Efecto de la infusión de lactato de sodio 0,5 molar sobre el medio interno de pacientes críticos.

To evaluate the impact of the infusion of sodium lactate 500ml upon different biochemical variables and intracranial pressure in patients admitted to the intensive care unit.A prospective experimental single cohort study was carried out.Polyvalent intensive care unit of a university hospital.Critical patients with shock and intracranial hypertension.

A 500ml sodium lactate bolus was infused in 15min. Plasma levels of sodium, potassium, magnesium, calcium, chloride, lactate, bicarbonate, PaCO₂, pH, phosphate and albumin were recorded at 3timepoints: T0 pre-infusion; T1 at 30minutes, and T2 at 60minutes post-infusion. Mean arterial pressure and intracranial pressure were measured at T0 and T2.

Forty-one patients received sodium lactate: 19 as an osmotically active agent and 22 as a volume expander. Metabolic alkalosis was observed: T0 vs. T1 (P=0.007); T1 vs. T2 (P=0.003). Sodium increased at the 3time points (T0 vs. T1, P<0.0001; T1 vs. T2, P=0.0001). In addition, sodium lactate decreased intracranial pressure (T0: 24.83±5.4 vs. T2: 15.06±5.8; P<0.001). Likewise, plasma lactate showed a biphasic effect, with a rapid decrease at T2 (P<0.0001), including in those with previous hyperlactatemia (P=0.002).The infusion of sodium lactate is associated to metabolic alkalosis, hypernatremia, reduced chloremia, and a biphasic change in plasma lactate levels. Moreover, a decrease in intracranial pressure was observed in patients with acute brain injury.