Effect of lactate versus acetate-based intravenous fluids on acid-base balance in patients undergoing free flap reconstructive surgeries

BACKGROUND AND AIMS: Use of lactated intravenous fluids during long surgeries could cause lactate accumulation and lactic acidosis. Acetate-based solutions could be advantageous as they are devoid of lactate. The primary aim of the study was to assess the effect of use of an acetated solution or Ringer's lactate (RL) as intraoperative fluid on lactate levels in patients without hepatic dysfunction undergoing prolonged surgeries. MATERIAL AND METHODS: This was a prospective, randomized, controlled trial involving sixty patients belonging to American Society of Anesthesiologists Physical Status I to II undergoing major head and neck surgeries with free flap reconstruction. Patients were randomly allocated into two equal groups, Group sterofundin (SF) and Group RL. Group SF was started on acetate-based crystalloid solution (sterofundin B Braun(®)) and Group RL received RL intravenously at the rate of 10 ml/kg/h to maintain systolic blood pressure above 90 mmHg. Blood loss >20% was replaced with packed cells. Arterial blood gas analysis was done 2(nd) hourly till 8 h. Chi-square test was used to compare categorical variables. Independent sample t-test was used to compare means. RESULTS: Intraoperative lactate levels were significantly high in RL group at 2, 4, 6, and 8 h. The pH was comparable between groups except at 8 h where RL group had a significantly lower pH than SF group (7.42 ± 0.1 vs. 7.4 ± 0.1). Sodium, potassium, chloride, bicarbonate, and pCO(2)did not show any significant difference between the groups. CONCLUSION: Use of acetate-based intravenous solutions reduced levels of lactate in comparison with RL in patients undergoing free flap reconstructive surgeries.