Traditional Versus Goal Directed Perioperative Fluid Therapy in High Risk Patients

无干预：Control

Standard monitoring. Initial optimization of fluid status is performed by pulse, BP and anaesthesiologist assessment with Ringer acetate. Followed by an infusion of 10ml/kg/t Ringer acetate. Urinary output and blood pressure is used as a surrogate parameter: the infusion rate is increased by a fall in blood pressure or urine output <0.5ml/kg/t. Bleeding replaced with HES 1:1, otherwise see table for fluid therapy page 9. Vasoactive agents (noradrenaline / phenylephrine) is given if the anesthesiologist considers this necessary. Postoperative give 1000ml Glucose 5%. HES or Ringer when low blood pressure, eventually noradrenaline as vasoactive agent.

实验性的：Goal directed fluid therapy

程序：Goal directed fluid therapy guided by LiDCOrapid

Standard monitoring. The patient is connected to the LiDCOrapid monitor via an arterial line placed in a.radialis. A bolus of 500 ml Ringer acetate is given before anesthesia. If the stroke volume (SV) increases more than 10%, repeat the procedure until the SV is not increasing. After that, induction of anesthesia.

Maintenance fluid is given as Ringer acetate 2ml/kg/t. Continuous monitoring of stroke volume variation (SVV). If SVV> 10%, give a fluid bolus 6ml/kg Ringer acetate. Repeat until SVV <10%. Bleeding is being replaced 1:1 with hydroxyethyl starch. SAG by bleeding >1000ml. By fall in blood pressure and SVV <10%, start vasoactive treatment with epinephrine. Postoperative is given Glucose 5% 80ml/h.

Postoperative complications

Length of hospital stay

Complications until discharge and readmission within 30 days

Mortality within 30 days and 3-month after surgery

Renal function

defined by RIFLE criteria

Vasoactive agents need

Difference in the number of patients in need of vasoactive agents, during surgery and in the postoperative period.