impact of hemodialysis on p50 in a group of patients with chronic kidney disease (CKD). An additional goal was to assess the correlation between p50 and the parameters of erythropoiesis, point-of-care testing (POCT), and other laboratory parameters. : One hundred and eighty patients (106 male, 74 female), mean age 62.5 ± 17 years, with CKD stage G4 and G5 were enrolled in this cross-sectional study. Patients were divided into two groups, including 65 hemodialysis (HD) patients and 115 patients not receiving dialysis (non-HD). During the standard procedure of arteriovenous fistula creation, blood samples from the artery (A) and the vein (V) were taken for POCT. The causes of CKD, as well as demographic and comorbidity data, were obtained from medical records and direct interviews. : The weekly dose of erythropoietin was higher in HD patients than in non-HD patients (4914 ± 2253 UI vs. 403 ± 798 UI, < 0.01), but hemoglobin levels did not differ between these groups. In the group of non-HD patients, more advanced metabolic acidosis (MA) was found, compared to the group with HD. In arterial and venosus blood samples, the non-HD group had significantly lower pH, pCO and HCO. This group had a higher proportion of individuals with MA with HCO < 22 mmol/L (42% vs. 24%, < 0.01). The absolute difference of p50 in arterial and venous blood was determined using the formula Δp50 = (p50-A) - (p50-V). Δp50 was significantly higher in the HD group in comparison to non-HD (0.08 ± 2.05 mmHg vs. -0.66 ± 1.93 mmHg, = 0,02). There was a negative correlation between pH and the p50 value in arterial (pH-A vs. p50-A, r = -0.56, < 0.01) and venous blood (pH-V vs. p50-V, r = -0.45, < 0.01). In non-HD patients, hemoglobin levels correlated negatively with p50 (r = -0.29, < 0.01), whereas no significant relation was found in HD patients. : The ODC in pre-dialysis CKD (non-HD) patients is shifted to the right due to MA, and this is an additional factor influencing erythropoiesis. Hemodialysis restores the natural differences in hemoglobin's dissociation characteristics in the arterial and venous circulation.
血红蛋白结合和释放氧气的能力对于向组织输送氧气至关重要，并受到一系列生理状态、代偿机制和病理状况的影响。这可以通过氧合血红蛋白解离曲线（ODC）来说明。评估氧气与血红蛋白亲和力的关键参数是p50。本研究的目的是评估血液透析对一组慢性肾脏病（CKD）患者p50的影响。另一个目标是评估p50与红细胞生成参数、即时检验（POCT）及其他实验室参数之间的相关性。
180例患者（男性106例，女性74例），平均年龄62.5±17岁，CKD分期为G4和G5期，纳入了本横断面研究。患者分为两组，包括65例血液透析（HD）患者和115例未接受透析的患者（非HD）。在动静脉内瘘建立的标准操作过程中，采集动脉（A）和静脉（V）的血样进行POCT。CKD的病因以及人口统计学和合并症数据来自病历和直接访谈。
HD患者的促红细胞生成素每周剂量高于非HD患者（4914±2253 UI对403±798 UI，<0.01），但两组之间的血红蛋白水平无差异。与HD组相比，非HD患者组发现更严重的代谢性酸中毒（MA）。在动脉和静脉血样中，非HD组的pH、pCO₂和HCO₃⁻显著更低。该组中HCO₃⁻<22 mmol/L的MA个体比例更高（42%对24%，<0.01）。使用公式Δp50 =（p50-A）-（p50-V）确定动脉血和静脉血中p50的绝对差值。与非HD组相比，HD组的Δp50显著更高（0.08±2.05 mmHg对-0.66±1.93 mmHg，P = 0.02）。动脉血（pH-A对p50-A，r = -0.56，<0.01）和静脉血（pH-V对p50-V，r = -0.45，<0.01）中pH与p50值之间存在负相关。在非HD患者中，血红蛋白水平与p50呈负相关（r = -0.29，<0.01），而在HD患者中未发现显著关系。
透析前CKD（非HD）患者的ODC因MA而向右偏移，这是影响红细胞生成的另一个因素。血液透析恢复了动脉和静脉循环中血红蛋白解离特性的自然差异。
