Changes

There are a variety of drugs available to use for local analgesia/anaesthesia. They vary in duration of action, but all act in a similar way. Lipid solubility determines the potency of the agent, while the protein binding ability is thought to determine the duration of action. The preparation is also important, as some preprations cannot be used for certain blocks or in certain regions of the body, for example for epidurals, only preservative free preparations can be used.  

There are a variety of drugs available to use for local analgesia/anaesthesia. They vary in duration of action, but all act in a similar way. Lipid solubility determines the potency of the agent, while the protein binding ability is thought to determine the duration of action. The preparation is also important, as some preprations cannot be used for certain blocks or in certain regions of the body, for example for epidurals, only preservative free preparations can be used.  

Care should be taken when using local anaesthetic agents that doses are kept as low as possible to avoid toxicity problems.

Care should be taken when using local anaesthetic agents that doses are kept as low as possible to avoid toxicity problems. It is also important to take care when using agents with adrenaline in the preparation as this causes severe ''vasoconstriction'' which if used in a region with end artery supply for example, it may lead to necrosis of that area.