The invention provides a flushing system (1) configured to flush the pericardial cavity (PC) of a patient, wherein the system comprises: an infusion liquid outlet (4) to connect a first tube(20) having an infusion liquid lumen to guide a flow of infusion liquid from the system to the pericardial cavity, and an effusion liquid inlet (6) to connect to a second tube (21) having an effusion liquid lumen to guide the effusion liquid flow from the pericardial cavity to the system, a flow rate control system to control the flow rate of the infusion liquid flow at the infusion liquid outlet (4) on the basis of multiple sensor signals, wherein the flow rate control system comprises: a control unit (5) to provide a control signal on the basis of the sensor signals, and a pump device (3) to pump infusion liquid to the infusion liquid outlet (4) at an infusion liquid flow rate, wherein the infusion liquid flow rate is adjustable by the control signal of the control unit (5) and wherein the sensor signals registered by the control unit (5) comprise: an infusion liquid signal representative for the infusion liquid flow to the pericardial cavity, an effusion liquid signal representative for the effusion liquid flow rate from the pericardial cavity, a blood volume signal generated by a hematocrit sensor (12) representative for a blood loss flow rate in the effusion liquid from the pericardial cavity, and a pressure control signal representative for the pressure in the pericardial cavity generated by a pressure sensor positioned inside or in connection with the first tube (20), the second tube (21) or the pericardial cavity. The invention also provides a method of monitoring the blood loss volume or flow rate from the pericardium based on multiple sensor signals as well as, a method of treatment of postoperative cardiac patients in order to reduce the risk of cardiac tamponade, reduce post-operative blood loss and reduce the accumulation of blood and clots in the pericardial cavity,
