Lecture 21: Equine neonatology II- cardiac, respiratory and GI disease of foals Flashcards
What does the ductus arteriosus normally do/connect in utero
DA connects PA to aorta- shunts blood away from lungs
what type of murmur with PDA
Continuous machinery murmur then fades to a systolic murmur
what is a VSD
communication between L and R ventricles
what type of murmur heard with VSD
loud, systolic murmur with PMI over tricuspid valve
what is included in tetralogy of Fallot
- Overriding aorta
- VSD
- Pulmonic stenosis
- RV hypertrophy
how is inflation of lung different in foal
- Decreased pulmonary resistance
- Decreased pressure in PA, RV, and RA
how does rupture of umbilical vessels affect pressure and resistance in foal
Loss if low resistance placental circulation
1. Increase systemic vascular resistance
2. Increased pressure in aorta, LV, LA
Once born __pressure becomes greater than __ pressure
aortic, pulmonary artery
what causes normal closure of ductus arteriosus
LA pressure becomes greater than RA, blood flow reversal in foramen ovale and DA, flap valve occludes FO and constricts smooth muscle to stop flow and fibrosis of DA
Foals can get respiratory disease via __ or __
in utero via placentitis or post partum
what are the most common causes of bacterial pneumonia in foals
- E. Coli
- K. Pneumonia
- Pasturella
- Actinobacillus
- Streptococcus
how do you dx bacterial pneumonia in foals
- Blood culture
- TTW- traumatic
- Rads
- Ultrasound
what is tx for bacterial pneumonia in foals
- Oxygen
- Abx- penicillins, cephalosporins, aminoglycosides
- Anti-inflammatories
- Nebulization
what are some causes of aspiration pneumonia in foals
- Meconium
- Milk
what are some causes of viral pneumonia in foals
- EHV1/4
- Influenza
what is major sequela of viral pneumonia in foals
ARDS
how can immature lungs cause respiratory disease in foals
- Surfactant- not produced get alveolar collapse
- Poor ventilation
what does R. Equi cause in foals
chronic, suppurative bronchopneumonia, abscesses
from foal- what likely cause
R. Equi
what are some extra pulmonary signs of R. Equi in foals
- Polysynovitis
- Uveitis
- Ulcerative colitis
- Septic arthritis
- Osteomyelitis
what is pathophysiology of R. Equi
- Found in soil
- Infection via inhalation
- VapA gene virulence factor allows it to live in macrophages
how do you dx R. Equi in foals
rads, ultrasound, TTW/culture
what is tx for R. Equi
Macrolide + rifampin (Erythromycin, clarithromycin, azithromycin)
what type of pneumonia does ARDS cause
acute bronchointerstitial pneumonia
what is pathophysiology of ARDS
- Acute systemic inflammatory response
- Increased epithelial permeability
- Protein rich fluid enters alveoli
- Loss of gas exchange
- Acute respiratory failure
what are some clinical signs of ARDS
- Sudden onset severe tachypnea
- Labored breathing
- Reduce bronchovesivular sounds
- Fever
- Cyanosis
- Hypoxemia
- Poor response to nasal O2
- Hyper apnea
- Respiratory acidosis
what is tx for ARDS
- Abx
- Anti-inflammatories (NSAIDS, corticosteroids)
- Nasal O2
- Air conditioned stalls/fans
- Bronchodilators
what is prognosis for ARDS
guarded
why do newborn foals sometimes have occasional crackles, especially after rising
simple atelectasis
t or f: cough reflex decreased in foals
true
what is meconium
1st fetal waste
when in meconium typically passed
first 24h-49ers
what is the most common cause of colic in neonates
meconium impactation
what is tx for meconium impaction
- Enema
- Acetylcysteine retention enema
necrotizing enterocolitis is a sequela to __
perinatal hypoxia
what is pathogenesis of necrotizing enterocolitis
- Perinatal hypoxia
- Hypoxia disrupts normal MM
- Bacteria enter bowel wall
- Bowel may rupture
what is prognosis for necrotizing enterocolitis
poor
what are some causes of foal diarrhea
- C. Diff
- C. Perfringes
- Salmonella
- Rotavirus
what does rotavirus cause/damage
damages intestinal villi—> malabsorption/ Maldigestion
what is morbidity and morality for rotavirus in foals
high morbidity , low mortality
how do you prevent rotavirus in foals
vaccinate mare during gestation
doudenal ulceration may lead to __
duodenal stricture
what is cause of tyzzers disease
C. Piliforme
what does tyzzers disease cause and signs
acute hepatitis
Signs: depression, fever, icterus, seizures, death
foal liver- what likely cause- when arrived at farm was icteric and having seizures
tyzzers diseases- C. Piliforme
what are some lab findings with tyzzers diseases
- Increased liver enzymes
- Profound hypoglycemia
what is tx for tyzzers
- Broad spectrum abx
- Nutritional support
- Supportive care
what is gastric pH of newborns and older foals
newborns: 4.1
Older foals: 2.6
stomach of nursing foals empties more __
slowly
cecum is likely functioning in foals by __wks
2
