Preoperative optimisation of high risk patients

Several risk factors have been identified insurgical patients and attempts have been made to predict the outcome in such patients. Among these risk factors are oxygen delivery (DO2) and oxygen consumption (VO2) values. Several studies were conducted in which specific values for calculated DO2 and VO2 were used as criteria for strategies to improve outcome in different types of critically ill patients. We will review the rationale and evidence for this type of therapy in the perioperative phase of the high risk surgical patient

Prevention of hypotension after induction of anesthesia after preoperative tune-up. A preliminary report of the Groningen tune-up study

Objective: To investigate whether the frequently occurring hypotension after induction of anesthesia can be prevented by preoperative treatment at the ICU guided by hemodynamic data obtained from a pulmonary artery (PA) catheter.Design: Prospective controlled open randomized single center studySetting: University tertiary referral hospital.Patients: Thirty-one patients undergoing major vascular- or abdominal surgery.Interventions: Patients were randomized to either the control group or the ICU group. Patients allocated for the ICU group were admitted to the ICU the day before the operation and treatment was started aimed at a CI≥4.0 l/min/m2. No special treatment was given to the control group the day before the operation. Anesthesia was induced with etomidate, rocuronium and sufentanil.Measurements and main results: Seventeen patients were allocated for the control group and 14 for the ICU-group. Mean ages were 65±2.5 and 66±2.5 years, respectively. Both groups were comparable regarding age, sex, blood pressure and type of operation. Filling pressures at admission on the ICU were: central venous pressure 3±2 mm Hg and pulmonary capillary wedge pressure 8±3 mm Hg while CI was 3.2±0.8 l/min/m2. The hemodynamic goal was achieved in all 14 patients of the ICU-group preoperatively with a background infusion of three l/24 h crystalloids, after a mean infusion of 1623±552 ml colloids, and in seven patients a median dose of 3 μg/kg/min (range 2-6) dopamine. Blood pressure before induction was comparable in both groups. The fall in systolic BP 10 min after induction of anesthesia was 22±18 in the ICU-group versus 41±17 mm Hg in the control group (p=0.004). The fall in diastolic BP was 11±6 mm Hg in the ICU group versus 25±11 mm Hg in the control group (p=0.0003). No differences between the groups in changes of heart rate were observed: a decrease of 13±7 bpm (95% confidence intervals 8.5 to 17.0) in the ICU group versus 15±14 (95% confidence intervals 7.6 to 21.9) bpm in the control group (p=0.6).Conclusions: Hypotension after induction of anesthesia is significantly attenuated by preoperative treatment aiming at a CI≥4.0 l/min/m2 in high risk patients planned for major vascular- or abdominal surgery. (See Editorial p. 213) Copyright (C) 1999 Elsevier Science B.V