Exam 5 Flashcards
Examination of the new Foal Lecture
The normal foal
Restraining the foal and PE
Neonatal diseases and disorders
Introduction
Failure of passive transfer
The Normal Foal
Normal Parameters
-Stand up within 1 hour
-Ingestion of colostrum within 2 hours
-Mare passing the placenta within 3 hours
-Suckle reflex within 2-20 minutes
-Mecomium (hard pelleted dark) passed by 24 hrs
-Urination 1st at 8-12 hrs, frequent, diluted normal
-Nursing 5-7 times per hour
RR: 60-80 bpm
HR: 30-40 bpm
Temp: 100-102 F
Restraining the foal and PE
Less is best
-Observe mare and foal
-Restrain in stall
-MMs, vulvar MMs and oral
-Check the palate
-CV system
-Evaluate Umbilicus
-Body weight at least 75 lbs and monitor growth
Routine post foaling
- Umbilical care: allow cord to sever on its own. Apply diluted disinfectant 0.5% chlorhexidine
- Examine placenta
- Perform PE
- Administer tetanus antitoxin (if mare without booster)
- Determine colostrum quality
- Enema
Risk Factors Mare and Foal
Mare
Pregnancy
-Disease, fever, stress, lameness
-Placenta: placentitis, placental separation
-Twins
Parturition
-Dystocia, C-section, induced parturition
Postpartum
-Agalactia, no colostrum (premature lactation)
Previous problems
-Dystocia, septicemic foal, foal with isoerythrolysis, twins
Foal
Pregnancy
-Intrauterine stress, twins, IUGR
Parturition
-Stress
-Mycomium staining, hypoxia
-Premature placental separation
-Unreadiness for birth, premature, dysmature
Postpartum
-Orphan
-Does not get up and drink, failure of passive transfer
Environment
-Foaling in contaminated area
-Cold and wet conditions
-Infectious disease on premises
-Disrupted foaling
Failure of Passive Transfer
Colostrum
-IgG, IgG (T), IgM, IgA
-9000mg/dl at parturition
-Negligible levels within 12 hours if mare is suckled actively by foal
-Cytokines, growth factors, hormones, enzymes, cells
Absorption
-Starts 1-2 hours after birth
-Declines rapidly
-Uptake by intestine pinocytosis
Risk for Sepsis
-Fescue toxicosis: galactic in mare
-Poor quality, poor quantity colostrum
-Foal can not get up, suckle, absorb
Dx
-ELISA SNAP test
-Complete <400 mg/dl IgG
-Partial 400-800
-No FPT >800 mg/dl
Prevention
-Early recognition is key
-Evaluate pre-suckle colostrum
-Colostrometer >1060 SG
Tx
<12 hr
-Equine colostrum 1-2 liters, several feedings over 8 hrs
-Colostrum bank
> 12 hr
-Commercial plasma (neg Aa, Qa)
-Fully vaccinated
-IgG >1200 mg/dl
FPT Tx
IV catheter, drip set with in-line blood filter
Hypoxic Ischemic Encephalopathy
Dummy Foal Syndrome
Neonatal Maladjustment Syndrome
Neurological exam - Normal
-Suckle: recognition of mare (cerebrum), lips (CNVII), jaw (CNV), tongue (CNVIII), Swallowing reflex (CN IX, X, XI)
-Eye: menace response absent first 1-2 weeks. Pupillary light reflex slower, slight venter-medial strabismus
-May show chomping of mouth, struggle in restraint, angular head and neck carriage, front base wide stance, increased limb reflexes, strong resting extensor tone.
-50% of time sleeping
Etiology - HIE
-Part of perinatal asphyxia syndrome
-Caused by a hypoxic insult (pre/intra/post-partum)
-Hypoxia, reperfusion
-Risk factors known
-“True cause” often not identified
-Fully examine all body systems!
Maternal Causes
-Decreased maternal O2 delivery: anemia, pulmonary disease, CV disease.
-Decreased uterine blood flow: hypotension, endoteoxemia, colic, hypertension, laminitis, pain, abnormal uterine contractions, Increased vascular resistance
Placental Causes
-Fescue toxicosis
-Premature placental separation
-Placental insufficiency (twins)
-Postmaturity, placentitis, placental edema = fescue toxicosis
-Decrased umbilical blood flow
-Excessive length of umbilical cord
Intra-partum causes
-Dystocia
-Premature placental separation (red bag)
-Induced parturition
-C-section: general anesthesia, poor uterine blood flow due to maternal positioning
-Decreased maternal cardiac output
-Decreased umbilical blood flow
-Prolonged stage 2 labor
Clinical Signs
-Paddling legs
Loss of suckle noticed first
-Weakness, incoordination
-Abnormal tongue position
-Abnormal vocalization
-Nystagmus, fixed dilated pupils
-Blindness, disorientation
-Depression, stupor
-“Jittery” behavior, flailing foal
-Seizures, coma
Lab Findings
-Glucose: hypoglycemia
-PCV: normal/dehydration
-TS: hypo/hyper
-IgG: FPT
-Blood gas: hypoxemia, metabolic acidosis
-Biochemistry: dehydration, electrolyte abnormalities, elevated enzymes
DDx
-HIE
-Trauma
-Meningitis
-Metabolic
-Idiopathic
-Congenital malformation
Tx
-Address most threatening problems first
-Control seizure
-Maintenance care, supportive care, monitoring
-Treat problem, Prevent further damage
Prognosis
-Good, poor if no improvement after 5 days
Madigan Foal Squeeze
Treatment for HIE
-Age <3 days
-Do not use if rib fracture, respiratory distress, shock, sepsis, prematurity
-Valium
-Phenobarbital
-Phenytoin
Magnesium Infusion
Dexamethasone, DMSO, Mannitol, Naloxone
Regional hypothermia?
Thiamine
Abscorbic acid
Alpha-tocopherol
Septicemia - After Foal did not get colostrum
C/S
-Recumbency
-Weight loss
-Lethargy
-Loss of suckle
-Lack of nursing
Fever, hypothermia, tachycardia, tachypnea
-MMs: hyperemic, petechiae of pinnae of ears
-Increased CRT
-Hyperemia of coronary band
Portals of entry
-Skin
-Umbilicus
-Digestive
-Respiratory
Secondary site of infection
-Joints: palpate to look for heat and distention
-Physes, synoviae
-Uveal tract
-Meninges
-Endocardium
-Liver, kidney, skin, muscle
Clinical Signs Sepsis
Primary
-Digestive: diarrhea, abdominal distension, bruxism, colic
-Respiratory
-Urachus
-Skin
Secondary
-Nervous
-Musculoskelatal
-Liver
-Eye
-Urinary
Laboratory findings
Hypoglycemia, TS: hypo/hyper, IgG: FPT
CBC: leukopenia, nuetropenia, left shift, toxic changes
Biochemistry: elevated enzymes, dehydration, electrolyte abnormalities,
Laboratory tests - Stall side
Dx
-History, C/S
-Sepsis score
Blood culture is the Gold Standard
-Arhtrocentesis, x-ray, ultrasound
Treatment for Sepsis
-Treat primary problem, secondary problem, MONITOR and CHECK all body systems
-Antibiotics (cause)
-Hypovolemia and hypotension
-Glycemia
-FPT
-Nutritional support
-Supportive care
Gentamycin 24 hr interval, nephrotoxic
IV Fluids
-Crystalloid: bolus 20ml/kg over 20 min (~1L)
-Estimare 20-25% BW divided between IV fluids and milk (often 1/2 of that is sick foals)
Monitor Glucose
-Glycemia: in utero, at birth. Causes; poor glycogenesis, lack of nutrient ingestion, increased metabolic demands
-Treatment: Use 5% dextrose (5%: 100 ml 50% in 900 ml LRS)
-Low rate, progressive increase
Nutritional Treatment
-Goal 20% BW (100-120 kcal/kg/d)
-Enteral feeding: milk replacer, mare’s milk.
-Feeding tube if no suckle: start at 5-10% per day fed in small volumes every 2-3 hrs. Progressive increase to 20%
-Parenteral nutrition if <10% of BW milk/d tolerated
Antiulcer medication
-Ranitidine
-Omeprazole
General Nursing Care
-Assisting person
-Keep warm and dry
-Provide tactile stimulation
-Assist stand regularly
-Sternal recumbency, repositioning
-Avoid decubital ulcers, prevent dependent lung atelectasis
-Sterile ocular lubricant
-Urine: monitor output, assess SG, glucosuria
-Maintain bond with mare
-Prevent decubital ulcers
-Oxygen support
Prognosis for HIE
-Relatively good if no complications
-Roughly 75% survival
-Generally no long term problems
Prognosis for Septicemia
-Depends on severity and damage extent
-Treat early, aggressive, long
Umbilical Problems
-Anatomy
-Clinical evaluation
-Infection
-Persistent urachus
-Hernia
Umbilical Care
-Let break on its own
-Diluted 0.5% chlorhexidine
-Daily monitoring
-Palpation, inspection
-Ultrasound, CBC, inflammatory markers
Ultrasound
<1 cm vessel diameter
Umbilical Infection
Localized
-Swelling
-Heat, pain
-Discharge
Generalized
-Fever
-Septic arthritis
-High fibrinogen
Simple Abscessation
-Limited to extra abdominal structures
-Foals > 1 week
-Dx: ultrasound, bloodwork
-Tx: medical hot pack, drainage. Surgical
Umbilical Infection
-Affecting more than 1 intra-abdominal structures
-Navel may look normal
-Urachus, arteries, veins can be infected
-Tends to spread: localized, systemic, bacteremia, septicemia
-Dx: ultrasound, bloodwork, check remote locations every 2-3 days
Umbilical infections
Medical
-Localized, small, if surgery is not an option
-Broad spectrum antimicrobials for 2-3 weeks
-Re-evaluate frequently plus follow fibrinogen. Change antimicrobials if no response
Surgical
-Larger lesion
-Changes in physical exam
-Increased fibrinogen
Persistent Urachus
-Frequent complication of sick foals
-Decubitus and reduced movement
-Sepsis possible
-Urine from umbilicus during urination
-Leak, abdominal cavity, subcutaneous tissue
Always ultrasound if wet umbilicus
Tx
-Conservative: frequent treatments, antibiotics, antiseptic/anesthetic local: phenazopyridine HCl
-Urinary catheter
-Surgical: refractory cases, systemic signs of infection
-Complications possible
Septic Arthritis
Emergency
Always palpate all accessible joints
-An inflamed joint is septic until proven otherwise
Etiology
-Hematogenous spread
-Foals < 30days
C/S
-Stiffness
-Sudden lameness
-Distension
-Heat, pain
-Systemic signs
->1 joint in 50% of foals
-Evaluate for septicemia
-Bloodwork, SNAP test, inflammation markers
-Imaging x-ray: no initial changes, repeat 1 week, 50% calcification before visible changes
Joint aspiration and culture most important
-Blood culture
Arthrocentesis
-18-20 g needle
-EDTA <800 cells/uL
-Proteins <1g/dl
-Culture
Ultrasound
-Floaties of fibrin in synovial liquid
-Synovitis
-Thickened cartilage
-Subchondral bone changes
Tx
-Emergency
-Lavage is essential
-Dilute inflammation and infection
-Repeat until WBC <30,000 cell/uL
-Local antibiotics: Gentamycin or Amikacin, Ceftiofur, Pene Gen
-Support wrap
-Assure adequate immunity
-Pain control
-Treat underlying nidus
-Other options: regional limb perfusion, arthroscopy, arthrotomy, beads
Colic
Neonate
-Mecomium impactions: 6-24 hrs post partum. Depression, stop nursing, straining, recumbency, abdominal distension. Dx: digital palpation, ultrasound (distension, ileus), radiographs contrast. Tx: enema, warm soapy water, retention enema acetylcystein. No food, mineral oil, fluids, pain medication (Diazepam, butorphanol)
-Ulcers: glandular/non-glandular. C/S: intermittent, rupture, no appetite, colic, ptyalism, eructation, colic, asymptomatic, perforative, pyloric or duodenal stricture. Dx: Diarrhea, teeth grinding, fever, colic, Fecal occult blood, imaging: gastroscopy, ultrasound, radiographs. Tx: Ranitidine combo with Omeprazole.
-Enteritis
-Hernia
2-5 days
-Ruptured bladder
-Ulcers
-Enteritis
-Atresia coli
Older foal
-Ulcers
-Enteritis
-Volvulus SI
-Intessusception
-Gastric outflow obstruction
Describe the components of equine PPE, including the role of the veterinarian in the process
Purpose of PPE
-Determine the CURRENT health status of the horse
NOT to
-Pass or fail, we can’t say a horse is perfectly sound, we can only tell what we found or did not found
-Can not predict the future soundness
-Can not determine suitability, if the horse is dangerous, it needs to be in the record
-Can not determine the horse’s price, it should be determined before PPE and maybe negotiate after
Components Use standardized form
- Detailed patient information, client information, who was present for the exam
- Pictures of the horse with markings visible and written in report
- Identification
-Microchip: left side of neck 1/2 way down
-Tattor: under lip in racehorses
-Freeze brand: under mane, on hip - Detailed history from seller
-Document if unable to talk to seller or agent
-What is the horse’s current workload
-Any known medical/lameness issues - Get through the body systems individually
-Cardiac: listen to arrhythmias, murmurs before and after exercise
-Respiratory: lungs, noise during exercise
-Neurological: document what tests were performed
-GI: passing normal manure, gut sounds
-Oral exam: age, dental abnormalities
-Reproductive: stallion, gelding, cryptorchid? BSE
-Integumentary: look for skin masses, surgical scars
-Lymphatic: enlarged LNs
-Ophthalmic: cataracts, cysts, corneal scars
Last musculoskeletal palpate limbs, back, joints, hoof testers, lameness exam, flexions
Describe how to deal with a horse that is obviously lame on pre-purchase examination
Communicate that finding with the buyer
-Some buyers will end the PPE there
-Other clients will continue and want further diagnostics: radiographs, ultrasound, becomes very difficult
Localizing lameness is the seller’s responsibility buyer should not pay for lameness exam on a horse that they don’t own
-Document what tests were declined as well
-Radiographs, ultrasound, endoscopy, nuclear scintigraphy, bloodwork, drug screen
Imaging
-Ultrasound, MRI, Nuclear Scintigraphy: interpretation can be very challenging
-Endoscopy for race horses URT
-Standard views: Front feet, hocks +/- stifles
-Expensive horses: front feet, all 4 fetlocks, hocks, stifles, back, neck
Bloodwork
-Drug screen: often take blood and hold it, up to 6 months frozen serum
-CBC/chemistry
-Coggins: Equine infectious anemia, need for traveling out of state
-PPID test in older horses?
-Make sure you take enough blood during exam so you don’t have to go back!
Advanced Equine Anesthesia Lecture
Develop an anesthesia plan for a horse having a field surgery, including premedication, induction, maintenance, and post operative care
Premedication
-Alpha-2 agonist +/- butorphanol IV
-IM premed for skittish horses
-Dose of alpha-2 agonist > when patient is going to be induced for general anesthesia compared to standing sedation
-IM alpha-2 agonist dose is doubled than IV
Induction
-Ketamine: can be used alone or with muscle relaxant (midazolam) ~ 10ml
-Midazolam or diazepam ~ 6-8 ml
-Both can be mixed and given as bolus.
-Do not titrate to effect, the horses needs it all
Maintenance
-Ketamine + xylazine
-15-20 minutes after induction give 1/3 of the previous dose of ketamine + xylazine for additional time
-Triple Drip only for 1 hour, too much muscle relaxation = rough recovery
Post op analgesia
-NSAID
-Local anesthesia
-Cryotherapy
-Hydrotherapy
-Opioids
-Confinement/exercise: castration 24 hrs confined. Hydrotherapy, 15 minutes exercise.
Continuous Rate Infusion
Duration
Romidifine»_space; detomidine»_space; dexmedetomidine»_space; xylazine
-Butorphanol + alpha-2 agonist = less CRI. Loading dose 0.02 mg/kg IV then 0.024 mg/kg CRI, analgesic + sedative no behavioral changes
-Crystalloid fluids isotonic
CRI xylazine
0.65 mg/kg/hr
500 ml fluid bag
10 drops/ml
450 kg horse
=1 drop/sec (10 drops/ml set)
= 0.8mg/ml
= 80 minutes of infusion
Develop an anesthesia plan for a horse having general anesthesia including premedication, induction, maintenance with inhalant anesthetic, and post operative analgesia
Pre-med
-Alpha-2 agonist IV unless needs IM for placement of IVC
+/- Opioid
+/- Acepromazine
Induction
-Ketamine + Benzodiazepine
Maintenance
-Isoflurane
Post op
-Small dose of alpha-2 agonist IV for transitioning, safety of personnel
-NSAID given prior to premedication
-Other analgesia (e.g., lidocaine CRI post colic operation)
Opioids
-Never give alone
-Butorphanol most commonly used
-Hydromorphone IV least likelihood of post op colic, decreased motility
-Morphine, fentanyl, have also been studied
-Buprenorphine
Recovery
-Hypotension and post-anesthetic myopathy
-Hypotension incidence decreases with use of TIVA or PIVA
MAP >70mmHg normal recovery
-Neonatal foals lower BP, MAP 40-60 mmHg
Treatment
-Lighten anesthetic depth
-Administer positive inotrope (Dobutamine to effect or epinephrine)
-Change to PIVA
Environment
-Quiet dark room
-Maintain safe position
-IPPV until spontaneous ventilation resumes
-Remove deflated ETT when patient swallows and remove mouth gag
Time for Recovery
-Varies
-If not up after 1 hours, sternal recumbency encourage
Post op Myopathy Prevention
-Padding
-Prompt treatment of hypotension
-IVF, analgesics, anti-inflammatory drugs, sedatives if needed, vasodilators. Rehab therapy if needed
Neuropathy
-Peripheral nerves: radial, femoral, peroneal, facial
-May return to normal within a few days or be permanent
-Young breed heavy horses rarely myelomalcia “dog sitting”
Prolonged Recovery
-Can something be reversed
-IVF warm, dextrose added
Hypoxemia causes
- Hypoventilation
- V/Q mismatch
- Decreased FiO2
- Right to left shunt
- Diffusion impairment
-Recurrent laryngeal neuropathy: use smaller size ETT
-Airway obstruction: placed 16-18 mm nasal tube if nasal edema. Phenylephrine
Determining oxygenation and ventilation status
-Arterial blood gas
Recurrent airway obstruction
-Tx: Albuterol, if severe V/Q mismatch increase minute ventilation
-IPPV 1:2 ratio
HYPP
-Signs: muscle fasciculations, weakness, prolapse of nictitating membrane, sweating and stressful events
-Tx: decrease stress (even fasting and diet changes can trigger an attack). Avoid drugs with potential to exacerbate HYPP (depolarizing neuromuscular blockers, K-pen, potassium sparing diuretics)
-Avoid NSIADs, ketamine, halothane, isoflurane, IVF containing potassium
-Oral acetazolaminde for 2 days prior to elective procedure
Calculate the following: epinephrine bolus, lidocaine bolus, and CRI, hypertonic saline bolus, and dobutamine CRI
See handnotes
Explain the differences in donkeys and mules compared to horses when it comes to planning an anesthetic event
-Donkeys are stoic (can endure hardship)
-Mules are difficult to handle
-Anatomically: narrower nasal passages, use smaller ETT, thicker skin over jugular furrow
-Drugs metabolized faster, use higher doses, except for Carprofen
-Donkeys have higher GGT values
-Hematocrit does not increased until >30% dehydration
-Higher blood pressure can lead to more bleeding
-Recovery is generally smooth
Higher end of dose for mules, lower for donkeys
Tetanus
C/S
-Siff, “stilted” gait
-Hyperesthesia/exaggerated menace
-Third eyelid prolapse
-Extended neck
-Arched back
-Raised tailhead
-Lock jaw
-Grimace face
-Recumbency and death due to paralysis of respiratory muscles
History
-Unknown vaccination history common
Tx
-Prognosis is grave
-Antitoxin: not consistently available. Side effects include Theiler’s disease
-Expensive
-Only binds circulating toxin, can’t help reverse signs
-Supportive care, mechanical ventilation
Prevention
-Vaccination
-Booster when treating even minor wounds
