Rungatscher Alessio, Milani Elisabetta, Covajes Cecilia, Hallström Seth, Gottin Leonardo, Guidi Gian Cesare, Luciani Giovanni Battista, Faggian Giuseppe
Department of Surgery, Division of Cardiac Surgery, University of Verona, Verona, Italy.
Department of Surgery, Division of Cardiac Surgery, University of Verona, Verona, Italy.
Microvasc Res. 2017 Jul;112:109-114. doi: 10.1016/j.mvr.2017.04.001. Epub 2017 Apr 4.
The hemolytic product free-hemoglobin (fHb) reduces nitric oxide (NO) bioavailability. The present study aims to establish whether administration of different blood transfusions result in increased circulating fHb levels and NO consumption with effects on arterial NO-dependent blood flow in patients undergoing CABG surgery.
Ninety-five consecutive patients undergoing elective CABG surgery were prospectively divided in four groups based on blood transfusion requirements during surgery: stored blood cells (SBC, n. 21), intraoperative autologous salvaged blood (ASB, n. 25), SBC and ASB (n.22), no transfusion (control, n. 27). Blood samples were collected before and after intervention to analyse plasma levels of fHb and NO consumption. Endothelium-dependent relaxation was assessed in left internal mammary artery (LIMA) rings harvested before chest closure. Peripheral artery tonometry was assessed after intervention.
Transfusions with SBC increased plasma fHb (p<0.05). Transfusions of ASB resulted in higher plasma fHb compared to SBC (p<0.01). fHb concentrations directly correlated with NO consumption (r=0.65, p<0.001). Maximal endothelium-dependent relaxation in LIMA was significantly attenuated in SBC and ASB patients compared to control (15.2±3.1% vs 21.1±2.5% vs 43±5.0% respectively; p<0.01). Significant correlations were identified between the aortic pressure wave velocity, plasma fHb concentration and NO consumption (p<0.01).
Intraoperative blood transfusions and particularly autologous salvaged blood impair endothelium-dependent relaxation through NO scavenging by fHb. These findings obtained in vitro and in vivo provide new insights into the adverse relation between blood transfusions and patient outcome.
溶血产物游离血红蛋白（fHb）会降低一氧化氮（NO）的生物利用度。本研究旨在确定不同输血方式是否会导致接受冠状动脉旁路移植术（CABG）的患者循环中fHb水平升高以及NO消耗增加，从而影响动脉NO依赖性血流。
95例连续接受择期CABG手术的患者根据手术期间的输血需求前瞻性地分为四组：储存血细胞（SBC，21例）、术中自体回收血（ASB，25例）、SBC和ASB（22例）、未输血（对照组，27例）。在干预前后采集血样，分析血浆fHb水平和NO消耗情况。在关胸之前采集左乳内动脉（LIMA）环，评估内皮依赖性舒张功能。干预后评估外周动脉张力测定。
输注SBC会使血浆fHb升高（p<0.05）。与SBC相比，输注ASB导致更高的血浆fHb水平（p<0.01）。fHb浓度与NO消耗直接相关（r=0.65，p<0.001）。与对照组相比，SBC和ASB患者LIMA中的最大内皮依赖性舒张功能明显减弱（分别为15.2±3.1% vs 21.1±2.5% vs 43±5.0%；p<0.0l）。在主动脉压力波速度、血浆fHb浓度和NO消耗之间发现了显著相关性（p<0.01）。
术中输血，尤其是自体回收血，通过fHb清除NO损害内皮依赖性舒张功能。这些在体外和体内获得的发现为输血与患者预后之间的不良关系提供了新的见解。
