Table 1 The length of anesthesia was defined from the time that the anesthesiologists started the spinal anesthesia in the patients to the time when the patients were sent to the post-anesthesia care unit. The length of surgery was defined from the time of initial incision to the time of the closure of the skin. POD, postoperative delirium; ASA, American Society of Anesthesiologists; cm, centimeter; min, minute; kg, kilogram; ml, milliliter; SD, standard deviation; CSF, cerebrospinal fluid
Characteristics of participants. | ||
|---|---|---|
|  | POD(N = 51) | Non-POD(N = 396) |
Age (year), mean ± SD | 73.3 ± 6.5 | 72.2 ± 6.0 |
Male, n (%) | 23 (45.1) | 187 (47.3) |
Years of education, n (%) | ||
 0 | 4 (7.8) | 28 (7.1) |
 1–9 | 22 (43.1) | 168 (42.4) |
 10–13 | 12 (23.5) | 81 (20.5) |
 14–17 | 9 (17.6) | 65 (16.4) |
  > 17 | 6 (11.8) | 54 (13.6) |
Height (cm), mean ± SD | 163.2 ± 7.1 | 161.5 ± 6.3 |
Body weight (kg), mean ± SD | 67.4 ± 8.8 | 65.3 ± 8.7 |
BMI (kg/m 2), mean ± SD | 26.3 ± 3.4 | 25.1 ± 2.8 |
ASA class, n (%) | ||
 I | 9 (17.6) | 63 (15.9) |
 II | 30 (58.8) | 231 (58.3) |
 III | 12 (23.5) | 102 (25.8) |
Time of anesthesia (min), mean ± SD | 145.6 ± 19.2 | 143.2 ± 18.9 |
Time of surgery (min), mean ± SD | 110.3 ± 20.3 | 108.7 ± 19.1 |
Type of surgery | ||
 Total hip arthroplasty/replacement, n (%) | 30 (58.8) | 222 (56.1) |
 Total knee arthroplasty/replacement, n (%) | 21 (41.2) | 174 (43.9) |
 Estimated blood loss (ml), median and 25–75 percentile | 180 (125–230) | 170 (115–220) |
 Postoperative the highest CAM score, median and 25–75 percentile | 18 (15–27) |  |
 Postoperative the highest MDAS score, median and 25–75 percentile | 7 (5–11) |  |
 Postoperative the highest VAS score, median and 25–75 percentile | 3 (1–5) | 2 (1–3) |