Effect of Goal-directed Crystalloid Versus Colloid Administration on Major Postoperative Morbidity

Effect of Goal-directed Crystalloid Versus Colloid Administration on Major Postoperative Morbidity

A trial in which patients having open abdominal surgery are randomized to receive either crystalloids or colloids intraoperatively, guided by esophageal Doppler. The investigators test the primary hypothesis that goal-directed colloid administration during elective abdominal surgery decreases a composite of postoperative complications within 30 days of surgery.

Patients will be given 5-7 ml/kg of crystalloid (lactated Ringer's) in the immediate preoperative period, which will be followed by 4 ml/kg/h crystalloid for maintenance normalized to ideal body weight [Men: Ideal Body Weight (in kilograms) = 52 kg + 1.9 kg for every 2.5 cm over 150 cm; Women: Ideal Body Weight (in kilograms) = 49 kg + 1.7 kg for every 2.5 cm over 150 cm].

They will then be randomly assigned to additional volume replacement, guided by esophageal Doppler, to either lactated Ringer's solution of Voluven starch.

Inclusion Criteria:

• ASA Physical Status 1-3
• Body Mass Index < 35
• Moderate risk elective abdominal surgical procedures scheduled to take ≥ two hours done under general anesthesia.

Exclusion Criteria:

• cardiac insufficiency (EF<35%)
• coronary disease with angina (NYHA IV)
• severe chronic obstructive pulmonary disease
• coagulopathies
• symptoms of infection or sepsis
• renal insufficiency (creatinine clearance <30ml/min or renal replacement therapy)
• ASA Physical Status > 3.