clinical and pharmacokinetic comparison of ropivacaine and bupivacaine for supraclavicular brachial plexus block in patients with chronic renal failure

Avoiding the hazards of general anesthesia and providing peripheral vasodilatation make brachial plexus block an ideal form of anesthesia for arterio-venous fistula [AVF] creation in patients with chronic renal failure [CRF]. Sixty ASA class III patients aged 17 to 61 years were randomized to receive 30 mL of either ropivacaine 0.25% [n = 30; group I] or bupivacaine 0.25% [n = 30; group II] via a supraclavicular brachial plexus block. Both groups were comparable as regards onset time of motor block as well as duration of sensory and motor block. However, the mean onset time of sensory block was more delayed in the ropivacaine group [P= 0.0025]. Free bupivacaine concentrations were less than those of ropivacaine at different interval times. There was significantly higher incidence of complications in bupivacaine group especially respiratory distress and Horner's syndrome. Therefore, these results suggest that ropivacaine 0.25% is a better local anesthetic than bupivacaine 0.25% for use in a supraclavicular approach for brachial plexus block in high-risk patients with CRF

Efeito de surfactantes na estabilidade de compostos de uso terapêutico / Surfactants effect on the stability of terapeutic use compounds

Foi realizada uma revisäo crítica da literatura a respeito da estabilidade de fármacos em presença de surfactantes. Os grupos funcionais envolvidos nas reaçöes de decomposiçäo dos fármacos foram usados para o desenvolvimento da discussäo. A análise global desses estudos indicou que o efeito de surfactantes pode ser usado no controle de velocidades e mecanismos de decomposiçäo de fármacos e para obter informaçöes específicas de características da reatividade desses compostos em seus sítios de açäo farmacológica