RESUMO
BACKGROUND AND OBJECTIVES: Wound infiltration with available local anesthetics generally provides analgesia for less than 8 hrs. The site 1 sodium-channel toxin neosaxitoxin (neoSTX) produced analgesia for over 24 hrs in animals and human volunteers. In this randomized, double-blind trial, we examined the postoperative course of patients undergoing laparoscopic cholecystectomy under a standardized general anesthesia with wound infiltration using either neoSTX or bupivacaine. We hypothesized that neoSTX would reduce pain compared with bupivacaine at 12 hrs postoperatively. METHODS: Patients received preincisional infiltration of laparoscope entry sites with 20 mL containing either neoSTX (total dose, 100 µg) or bupivacaine 0.25% (total dose, 50 mg). The primary outcome measure was the visual analog pain score at 12 hrs postoperatively. Secondary outcomes included repeated pain scores at rest and with movement,analgesic use, functional recovery, and adverse effects. Groups were compared using Mann-Whitney U tests for pain scores, Fisher exact test for proportions of patients with severe pain and complete analgesia, and Kaplan-Meier curves for time to full recovery. RESULTS: Among 137 subjects, 69 were randomized to neoSTX and 68 to bupivacaine. Median pain scores at rest and with movement 12 hrs postoperatively were lower in the neoSTX group compared with the bupivacaine group (P<0.01). Additional pain measures and recovery parameters also favored neoSTX. No serious adverse events occurred,and no adverse events were more frequent in the neoSTX group. CONCLUSIONS: NeoSTX shows promise as a long-acting local anesthetic. Future studies will examine dose response, combination formulations, and safety with dose escalation.
Assuntos
Analgesia , Anestesia Local , Bupivacaína/administração & dosagem , Colecistectomia Laparoscópica , Dor Pós-Operatória/prevenção & controle , Saxitoxina/análogos & derivados , Adulto , Analgesia/métodos , Anestesia Local/métodos , Bupivacaína/farmacocinética , Colecistectomia Laparoscópica/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Medição da Dor/métodos , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/metabolismo , Saxitoxina/administração & dosagem , Saxitoxina/farmacocinéticaRESUMO
Complex regional pain syndromes (CRPS; type 1, reflex sympathetic dystrophy, and type 2, causalgia) involve persistent pain, allodynia, and vasomotor signs. We conducted a prospective, randomized, single-blind trial of physical therapy (PT) and cognitive-behavioral treatment for children and adolescents with CRPS. Children 8 to 17 years of age (n = 28) were randomly assigned to either group A (PT once per week for 6 weeks) or group B (PT 3 times per week for 6 weeks). Both groups received 6 sessions of cognitive-behavioral treatment. Assessments of pain and function were repeated at two follow-up time periods. Outcomes were compared at the three time points through the use of parametric or nonparametric analysis of variance and post hoc tests. All five measures of pain and function improved significantly in both groups after treatment, with sustained benefit evident in the majority of patients at long-term follow-up. Recurrent episodes were reported in 50% of patients, and 10 patients eventually received sympathetic blockade. Most children with CRPS showed reduced pain and improved function with a noninvasive rehabilitative treatment approach. Long-term functional outcomes were also very good.