Okur Nilüfer, Tayman Cüneyt, Büyüktiryaki Mehmet, Kadıoğlu Şimşek Gülsüm, Ozer Bekmez Buse, Altuğ Nahide
Zekai Tahir Burak Women's Health Education and Research Hospital, Ankara, Turkey.
J Clin Lab Anal. 2019 Feb;33(2):e22664. doi: 10.1002/jcla.22664. Epub 2018 Sep 2.
Serum lactate levels provide information on metabolic capacity at the cellular level. In addition, lactate reflects tissue perfusion and oxygenation status. The aim of this study was to determine the usefulness of high lactate levels as a marker in hemodynamically significant patent ductus arteriosus (hsPDA), which may lead to tissue perfusion defects.
Preterm infants with gestational age ≤32 weeks and birthweight ≤1500 g were included. Lactate levels were determined at postnatal 48-72 hours before echocardiographic evaluation. Eligible infants were divided into two groups as infants with and without hsPDA. Cut-off values for lactate were taken as lactate >4 mmol/L, identified as a high lactate level. Infants were also divided into two groups according to lactate levels as group I: lactate levels >4 mmol/L and group II: lactate levels ≤4 mmol/L. Haemodynamic PDA and lactate levels were compared.
A total of 119 patients with gestational age ≤32 weeks and birthweight ≤1500 g were included in the study. Fifty patients had echocardiographic hsPDA and 69 patients had no PDA. Twelve (24%) of the patients with hsPDA and 22 (31.9%) of the non-hsPDA patients had a lactate level of 4 mmol/L (P = 0.392). There was no correlation between hsPDA presence and lactate levels (P = 0.35).
High lactate levels are multifactorial and usually indicate impairment of tissue perfusion. There are a number of factors that can lead to impaired tissue perfusion in preterm infants. For the first time in this study, it was shown that lactate levels did not significantly increase in the presence of hemodynamically significant PDA. This may be due to the fact that peripheral tissue perfusion in the presence of hemodynamic PDA does not deteriorate enough to cause an increase in anaerobic metabolism.
血清乳酸水平可提供细胞水平代谢能力的信息。此外，乳酸反映组织灌注和氧合状态。本研究的目的是确定高乳酸水平作为血流动力学显著的动脉导管未闭（hsPDA）标志物的有用性，hsPDA可能导致组织灌注缺陷。
纳入孕周≤32周且出生体重≤1500g的早产儿。在超声心动图评估前的出生后48 - 72小时测定乳酸水平。符合条件的婴儿分为有hsPDA和无hsPDA两组。乳酸的截断值设定为乳酸>4mmol/L，即高乳酸水平。婴儿也根据乳酸水平分为两组：I组：乳酸水平>4mmol/L；II组：乳酸水平≤4mmol/L。比较血流动力学PDA和乳酸水平。
本研究共纳入119例孕周≤32周且出生体重≤1500g的患者。50例患者经超声心动图诊断为hsPDA，69例患者无PDA。hsPDA患者中有12例（24%）乳酸水平为4mmol/L，非hsPDA患者中有22例（31.9%）乳酸水平为4mmol/L（P = 0.392）。hsPDA的存在与乳酸水平之间无相关性（P = 0.35）。
高乳酸水平是多因素的，通常表明组织灌注受损。有许多因素可导致早产儿组织灌注受损。本研究首次表明，在存在血流动力学显著的PDA时，乳酸水平并未显著升高。这可能是由于在存在血流动力学PDA时，外周组织灌注恶化程度不足以导致无氧代谢增加。
