[Cesarian section and local anaesthesia: insufficient spread of spinal anaesthesia with hyperbaric bupivacaine 0.5%/5% glucose compared to hyperbaric bupivacaine 0.5%/8% glucose?].

In our hospital hyperbaric Carbostesin 0.5% (AstraZeneca) had been substituted by hyperbaric Bucain 0.5% (Curasan) and both drugs were believed to be identical in their actions.However, both local anaesthetics differ in the amount of glucose they contain. We report about three patients who underwent cesarian section under spinal anaesthesia. In two patients we observed an insufficient spread of spinal anaesthesia after administration of hyperbaric Bucain 0.5%. The third patient received the normally used combination of hyperbaric Carbostesin 0.5% and fentanyl and the subarachnoid block proceeded completely uneventfully. According to the literature the clinical efficacy of hyperbaric Carbostesin 0.5% and hyperbaric Bucain 0.5% should be identical and therefore a critical dilution of the Bucain should not have occurred because of the addition of fentanyl.