Influence of Different Anesthetics on Skin Oxygenation Studied by Electron Paramagnetic Resonance in vivo

Abstract

The effects of two general anesthetics on skin oxygenation in mice are evaluated by electron paramagnetic resonance oximetry. Up to now no data on the effects of different anesthetics on skin oxygenation could be found. In this study animals were anesthetized with ketamine/xylazine or isoflurane, and partial pressure of oxygen (pO₂) in the skin, heart rate and hemoglobin oxygen saturation were followed as a function of time and inhaled oxygen concentration. The skin pO₂ significantly increased continuously for about 60 min in mice anesthetized with isoflurane and remained constant after that. During ketamine/xylazine anesthesia, the pO₂ in the skin only slightly decreased. The skin pO₂ increased with higher inspired oxygen concentrations for both anesthetics groups. When breathing 21% oxygen, mice anesthetized with isoflurane had two-fold higher pO₂ in the skin compared to mice anesthetized with ketamine/xylazine. The heart rate was significantly lower in animals anesthetized with ketamine/xylazine, while hemoglobin saturation was almost the same in both groups at all inhaled oxygen concentrations. These results show that the type of anesthesia is an important parameter that needs to be considered in experiments where skin pO₂ is followed.

The Choice of Anesthesia Influences Oxidative Energy Metabolism and Tissue Survival in Critically Ischemic Murine Skin

“…These parameters were not assessed in our study. Whereas Henke et al [1] reported normoxic arterial oxygen saturation for KX anesthesia, our results exhibiting hypoxia are supported by the findings of Abramovic et al [12]. Although KX combinations and ketamine alone have been used for anesthesia over decades [2,14], multiple shortcomings have been reported.…”

“…In previous studies, it has been reported that KX anesthesia causes an increase in heart rate and lowers arterial blood pressure and breath rate in rodents [1,2,6,9,[12][13][14][15][16]. These parameters were not assessed in our study.…”

“…Although KX combinations and ketamine alone have been used for anesthesia over decades [2,14], multiple shortcomings have been reported. Abramovic et al [12] reported reduced partial oxygen tension in the skin, and Brown et al reported metabolic changes influencing glucose metabolism. Others have claimed that KX and ketamine should be avoided for animal research dealing with lymphatic and liver tissue [17], endothelial cells, diabetes [18], and skin [12].…”

Non-contact multi-spectral imaging combined with thermography to determine physiological changes in perfusion during clinical interventions

“…Healthy skin has a high pO2 level (8-13 kPa) but in tumors or hypoxic wounds the pO2 level can fall to 0.7 kPa [6;15]. Another process that can influence the skin pO2 is anesthesia, different type of anesthetics influence the skin perfusion in different ways [1]. The LED controllers are tuned that all the wavelengths give the same intensity and the LEDs are arranged over the panel so the light is homogeneous distributed over the subject.…”

“…Healthy skin has a high pO2 level (8-13 kPa) but in tumors or hypoxic wounds the pO2 level can fall to 0.7 kPa [6;15]. Another process that can influence the skin pO2 is anesthesia, different type of anesthetics influence the skin perfusion in different ways [1]. …”