Changes of sympathetic activity during tooth extraction

Urinary VMA excretion was studied in 3 groups of young and healthy subjects, before and 2 h after a standard tooth extraction. Local anaesthesia was either a solution of lignocaine 2% (1st group, n = 17) or a mixture of lignocaine 2% with noradrenaline bitartrate, 1250 micrograms/100 ml, (2nd group, n = 13) or lignocaine 2% with adrenaline hydrochloride 1250 micrograms/100 ml (3rd group, n = 10). Mean VMA excretion rose from 3.6 +/- 2.8 to 6.7 +/- 4.6 mg/g creatinine, in the first group. In the 2nd group, the mean VMA excretion was 2.3 +/- 1.2 and rose to 6.2 +/- 2.8, whereas in the 3rd it rose from 2.3 +/- 0.92 to 8.3 +/- 7.6 mg/g creatinine. The increase of VMA excretion after the tooth extraction was of the same order in the 3 groups studied and was not affected by the addition of noradrenaline and adrenaline in the anaesthetic solution.