Principles of office anesthesia: part I. Infiltrative anesthesia.

The use of effective analgesia is vital for any office procedure in which pain may be inflicted. The ideal anesthetic achieves 100 percent analgesia in a short period of time, works on intact or nonintact skin without systemic side effects, and invokes neither pain nor toxicity. Because no single agent meets all of these criteria, the physician must choose from the available armamentarium based on the anesthetic properties that are most desired. Infiltrative anesthetics are frequently chosen because of their proven safety record, low cost, ease of storage, widespread availability, and rapid onset of action. Allergy to local injectable anesthetics is rare, and when it occurs it is often secondary to the preservative in multidose vials. Anesthesia can be prolonged with the addition of epinephrine or the use of longer-acting agents. Buffering the local anesthetic with bicarbonate, warming the solution, and injecting slowly can minimize the pain of anesthetic injection. Complications are rare but include central nervous system and cardiovascular toxicity, or extreme vasoconstriction in an end organ, if epinephrine is used.