Decreased neck mobility and postoperative complications.

the arterial pressure wave by simulating a non-linear three-element model of aortic input impedance.1,2 The tracking of changes in cardiac output is precise.3,4 We investigated the real time changes in hemodynamic variables after SGB in patients free of cardiovascular disease. The study group comprised 21 patients with peripheral facial palsy. A right SGB was induced in ten patients and a left SGB in 11 patients. Hemodynamic variables included blood pressure, stroke volume, cardiac output, heart rate and total peripheral resistance. After the subject had rested in the supine position for ten minutes, left or right SGB was induced with 6 mL of 1% mepivacaine hydrochloride using the paratracheal anterior technique with the needle aimed at the transverse process of the sixth cervical vertebra. Hemodynamic variables were measured for 30 min after SGB. SGB was successful in all patients. Stroke volume and cardiac output increased slightly but not significantly after left SGB. The average systolic blood pressure decreased by 13.6 mmHg 10–20 min after right SGB and the average mean blood pressure decreased by 6.9 mmHg 15 min after the block. The average stroke volume and cardiac output decreased by 9.4 mL and 0.790 L·min–1 respectively five to 30 min after the block (Figure). As a result, the total peripheral resistance increased at ten minutes and at 20–30 min after the block. The heart rate decreased slightly but the difference was not statistically significant. In conclusion, right SGB appears to have greater hemodynamic consequences than left SGB as assessed by a model of aortic input impedance. There is a possibility that right SGB may worsen cardiac function in patients who already have a cardiovascular compromise.