Exam 3 Flashcards
Lecture 1
Surgery of the Equine Urinary Tract
Understand the Options for Surgical correction of cystic calculi in the horse
C/S
Hematuria after exercise
-Stranguria in males
-Posturing to urinate without passing urine, can be a sign of colic too
Dx
-Rectal palpation: can feel stones just inside the rectum, will miss a stone if your hand is too far inside
+/- Endoscopy
-Ultrasound the kidneys before treatment
-If nephritis are present highly likelihood of recurrence
Tx
-Surgical removal is recommended
Cystotomy
Perineal urethrotomy if urolith is blocking the urethra
-Mares remove manually? 5.5-6 size globe hand
-Lithoripsy (breaking up the stones)
Cystotomy
-Fasting 24-48 hrs
-Caudal ventral midline approach. Avoid caudal epigastric and external pudendal vessels BIG vessels! Move prepuce to the side to get to midline
-Parainguinal approach: preferred
-Important to do stay sutures
-Do not let go of bladder in wants to go in deep in the abdomen
-Bladder will sit in the pelvic inlet: gentle traction to exteriorize. Saline to distend if desired and let it out right before bringing the stone out, makes it easier to exteriorize
-Peel the mucosa off the stone, tightly adhered to spicules
-Lavage bladder: any pieces left can cause new stone formation
-Suture in two layers: Cushing or Lambert Do not penetrate the bladder mucosa
-Stay sutures in the bladder while suturing
Urolithiasis - Smaller stones
C/S
-Posturing to urinate with no urine
-Obstruction of urethra
Dx
-Distended bladder on rectal exam
-Endoscopy
-Palpation
Understand the when and how to perform a perineal urethrotomy
Indications
-Removal of small stones from bladder
-Allows a urination path when urethra is blocked or bladder is atonic (neurologic cause)
-Manual or lithotripsy if lucky for removal
-Procedure can be temporary or permanent
Procedure
-Perform standing under sedation
-Epidural or local infiltration
-Evacuate rectum to avoid contamination
-If possible, pass a urinary catheter into bladder
-6-8 cm incision in perineum, 4-6 cm below the anus to below ischial arch
-Heal by second intention typically, 2-3 weeks, hemorrhage with urination for 2 weeks (cut CSP)
Permanent PU
-Indications: Sabulous urolithiasis
-Suture the urethral mucosa to the skin
Removal of stones
-Endoscopic: pass endoscope through PU into bladder, use basket to remove stones
-Lithotripsy: laser through endoscope
-Lithotrite: manually break up the stone, lavage, high chance for recurrence
Understand the common signalment, diagnosis, electrolyte correction, surgical correction, and prognosis for ruptured bladder
Uroperitoneum - Foals
-Bladder rupture is most common cause
-During parturition
-Can be seen with patent urachus also
-Adults very rare but can happen
Signalment
-Foals
-During/After parturition
-Colts more common
Diagnosis
Hyperkalemia
Hyponatremia
Hypochloremia
-Peritoneal serum: creatine ratio >2
-Free abdominal fluid on ultrasound
+/- Contrast radiographs
Electrolyte Correction
Correction of hyperkalemia
-K+ > 5.5mEq/L = cardiac arrhythmias = Death
- Calcium supplementation: stabilizes action potential in the heart
- Saline fluids (no K+, LRS have K+)
- Dextrose supplementation: increases insulin = drive K+ back into cells
Draining the abdomen
-Insert catheter or small chest tube into abdomen
-Make an incision in the skin and then move skin over 2 cm before entering the abdomen: helps prevent mental herniation when tube is pulled
ECG Findings
-Peaked T waves
-Loss of P wave
-Wide QRS complex
Surgical Correction - Treatment of choice
-AFTER stabilization of foal
-Most common 2-5 cm dorsal tear
-Good prognosis if healthy
Umbilical arteries become the round ligaments of the bladder foal development
Conservative management
-May work for small tears: budget cases only
-Leave foley catheter in the bladder to keep it empty
-Can lead to infection in immunocompromised
Understand the diagnosis and treatment of a patent urachus in a foal
Urachus: is the conduit for fetal urine to travel from the bladder to the allantoic cavity
Should close at birth
-Incomplete closure is common in foals
C/S
-Moist umbilicus
-Urine will drip (or stream) during urination
Causes
-Congenital malformation
-Acquired: seen within hours to days after birth. Sepsis of the umbilicus
-Septicemia in the foal leading to local sepsis in the umbilicus
-Septic joint, other severe illness
Treatment
-Conservative
-Chemical cauterization: Silver nitrate stick, 7% iodine dip 4x per day. Contraindicated with sepsis, can lead to ruptured urachus and uroperitoneum
-Surgical resection
-Antibiotics: stand alone treatment or combined
Know how and when to repair umbilical hernias in foals
Umbilical Remnant Infection
“Ophalophlebitis”
C/S
-Heat
-Swelling
-Pain
-Ventral edema
-Purulent discharge
-Fever
Dx
-Ultrasound
-Published normals, look for structure enlargement
Tx
-Medical
-Surgical: severe or non-responsive
Surgical Correction of Patent Urachus & Umbilical Infection/Hernia
-Resect the tip of the bladder and the enlarged umbilical vessels back to “normal” tissue
Can turn into major abdominal surgery
-May be focal to umbilicus
-May extend all the way toward the liver or adjacent bladder
Umbilical Hernias
Anatomy
-Ring
-Sac
-Contents
Reducible vs non reducible
-Reducible: uncomplicated, no bowel trapped
-Non reducible: bowel entrapped, rare.
-Colic
-Do not perform FNA
-Ultrasound helps differentiate from infection
-Very common congenital abnormality, may be hereditary
-Can spontaneously close within the first few days of life
-Usually more of a cosmetic defect: occasionally bowel incarceration
Dx
-Ultrasound
-Digital palpation
Treatment
Reducible
-If <5cm usually spontaneously close, surgery if not by 4 mts
->10 cm recommend surgery, higher risk for strangulation
-Surgery is elective, unless bowel incarcerated = Emergency
Hernia clamp NOT recommended anymore
Surgery
Approach
-Dorsal recumbency: general anesthesia. Drape big area
-Elliptical or fusiform incision: trace with back of scalpel first
-Be conservative with the skin!! closure easier
-Full thickness incision to SQ
-Metzenbaums to dissect the skin from SQ: curve of the scissors toward the skin. Reduces risk of entering hernial sac, communicate with peritoneal cavity
Small Hernias
-Closed technique: do not open sac
-Carefully dissect away skin from sac
Larger Hernias >8cm
-Open technique, remove sac
-Ensures correct placement of body wall sutures
Be sure to clamp bleeders
Body wall closure
-Simple interrupted 0, 1 monofilament or braided, PDS, Vicryl
-8-10 mm apart spaced sutures
-Needle should not fully enter abdomen, but close. If not sure convert to open and check
-Use surgeon’s throw for 1st throw
-Can use towel clamps to help decrease tension on repair while closing
-SQ 2-0 monofilament, no bury knots needed
-Skin 2-0 monofilament absorbable. Intradermal ok or simple continuous pattern
-No skin staples, hard to get out
-Cover with Ioban sticky drape or stent for recovery
-Elasticon best in foals around abdomen. CM hernia belt best for adults.
Lecture Equine Urinary Tract
Uroperitoneum (raptured bladder)
Causes
-Urinary bladder ruptured: trauma during parturition colts»fillies
-Urachal tear
-Prolonged recumbency
-“Dummy” foal bladder possible, always check
-Secondary to cystitis septicemic foals
-Rapture of urachus due to umbilical abscess
C/S
-1-3 days after birth
-Depression, gradual anorexia, tachycardia
-Abdominal distention (percussion wave, rapid shallow breathing)
+/- mild abdominal pain
Straining to urinate, dribbling
-Intestinal ileus
-Dehydration
Dx
-Hx, C/S
-Hyperkalemaia
-Hypochloremia
-Hyponatreamia
-BUN, Creatinine: normal or increased
-BG: normal or metabolic acidosis
-Ultrasound: hypo echoic free abdominal fluid, bladder appearance variable, check umbilical remnants
-Peritoneum fluid analysis: Pale, yellow, copious.
**Cr peritoneal fluid/serum >2
-ECG: predisposed to bradycardia, arrhythmias (block)
-Contrast bladder radiography
Tx
-Controlled abdominal drainage (Teat cannula or 16F tube)
-Correct hyperkalemia: 0.9% NaCl, 5-10% dextrose, and Calcium brorogluconate
-Replace 100-200 ml in 1 L NaCl with 50% dextrose
-Sodium bicarbonate if acidosis, insulin/dextrose
-Check K+ every hours until <5.5 mEq/L
-Surgery after stabilized, not an emergency
-Good prognosis
Urinary Tract infection
Primary: rare
Secondary: common
Mares»Stallions
-Usually ascending infection due to defect, obstruction, catheter, paralysis
-Urethritis, cystitis, pyelonephritis
-Pathogens: same as enteric usually
C/S
-Male: urethritis, hemospermia
-Cystitis: pollakiuria, stranguria, hematuria, pyuria (pus in urine). Scalding, crystals
-Pyelonephritis: may go undetected, nephrolithiasis, CKD. Hematuria, pyuria, pyrexia, weight loss, anorexia, depression
Dx
-Urethritis in male
-Cystitis: rectal exam, ultrasound, endoscopy, urine analysis (>10 WBC/HPF, bacteria)
-Quatitive urine culture (>10,000 CFU/ml)
-Pyelonephritis: same
Tx
-Correct primary cause
-Antimicrobials: TMS, Tetracycline, Ceftiiofur, Ampicillin, Pen/Gen
-NSAIDs
Phenazopyridine relieves burning, turns urine orange,
-Pasture access, supplementation with 50-75 g of loose salt, warm water
Urolithiasis
What three things are a must for rectal palpation? S, E, B
Etiology
-Male > female
-Often more than one stone
-Bladder > urethra > kidney or ureter
-Organic matrix + inorganic material
Risk factors
-Alkaline pH
-High mineral content diet, Alfalfa
-Diet: high mineral content
-Urinary stasis
-Decreased water intake
-Bacterial infection
Most are calcium carbonate
Type 1
-Most common
-Spiculated
-Easier to break down
-Yellow, green
C/S
-Hematuria after exercise
-Incontinence
-Colic
-Frequent painful urination
Tenesmus (inclination to evacuate), tail swishing, stamping hind feet, dribbling
Dx
-Ultrasound the entire tract
-Hx, C/S, CBC, Chem
-Rectal palpation when bladder is empty
-Very close to the rectal inlet, in front of pelvic rim. Sedation, epidural, buscopan
-Endoscopy
-Pass urinary catheter
-Urine analysis and quantitative culture
Tx
-Conservative: transurethral. Mare removal by hand if small hand.
-Fragmentation by laser Lithotripsy via endoscope
-Surgery: Cystotomy, perineal urthrotomy or urethrostomy, urethral sphincterectomy
-Culture and urolith analysis
-Post-op: +7-10 days of postoperative antibiotic treatment, catheter, NSAIDs
Prevention
-Balanced mineral consumption
-Change from legume to grass hay
Urine acidification: Amnion Chloride, Amnion sulfate, Absorbic acid
-Increase water consumption
-41% recurrence
Sabulous urolithiasis
-Large quantities of crystalloid sediment
-Bladder floor accumulation, impede flow for emptying,
-Incontinence
-Neurologic and non-neurologic
C/S
-Urinary incontinence with scalding
-Gigantic bladder on palpation
Dx
-Neurologic exam
-Rectal exam
-Endoscopy
Tx
-Repeated bladder lavage
-Encourage bladder emptying
-Broad spectrum antimicrobials
-Others: bethanecol, phenazopyridine
Prognosis: poor for resolution
Discolored urine
-Hematuria
-Hemoglobin
-Myoglobin
-Drugs, pigments
Hematuria
Etiology
-A variety of diseases
-Urinary tract infection
-Neoplasia
-Urolithiasis
-Idiopathic cystitis
Location: kidney, ureter, bladder, urethra, reproductive tract
Time and duration important
Dx
-Note the timing to localize the site
-Throughout urination: kidney, ureters, bladders
-Beginning: distal urethra
-Rectal palpation
-Analysis of blood and urine
-Endoscopy
-Ultrasound
Urethral Tears
Etiology
-High pressure in corpus spongiosum
-Proximal urethra: level of ischial arch
-Often heal into fistula and are difficult to diagnose
Dx
-History, C/S
-Hematuria end of urination (urethral contractions)
-Does not appear painful, antimicrobials do not treat issue
-Endoscopy
Tx
-None
-Breeding rest for stallions
-Temporary subischial perineal urethrotomy (pressure relief valve)
Idiopathic Renal Hematuria
Etiology
-Syndrome of sudden onset
-Episodic hemorrhage
Arabian/part Arabia
Dx
-Exclusion
-Exdoscopy
-Ultrasound
Tx
-Supportive care
-Ammino caproic acid, formalin
-Nephrectomy (bleeding will re-occur from other kidney)
Prognosis: worsen over time, fatal bleeding possible
Urinary incontinence
Most of the time secondary to anatomic abnormalities, estrogen responsive incontinence in mares, or neurological abnormalities or deficiencies
Dx
-Hx, C/S, PE
-CBC, biochemistry
-Urinary catheter, endoscopy
-Rectal palpation
-Urine analysis, bacterial culture
-Ultrasound
-CSF, vitamin E
Lecture - Equine Kidney Diseases
Examination of the Urinary Tract
Hx, PE, Rectal exam (on empty, brim, helps to not miss a stone)
Hematology and Serum Biochemistry
Urine Analysis
Imaging Techniques
Normals
-Water intake: 15-20L (90L if hot)
-Urine output: 5-15L
-Urine: Many shades, normal with crystals, cloudy ok.
-Urine tonicity: SG: 1.025-1.050 (refractometer)
-Hyposthenuria: <1.008
-Isosthenuria: 1.008-1.014
-Hypersthenuria: >1.014
-Sediment: CaCO3 normal crystals, mucus.
-Reagent strip: Alkaline pH 7.0-9.0
-Bilirubin often false +
-Glucose: exercise, PPID, sedation
-Blood: Hb, Mb, RBC
-FE, protein, GGT/Cr
-Culture sensitivity
Hematology/Biochemistry
Uremia (75% lost)
-BUN/Cr
-CBC
-Electrolytes
-Other
Chronic Kidney Disease
Older Horses
Anomalies of Development
-Renal agenesis
-Renal dysplasia
-Polycystic kidney disease
Glomerulonephritis
-Immune mediated
-Primary glomerular disease
Chronic Kidney disease
C/S
-Non specific, often incidental finding
-Not frequent, more common in older horses
-PU/PD
-Ventral edema
-Less common: inappetence and depression, fetid breath, gingivitis, dental tartar. Oral or intestinal ulcerations, decreased performance. Hematuria, encephalopathy
Dx
-Anemia
-Hypoalbuminemia
-Azotemia, BUN/Cr >10:1
-Electrolytes: HypoNa, HypoCl, HyperK, HyperCa.
-Metabolic Acidosis
-Urine analysis (isosthenuria, protein, sediment)
-Ultrasound
-Biopsy
Tx
-Progressive disease
-Treat inciting cause
-Fluids, electrolytes, nutrients, replace protein.
-Treat hypertension if needed BENAZEPRIL
-VitB, anabolic steroids
Prognosis
-Poor if SG <1.015 [Cr] >10mg/dl
-Diet: good quality pasture, C-H, add fat, salt, Omega 3 FAs
