Brothers T E, Wakefield T W, Jacobs L A, Lindenauer S M
Department of Surgery, University of Michigan, Ann Arbor.
Surgery. 1993 Apr;113(4):433-7.
Augmentation of cutaneous blood flow by postganglionic lumbar sympathectomy may not reflect an increase in nutritive vascular supply to the dermal tissues. Transcutaneous oxygen tension (TcPO2) was compared with radionuclide microsphere determination of dermal microcirculation in a hind limb sympathectomy model in 20 dogs. After 90 minutes the TcPO2 was greater in the sympathectomized limbs than in the contralateral limbs (125 mm Hg versus 114 mm Hg, p < or = 0.05). In contrast, microsphere-determined paw dermal capillary flow declined in sympathectomized limbs (4.9 ml/min/100 gm versus 11.8 ml/min/100 gm, p < or = 0.05). Decreases in the TcPO2/venous PO2 ratio correlated with sympathectomy-induced increases in total limb blood flow (r = 0.60; p < or = 0.001), reflecting less efficient oxygen extraction. These observations confirm the lack of enhancement of tissue oxygen delivery by sympathectomy because of the associated dilation of cutaneous arteriovenous shunts.
节后腰交感神经切除术引起的皮肤血流量增加可能并不反映真皮组织营养血管供应的增加。在20只犬的后肢交感神经切除术模型中，将经皮氧分压（TcPO2）与放射性核素微球测定的真皮微循环进行了比较。90分钟后，交感神经切除侧肢体的TcPO2高于对侧肢体（125毫米汞柱对114毫米汞柱，p≤0.05）。相比之下，微球测定的交感神经切除侧肢体的爪部真皮毛细血管血流量下降（4.9毫升/分钟/100克对11.8毫升/分钟/100克，p≤0.05）。TcPO2/静脉氧分压比值的降低与交感神经切除术引起的肢体总血流量增加相关（r = 0.60；p≤0.001），反映出氧提取效率降低。这些观察结果证实，由于皮肤动静脉分流的相关扩张，交感神经切除术并未增强组织氧输送。
