obtunded foal

Presenting signs

·    Obtunded – decreased mentation but responsive to visual and auditory stimuli

·    Stuporus – only responsive to painful stimuli

·    Comatose – unresponsive to painful stimuli

·    Pale MM/icterus, obtunded, tachycardic, seizures – neonatal isoerythrolysis

Investigations

·    Clinical exam

o  TPR

o  MM colour – pale/icteric = neonatal isoerthrolysis

·    IgG – test for passive transfer of antibodies

o  >800mg/L = normal, <800 = failure, <400 = complete failure (increased risk of secondary infections and sepsis)

·    Glucose – hyponatraemia can cause obtunded foals and seizures, if not nursed

·    Lactate – normal neonates have mild increase but if severe increased = disease

·    USG – first urination will be higher conc. then should decrease

·    Haematology – leukopenia and neutropenia likely – low PCV/marked anaemia = neonatal isoerythrolysis

·    Biochemistry – increased creatinine due to decreased clearance

·    Inflammatory markers – increased SAA = acute inflammation, increased fibrinogen = chronic inflammation (indicates in utero infection/inflammation

·    Sepsis in foals – at least 3 of:

o  Pyrexia, tachycardia, tachyonoea, leukocytosis/leukopenia, increased blood lactate, increased blood glucose

Management

·    SEPTIC UNTIL PROVEN OTHERWISE – abx (C+S), IVFT, supportive care + REFER

o  Oral TMPS if low septic risk

o  If high risk of sepsis/already septic – check renal function

§ Normal renal function – IV ampicillin + amikacin

§ Abnormal renal function – IV ceftiofour (protected am but appropriate here)

·    Neonatal maladjustment syndrome

o  May require intensive care

o  May just require supportive care, e.g. NG tube colostrum, abx

·    Neonatal isoerythrolysis

o  Minimise stress

o  If <24h, prevent from nursing to prevent further ab ingestion, give colostrum from another mare

o  Supportive care, whole blood transfusion if deteriorating

Causes

·    Sepsis/SIRS

o  Due to enteritis, pneumonia, uroabdomen

·    Neonatal maladjustment syndrome (neonatal encephalopathy)

·    Prematurity/dysmaturity

o  Premature – born <230d

§ Signs: small, silky coat, round forehead, floppy ears, entropion, fetlock/carpal contracture, incomplete ossification of cuboidal bones

o  Dysmature – born at full term but has characteristics of premature

o  Consequences: generalised weakness, abnormal glucose metabolism, respiratory dysfunction (lack of surfactant), endocrine dysfunction (insulin sensitivity)

·    Neonatal isoerthrolysis

o  Ingestion of maternal anti-RBC antibodies ® destruction of foal RBCs

o  History of blood transfusion in mare

·    Trauma

·    Musculoskeletal issues

·    Risk factors for abnormal neonatal foal:

o  Maternal – dystocia, concurrent dam illness, prematurirty, poor bonding

o  Placental – placental insufficiency, placentitis

o  Foal – FPT, sepsis, encephalopathy, omphlalitis, congenital defects, trauma