Table 1 Characteristics of patients admitted to ICU according to ICU grade in Korea, August 2009 to September 2014
Characteristics | ICU bed-to-nurse gradeb | p-value | |||
|---|---|---|---|---|---|
Grade 1 | Grade 2 | Grade 3 | Grade 4 or above | ||
(n = 11,691) | (n = 5095) | (n = 6797) | (n = 4266) | ||
Age, years | 6.0 (5.5) | 7.4 (6.1) | 8.0 (6.1) | 10.5 (5.9) | < 0.01 |
Age, year, median (IQR) | 4 (0.9, 11) | 6 (0.9, 14) | 7 (1, 14) | 13 (5, 16) | < 0.01 |
Sex, male | 6323 (54.1) | 3024 (59.4) | 4143 (61.0) | 2663 (62.4) | < 0.01 |
Type of hospital | < 0.01 | ||||
 Tertiary hospital | 10,763 (92.1) | 3342 (65.6) | 4134 (60.8) | 338 (7.9) |  |
 General hospital | 928 (7.9) | 1752 (34.4) | 2650 (39.0) | 3700 (86.7) |  |
 Hospital | 0 (0.0) | 1 (0.0) | 13 (0.2) | 228 (5.3) |  |
ICU admission volumea | < 0.01 | ||||
 > 600 per year | 2962 (25.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) |  |
 100–600 per year | 8228 (70.4) | 1948 (38.2) | 1520 (22.4) | 28 (0.7) |  |
 < 100 per year | 501 (4.3) | 3147 (61.8) | 5277 (77.6) | 4238 (99.3) |  |
Region | < 0.01 | ||||
 Capital | 10,339 (88.4) | 1550 (30.4) | 877 (12.9) | 750 (17.6) |  |
 Metropolitan | 10 (0.1) | 1471 (28.9) | 3270 (48.1) | 596 (14.0) |  |
 Province | 1342 (11.5) | 2074 (40.7) | 2650 (39.0) | 2920 (68.4) |  |
Admission department | < 0.01 | ||||
 Surgical | 7773 (66.5) | 3011 (59.1) | 3099 (45.6) | 2162 (50.7) |  |
 Medical | 3918 (33.5) | 2084 (40.9) | 3698 (54.4) | 2104 (49.3) |  |
Primary diagnosis | < 0.01 | ||||
 Congenital anomaly | 5268 (45.1) | 1724 (33.8) | 857 (12.6) | 117 (2.7) |  |
 Injury | 314 (2.7) | 812 (15.9) | 1730 (25.5) | 1969 (46.2) |  |
 Neoplasms | 2164 (18.5) | 365 (7.2) | 405 (6.0) | 220 (5.2) |  |
 Respiratory | 560 (4.8) | 479 (9.4) | 1186 (17.4) | 642 (15.0) |  |
 Neurologic disease | 1024 (8.8) | 496 (9.7) | 671 (9.9) | 330 (7.7) |  |
 Circulatory disease | 1107 (9.5) | 399 (7.8) | 517 (7.6) | 156 (3.7) |  |
 Gastrointestinal disease | 287 (2.5) | 154 (3.0) | 282 (4.1) | 255 (6.0) |  |
 Not elsewhere classified | 80 (0.7) | 105 (2.1) | 360 (5.3) | 148 (3.5) |  |
 Infectious disease | 131 (1.1) | 130 (2.6) | 237 (3.5) | 97 (2.3) |  |
 Others | 756 (6.5) | 431 (8.5) | 552 (8.1) | 332 (7.8) |  |
Interventions for critical care | |||||
 Mechanical ventilation | 6610 (56.5) | 2582 (50.7) | 1920 (28.2) | 516 (12.1) | < 0.01 |
 Vasopressors | 2696 (23.1) | 1263 (24.8) | 977 (14.4) | 315 (7.4) | < 0.01 |
 ECMO | 142 (1.2) | 53 (1.0) | 58 (0.9) | 13 (0.3) | < 0.01 |
 Hemodialysis | 504 (4.3) | 110 (2.2) | 105 (1.5) | 40 (0.9) | < 0.01 |
 CPR | 382 (3.3) | 298 (5.8) | 404 (5.9) | 161 (3.8) | < 0.01 |