[Combined 3-in-1 sciatic block. Prilocaine 500 mg vs. 650 mg]

The objective of the study was to investigate the clinical effectiveness of increasing the dosage of prilocaine for a combined 3-in-1/sciatic nerve block from 500 to 650 mg (open study with 29 patients compared with 30 patients from a former study) and to validate these findings in a second stage (randomised study comparing two groups of 30 patients each). Not only was clinical effectiveness improved by increasing the dose to 650 mg, but methaemoglobinaemia and toxicity were not relevant problems. With the higher dosage, development of the block was slightly faster (onset and completion); there were fewer unsatisfactory blocks; and clinically relevant plasma levels of methaemoglobin did not occur.