Arora Subodh, Pomposelli Frank, LoGerfo Frank W, Veves Aristidis
George Washington University Medical Center and Veterans Affairs Medical Center, Washington, DC, USA.
J Vasc Surg. 2002 Mar;35(3):501-5. doi: 10.1067/mva.2002.121126.
The purpose of this study was the examination of the effect of successful large vessel revascularization on the microcirculation of the neuroischemic diabetic foot.
We measured the cutaneous microvascular reactivity in the foot in 13 patients with diabetes with peripheral arterial disease and neuropathy (group DI) before and 4 to 6 weeks after successful lower extremity arterial revascularization. We also compared them with age-matched and sex-matched groups of 15 patients with diabetes and neuropathy, seven patients without neuropathy, and 12 healthy patients for control. We used single-point and laser Doppler scan imaging for the measurement of the foot skin vasodilatation in response to heating to 44 degrees C and to iontophoresis of 1% acetylcholine (endothelial-dependent response) and 1% sodium nitroprusside (endothelial-independent response).
The group DI response to heat increased from 289% +/- 90% before surgery (percent increase over baseline measured in volts) to 427% +/- 61% (P <.05) after surgery but was still comparable with the response of the patients with diabetes and neuropathy (318% +/- 51%) and lower than the responses of the patients without neuropathy (766% +/- 220%) and the healthy patients for control (891% +/- 121%; P <.0001). The group DI acetylcholine response also improved from 6% +/- 4% before surgery to 26% +/- 8% after surgery (P <.05) and was similar to the responses of patients with diabetes and neuropathy (18% +/- 3%) and patients without neuropathy (38% +/- 8%) but still lower when compared with the response of the patients for control (48% +/- 9%; P <.001). The sodium nitroprusside response for group DI improved from 10% +/- 4% to 29% +/- 9% (P <.05) and was similar to the responses of the neuropathic (25% +/- 9%), nonneuropathic (32% plus minus 6%), and control (40% +/- 5%) groups. The group DI neurovascular response, which depends on the healthy function of the C-fiber nociceptors, was similar at baseline (5% +/- 9%) and after surgery (14% +/- %10) and in the neuropathic group (33% +/- 21%), but it was dramatically reduced when compared with the nonneuropathic (110% +/- 40%) and control (198% +/- 54%) groups (P <.001).
Impaired vasodilation in the diabetic neuropathic lower extremity leads to functional ischemia, which improves considerably but is not completely corrected with successful bypass grafting surgery. Therefore, patients with diabetes and neuropathy may still be at high risk for the development of foot ulceration or the failure to have an existing ulcer heal despite adequate correction of large vessel blood flow.
本研究旨在探讨成功的大血管血运重建对神经缺血性糖尿病足微循环的影响。
我们测量了13例患有外周动脉疾病和神经病变的糖尿病患者（DI组）在成功进行下肢动脉血运重建术前及术后4至6周足部皮肤微血管反应性。我们还将他们与年龄和性别匹配的15例患有糖尿病和神经病变的患者、7例无神经病变的患者以及12例健康对照患者进行比较。我们使用单点和激光多普勒扫描成像来测量足部皮肤对加热至44摄氏度以及对1%乙酰胆碱（内皮依赖性反应）和1%硝普钠（非内皮依赖性反应）离子导入的血管舒张反应。
DI组对热的反应从术前的289%±90%（以伏特为单位的相对于基线的百分比增加）增加到术后的427%±61%（P<.05），但仍与患有糖尿病和神经病变的患者的反应（318%±51%）相当，且低于无神经病变的患者的反应（766%±220%）以及健康对照患者的反应（891%±121%；P<.0001）。DI组对乙酰胆碱的反应也从术前的6%±4%改善到术后的26%±8%（P<.05），与患有糖尿病和神经病变的患者的反应（18%±3%）以及无神经病变的患者的反应（38%±8%）相似，但与对照患者的反应（48%±9%）相比仍较低（P<.001）。DI组对硝普钠的反应从10%±4%改善到29%±9%（P<.05），与神经病变组（25%±9%）、非神经病变组（32%±6%）和对照组（40%±5%）的反应相似。DI组依赖于C纤维伤害感受器健康功能的神经血管反应在基线时（5%±9%）、术后（14%±10%）以及神经病变组（33%±21%）相似，但与非神经病变组（110%±40%）和对照组（198%±54%）相比显著降低（P<.001）。
糖尿病神经病变下肢的血管舒张功能受损导致功能性缺血，成功的搭桥手术可使其显著改善，但未完全纠正。因此，患有糖尿病和神经病变的患者尽管大血管血流得到充分纠正，仍可能面临足部溃疡发生或现有溃疡不愈合的高风险。
