| Events | Number | % |
| Acute renal impairment within 30 days of surgery. | 8 | 27.6 |
| Re-operation for bleeding/tamponade during day 0 | 3 | 10.3 |
| Stroke | 3 | 10.3 |
| Persistent coma for >24 hours | 2 | 6.9 |