Temporary arterial occlusion (TAO) as independent prognostic factor in unruptured aneurysm surgery: A cohort study

Temporary arterial occlusion (TAO) is a technique widely used in cerebrovascular surgery. However, few studies have evaluated the independent long-term effects of TAO or given detailed information about the complications during in-hospital stay.

This study aims to investigate the independent impact of TAO during unruptured intracranial aneurysm surgery on short and long-term outcomes.

The study included surgical elective patients diagnosed with unruptured aneurysm and indication of microsurgical treatment. Outcome assessment included occurrence of intra-operative (IOC) and post-operative (POC) complications, as well as Glasgow Outcome Scale (GOS) score 6 months after discharge.

114 patients were included and 36 were followed. TAO was associated with POC (OR = 2.08; CI 95% 1.12-3.96; p = 0.01). The group with TAO and intraoperative rupture (IOR) did not differ from the group with TAO without IOR in terms of POC (p = 0.65) and IOC (p = 0.78). IOR (p = 0.16) and number of occlusions (p = 0.23) did not change GOS, but the total time of occlusion was associated with neurologic worsening (p = 0.034) during follow-up. The TAO group had larger aneurysm size and higher frequency of irregular lesions, when compared to the entire study group. Aneurysm location was not associated with POC (p = 0.25), IOC (0.17) or GOS (p = 0.75).

The location of temporary clip placement and the number of clips did not influence the short- and long-term outcomes of patients with unruptured intracranial aneurysms. However, presence of temporary clips was associated with POC regardless of IOR occurrence and increased total time of occlusion was associated with poor outcomes after 6 months.