Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - The Effects of General Anesthesia on Human Skin Microcirculation Evaluated by Wavelet Transform.
AU - Landsverk, Svein Aslak
AU - Kvandal, Per
AU - Bernjak, Alan
AU - Stefanovska, Aneta
AU - Kirkeboen, Knut Arvid
PY - 2007/10
Y1 - 2007/10
N2 - BACKGROUND: Time-frequency analysis of the laser Doppler flowmetry signal, using wavelet transform, shows periodic oscillations at five characteristic frequencies related to the heart (0.6–2 Hz), respiration (0.15– 0.6 Hz), myogenic activity in the vessel wall (0.052– 0.15 Hz), sympathetic activity (0.021– 0.052 Hz), and very slow oscillations (0.0095– 0.021), which can be modulated by the endothelium-dependent vasodilator acetylcholine. We hypothesized that wavelet transform of laser Doppler flowmetry signals could detect changes in the microcirculation induced by general anesthesia, such as alterations in vasomotion and sympathetic activity. METHODS: Eleven patients undergoing faciomaxillary surgery were included. Skin microcirculation was measured on the lower forearm with laser Doppler flowmetry and iontophoresis with acetylcholine and sodium nitroprusside before and during general anesthesia with propofol, fentanyl, and midazolam. The laser Doppler flowmetry signals were analyzed using wavelet transform. RESULTS: There were significant reductions in spectral amplitudes in the 0.0095–0.021 (P < 0.01), the 0.021–0.052 (P < 0.001), and the 0.052–0.15 Hz frequency interval (P < 0.01) and a significant increase in the 0.15–0.6 Hz frequency interval. General anesthesia had no effect on the difference between acetylcholine and sodium nitroprusside on relative amplitudes in the 0.0095–0.021 Hz frequency interval (P < 0.001). CONCLUSION: General anesthesia reduces the oscillatory components of the perfusion signal related to sympathetic, myogenic activity and the component modulated by the endothelium. However, the iontophoretic data did not reveal a specific effect on the endothelium. The increase in the 0.15–0.6 Hz interval is related to the effect of mechanical ventilation.
AB - BACKGROUND: Time-frequency analysis of the laser Doppler flowmetry signal, using wavelet transform, shows periodic oscillations at five characteristic frequencies related to the heart (0.6–2 Hz), respiration (0.15– 0.6 Hz), myogenic activity in the vessel wall (0.052– 0.15 Hz), sympathetic activity (0.021– 0.052 Hz), and very slow oscillations (0.0095– 0.021), which can be modulated by the endothelium-dependent vasodilator acetylcholine. We hypothesized that wavelet transform of laser Doppler flowmetry signals could detect changes in the microcirculation induced by general anesthesia, such as alterations in vasomotion and sympathetic activity. METHODS: Eleven patients undergoing faciomaxillary surgery were included. Skin microcirculation was measured on the lower forearm with laser Doppler flowmetry and iontophoresis with acetylcholine and sodium nitroprusside before and during general anesthesia with propofol, fentanyl, and midazolam. The laser Doppler flowmetry signals were analyzed using wavelet transform. RESULTS: There were significant reductions in spectral amplitudes in the 0.0095–0.021 (P < 0.01), the 0.021–0.052 (P < 0.001), and the 0.052–0.15 Hz frequency interval (P < 0.01) and a significant increase in the 0.15–0.6 Hz frequency interval. General anesthesia had no effect on the difference between acetylcholine and sodium nitroprusside on relative amplitudes in the 0.0095–0.021 Hz frequency interval (P < 0.001). CONCLUSION: General anesthesia reduces the oscillatory components of the perfusion signal related to sympathetic, myogenic activity and the component modulated by the endothelium. However, the iontophoretic data did not reveal a specific effect on the endothelium. The increase in the 0.15–0.6 Hz interval is related to the effect of mechanical ventilation.
U2 - 10.1213/01.ane.0000281932.09660.96
DO - 10.1213/01.ane.0000281932.09660.96
M3 - Journal article
VL - 105
SP - 1012
EP - 1019
JO - Anesthesia and Analgesia
JF - Anesthesia and Analgesia
SN - 0003-2999
IS - 4
ER -