Patient and intervention characteristics and general outcome parameters
| Superficial (n=15) | Intermediate (n=15) | Deep (n=15) | P value* | |
| Sex, n (%) | 0.90 | |||
| Female | 5 (33%) | 4 (27%) | 4 (27%) | |
| Male | 10 (67%) | 11 (73%) | 11 (73%) | |
| Median age in years (IQR) | 70.00 (64.00, 78.00) | 73.00 (65.00, 77.00) | 70.00 (62.00, 74.00) | 0.37 |
| Mean height in cm (SD) | 170.07 (8.12) | 169.00 (6.71) | 174.27 (6.24) | 0.11 |
| Mean weight in kg (SD) | 81.07 (17.18) | 77.60 (10.29) | 79.00 (12.58) | 0.78 |
| ASA score, n (%) | ||||
| 2 | 6 (40%) | 6 (40%) | 5 (33%) | 0.88 |
| 3 | 9 (60%) | 8 (53%) | 9 (60%) | |
| 4 | 0 (0%) | 1 (7%) | 1 (7%) | |
| Height of carotid bifurcation, n (%) | ||||
| 2 | 0 (0%) | 0 (0%) | 1 (7%) | 0.12 |
| 3 | 4 (27%) | 8 (53%) | 2 (13%) | |
| 4 | 10 (67%) | 4 (27%) | 10 (67%) | |
| 5 | 1 (7%) | 3 (20%) | 2 (13%) | |
| Mean surgery duration in min (SD) | 86.33 (40.77) | 85.53 (25.69) | 93.13 (28.16) | 0.78 |
| Mean clamping time in min (SD) | 23.20 (11.99) | 23.67 (11.32) | 23.53 (15.33) | 0.99 |
| Bradycardia, n (%) | 0 (0%) | 1 (7%) | 0 (0%) | 0.36 |
| Tachycardia, n (%) | 1 (7%) | 4 (27%) | 2 (13%) | 0.31 |
| Hypertension, n (%) | 8 (53%) | 5 (33%) | 8 (53%) | 0.45 |
| Hypotension, n (%) | 1 (7%) | 2 (13%) | 2 (13%) | 0.80 |
| Shunting, n (%) | 1 (7%) | 0 (0%) | 3 (20%) | 0.15 |
| Conversion to GA, n (%) | 0 (0%) | 0 (0%) | 0 (0%) | 1.00 |
| Mean fentanyl in µg (SD) | 186.67 (66.73) | 140.00 (68.66) | 160.00 (50.71) | 0.13 |
| Mean supplemental LA, ie, prilocaine in mL (SD) | 10.47 (8.17) | 3.60 (5.73) | 5.60 (5.89) | 0.02 |
| Highest postoperative VAS, n (%) | ||||
| 0 | 0 (0%) | 1 (7%) | 0 (0%) | 0.20 |
| 1 | 4 (27%) | 6 (40%) | 9 (60%) | |
| 3 | 9 (60%) | 5 (33%) | 4 (27%) | |
| 4 | 1 (7%) | 0 (0%) | 0 (0%) | |
| 5 | 1 (7%) | 3 (20%) | 0 (0%) | |
| 6 | 0 (0%) | 0 (0%) | 1 (7%) | |
| 7 | 0 (0%) | 0 (0%) | 1 (7%) | |
| Patient satisfaction, n (%) | ||||
| 1=very good | 2 (13%) | 1 (7%) | 1 (7%) | 0.80 |
| 2=good | 12 (80%) | 13 (87%) | 14 (93%) | |
| 3=acceptable | 1 (7%) | 1 (7%) | 0 (0%) | |
| 4=unacceptable | 0 (0%) | 0 (0%) | 0 (0%) | |
| Paresis of recurrent nerve, n (%) | 0 (0%) | 2 (13%) | 0 (0%) | 0.12 |
| Postoperative hoarseness, n (%) | 2 (13%) | 3 (20%) | 8 (53%) | 0.04 |
| Neurological complications, n (%)† | 3 (20%) | 1 (7%) | 0 (0%) | 0.15 |
*Analysis of variance (ANOVA) for continuous variables, Kruskal-Wallis test for non-normally distributed ordinal variables, Pearson’s χ2 test for categorical variables.
†Two patients with ipsilateral facial nerve paralysis, two patients with transient dysarthria; no long-term sequelae or ischemic lesions.
ASA, American Society of Anesthesiologists; GA, general anesthesia; LA, local anesthetic; VAS, Visual Analogue Scale.