Villamaria Carole Y, Fries C Anton, Spencer Jerry R, Roth Mark, Davis Michael R
From the *Department of Surgery, University of Texas Health Science Center at San Antonio, San Antonio, TX; †59MDW/Science and Technology, Joint Base San Antonio, San Antonio, TX; ‡United States Army Institute of Surgical Research, Fort Sam Houston, TX; and §Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA.
Ann Plast Surg. 2014 May;72(5):594-8. doi: 10.1097/SAP.0000000000000021.
Devastating extremity injuries are prevalent but often survivable on the modern battlefield. These complex injuries require advanced methods of reconstruction, involving prolonged ischemic periods and reperfusion injury. Using our group's validated porcine model of gracilis myocutaneous flap transplantation, this study demonstrates that an interim perfusion of hydrogen sulfide (H2S) mitigates the effects of reperfusion injury in the setting of delayed restoration of blood flow.
A gracilis myocutaneous flap (200-400 g; surface area, 250 cm²) was procured from the hind limb of a Yorkshire swine (70-90 kg, n=16). The right external carotid artery and the internal jugular vein are the recipient axis. Group 1 (control, n = 6) underwent delayed anastomosis with a 3-hour ischemic period. Group 2 (n=10) underwent a similar delayed anastomosis with an interim perfusion of H2S during the ischemic period. The animals survived for 14 days. Systemic biomarker assays for skeletal muscle tissue injury (creatine kinase, lactate dehydrogenase, and aspartate transaminase) and proinflammatory markers (tumor necrosis factor α and interleukin 6) provide assessment of reperfusion injury at the cellular level.
The control animals (3 hours of ischemia with an interim perfusion of heparinized saline) demonstrated increased levels of injury biomarkers and proinflammatory cytokines compared with the animals receiving H2S infusion and identical ischemic interval. The control flaps had a mean creatine kinase level of 280³×10 U/L (±80×10³), compared with the H2S group, which had a mean of 99×10³ U/L (±14×10³; P=0.0007 at postoperative day 2). lactate dehydrogenase levels (mean) were 26×10³ U/L (±8×10³) versus 9×10³ U/L (±3×10³; P=0.0004) and aspartate transaminase levels (mean) were 1651 U/L (±324) versus (873 U/L [±279]; P=0.0013) for the control and treatment groups, respectively. Similarly, an intergroup difference in IL-6 was found, although not statistically significant. Tumor necrosis factor α levels (mean) were 93 pg/mL (±14) versus 39 pg/mL (±4; P=0.0013) for the control and treatment groups, respectively.
This study demonstrated the mitigating properties of H2S on reperfusion injury. Interim perfusion with H2S resulted in diminution of ischemia-dependent biomarkers after 3 hours of ischemia. Follow-up studies will translate these findings as an evolving method for reconstructing previously unreconstructable injuries.
严重的肢体损伤在现代战场上很常见，但往往可以存活下来。这些复杂的损伤需要先进的重建方法，这涉及到较长的缺血期和再灌注损伤。利用我们团队验证过的猪股薄肌皮瓣移植模型，本研究表明，在延迟恢复血流的情况下，硫化氢（H₂S）的临时灌注可减轻再灌注损伤的影响。
从约克夏猪（70 - 90千克，n = 16）的后肢获取一块股薄肌皮瓣（200 - 400克；表面积250平方厘米）。右侧颈外动脉和颈内静脉作为受区血管轴。第1组（对照组，n = 6）进行延迟吻合，缺血期为3小时。第2组（n = 10）进行类似的延迟吻合，在缺血期进行H₂S临时灌注。动物存活14天。对骨骼肌组织损伤（肌酸激酶、乳酸脱氢酶和天冬氨酸转氨酶）和促炎标志物（肿瘤坏死因子α和白细胞介素6）进行全身生物标志物检测，以在细胞水平评估再灌注损伤。
与接受H₂S输注且缺血间隔相同的动物相比，对照组动物（缺血3小时并临时灌注肝素化盐水）的损伤生物标志物和促炎细胞因子水平升高。对照组皮瓣的肌酸激酶平均水平为280³×10 U/L（±80×10³），而H₂S组平均为99×10³ U/L（±14×10³；术后第2天P = 0.0007）。对照组和治疗组的乳酸脱氢酶平均水平分别为26×10³ U/L（±8×10³）和9×10³ U/L（±3×10³；P = 0.0004），天冬氨酸转氨酶平均水平分别为1651 U/L（±324）和873 U/L（±279）；P = 0.0013）。同样，虽然白细胞介素6组间差异无统计学意义，但也发现了组间差异。对照组和治疗组的肿瘤坏死因子α平均水平分别为93 pg/mL（±14）和39 pg/mL（±4；P = 0.0013）。
本研究证明了H₂S对再灌注损伤的减轻作用。缺血3小时后，H₂S临时灌注可使缺血依赖性生物标志物减少。后续研究将把这些发现转化为一种用于重建以前无法重建损伤的不断发展的方法。
