World Journal of Emergency Medicine ›› 2023, Vol. 14 ›› Issue (2): 96-105.doi: 10.5847/wjem.j.1920-8642.2023.016
• Original Articles • Previous Articles Next Articles
Ahmed Faidh Ramzee1, Ayman El-Menyar2,3(), Mohammad Asim2, Ahad Kanbar1, Khalid Ahmed1, Bahaa Daoud1, Saji Mathradikkal1, Ahmad Kloub1, Hassan Al-Thani1, Sandro Rizoli1
Received:
2022-05-29
Online:
2023-03-03
Published:
2023-03-01
Contact:
Ayman El-Menyar
E-mail:aymanco65@yahoo.com
Ahmed Faidh Ramzee, Ayman El-Menyar, Mohammad Asim, Ahad Kanbar, Khalid Ahmed, Bahaa Daoud, Saji Mathradikkal, Ahmad Kloub, Hassan Al-Thani, Sandro Rizoli. The impact of emergency department length of stay on the outcomes of trauma patients requiring hospitalization: a retrospective observational study[J]. World Journal of Emergency Medicine, 2023, 14(2): 96-105.
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URL: http://wjem.com.cn/EN/10.5847/wjem.j.1920-8642.2023.016
Table 1.
Patients demographics, clinical characteristics and injury severity based on emergency department length of stay (n=7,026)
Variables | <4 h (n=1,628) | 4-12 h (n=3,561) | 12-24 h (n=1,205) | >24 h (n=632) | P-value |
---|---|---|---|---|---|
Age, years | 29.4±16.2 | 31.9±15.4 | 34.5±15.2 | 35.9±15.2 | 0.001 |
Males | 1,467 (90.1%) | 3,246 (91.2%) | 1,068 (88.6%) | 561 (88.8%) | 0.030 |
EMS time, min | 66 (50-81) | 69 (54-88) | 72 (55-91) | 69 (54-86) | 0.001 |
Mode of transportation | |||||
Ground ambulance | 1,393 (85.6%) | 2,972 (83.5%) | 1,032 (85.9%) | 525 (83.2%) | 0.001 |
Helicopter | 171 (10.5%) | 339 (9.5%) | 76 (6.3%) | 55 (8.7%) | |
Private vehicle | 64 (3.9%) | 248 (7.0%) | 94 (7.8%) | 51 (8.1%) | |
Trauma activation code | |||||
TTA-1 | 767 (50.0%) | 399 (12.1%) | 104 (10.2%) | 78 (14.4%) | 0.001 |
TTA-2 | 762 (49.7%) | 2,883 (87.4%) | 901 (88.2%) | 462 (85.1%) | |
TTA-3 | 5 (0.3%) | 18 (0.5%) | 17 (1.7%) | 3 (0.6%) | |
EDLOS, h | 2.4 (0.03-3.98) | 6.9 (4.0-12.0) | 16.2 (12.5-23.9) | 33.8 (24.0-724.8) | 0.001 |
Emergency department disposition | |||||
Operating room | 594 (36.5%) | 474 (13.3%) | 171 (14.2%) | 64 (10.1%) | 0.001 |
Intensive care unit | 526 (32.3%) | 694 (19.5%) | 181 (15.0%) | 125 (19.8%) | |
Surgical ward | 478 (29.4%) | 2,342 (65.8%) | 801 (66.5%) | 416 (65.8%) | |
Transferred to other facility | 4 (0.2%) | 7 (0.2%) | 3 (0.2%) | 1 (0.2%) | |
Home | 23 (1.4%) | 44 (1.2%) | 49 (4.1%) | 26 (4.1%) | |
Comorbidities and injury severity | |||||
Hypertension | 91 (5.6%) | 236 (6.6%) | 95 (7.9%) | 68 (10.8%) | 0.001 |
Diabetes mellitus | 116 (7.1%) | 256 (7.2%) | 87 (7.2%) | 56 (8.9%) | 0.490 |
Alcohol consumption | 140 (8.6%) | 258 (7.2%) | 78 (6.5%) | 50 (7.9%) | 0.160 |
Ethanol level, mmol/L | 39.1±20.2 | 37.9±20.6 | 38.4±19.3 | 32.4±18.4 | 0.230 |
Injury Severity Score | 14 (8-26) | 10 (5-16) | 10 (5-14) | 10 (6-17) | 0.001 |
Trauma Injury Severity Score | 0.89±0.20 | 0.97±0.10 | 0.98±0.08 | 0.97±0.07 | 0.001 |
Revised Trauma Score | 6.67±1.71 | 7.61±0.86 | 7.64±0.77 | 7.57±0.85 | 0.001 |
Head AIS | 4 (3-5) | 3 (3-4) | 3.2±0.9 | 3.3±0.8 | 0.001 |
Chest AIS | 3 (2-3) | 3 (2-3) | 2.6±0.7 | 2.7±0.7 | 0.001 |
Abdomen AIS | 3 (2-4) | 2 (2-3) | 2.3±0.8 | 2.4±0.9 | 0.001 |
Pelvic AIS | 2 (2-2) | 2 (2-2) | 2.1±0.4 | 2.2±0.5 | 0.020 |
Associated injuries | |||||
Head | 679 (41.7%) | 911 (25.6%) | 315 (26.1%) | 222 (35.1%) | 0.001 |
Chest | 631 (38.8%) | 1245 (35.0%) | 446 (37.0%) | 200 (31.6%) | 0.005 |
Abdomen | 476 (29.2%) | 565 (15.9%) | 190 (15.8%) | 114 (18.0%) | 0.001 |
Spine | 334 (20.5%) | 912 (25.6%) | 357 (29.6%) | 222 (35.1%) | 0.001 |
Upper extremities | 389 (23.9%) | 874 (24.5%) | 268 (22.2%) | 152 (24.1%) | 0.450 |
Lower extremities | 334 (20.5%) | 880 (24.7%) | 265 (22.0%) | 109 (17.2%) | 0.001 |
Table 2.
Prehospital and on-admission vital signs and laboratory findings based on emergency department length of stay
Variables | <4 h (n=1,628) | 4-12 h (n=3,561) | 12-24 h (n=1,205) | >24 h (n=632) | P-value |
---|---|---|---|---|---|
Heart rate at scene, beats per minute | 95.7±25.0 | 93.1±20.5 | 91.8±18.6 | 89.7±17.8 | 0.001 |
Systolic blood pressure at scene, mmHg | 129.4±26.7 | 129.8±21.8 | 131.1±23.2 | 133.2±23.4 | 0.009 |
Diastolic blood pressure at scene, mmHg | 81.9±21.5 | 81.5±18.3 | 82.2±19.3 | 83.1±18.2 | 0.340 |
Respiratory rate at scene, breath per minute | 19.2±6.1 | 18.9±4.5 | 18.6±3.7 | 18.2±3.1 | 0.001 |
GCS at scene | 15 (10-15) | 15 (15-15) | 15 (15-15) | 15 (15-15) | 0.001 |
Heart rate at ED, beats per minute | 98.5±24.8 | 90.6±18.9 | 88.6±17.5 | 87.8±16.6 | 0.001 |
Systolic blood pressure at ED, mmHg | 121.2±24.2 | 125.2±18.4 | 127.6±18.9 | 128.5±19.9 | 0.001 |
Diastolic blood pressure at ED, mmHg | 75.2±16.4 | 76.9±13.8 | 77.9±13.5 | 77.5±14.0 | 0.001 |
Respiratory rate at ED, breath per minute | 20.2±4.7 | 19.4±3.7 | 19.3±3.7 | 19.1±2.5 | 0.001 |
GCS at ED | 15 (4-15) | 15 (15-15) | 15 (15-15) | 15 (15-15) | 0.001 |
Shock index at ED | 0.86±0.36 | 0.74±0.22 | 0.71±0.19 | 0.70±0.21 | 0.001 |
Laboratory findings (n=3,633) | (n= 967) | (n=1,941) | (n=536) | (n=189) | 0.001 |
Lactate initial value, mmol/L (n=3,086) | 3.2±2.9 | 2.5±1.5 | 2.3±1.5 | 2.4±1.5 | 0.001 |
Lactate consecutive reading, mmol/L (n=1,198) | 2.9±2.3 | 2.3±1.7 | 2.0±1.3 | 2.0±1.5 | 0.001 |
Base deficit initial reading, mmol/L (n=2,751) | -4.6±5.0 | -2.1±3.5 | -1.3±2.9 | -1.7±2.9 | 0.001 |
Base deficit consecutive reading, mmol/L (n=805) | -5.9±5.6 | -3.2±3.7 | -2.2±3.1 | -3.1±3.9 | 0.001 |
Hemoglobin initial value, g/mL (n=3,508) | 12.7±2.3 | 13.6±1.9 | 13.8±1.8 | 13.5±2.0 | 0.001 |
Hemoglobin consecutive reading, g/mL (n=1,885) | 11.8±2.4 | 12.5±2.2 | 12.8±2.1 | 12.3±2.0 | 0.001 |
Myoglobin initial value, ng/mL (n=1,931) | 374 (15-9,372) | 306 (3-6,749) | 281 (13-5,163) | 246 (22-4,456) | 0.001 |
Troponin initial value, ng/L (n=2,011) | 10 (5.3-34.4) | 10 (5.0-11.3) | 10 (5.0-11.0) | 10 (4.2-10.0) | 0.001 |
Troponin consecutive reading, ng/L (n=724) | 19 (7.7-93.1) | 10.6 (5.9-37.9) | 9.4 (6.1-28.3) | 10 (4.6-18.3) | 0.001 |
Table 3.
Complications and outcomes based on emergency department length of stay
Variables | <4 h (n=1,628) | 4-12 h (n=3,561) | 12-24 h (n=1,205) | >24 h (n=632) | P-value |
---|---|---|---|---|---|
Initial CT scan | 1,291 (79.3%) | 3,221 (90.5%) | 1,102 (91.5%) | 588 (93.0%) | 0.001 |
Number of CT scans in ED | 5 (1-9) | 5 (1-8) | 5 (1-7) | 5 (1-8) | 0.001 |
Plain X-ray | 1,386 (85.1%) | 3,155 (88.6%) | 1,053 (87.4%) | 571 (90.3%) | 0.001 |
FAST scan | 1,502 (92.3%) | 3,345 (93.9%) | 1,123 (93.2%) | 590 (93.4%) | 0.160 |
Blood transfusion | 602 (37.0%) | 523 (14.7%) | 125 (10.4%) | 83 (13.1%) | 0.001 |
Units of transfused blood | 5 (1-49) | 3 (1-73) | 3 (1-37) | 2 (1-25) | 0.001 |
Complications | |||||
Pneumonia | 113 (6.9%) | 74 (2.1%) | 28 (2.3%) | 17 (2.7%) | 0.001 |
Sepsis | 41 (2.5%) | 34 (1.0%) | 7 (0.6%) | 6 (0.9%) | 0.001 |
Organ failure | 7 (0.4%) | 5 (0.1%) | 2 (0.2%) | 0 (0.0%) | 0.090 |
ARDS | 34 (2.1%) | 22 (0.6%) | 6 (0.5%) | 3 (0.5%) | 0.001 |
ICU LOS, d | 5 (1-153) | 3 (1-90) | 3.5 (1-58) | 4 (1-123) | 0.001 |
Hospital LOS, d | 7 (1-214) | 4 (1-505) | 4 (1-158) | 6 (1-123) | 0.001 |
Ventilatory days | 4 (1-180) | 6 (1-100) | 6 (1-47) | 4 (1-62) | 0.040 |
In-hospital mortality | 159 (9.8%) | 63 (1.8%) | 19 (1.6%) | 7 (1.1%) | 0.001 |
Place of death | |||||
ICU | 145 (91.2%) | 62 (98.4%) | 17 (89.5%) | 6 (85.7%) | 0.010 |
Operating room | 13 (8.2%) | 0 (0.0%) | 1 (5.3%) | 0 (0.0%) | 0.010 |
Surgical wards | 1 (0.6%) | 1 (1.6%) | 1 (5.3%) | 1 (14.3%) | 0.010 |
Table 4.
Predictors of short emergency length of stay (EDLOS <4 h)
Predictors | Odds ratio | 95% confidence interval | P-value |
---|---|---|---|
Initial serum lactate value | 1.033 | 0.976-1.093 | 0.262 |
Initial base deficit value | 0.974 | 0.944-1.005 | 0.099 |
Initial blood hemoglobin level | 0.922 | 0.874-0.973 | 0.003 |
Age in years | 0.993 | 0.986-1.000 | 0.064 |
Gender (female) | 1.670 | 1.135-2.463 | 0.009 |
Injury Severity Score | 1.018 | 1.006-1.030 | 0.003 |
Glasgow Coma Score at the ED | 0.853 | 0.831-0.876 | 0.001 |
Shock index at the ED | 1.546 | 1.004-2.379 | 0.048 |
Blood transfusion | 1.477 | 1.118-1.952 | 0.006 |
Table 5.
Multivariate regression analysis for the predictors of mortality
Predictor | Odds ratio | 95% confidence interval | P-value |
---|---|---|---|
Age in years | 1.040 | 1.026-1.054 | 0.001 |
Gender (male vs. female) | 0.791 | 0.366-1.709 | 0.551 |
EMS transportation time | 1.326 | 0.900-1.955 | 0.154 |
EDLOS time in hours | 0.985 | 0.965-1.006 | 0.170 |
Injury Severity Score | 1.077 | 1.057-1.096 | 0.001 |
Shock index | 2.132 | 1.364-3.332 | 0.001 |
Head injury | 3.920 | 2.413-6.368 | 0.001 |
TTA-1 | 4.081 | 2.364-7.045 | 0.001 |
Blood transfusion (any) | 2.773 | 1.668-4.609 | 0.001 |
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