Introduction: The intracranial decompression increases the compliance, reduces the in-tracranial pressure and increases the infusion pressure tissue preservation. Our goal is to establish when and how to perform decompression craniectomy front of a complication of aneurysmal hemorrhage Subarachnoid or not rupture.

Material and methods: Review article by papers analysis in PubMed, Scientific Direct, through key-words, inclusion and exclusion criteria. Analysis of clinical manifestation of AcoA based on literature anatomic-clinical review and casuistic study.

Results: Were 144 craniotomy of 2011-2014 37 aneurysms, 22 ruptured, Hunt-Hess Rate: grade I 7 cases (32%) II 14 (64%) III 1 (4%) and Fisher: F 1 6 cases (27%) F2 3 (14%) F3 5 (23%), F4, 8 (36%), 15 cases unruptured. Average age 48, 30-40: 6 cases, 40-50: 13, 50-60: 14, greater than 60 > 4.

Conclusions: We cannot monitor all cases of difficulty of the covenants and Hospital. Hunt-Hess and high Fisher were the worst prognosis. Age does not. Complications resulting in craniectomy were bruises, ischemia, edema or associations, asymmetry and deviation from average greater than 0.5 cm line. The bifrontal and posterior fossa had no cases of complicated aneurysm in these areas. In conclusion, the decompressive craniectomy reduces intracranial hypertension with decreased morbidity and mortality. Not indicated craniectomias located the risk of ischemia on the lips and clinical worsening. Early surgery evolves with better results, lower number of deaths and strengthens the doctor-patient relationship. Monitoring of Intracranial Pressure is critical, especially those neighboring, where it decides not to perform the craniotomy immediately.