Background

There is a lack of data about the effects of remote ischemic postconditioning (RIPostC) on hypoxia-inducible factor-1α (HIF-1α) plasma levels after on-pump cardiac surgery (OPCS). This study aimed to measure the effects of RIPostC on postoperative HIF-1α plasma levels, cardiac markers and arterial oxygenation in patients undergoing OPCS.

Methods

This single-centre randomized, double blind, controlled trial, enrolled 70 patients (35 control and 35 RIPostC). RIPostC was performed by 3 cycles (5 min of ischemia followed by 5 min of reperfusion) administered in upper arm immediately after the pump period. The primary outcome was to measure HIF-1α plasma levels: before surgery (T0), and 2 h (T1), 8 h (T2), 24 h (T3), 36 h (T4) and 48 h (T5) after RIPostC. As secondary endpoint, Troponin T, CK-MB, CPK plasma levels and PaO₂/FiO₂ ratio were measured.

Results

HIF-1α plasma levels were increased at T1–T3 compared to T0 in both groups (P < 0.001). In the RIPostC group HIF-1α increased compared to the control group: differences between means (95% CI) were 0.034 (0.006–0.06) P = 0.019 at T1; 0.041 (0.013–0.069) P = 0.005 at T2; and 0.021 (0.001–0.042) P = 0.045 at T3. PaO₂/FiO₂ was higher in the RIPostC group than in the control group: at T3, T4 and T5. Moreover, Troponin T, CK-MB and CPK values decreased in the RIPostC group compared to the control group.

Conclusions

HIF-1α plasma levels increased in control patients during for at least 36 h after OPCS. RIPostC resulted in even higher HIF-1α levels during at least the first 24 h and improved arterial oxygenation and cardiac markers.

中文翻译：

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体外循环心脏手术中远程缺血后处理对 HIF-1α 等标志物的影响

背景

缺乏关于远程缺血后处理 (RIPostC) 对体外循环心脏手术 (OPCS) 后缺氧诱导因子-1α (HIF-1α) 血浆水平影响的数据。本研究旨在测量 RIPostC 对 OPCS 患者术后 HIF-1α 血浆水平、心脏标志物和动脉氧合的影响。

方法

这项单中心随机、双盲、对照试验招募了 70 名患者（35 名对照和 35 名 RIPostC）。在泵期后立即在上臂施用 3 个周期（缺血 5 分钟，然后再灌注 5 分钟）进行 RIPostC。主要结果是测量 HIF-1α 血浆水平：手术前（T0）和 RIPostC 后 2 小时（T1）、8 小时（T2）、24 小时（T3）、36 小时（T4）和 48 小时（T5） . 作为次要终点，测量了肌钙蛋白T、CK-MB、CPK血浆水平和P aO ₂ / F iO ₂比值。

结果

与 T0 相比，两组的 HIF-1α 血浆水平在 T1-T3 均增加（P  < 0.001）。在 RIPostC 组中，与对照组相比，HIF-1α 增加：平均值之间的差异 (95% CI) 在 T1 时为 0.034 (0.006–0.06) P  = 0.019；0.041 (0.013–0.069)在 T2 时P  = 0.005；和 0.021 (0.001–0.042) P  = 0.045 在 T3。RIPostC 组的P aO ₂ / F iO ₂高于对照组：在 T3、T4 和 T5。此外，与对照组相比，RIPostC 组的肌钙蛋白 T、CK-MB 和 CPK 值降低。

结论

在 OPCS 后至少 36 小时内，对照患者的 HIF-1α 血浆水平升高。RIPostC 至少在前 24 小时内导致更高的 HIF-1α 水平，并改善了动脉氧合和心脏标志物。