External Ventricular Drain and Hemorrhage in Aneurysmal Subarachnoid Hemorrhage Patients on Dual Antiplatelet Therapy: A Retrospective Cohort Study

Neurosurgery. 2019 Feb 1;84(2):479-484. doi: 10.1093/neuros/nyy127.


Background: Stenting and flow diversion for aneurysmal sub arachnoid hemorrhage (aSAH) require the use of dual antiplatelet therapy (DAPT).

Objective: To investigate whether DAPT is associated with hemorrhagic complication following placement of external ventricular drains (EVD) in patients with aSAH.

Methods: Rates of radiographically identified hemorrhage associated with EVD placement were compared between patients who received DAPT for stenting or flow diversion, and patients who underwent microsurgical clipping or coiling and did not receive DAPT by way of a backward stepwise multivariate analysis.

Results: Four hundred forty-three patients were admitted for aSAH management. Two hundred ninety-eight patients required placement of an EVD. One hundred twenty patients (40%) were treated with stent-assisted coiling or flow diversion and required DAPT, while 178 patients (60%) were treated with coiling without stents or microsurgical clipping and did not receive DAPT. Forty-two (14%) cases of new hemorrhage along the EVD catheter were identified radiographically. Thirty-two of these hemorrhages occurred in patients on DAPT, while 10 occurred in patients without DAPT. After multivariate analysis, DAPT was significantly associated with radiographic hemorrhage [odds ratio: 4.92, 95% confidence interval: 2.45-9.91, P = .0001]. We did not observe an increased proportion of symptomatic hemorrhage in patients receiving DAPT (10 of 32 [31%]) vs those without (5 of 10 [50%]; P = .4508).

Conclusion: Patients with aSAH who receive stent-assisted coiling or flow diversion are at higher risk for radiographic hemorrhage associated with EVD placement. The timing between EVD placement and DAPT initiation does not appear to be of clinical significance. Stenting and flow diversion remain viable options for aSAH patients.

MeSH terms

  • Adult
  • Aged
  • Cerebral Hemorrhage / epidemiology*
  • Cerebral Hemorrhage / etiology
  • Cohort Studies
  • Combined Modality Therapy / adverse effects*
  • Combined Modality Therapy / methods
  • Drainage / adverse effects
  • Dual Anti-Platelet Therapy / adverse effects*
  • Dual Anti-Platelet Therapy / methods
  • Endovascular Procedures / adverse effects
  • Endovascular Procedures / methods
  • Female
  • Humans
  • Male
  • Middle Aged
  • Platelet Aggregation Inhibitors / adverse effects
  • Platelet Aggregation Inhibitors / therapeutic use
  • Postoperative Hemorrhage / epidemiology*
  • Postoperative Hemorrhage / etiology
  • Retrospective Studies
  • Stents / adverse effects
  • Subarachnoid Hemorrhage / therapy*


  • Platelet Aggregation Inhibitors