Reasons for performing the study: Admission L-lactate concentration is a useful and commonly measured biomarker not previously prospectively
evaluated in a large multicentre study of critically ill neonatal foals.
Objectives: To evaluate overall outcome and the association of survival and L-lactate concentration at admission (ADMIT) by periparturient history,
presenting complaint and clinicians’ major diagnosis for ill neonatal foals.
Methods: Thirteen university and private equine referral hospitals enrolled 643 foals over the 2008 foaling season. Case details, historical, clinical and
clinicopathological data were entered into standardised spreadsheets then unified for analysis.
Results: Overall survival was 79% (505/643). Risk of nonsurvival increased with each 1 mmol/l increase in ADMIT (odds ratio 1.14, P<0.001). Mean arterial
pressure had a small (r2 = 19.1) but significant (P<0.001) association with ADMIT. Foals experiencing knowndystocia or premature placental separation had
increased ADMIT (P<0.001). Single umbilical problems (excluding uroperitoneum), meconium impaction only and failure of passive transfer of immunity
only had 100% survival. Six clinicians’ major diagnoses had increased odds of nonsurvival for each 1 mmol/l increase in ADMIT: ‘sepsis’; ‘unspecified
enterocolitis’; ‘unspecified colic’; ‘unspecified trauma’; ‘immune related (not failure of passive transfer of immunity)’ and ‘respiratory only’.
Conclusions and potential relevance: Survival of critically ill foals is good but varies with peripartum history, presenting complaint and clinicians’ major
diagnosis. L-lactate concentration at admission proves its utility as a valuable prognostic biomarker in neonatal foals and its utility appears to vary with
peripartum history and clinicians’ major diagnosis.