In Reply We thank Schlapbach et al for their letter and their analyses showing the comparability of the association between venous and arterial lactate and odds of mortality in children critically ill with infection.
Both their study of 4403 children with invasive infections in intensive care units in Australia and New Zealand and our study of 1299 children with clinically suspected sepsis in an emergency department in the United States demonstrated an association between early lactate levels and mortality.1,2 As 2 of the largest cohorts evaluating the question of first-hours lactate in pediatric sepsis to our knowledge, similar conclusions were reached in our study, entirely using venous lactate, and their study including both arterial and venous lactate measurements. The additional analyses included in their letter serve as important confirmation that arterial and venous lactate are similarly associated with mortality.