Effect of alkalimized mepivacaine for epidural anesthesia on the skin temperature and skin blood flow: A mathematical analysis by simulation model
- 30 Downloads
The changes in skin blood flow after barbiturate injection are predictable based upon changes in skin temperature, assuming that these changes are followed by ramp function of the first-order system composed of blood vessel-tissue-skin. We applied this simulation model to epidural anesthesia, and investigated the analogy between theoretical and measured values using 2% alkalinized and nonalkalinized mepivacaine. During epidural anesthesia, a Laser Doppler flowmeter and a skin temperature probe were used to simultaneously measure skin blood flow and skin temperature. The onset time of increases in skin temperature and blood flow in the alkalinized group was shortened by one-fourth of that of the nonalkalinized group. In the nonalkalinized group, the pattern of changes in skin blood flow could not be predicted using the mathematical model. In the alkalinized group, however, the skin blood flow change was in accord with the theoretical values calculated from the skin temperature. These results indicate that the precise prediction of measured values by the simulation model is dependent on the speed of the sympathetic blockade. Conversely, the response to sympathetic nerve and blood vessels in different conditions can be assessed using this simulation model.
Key wordsEpidural anesthesia Alkalinized mepivacaine Skin blood flow Skin temperature Laser Doppler Mathematical model
Unable to display preview. Download preview PDF.
- 1.Konishi A, Muneyuki M (1983) Analysis of models of the skin blood flow from variation of skin temperature. Report of research result by Grant-in-Aid of science research expenses in 1982 (General research; B5648026)Google Scholar
- 2.Muneyuki M, Uesaka H, Kamba M (1981) Some mathematical models for transient phenomena in reference to anesthesia. Hiroshima J Anesth 17: 177–184.Google Scholar
- 4.Parnass SM, Curran MJA, Becker GL (1978) Incidence of hypotension associated with epidural anesthesia using alkalinized and nonalkalinized lidocaine for cesarean section. Anesth Analg 66: 1148–1150Google Scholar
- 6.Nakayama A (1985) Reaction adjusted body temperature. In: Nakagawa T (eds) Thermophysiology, 1st edn., Rikogaku, Tokyo, p 122Google Scholar
- 7.Burton AC, Edholm OG (1979) Man in cold environment. Hafner, New York, p 78Google Scholar
- 11.Nickel PM, Bromage PR, Sherrill DL (1986) Comparison of hydrochloride and carbonated salts of lidocaine for epidural analgesia. Reg Anesth 11: 62–67Google Scholar
- 14.Galindo A (1983) pH-adjusted local anesthetics: clinical experience. Reg Anesth 8: 35–36Google Scholar
- 15.Bromage PR, Burfoot MF, Crowell DE, Truant AP (1967) Quality of epidural blockade III: Carbonated local anesthetic solutions. Br J Anesth 39: 197–209Google Scholar