Hypothesis: “A restrictive fluid regimen in adults undergoing major abdominal surgery would lead to a lower rate of complications and a higher rate of disability-free survival than a liberal (traditional) fluid regimen”
Methods: Approximately 3000 patients undergoing elective extensive (>2h) abdominal surgery were randomized to a restrictive fluid resuscitation strategy (goal zero fluid balance) vs. traditional practice. Restrictive was described as <5ml/kg at induction, 5 mg/kg/h intraop, 0.8 ml/kg/hr for 24 hours postop and general strategy of vasopressors before volume. For the traditional practice, patients received 10 ml/kg at induction, 8 ml/kg/hr intraop, 1.5 ml/kg/hr for 24 hours postop with a general strategy of volume before pressors. Both groups were treated with albumin/blood to replace blood loss. The primary outcome was disability-free survival at one year measured via WHO Disability Assessment Schedule (WHODAS); secondary outcomes included AKI, 30-day composite mortality/surgical complications, ICU and hospital lengths of stay.
Results: No significant difference in disability-free survival at one year. Significant increase in incidence of AKI in the restrictive fluid resuscitation group. Trend toward an increase in surgical site infection in restrictive fluid group which was not significant after adjustment.
Strengths: Multicenter, international RCT; large study population with clear protocol; minimal attrition;, evaluated as modified intention to treat
Weaknesses: Variation in colloid administration per site; minimal difference in fluid administered per group (3.7L vs 6.1L); threshold of disability may be arbitrary (WHODAS score of >24 pts is associated with “25% disability”).
Key Point: Restrictive fluid resuscitation is not associated with a higher rate of disability-free survival.