title: Safety of heparinization for cerebral aneurysm coiling soon after external ventriculostomy drain placement.
abstract: OBJECTIVE
  Our practice has been to heparinize patients for cerebral aneurysm coiling even after recent external ventriculostomy drain (EVD) placement. The current medical literature cites a 12.5% symptomatic hemorrhage rate with heparinization after recent EVD placement. We reviewed our experience to determine our level of safety with this practice.
  
  
  METHODS
  A search of our prospectively collected computerized aneurysm database revealed that from February 1998 to February 2004, 356 aneurysms were coiled, of which 119 patients had had recent EVD placement before coiling. During the same time period, 251 subarachnoid hemorrhage patients underwent EVD placement without coiling or heparinization. We reviewed the head computed tomographic scan reports and medical records to determine the incidence of EVD-related hemorrhage in heparinized patients compared with nonheparinized patients.
  
  
  RESULTS
  There was only 1 patient in the heparinized group who had a symptomatic EVD-related hemorrhage attributable to heparinization (0.8%) and 11 patients with asymptomatic EVD-related hemorrhage (9.2%). Among the nonheparinized patients, there were 3 patients who had symptomatic EVD-related hemorrhages (1.2%) and 22 patients with asymptomatic EVD-related hemorrhages (8.8%) (P = not significant for both symptomatic and asymptomatic EVD-related hemorrhages). The time interval between EVD placement and heparinization in the heparinized patient with symptomatic EVD-related hemorrhage was 0.5 day; the mean time interval in the heparinized patients with asymptomatic EVD-related hemorrhage was 0.8 day; and in the heparinized patients with no hemorrhage, it was 0.8 day. The peak activated prothrombin time of the heparinized patient with symptomatic EVD-related hemorrhage was >150 seconds, the mean peak activated prothrombin time of the heparinized patients with asymptomatic EVD-related hemorrhage was 73.1 seconds, and that of the heparinized patients with no hemorrhage was 90.3 seconds.
  
  
  CONCLUSIONS
  Heparinization for cerebral aneurysm coiling can be safely performed even after EVD placement within 24 hours, particularly if the activated prothrombin time is kept strictly controlled.
authors.affiliation: Endovascular Neurosurgery/Interventional Neuroradiology and Cerebrovascular Surgery, Neurosurgical Service, Massachusetts General Hospital, Harvard Medical School, Boston 02114, Massachusetts, USA.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Hoh
authors.forename: Raul G
authors.initials: RG
authors.lastname: Nogueira
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Ledezma
authors.forename: Johnny C
authors.initials: JC
authors.lastname: Pryor
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Ogilvy
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use*; D020099:Coated Materials, Biocompatible; D004322:Drainage / Q000379:methods; D005260:Female; D006493:Heparin / Q000627:therapeutic use*; D006801:Humans; D002532:Intracranial Aneurysm / Q000188:drug therapy* / Q000473:pathology / Q000523:psychology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D014696:Ventriculostomy / Q000379:methods*
chemical_list: D000925:Anticoagulants; D020099:Coated Materials, Biocompatible; D006493:Heparin