Abstract
This study was designed to investigate the effects of low-dose α-human atrial natriuretic peptide (α-hANP) on hemodynamics, urination and cerebral blood flow in ten patients after cardiac surgery. We assessed cerebral blood flow in the carotid siphon by means of transcranial Doppler sonography (TCD). We measured the peak systolic blood flow velocity (Vs), the end-diastolic blood flow velocity (Ved) and the mean blood flow velocity (Vm), and calculated the pulsatility index (PI) in the left carotid siphon using 2MHz transcranial Doppler ultrasound system. After baseline measurement, the α-hANP loading dosage was increased from 0.025 to 0.05μg·kg-1·min-1 every 60 minutes. Hemodynamics, urine volume, Vs, Ved, Vm and PI were measured at each last point. There were no significant changes in hemodynamics (heart rate, mean arterial pressure, central venous pressure, pulmonary artery wedge pressure, cardiac index, systemic vascular resistance index), Vs, Ved, Vm and PI. Urine volume significantly increased from the baseline (129±82ml·hr-1) to 238±101ml·hr-1 at the infusion rate of 0.05μg·kg-1·min-1. In conclusion, we demonstrated that low-dose α-hANP led to an increase of urination without changes of hemodynamics and cerebral blood flow in the patients after cardiac surgery.
