Page 214 - Cote clinical veterinary advisor dogs and cats 4th

Atonic or Hypotonic Urinary Bladder 89

• Surgical stabilization: various implants used Possible Complications supportive bandage until surgical repair is
to achieve AA joint immobility Surgical: • Minimalist bandaging (see above) is usually
performed.
VetBooks.ir fixation. Advantages: immediate relief • Implant infection or failure effective, better tolerated, and associated with Diseases and Disorders
• Iatrogenic spinal cord/brainstem injury
○ Ventral techniques provide superior
causing paralysis or death
far fewer complications than large, heavy
of pain, definitive and long-term resolu-
tion of instability through promotion
complications
of AA joint arthrodesis. Disadvantages: • Vertebral fracture and associated splints and orthotics due to the small size of
most AAI patients. It also allows the client
more technically demanding, high-risk Nonsurgical: to check the bandage daily and keep it clean
complications. • Persistent instability and pain and dry.
○ Dorsal repair techniques immobilize the • Recurrent neurologic signs
joint variably. The primary advantage is • Complications of chronic supportive Technician Tips
less demanding surgical technique(s). bandaging • Dogs with AAI require constant, gentle
However, there is a higher rate of repair attention when handling to avoid acute
failure and recurrence of disease. PROGNOSIS & OUTCOME cervical flexion.
Nonsurgical management: • Take special care during intubation and
• Indications Surgical: manipulation under sedation/anesthesia to
○ Toy breed puppies (<1 year) with good • Good to excellent prognosis if preoperative avoid flexion of the neck. It is best to keep
motor function whose bones are too small motor function is good and surgical repair the neck bandaged in mild extension until
or too soft to hold implants well; recom- results in good AA joint reduction and ready to position for surgery. Once under
mend surgical repair in these patients at eventual arthrodesis anesthesia, gently taping the patient to a
skeletal maturity, sooner if ambulation is • Guarded prognosis if minimal preoperative backboard, with neck in extension is recom-
not regained within a few weeks motor function and/or respiratory compro- mended in clinical settings where the patient
○ Client is unable or unwilling to pursue mise is present is transported by gurney or undergoing
surgical repair. Nonsurgical: advanced imaging procedures.
• Recommendations • Fair prognosis if • Meticulous bandage care required
○ Soft, padded bandage (as above) with cage ○ Dog < 8 months
confinement for 4-8 weeks ○ Mild to moderate subluxation/instability Client Education
○ Pain medication as needed ○ Acute onset with no prior occurrence • Most dogs develop clinical signs of AAI after
○ No neck leads; use harness only ○ Neurologic signs are mild to moderate minor trauma from routine activities (e.g.,
○ Change of lifestyle to avoid risky activities ○ Rapid resolution of signs with treatment jumping off the sofa, playing with other
(see below) • Poor prognosis if dogs) or traumatic events.
○ Marked subluxation/instability • Nonsurgical treatment must be accompanied
Behavior/Exercise ○ Chronic or recurrent neurologic signs by change in lifestyle to avoid activities
Surgically treated patients: ○ Severe neurologic deficits (respiratory predisposing to neck trauma; no neck leads
• Avoid sudden or extreme neck flexion, compromise, marked tetraparesis) should be used (indefinitely).
neck leads, play with other dogs, and • Ventral surgical repair effects the best long-
similar activities for 6 weeks postopera- PEARLS & CONSIDERATIONS term outcome.
tively, and then gradually resume normal
activity. Comments SUGGESTED READING
Nonsurgical approach: • Surgical repair of AAI using a ventral Slanina MC: Atlantoaxial instability. Vet Clin Small
• Avoid behaviors promoting acute neck flexion technique is the treatment of choice in all Anim 46:265-275, 2016.
(e.g., jumping off bed, play with other dogs, dogs except young puppies ≤ 1 kg. Nonsurgi- AUTHOR: Beverly K. Sturges, DVM, MS, MAS,
tug-of-war). cal treatment is used in these patients until DACVIM
• May benefit from intermittent use of sup- the dog becomes skeletally mature and surgi- EDITOR: Karen R. Muñana, DVM, MS, DACVIM
portive bandage prn cal repair is feasible. Maintain them in a (Neurology)

Atonic or Hypotonic Urinary Bladder

BASIC INFORMATION
RISK FACTORS Clinical Presentation
Definition Spinal cord injury/disease, peripheral nervous DISEASE FORMS/SUBTYPES
Absent or incomplete detrusor muscle (bladder system disorders (including dysautonomia), • Detrusor atony/hypotonia with sphincter
wall) contraction urine retention, pelvic injuries atonia/hypotonia (LMN bladder)
Synonyms GEOGRAPHY AND SEASONALITY • Detrusor atony/hypotonia with normal or
hypertonic sphincter tone
Bladder atony, bladder overdistention, lower Dysautonomia ○ Neurogenic: upper motor neuron (UMN)
motor neuron (LMN) bladder bladder
ASSOCIATED DISORDERS
Epidemiology • Cystitis, bacterial (p. 232) ○ Non-neurogenic: as a result of bladder
SPECIES, AGE, SEX • Incontinence, urinary (p. 538) overdistention from any cause
Dog or cat, any age, either sex

www.ExpertConsult.com