Table 9.
Top 15 keywords ranked by frequency and sigma.
| Rank | Keywords | Frequency | Keywords | Sigma |
|---|---|---|---|---|
| 1 | Cardiac surgery | 619 | Cardiopulmonary bypass | 6.26 |
| 2 | Surgery | 466 | Neuron specific enolase | 2.25 |
| 3 | Cardiopulmonary bypass | 430 | Coronary artery bypass | 2.05 |
| 4 | Outcome | 357 | Off pump | 1.9 |
| 5 | Risk factor | 302 | On pump | 1.74 |
| 6 | Dysfunction | 275 | Inflammatory response | 1.64 |
| 7 | Risk | 267 | Hypothermic circulatory arrest | 1.56 |
| 8 | Alzheimer's disease | 256 | Damage | 1.5 |
| 9 | Mortality | 240 | Stroke | 1.41 |
| 10 | Disease | 236 | Beating heart | 1.4 |
| 11 | Brain | 213 | Marker | 1.37 |
| 12 | Elderly patient | 196 | Performance | 1.37 |
| 13 | Association | 189 | Cerebral blood flow | 1.33 |
| 14 | Postoperative delirium | 180 | Release | 1.32 |
| 15 | Injury | 177 | Cerebrospinal fluid | 1.31 |