title: Vasospasm following aneurysmal subarachnoid hemorrhage: Thrombocytopenia a marker.
abstract: BACKGROUND
  Symptomatic vasospasm (SV) is often seen after aneurysmal subarachnoid hemorrhage (aSAH). The pathophysiology suggests that platelets initiate the process and are consumed. This is likely to result in thrombocytopenia. The objective of this study was to find out if thrombocytopenia preceded or followed SV and to analyze the relationship between the two.
  
  
  METHODS
  The platelet counts of 74 patients were studied on day 1, 3, 5, 7, 9, 11, and 14 following aSAH. Clinical symptoms and raised velocities on transcranial Doppler were studied on the same days to determine SV. The relationship of platelet counts and SV were analyzed.
  
  
  RESULTS
  Thirty-nine (52.7%) patients developed SV. Platelet counts dropped on postictal day (PID) 3-7 and SV was commonly seen on PID 5-9. The median platelet counts were significantly lower in patients with SV when compared to those without SV. Platelet count <150,000/mm(3) on PID 1 and 7 had statistically significant association (P < 0.001) with SV. The odds ratio was 5.1, 6.9, and 5.1 on PID 5, 7, and 9, respectively, for patients with relative thrombocytopenia (P < 0.001).
  
  
  CONCLUSIONS
  There is a strong correlation between thrombocytopenia and SV. A platelet count < 150,000/mm(3) on PID 1 and 7 predicts presence of SV. The relative risk of developing SV is >5 times for a patient with relative thrombocytopenia especially on PID 5-9. Additionally, it appears that thrombocytopenia precedes vasospasm and may be an independent predictor. However, this requires further studies for validation.
authors.affiliation: Department of Neurosurgery, PGIMER, Chandigarh, India.
authors.forename: Ashish
authors.initials: A
authors.lastname: Aggarwal
authors.forename: Pravin
authors.initials: P
authors.lastname: Salunke
authors.forename: Harnarayan
authors.initials: H
authors.lastname: Singh
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Gupta
authors.forename: Rajesh
authors.initials: R
authors.lastname: Chhabra
authors.forename: Navneet
authors.initials: N
authors.lastname: Singla
authors.forename: Ashwani Kumar
authors.initials: AK
authors.lastname: Sachdeva
keywords: Subarachnoid hemorrhage; thrombocytopenia; vasospasm