Burr hole evacuation of chronic subdural haematomas followed by continuous inflow and outflow irrigation.

Chronic subdural haematomas are prone to recollect, increasing the risk of further complications and death. Burr hole evacuation followed by continuous irrigation of a Ringer solution into the remaining subdural cavity, allows remaining blood to be washed out and the brain to re-expand. This technique was compared with burr hole evacuation either without or with a passive drainage and craniotomy, respectively. Reformation of haematomas after continuous irrigation occurred in 2.6% (2/77); more than a twelve (32.6%; 15/46) and a nine (23.8%; 5/21) times rate reduction compared to burr hole evacuation without and with passive drainage, respectively. Compared to the craniotomy results, the rate dropped seventeen times (44.4%; 4/9). Expect from the two rebleedings in 77 haematomas operated on through burr holes followed by irrigation, all patients recovered including nine recurrent haematomas re-operated on by this method. Recurrent haematomas operated on through burr hole evacuation alone or with insertion of a passive drainage, recollected in 50% (2/4) and 33.3% (2/6). Similar rate after craniotomies was 11.1% (1/9). Neither infections nor deaths followed burr hole evacuation combined with continuous irrigation, whereas 5.3% (2/38) and 5.9% (1/17) suffered from empyema after burr hole evacuation alone or combined with a passive drainage, respectively. Five (9.1%) of these 55 patients died either from empyemas (three) or rebleedings (two). Recurrent haematomas evacuated through a craniotomy had no complications from infections. Compared to other methods, continuous irrigation reduces the need for re-operation significantly by preventing haematoma recurrence and empyema formation. Contrary to other surgical techniques, haematoma recurrence after second time surgery did not occur.