[Preloading with 500 ml of Hartmann's solution lessens the incidence and severity of hypotension and reduces the need for ephedrine after epidural anesthesia in ambulatory patients].

INTRODUCTION

Fluid preloading to prevent hypotension after epidural anesthesia has been widely questioned, although few studies have been performed in outpatients.

OBJECTIVE

To evaluate the incidence and severity of hypotension, and the need for vasoactive agents after epidural anesthesia in outpatients who did or did not receive fluid preloading.

PATIENTS AND METHODS

Forty patients under 55 years of age (ASA I and II) undergoing general surgery on an outpatient basis were assigned randomly to two groups of 20 according to whether they were to receive loading with Hartmann's solution or not before epidural anesthesia. All received a similar epidural dose of 2% mepivacaine. Hypotension was defined as a decrease of 20% in systolic or mean blood pressure in comparison with baseline, or absolute pressures of < 90 and 60 mmHg, respectively. Hypotension was treated with 5 mg boluses of ephedrine.

RESULTS

Fourteen patients in the non-preloading group and 5 in the preloading group developed hypotension (p < 0.05). Hypotensive episodes were fewer in patients receiving preloading fluids (0.5 +/- 1.2 versus 2.0 +/- 2.4; p < 0.05). The ephedrine dose required was higher in non-preloaded patients than in preloaded ones (10.0 +/- 12.2 versus 2.6 +/- 6.3 mg; p < 0.05). Time until presentation of hypotension was longer for non-preloaded patients.

CONCLUSIONS

For patients undergoing outpatient surgery, fluid preloading with 500 ml of Hartman's solution decreases both the incidence and severity of hypotension, as well as the need for vasoactive drugs after epidural anesthesia.