Fluid replacement in craniofacial pediatric surgery: normal saline or ringer's lactate?

INTRODUCTION: Pediatric craniofacial surgery requires large amounts of intravenous fluid replacement that may alter the ionic composition of body compartments. Normal (0.9%) saline (NS) and Ringer's lactate (RL) solutions are commonly used, with different advantages and disadvantages. Our hypothesis was that there would be more acidosis with NS but with no advantage of NS over RL regarding the incidence of hyponatremia. Our objective was to determine whether acid-base and electrolyte outcomes could guide fluid management in this group of patients.

METHODS: A retrospective study of 122 children younger than 5 years who underwent craniofacial surgery was performed: 63 received only NS (NS group) and 59 received RL (RL group). Blood gases, plasma sodium, and potassium concentrations were analyzed during 2 different periods: 1 to 2 hours from anesthetic induction (P-1) and 2 to 4 hours from anesthetic induction (P-2). Statistical comparisons were made with χ test and t-test, as appropriate.

RESULTS: Acidosis was more frequent in NS group than in RL patients during P-1 and P-2: 66% and 80% in the NS group versus 26% and 37% in the RL group. Severe acidosis (pH ≤ 7.25) was also more frequently in those receiving NS (39%) than RL (8%); and so was a base excess of -5 or less: NS = 53% and RL = 16%. The incidence of hyponatremia (Na < 135 mmol/L) was similar in both groups: 40% (NS) and 26% (RL) during P-1 and 52% (NS) and 50% (RL) during P-2.

CONCLUSIONS: In young children undergoing craniofacial surgery, RL may be a preferred crystalloid over NS because metabolic acidosis is less frequent, with no increased incidence of hyponatremia.