Background
Methods
National Inpatient Sample of 2014
Availability of data and materials
SEH case identification
Literature review for risk factors and spine surgery case selection
Statistical methods and data analyses
Results
Spine surgery and SEH case estimation
SEH risk factors suggested by recent research
Authors | Year | Incidence (cases/total population) | Risk factors | P-value |
---|---|---|---|---|
Kou et al. [27] | 2002 | NA | Multilevel procedure | 0.037 |
Anno et al. [28] | 2019 | 0.42% (14/3371) | Presence of preoperative coagulopathy | < 0.001 |
Cervical: 0.47% (4/856) | Age | NA | ||
Thoracic: 0.60% (2/332) | Multilevel procedure | NA | ||
Lumbar: 0.37% (8/2183) | Scar tissue due to previous spinal surgery | NA | ||
Heparinization | NA | |||
Vessel damage | NA | |||
Kebaish et al. [29] | 2004 | 0.2% | NA | NA |
Yamada et al. [30] | 2015 | 0.39% (32/8250) | ≥ 50 mmHg increase in blood pressure after extubation | 0.03 |
Obesity | 0.018 | |||
Agnelli et al. [31] | 1999 | 0% (0/15) | ||
Gerlach et al. [32] | 2004 | 0.7% (13/1954) | Thrombocytopenia | NA |
Anticoagulant use | NA | |||
Antiplatelet agent use | NA | |||
Alcohol consumption | NA | |||
Coagulopathy | NA | |||
Malignancy | NA | |||
Uribe et al. [33] | 2003 | 0.22% (9/4018) | Thrombocytopenia | NA |
Coagulation factor deficiency | NA | |||
Medications that predispose to bleeding | NA | |||
Previous surgery with attendant scarring at the site of epidural hematoma | NA | |||
Diabetes | ||||
Kim et al. [34] | 2019 | 23.6% (94/304; diagnosed by MRI) | Anticoagulant use | < 0.001 |
1.97% (6/304; hematoma evacuation surgery) | Female sex | 0.012 | ||
Old age (> 70 years) | 0.025 | |||
Use of intraoperative water infusion pump | 0.003 | |||
Type of operation | 0.01 | |||
Ohba et al. [35] | 2017 | 0.468% (6/1282) | Hypertension | NA |
Age > 60 years | NA | |||
Anticoagulant use | NA | |||
Use of nonsteroidal anti-inflammatory drugs (NSAIDs) | NA | |||
Previous spine surgery | NA | |||
Multilevel procedure | NA | |||
Blood loss > 1 L | NA | |||
Infections | NA | |||
Goldstein et al. [36] | 2013 | 1.5% (8/529) | Use of nonsteroidal anti-inflammatory drugs (NSAIDs) | 0.24 |
Increase in Charlson Comorbidity Index | 0.003 | |||
Yi et al. [37] | 2006 | 0.28% (9/3270) | Coagulopathy | |
Anticoagulant use | ||||
Cancer | ||||
Thiele et al. [38] | 2008 | NA | Predisposed bleeding | NA |
Prolonged surgical time | NA | |||
Old age | NA | |||
Trauma | NA | |||
Knusel et al. [39] | 2019 | 0.27% (206/75,878) | Old age | NA |
Obesity (BMI > 35) | NA | |||
Transfusion | NA | |||
Multilevel procedure | NA | |||
Invasive procedure | NA | |||
Microscope use | NA |
Characteristics of cases
Characteristics | No SEH | SEH | Total |
---|---|---|---|
Number of Cases | 17,348 | 201 | 17,549 |
Age (mean (SD) in year) | 56.72 (15.12) | 59.08 (13.71) | 56.75 (15.11) |
Sex | |||
Male | 8730 | 90 | 8820 |
Female | 8618 | 111 | 8729 |
Total Medical Paymenta (mean (SD) in USD) | 2438 (2071) | 3028 (2099) | 2445 (2072) |
Duration of Hospital Stay (mean (SD) in days) | 13.41 (9.49) | 19.35 (11.66) | 13.48 (9.54) |
Insurance Types | |||
National Health Insurance | 16,278 | 185 | 16,463 |
Medical Aid & Veterans | 1070 | 16 | 1086 |
Spine Surgery Types (%) | |||
Lumbar | 12,381 (98.64) | 170(1.35) | 12,551 (100) |
Not Lumbar | 4967 (99.38) | 31 (0.62) | 4998 (100) |
Spine Surgery Approach (%) | |||
Anterior | 3918 (98.47) | 61 (1.53) | 3979 (100) |
Not Anterior | 13,430 (98.97) | 140 (1.03) | 13,570 (100) |
Infections | |||
No | 15,983 | 180 | 16,163 |
Yes | 1365 | 21 | 1386 |
Diabetes | |||
No | 15,629 | 177 | 15,806 |
Yes | 1719 | 24 | 1743 |
Hypertension | |||
No | 11,972 | 121 | 12,093 |
Yes | 5376 | 80 | 5456 |
Use of NSAIDs | |||
No | 803 | 2 | 805 |
Yes | 16,545 | 199 | 16,744 |
Invasive Proceduresb (%) | |||
No | 13,056 (98.89) | 146 (1.11) | 13,202 (100) |
Yes | 4292 (98.73) | 55 (1.27) | 4347 (100) |
Bleeding Factorsc | |||
No | 14,223 | 140 | 14,363 |
Yes | 3125 | 61 | 3186 |
Trauma | |||
No | 16,499 | 188 | 16,687 |
Yes | 849 | 13 | 862 |
Anticoagulant Use | |||
No | 15,090 | 178 | 15,268 |
Yes | 2258 | 23 | 2281 |
Surgery Hours | |||
0 < HR ≤ 2 | 17,149 | 187 | 17,336 |
Over 2 h | 199 | 14 | 213 |
Blood Loss | |||
No Loss | 14,526 | 135 | 14,661 |
0 < Loss ≤0.5 L | 1871 | 41 | 1912 |
Over 0.5 L | 951 | 25 | 976 |
Type of Hospitalsd (%) | |||
General Hospitals | 6371 (99.04) | 62 (0.96) | 6433 (100) |
Small Hospitals | 10,977 (98.93) | 139 (1.07) | 11,116 (100) |
Number of Beds in Hospitals (%) | |||
Beds ≤200 | 10,611 (98.99) | 108 (1.01) | 10,719 (100) |
More than 200 Beds | 6737 (98.64) | 93 (1.36) | 6830 (100) |
Location of Hospitals (%) | |||
Metropolitan area (Seoul) | 5066 (99.37) | 32 (0.63) | 5098 (100) |
Other Metropolitan areas | 8853 (99.05) | 86 (0.95) | 8939 (100) |
Rural Area | 3421 (97.63) | 83 (2.37) | 3504 (100) |
Total (cases) |
SEH risk factors
Variables | P-value* |
---|---|
Age | 0.03 |
Sex | 0.12‡ |
Total medical cost | 0.00 |
Duration of hospital stay | 0.00 |
Insurance types | 0.24† |
Spine surgery type: lumbar | 0.00 |
Spine surgery approach: anterior | 0.00 |
Infection | 0.18‡ |
Diabetes | 0.34† |
Hypertension | 0.01 |
Use of NSAIDs | 0.01 |
Invasive procedures | 0.39† |
Bleeding factors | 0.00 |
Trauma | 0.31† |
Anticoagulant use | 0.51† |
Surgical time: > 2 h | 0.00 |
Blood loss: > 0.5 L | 0.00 |
Type of hospital: small hospitals | 0.09‡ |
Number of hospital beds: > 200 | 0.03 |
Location of hospital: rural area | 0.00 |
Risk factors | P > |z|* | OR (95% CI) |
---|---|---|
Spine surgery approach: anterior | 0.03 | 0.43 (0.20–0.90) |
Spine surgery type: lumbar | 0.01 | 1.75 (1.15–2.65) |
Blood loss: > 0.5 L | 0.00 | 2.11 (1.31–3.41) |
Surgical time: > 2 h | 0.00 | 7.22 (3.82–13.67) |
Hypertension | 0.03 | 1.41 (1.04–1.90) |
Use of NSAIDs | 0.01 | 7.30 (1.70–31.44) |
Bleeding factors | 0.00 | 1.92 (1.41–2.62) |
Anticoagulant use | 0.08 | 0.66 (0.42–1.05) |
Type of hospital: small hospitalsa | 0.03 | 1.48 (1.05–2.08) |
Location of hospital: rural area | 0.00 | 3.11 (2.32–4.18) |