Nivel sensitivo calculado vs. observado en anestesia peridural con bupivacaína. Estudio de concordancia

objectives: this study was designed to evaluate the concordance between measured and estimated sensitive level after epidural anesthesia with bupivacaine 0.5% and to validate the equation routinarily used to calculate total dose volume. methods: prospective conformity concordance study. setting and participants: 77 patients, both gender, older than 17, scheduled for abdominal or lower limb surgery at san ignacio university hospital under epidural anesthesia with bupivacaine 0.5%. the total volume dose and the estimated sensitive level was calculated using the equation (7.8-(age x 0.03) x no. metameres) / 5, and 30 minutes after epidural dose administration the observed sensitive level was assessed. then estimated sensitive level and measured sensitive level were compared. results: the 95% agreement limits were calculated between measured sensitive level and estimated sensitive level. the mean difference was 2.23 levels and the limits were -2.39 and 6.84. 50% of patients had at least 2 levels upper than expected, and some people had 9 levels upper than estimated. conclusions: there is a poor agreement between expected vs. observed level using the equation to estimate bupivacaine 0.5% volume dose.