In nine males [28 years (standard deviation:6)], volar forearm skin blood flux normalized to maximum vasodilation (%SkBFmax) was assessed at control (CTRL) and sensory nerve blockade (EMLA) treated sites during the PORH response following 20-min of complete arm ischemia and during rapid LTH (33-42 °C, 1 °C·20 s-1, held for ~30-min + 20-min at 44 °C) before and after ischemia-reperfusion (IR) injury.
EMLA increased mean [95 % confidence-interval] PORH amplitude by 21%SkBFmax ([9,33]; p = 0.003), delayed time to peak by 111 s ([40,182]; p = 0.007) and increased area under the curve by 19,462%SkBFmax·s ([11,346,27,579]; p < 0.001) compared to CTRL. For LTH, EMLA delayed onset time by 76 s ([46,106]; p < 0.001) Pre-IR and by 46 s ([27,65]; p < 0.001) Post-IR compared to CTRL. Post-IR onset time was delayed for CTRL by 26 s ([8,43]; p = 0.007), but was not different for EMLA (p > 0.050) compared to Pre-IR. EMLA delayed time to initial peak by 24 s ([4,43]; p = 0.022, Main time effect) and it attenuated the initial peak by 27%SkBFmax ([12,43]; p = 0.002) Pre-IR and by 16%SkBFmax ([3,29]; p = 0.020) post-IR compared to CTRL. Post-IR, the initial peak was not different for CTRL (p > 0.050), but it was increased by 16%SkBFmax ([5,26]; p = 0.005) for EMLA compared to Pre-IR. Neither EMLA nor IR altered the steady-state heating plateau (all p > 0.050).
For the current model of IR injury, sensory nerves appear to have a negligible influence on the LTH response in non-glabrous forearm skin once vasodilation has been initiated.
在9名男性[28岁(标准差:6)]中,在完全臂缺血20分钟后的PORH反应和快速LTH(33-42°C,在缺血再灌注(IR)损伤之前和之后,1°C·20s-1,在44°C下保持〜30-min20-min)。
EMLA使平均[95%置信区间]PORH振幅增加21%SkBFmax([9,33];p=0.003),与CTRL相比,达到峰值的时间延迟了111s([40,182];p=0.007),曲线下面积增加了19,462%SkBFmax·s([11,346,27,579];p<0.001)。对于LTH来说,与CTRL相比,EMLA的发作时间延迟了76s([46,106];p<0.001)前IR和46s([27,65];p<0.001)后IR。CTRL的IR发作后时间延迟了26s([8,43];p=0.007),但与前IR相比,EMLA没有差异(p>0.050)。与CTRL相比,EMLA延迟至初始峰的时间24秒([4,43];p=0.022,主时间效应),并且它使初始峰在IR前衰减27%SkBFmax([12,43];p=0.002),在IR后衰减16%SkBFmax([3,29];p=0.020)。后红外光谱,CTRL的初始峰没有差异(p>0.050),但与前IR相比,EMLA的SkBFmax增加了16%([5,26];p=0.005)。EMLA和IR均未改变稳态加热平台(所有p>0.050)。
对于目前的红外损伤模型,一旦开始血管舒张,感觉神经似乎对无毛前臂皮肤的LTH反应的影响可以忽略不计。