THE REGIONAL ANESTHESIA LEARNING-CURVE - WHAT IS THE MINIMUM NUMBER OF EPIDURAL AND SPINAL BLOCKS TO REACH CONSISTENCY

Background and Objectives. Wide variability exists in the amount of re gional anesthesia practice to which residents are exposed during train ing. The number of attempts at various blocks before a trainee becomes proficient at performing these regional anesthetic techniques is not known. This study addresses the question: What is the minimum number o f blocks a resident must perform to reach consistency during training in these techniques? Methods. Every regional anesthetic technique atte mpted by all beginning CA-1 anesthesiology residents (n = 7) during th eir first 6 months of training (July 1993 to December 1993) were recor ded on a daily basis. Nonregional anesthetic techniques attempted were recorded for comparison. The objective measures used to define the de gree of success were obtaining cerebrospinal fluid during attempted sp inal anesthesia, subsequent anesthetic block during epidural placement , and detection of end-tidal carbon dioxide for endotracheal intubatio n. Results. An average of 77 +/- 9 epidural anesthetics, 44 +/- 6 spin al anesthetics, and 86 +/- 13 endotracheal intubations were attempted during the 6 months of training. The learning curves for each techniqu e are of similar shape. Residents show significant (P <.05) improvemen t over baseline after 20 spinal and 25 epidural anesthetics, but a 90% success rate is not reached and maintained until 45 spinal and 60 epi dural anesthetics are performed. Conclusions. Approximately 20-25 proc edures each are necessary before improvement in the techniques of spin al and epidural anesthesia is demonstrated by residents in training. I f a 90% success rate is desired, 45 and 60 attempts at spinal and epid ural anesthesia, respectively, may be necessary.