Comparison between spinal, combined spinal-epidural and continuous spinal anesthesias for hip surgeries in elderly patients. A retrospective study

Abstract

Background and Objectives - There are still many questions involving study designs, data analyses and samples size which regard to the demonstration of the benefits of regional anesthesia on patients outcome. Database analysis and data acquisition in general cost less and require less time as compared to large randomized controlled trials. This retrospective study compares continuous spinal anesthesia, combined spinal-epidural and single shot spinal anesthesia for hip surgery in elderly patients during a 4-year period, to determine possible advantages and disadvantages of the three techniques. Methods - Anesthetic records of 100 patients receiving spinal anesthesia (Group 1), 100 patients receiving combined spinal-epidural block (Group 2) and 100 patients receiving continuous spinal anesthesia (Group 3) over a 4-year period were analyzed. All blockades were performed with patients in the left lateral position. Evaluated parameters were: puncture success, highest level of anesthesia, lower limb motor block, quality of anesthesia, need for additional doses, failures incidence, paresthesia, post-dural puncture headache, cardiovascular changes, mental confusion and delirium, blood transfusion and mortality. Results - There were no significant differences among groups regarding gender, age, weight and height. Group 2 patients were shorter as compared to groups 1 and 3. Mean bupivacaine doses were: 15.30 mg in group 1, 23.68 mg in group 2 and 10.1 mg in group 3. They showed statistical significant differences between groups (p < 0.01). There were significant differences (p < 0.01) in cephalad dispersion between groups 1 and 2, 1 and 3 and 2 and 3, being lower with continuous spinal and higher with combined spinal-epidural anesthesia. All patients presented total motor block (Bromage score = 3). There were no significant differences in arterial hypotension, bradycardia, paresthesia and blood transfusion. Postoperative mental confusion was observed in 19 patients, with no difference between techniques. There was no difference in mortality in the first postoperative week and in the first postoperative month. Conclusions - Retrospective studies usually less and demand less time as compared to controlled studies. This retrospective study has shown that regional anesthesia techniques are related to a low mortality rate in the first postoperative month and to a low incidence of complications.