1Servicio de Medicina Intensiva, H.U. Torrejón, Servicio de Salud de Madrid, Madrid, Spain
2Servicio de Urgencias Médicas de Madrid-SUMMA112, Servicio de Salud de Madrid, Madrid, Spain
3Servicio de Cardiologia, H.U. Puerta de Hierro-Majadahonda, Servicio de Salud de Madrid, Madrid, Spain
© 2024 The Korean Society of Critical Care Medicine
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| Variable | Total | Pre-mNEWS2-Lab | Post-mNEWS2-Lab | Post-AI enhanced mNEWS2-Lab |
|---|---|---|---|---|
| Patients | 3,790 | 358 | 3,117 | 315 |
| Total clinical records | 45,780 | 3,120 | 42,660 | 3,916 |
| Critical events | 94 | 22 | 65 | 7 |
| Variable | β | Standard error | Wald | P-value | Exp(β) |
|---|---|---|---|---|---|
| SpO2 | 3.050 | 0.202 | 227.545 | <0.001 | 21.126 |
| Respiratory rate | 2.271 | 0.161 | 198.680 | <0.001 | 9.691 |
| Oxygen therapy | 1.970 | 0.124 | 252.206 | <0.001 | 7.169 |
| Blood pressure | 1.287 | 0.212 | 36.937 | <0.001 | 3.622 |
| Heart rate | 2.991 | 0.510 | 34.399 | <0.001 | 19.896 |
| Level of consciousness | 1.337 | 0.107 | 156.039 | <0.001 | 3.807 |
| Temperature | 1.635 | 0.269 | 37.003 | <0.001 | 5.131 |
| Laboratory | 1.417 | 0.418 | 11.499 | <0.001 | 4.124 |
| Variable | β | Standard error | Wald | P-value | Exp(β) | 95% CI |
|---|---|---|---|---|---|---|
| SpO2 | 3.106 | 0.339 | 84.004 | <0.001 | 22.328 | 11.492–43.381 |
| Respiratory rate | 2.228 | 0.242 | 84.585 | <0.001 | 9.277 | 5.771–14.914 |
| Oxygen therapy | 1.819 | 0.146 | 155.228 | <0.001 | 6.167 | 4.632–8.211 |
| Blood pressure | 2.346 | 0.365 | 41.412 | <0.001 | 10.444 | 5.111–21.338 |
| Heart rate | 3.818 | 0.886 | 18.550 | <0.001 | 45.499 | 8.008–258.529 |
| Level of consciousness | 1.288 | 0.171 | 56.492 | <0.001 | 3.625 | 2.591–5.072 |
| Model | AUROC | Precision (PPV) | Sensitivity | Specificity |
|---|---|---|---|---|
| Logistic regression | 0.85 | 0.82 | 0.78 | 0.87 |
| Decision trees | 0.88 | 0.85 | 0.81 | 0.89 |
| Neural networks | 0.92 | 0.90 | 0.88 | 0.91 |
| Ensemble models | Variable results depending on the combination of models and simulated data | |||
| Study phase | Patient | Critical events | Critical events incidence (%) | Relative risk vs. pre-implementation | Relative risk reduction (%) |
|---|---|---|---|---|---|
| Pre-implementation mNEWS2-Lab system | 358 | 22 | 6.15 | - | - |
| Post-implementation mNEWS2-Lab system | 3,117 | 67 | 2.15 | 0.35 | 65 |
| Post-implementation AI enhanced mNEWS2-Lab system | 315 | 5 | 1.59 | 0.26 | 74 |
| Risk level | MNEWS2-Lab score | Pre-MNEWS2-Lab | Post-MNEWS2-Lab | Post-AI enhanced mNEWS2-Lab |
|---|---|---|---|---|
| None | 0 | 52 (14.5) | 970 (31.1) |
125 (39.7) |
| Very low | 1–2 | 138 (38.6) | 1199 (38.5) |
88 (28.0) |
| Low | 3–4 | 112 (31.3) | 654 (21.0) |
67(21.3) |
| Intermediate | 5–6 or 3 in one item | 31 (8.7) | 196 (6.3) |
23 (7.3) |
| High | 7 or more | 25 (7.0) | 98 (3.2) |
12 (3.5) |
| Phase | Number of CEs | Total cost per CE (€) |
Total cost (€) | Annualized cost (€) |
Annual savings (€) |
|---|---|---|---|---|---|
| Pre-MNEWS2-Lab (1 mo) | 22 | 19,525.00 | 429,550.00 | 5,146,600.00 | - |
| Post-MNEWS2-Lab (3 yr) | 65 | 19,525.00 | 1,269,125.00 | 423,042.00 | 4,723,558.00 |
| Post-AI enhanced mNEWS2-Lab (4 mo) | 7 | 19,525.00 | 136,675.00 | 410,025.00 | 4,736,575.00 |
mNEWS2-Lab: modified National Early Warning Score 2 with Laboratory Parameters; AI: artificial intelligence.
SpO2: oxygen saturation as measured by pulse oximetry.
SpO2: oxygen saturation as measured by pulse oximetry.
AI: artificial intelligence; AUROC: area under the receiver operating characteristic curve; PPV: positive predictive value.
mNEWS2-Lab: modified National Early Warning Score 2 with Laboratory Parameters; AI: artificial intelligence. Statistical significance: P<0.001.
Values are presented as number (%). mNEWS2-Lab: modified National Early Warning Score 2 with Laboratory Parameters; AI: artificial intelligence. Statistical significance, P<0.001.
mNEWS2-Lab: modified National Early Warning Score 2 with Laboratory Parameters; CE: critical event; AI: artificial intelligence. Total cost per critical event: calculated as (5 days in ICU × €1933) + (10 days in general ward × €986) = €9,665.00 + €9,860.00 = €19,525; Annualized cost: for pre-MNEWS2-Lab, the 1-month cost is annualized by multiplying by 12. For post-MNEWS2-Lab, the total cost over 3 years is divided by 3. For post-AI enhancement MNEWS2-Lab, the 4-month cost is annualized by multiplying by 3. Annual savings: calculated by subtracting the annualized cost of each phase from the annualized cost of the pre-implementation phase.