Stress Response of Subarachnoid Hemorrhage to Cardiac Performance and Intravascular Volume Evaluated by the Pulse Contour Cardiac Output (PiCCO) System

The aim of this study was to investigate cardiac performance and volume status after subarachnoid hemorrhage (SAH). Hemodynamic and volumetric parameters including cardiac index (CL), intrathoracic blood volume index (ITBVI), and extravascular lung water index (EVLWI) were evaluated by single indicator transpulmonary thermodilution (PiCCO) from days 1 to 4 in 32 patients with SAH treated surgically or endovascularly within 24 hours. Higher CL and lower ITBVI values were observed after SAH. The mean value of Cl was 5.2 l/min/m2 on day 1, which gradually decreased to 3.4 l/min/m2 on day 4. The mean ITBVI value was 730 ml/m2 on day 1, which recovered to the reference range until day 4 by fluid administration aiming for normovolemia. Higher CL and lower ITBVI values were present in patients with poor clinical grade (WFNS grade IV, V) as compared with mild to moderate grade (I -Ill) (p < 0.05). Relationship between CL and SI were well correlated (r = 0.77, p < 0.0001). The results indicate that SAH predisposes patients to hyperdynamic and hypovolemic states associated with sympathetic hyperactivity, especially in patients with poor clinical grade. Bedside monitoring with the PiCCO system may be a powerful tool for the management of patients after SAH.