Is an increase in lactate concentration associated with cardiac dysfunction after the Fontan procedure?

To investigate how blood lactate concentration changes in the early postoperative course after the Fontan procedure, and whether such a change is associated with postoperative hemodynamics.

Eight pediatric patients who underwent the Fontan procedure for congenital heart disease were included. Enrollment criteria were body weight >10 kg and staged Fontan procedure following the bidirectional Glenn procedure. Blood lactate concentration and central venous oxygen saturation (SvO2) were measured at five points: before skin incision, upon intensive care unit (ICU) admission, 15 minutes before, 15 minutes after, and 2 hours after extubation. Cardiac index (CI) was continuously monitored using the pulse contour technique.

Lactate concentration increased in the ICU, peaking from 15 minutes before (2.7+/-1.3 mmol/L) to 15 minutes after (3.0+/-1.3 mmol/L) extubation. Values returned to normal parameters (1.0+/-0.1 mmol/L) within 48 hours. The CI values were also higher immediately after extubation (4.0+/-0.6 L/min/m2) than at ICU admission (3.3+/-0.6 L/min/m2) and before extubation (3.6+/-0.6 L/min/m2) (p=0.012). No significant change in central SvO2 or blood pressure (BP) was evident during the study period.

In the early postoperative period after the Fontan procedure, blood lactate concentration increased temporarily around the time of extubation but the increase was not associated with hemodynamic deterioration.