Cardiovascular and sympathetic responses to dental surgery with local anesthesia

We investigated changes in blood pressure and blood variables, including plasma catecholamines, serum glucose and insulin concentrations, during dental surgery. The study included 11 normotensive patients (age, 22.5+/-0.7 years) who underwent tooth extraction at Kyushu Dental College Hospital. Three to 7 days prior to dental surgery, blood pressure, pulse rate, and heart rate variability were measured every 30 min over 24 h. The low frequency (LF: 0.05 to 0.15 Hz) and high frequency (HF: 0.15 to 0.40 Hz) powers were calculated, and the ratio of LF to HF (LF/HF) and HF were used as indexes of sympathetic and parasympathetic activities, respectively. Lidocaine, 2% with epinephrine (1:80,000), was used as the local anesthetic for all patients. Systolic blood pressures significantly increased during dental surgery (+10.8+/-3.5 mmHg); however, this increase failed to correlate not only with baseline systolic blood pressure but with 24-h averaged blood pressures, LF/HF or HF. On the other hand, plasma epinephrine and norepinephrine concentrations increased during dental surgery, and peak values of these variables were obtained after local anesthesia and during tooth extraction, respectively. Serum glucose level increased after local anesthesia (control vs. local anesthesia: 5.16+/-0.11 vs. 5.62+/-0.10 mmol/l; p<0.01); however, plasma insulin concentrations did not change significantly. These results suggest that 1) ambulatory measurements of blood pressure and heart rate variability over 24 h cannot predict the responses of blood pressure during dental surgery, and that 2) administration of local anesthetic and tooth extraction activate sympathoadrenal outflow, resulting in an increase in serum glucose level in normotensive subjects.