Effects of fluid therapy following aneurysmal subarachnoid haemorrhage: a prospective clinical study

Blood transfusions and intravenous fluids are commonly employed as rescue therapy for delayed cerebral ischaemia following aneurysmal subarachnoid haemorrhage (aSAH). We sought to determine effects of various fluid supplements on clinical outcome in patients following aSAH. Clinical events and laboratory data of 160 aSAH patients were prospectively collected as part of 2 randomised controlled trials. Outcomes at discharge and at 6 months were measured with Glasgow Outcome Scale (GOS). Favourable outcome was defined as good recovery or moderate disability on GOS. All of the 160 patients received intravenous fluid supplements with crystalloids; 122 (76.3%) also received synthetic colloids (4% succinylated gelatine or 6% pentastarch). A higher daily dose of synthetic colloids for initial resuscitation seemed to be associated with more requirements for blood transfusions (p=0.003) and occurrence of vasospasm in poor-grade patients (p=0.081), but blood transfusions themselves were not associated with occurrence of vasospasm. Compared with patients not receiving synthetic colloids, those receiving synthetic colloids had increased haemodilution, elevated inflammatory profiles, and decreased duration and strength of intact cerebral autoregulation. Multivariate analyses identified that blood transfusions (odds ratio, OR 3.38, p=0.035) were associated with unfavourable outcome at discharge. Colloid fluids (OR 2.53/L/day, p=0.025) promoted unfavourable outcome at 6 months (OR 4.45, p=0.035), while crystalloids decreased unfavourable outcome (OR 0.27/L/day, p=0.005). Associations between synthetic colloids and crystalloids with GOS at 6 months were dose-related. Intravenous fluid therapy using synthetic colloids or blood transfusions may be associated with increased unfavourable outcome following aSAH.