Table 3.
Secondary Outcomes
| Variables | Placebo Group (n=178) | S-Ketamine Group (n=178) | RR, Difference or HR (95% CI)d | P value |
|---|---|---|---|---|
| Incidence of RP within 24 hours | 67 (37.6%) | 44 (24.7%) | RR = 0.66 (0.48, 0.90) | 0.010 |
| Onset time of RP (h)a | NE | NE | HR = 0.60 (0.41, 0.88) | 0.009 |
| MRPS (score) | 6 (3, 7) | 6 (3, 6) | D = 0 (0, 0) | 0.329 |
| NRS at resting (score) | ||||
| POD 1 AM | 2 (2, 4) | 2 (2, 4) | D = 0 (−1, 1) | 0.279 |
| POD 1 PM | 2 (2, 2) | 2 (2, 2) | D = 0 (−1, 1) | 0.480 |
| POD 2 AM | 2 (0, 2) | 2 (0, 2) | D = 0 (−1, 1) | 0.084 |
| POD 2 PM | 2 (0, 2) | 2 (0, 2) | D = 0 (−1, 1) | 0.082 |
| NRS during activity (score) | ||||
| POD 1 AM | 4 (4, 6) | 3 (3, 6) | D = −1 (−1, 0) | 0.011 |
| POD 1 PM | 4 (4, 6) | 3 (3, 6) | D = −1 (−1, 0) | 0.003 |
| POD 2 AM | 2 (2, 4) | 2 (2, 4) | D = 0 (0, 0) | 0.080 |
| POD 2 PM | 2 (2, 4) | 2 (2, 4) | D = 0 (0, 0) | 0.112 |
| NRS during physical therapy (score) | ||||
| POD 1 | 5 (5, 6) | 3 (3, 6) | D = −2 (−2, −1) | <0.001 |
| POD 2 | 3 (3, 6) | 3 (3, 6) | D = 0 (0, 0) | 0.744 |
| Time to first rescue analgesia (h) | 10 (8, 12) | 15 (14, 16) | HR = 0.77 (0.59, 0.99) | 0.046 |
| Rescue analgesic dosage (mg)b | ||||
| 0–12 hours | 0 (0, 11) | 0 (0, 11) | D = 0 (0, 0) | 0.610 |
| 12–24 hours | 0 (0, 0) | 0 (0, 0) | D = 0 (0, 0) | 0.436 |
| 24–48 hours | 0 (0, 0) | 0 (0, 0) | D = 0 (0, 0) | 0.095 |
| Timed Up and Go test (s)c | 8 (−4, 25) | 10 (−3, 30) | D = 3 (−2, 7) | 0.242 |
| Postoperative AROM (°) | 80 (70, 90) | 80 (65, 90) | D = 0 (−5, 0) | 0.426 |
| Postoperative PROM (°) | 96 (87, 110) | 95 (80, 110) | D = −2 (−5, 0) | 0.163 |
| QoR-15 (score)c | −10 (−10, −10) | −5 (−10, −5) | D = 5 (5, 5) | <0.001 |
| Time to discharge criteria (d) | 4 (3, 5) | 4 (3, 5) | D = 0 (−1, 1) | 0.468 |
| Hospital stays (d) | 6 (5, 7) | 6 (5, 7) | D = 0 (−1, 1) | 0.060 |
| Patient satisfaction (score) | 2 (2, 3) | 3 (3, 3) | D = 1 (1, 1) | <0.001 |
Notes: The data is displayed in the form of the median (IQR) and number of cases (percentage). aSince the incidence of rebound pain was below 50% in both the S-ketamine and placebo groups, the median time could not be calculated. bThe rescue analgesic dose consists of the bolus dose delivered by the PCIA device and the intramuscular administration of meperidine, necessitating conversion to oral morphine equivalents. cExpressed as the absolute difference from the baseline measurement on the first day following surgery. dRR, HR, and difference were not adjusted for covariates.
Abbreviations: MRPS, modified rebound pain score; POD, postoperative day; AROM, active range of motion; PROM, passive range of motion; QoR, quality of recovery; NE, not estimable.