A NEUROLOGICAL SCORE FOR HOSPITALIZED NEONATAL FOALS

A 15‐point neurological score for foals was developed, and tested on foals (<8 days old) presenting to the Marion duPont Scott Equine Medical Center (n=75) and the Royal Veterinary College (n=11). The score consists of 2 scales, which are added together to provide the total score. The points and descriptors for the first scale are as follows: Bright, alert, nursing, follows mare (0); Depressed, nursing, follows mare (1); Depressed, nursing, wanders away from mare (2); Depressed, standing, not nursing, will not follow mare (3); Recumbent, able to maintain sternal recumbency part of the time, strong suckle reflex (4); Recumbent, unable to maintain sternal recumbency, suckle reflex (5); Recumbent, no suckle reflex, responds to finger in ear (6); Recumbent, no suckle reflex, legs extended most of the time and muscles tense (7); Comatose, muscles relaxed, no response to finger in ear (8). Foals with a physical cause of recumbency (e.g., flexural deformity) are scored on this scale as if they were standing. The second scale is as follows: No seizure activity (0); Single seizure of less than 10 seconds (3); Single seizure of more than 10 seconds or two seizures of less then 10 seconds (4); Multiple seizures (5); Status epilepticus (7). All scores were assigned at admission by a single investigator. The median admission neurological scores for hospital survivors and non‐survivors, and for blood culture positive and negative foals were compared with the Mann Whitney U‐test. The correlation of admission neurological scores and arterial lactate concentrations (measured on a NOVA Stat profile M or CCX analyzer) and mean arterial pressure (measured indirectly with a tail cuff) was tested with Spearman's rho coefficient. Analysis of these data was performed using SPSS version 12. Results for all tests were considered significant if the p value was less than 0.05. The median neurological score on admission of all 86 foals was 4, and the range was from 0 to 12. The median score of survivors (2) was less than that of non‐survivors (5) (p<0.001; n=86). There was no significant difference in median score between blood culture positive (4) and negative (3) foals (p=0.109; n=84). The neurological score was moderately correlated with admission lactate concentration (correlation coefficient 0.528, p<0.001, n=68), but only weakly correlated with mean arterial pressure (correlation coefficient −0.285, p=0.011, n=78). This neurological score is statistically associated with clinically important parameters (hospital survival, blood lactate concentration), and warrants further study, including investigation of inter‐observer variation in scoring.