Raquianestesia limitada: uma nova abordagem em cirurgias anorretais benignas: ensaio clínico randomizado

Abstract

BACKGROUNG: High rates of postoperative urinary retention (POUR) caused by spinal anesthesia are the main determinant of delayed discharge in benign outpatient anorectal surgeries. The overall objective of the study was to evaluate the efficacy and safety of limited spinal anesthesia in benign outpatient anorectal surgeries compared to sedation associated with perineal blockages.METHODS: Randomized Clinical Trial involving 65 patients comparing two anesthetic techniques for benign outpatient anorectal surgeries: limited spinal anesthesia (LSA) (intervention group - IG) and sedation associated with perineal blocks (control group - CG). The limitation consisted of intense reduction of intrathecal bupivacaine. Patients, interviewers and statisticians were blinded; The primary endpoint was the efficacy of limited spinal anesthesia evaluated through the need for complementation and/or anesthesia conversion and visual analogue pain scale in the postoperative period and specifically at the first evacuation. The secondary endpoints were: the safety of limited spinal anesthesia evaluated by interfering anesthetic techniques used for hemodynamic repercussion, the incidence of side effects and interference anesthesia at outpatient discharge; and user satisfaction. RESULTS: No IG subjects needed anesthetic complementation, while 24.2% of the CG did (p = 0.003). The incidence of pain was low over time and similar in the groups - major pain and minor pain were, respectively, up to 18.8% and 25% (IG) and 6.1% and 30.3% (CG), p> 0.05. In the CG the means of mean arterial pressure (p <0.05 at 5, 10, 15, 20 minutes) were lower and the means of heart rate (p <0.05 at 45, 50, 55 minutes) were higher. The incidence of POUR did not differ between groups - approximately 3%, p = 1,181. However, it was lower compared to that of traditional spinal anesthesia found in the literature; in addition, there was neither delay in outpatient discharge nor unplanned hospital admission due to anesthesia. CONCLUSION: LSA presented satisfactory anesthetic and analgesic profiles. It was more effective and safer than sedation associated with perineal blockages due to lower incidence of anesthesia complementation and hemodynamic risk. Moreover, the incidence of POUR was lower than that of traditional spinal anesthesia in the literature, without delay in outpatient discharge.