Table 1.
Patient characteristics
| High concentration group | Low concentration group | Placebo infusion group | p value | |
|---|---|---|---|---|
| Number | 28 | 32 | 33 | |
| Age (years) | 61 (57–64) | 63 (60–67) | 63 (60–66) | 0.58 |
| Sex (female/male) | 13/15 | 14/18 | 17/16 | 0.82 |
| Height (cm) | 169 (165–172) | 169 (167–172) | 170 (167–174) | 0.76 |
| Weight (kg) | 91 (84–98) | 92 (86–99) | 90 (83–96) | 0.83 |
| Body mass index (kg/m2) | 32 (30–34) | 32 (30–34) | 31 (29–33) | 0.63 |
| ASA status I/II/III | 2/12/14 | 0/13/19 | 2/21/10 | 0.12 |
| Surgery duration (minutes) | 100 (94–106) | 98 (92–103) | 97 (92–102) | 0.84 |
Data are presented as mean (95% confidence interval) or absolute number as appropriate. High concentration group, infusion of ropivacaine 0.2%; low concentration group, infusion of ropivacaine 0.1%; placebo infusion group, infusion of normal saline 0.9%; ASA = American Society of Anesthesiologists.