High concordance between expert anaesthetists' actions and advice of decision support system in achieving oxygen delivery targets in high-risk surgery patients.

Background: Goal-directed therapy has a secure place in perioperative care. Algorithms are based on Starling's law of the heart, notwithstanding that this does not numerically define volume or heart performance variables. These have been developed based on a Guytonian view of the circulation and are implemented in a computerized decision support system (Navigator™). We studied the feasibility and performance of the graphical display of the system in an intervention and a control group of patients undergoing major abdominal surgery.

Methods: Patients were randomized to either graphically (intervention) or numerically (control) guided administration of therapy. Goals were set and treatments and concordance with guidance noted, where applicable. Anaesthesia was provided by one of three experienced anaesthetists well acquainted with Navigator™. The primary objective was to determine whether the use of graphical display decision support more efficiently enables the achievement of oxygen delivery targets. This was quantitated as percentage time in the target zone and averaged standardized distance from the target centre.

Results: The mean percentage time in the target zone was 36.7% for control and 36.5% for intervention. The averaged standardized difference was 1.5 in control and 1.6 in intervention. There was no significant difference in fluid balances. There was a high level of concordance between decision support recommendation and anaesthetist action (84.3%).

Conclusions: In experienced hands, the addition of a graphical display for haemodynamic guidance resulted in a similar time in target and averaged standardized difference. The haemodynamic guidance system should be explored in a comparative study to anaesthesia management without guidance.