VEHICULAR POLYTRAUMA IN A CAVALIER KING CHARLES

SPANIEL PUPPYAriel Kravitz

Senior Seminar March 5, 2014

Basic Science Advisor: Dr. Marnie FitzMauriceClinical Advisor: Dr. Chelsie Estey

OUR PATIENT

Signalment 13 wo FI CKCS

Not vaccinated Previously diagnosed with Bordetella

Day 2 of Amoxicillin/Clavulanic acid

1 DAY PRIOR TO PRESENTATION TO CUHA

Unsupervised outside Good Samaritan witnessed the vehicular trauma

and brought her to an ER/CC center Treated for shock and cerebral edema Kept overnight - no improvement

PRESENTATION TO CUHA EMERGENCY

Initial assessment Vocalizing in pain when moved → methadone Mild hypoxemia (SpO2: 21%: 92-93%) Hypotensive (96/58) (MAP 72) → fluid bolus T FAST → negative A FAST → negative Parvovirus SNAP test → negative

PRESENTATION TO CUHA EMERGENCY

Neurologic examination Mental Status: Bright, Alert, Responsive Attitude/Posture: Slightly hunched posture Conformation/Muscularity: Normal Gait: Non ambulatory paraparesis (with minimal motor) Cranial Nerves: Normal Proprioception: Absent in pelvic limbs Spinal Reflexes: normal thoracic limb reflexes; decreased

withdrawal reflexes bilaterally in the pelvic limbs; decreased patellar reflexes on the right and absent on left; normal cutaneous trunci reflex on the right but cutoff at L3 on the left

Nociception: lumbar discomfort

PRESENTATION TO CUHA EMERGENCY

Neurologic examination Mental Status: Bright, Alert, Responsive Attitude/Posture: Slightly hunched posture Conformation/Muscularity: Normal Gait: Non ambulatory paraparesis (with minimal motor) Cranial Nerves: Normal Proprioception: Absent in pelvic limbs Spinal Reflexes: normal thoracic limb reflexes; decreased

withdrawal reflexes bilaterally in the pelvic limbs; decreased patellar reflexes on the right but absent on left; normal cutaneous trunci reflex on the right but cutoff at L3 on the left

Nociception: lumbar discomfort

PRESENTATION TO CUHA EMERGENCY

Neurologic examination Mental Status: Bright, Alert, Responsive Attitude/Posture: Slightly hunched posture Conformation/Muscularity: Normal Gait: Non ambulatory paraparesis (with minimal motor) Cranial Nerves: Normal Proprioception: Absent in pelvic limbs Spinal Reflexes: normal thoracic limb reflexes; decreased

withdrawal reflexes bilaterally in the pelvic limbs; decreased patellar reflexes on the right but absent on left; normal cutaneous trunci reflex on the right but cutoff at L3 on the left

Nociception: lumbar discomfort

Neurolocalization: T3-L3 and L4-S3 myelopathy

PRESENTATION TO CUHA EMERGENCY

Plan Full body CT Restrained on a backboard in O2 cage Supportive care in ICU Transfer to the Neurology Service in the AM

FULL BODY CT- HEAD

Transverse soft tissue window post-contrast Coronal bone window post-contrast

FULL BODY CT- HEAD

Transverse soft tissue window post-contrast Coronal bone window post-contrast

FULL BODY CT- HEAD

Transverse soft tissue window post-contrast Coronal bone window post-contrast

FULL BODY CT- CERVICAL VERTEBRAE

Sagittal bone window

FULL BODY CT- CERVICAL VERTEBRAE

Sagittal bone window

FULL BODY CT- THORAX

Transverse soft tissue window

FULL BODY CT- THORAX

Transverse soft tissue window

FULL BODY CT- LUMBAR VERTEBRAE

Transverse bone window through L4 Sagittal bone window throughL3-L5

FULL BODY CT- LUMBAR VERTEBRAE

Transverse bone window through L4 Sagittal bone window throughL3-L5

Transverse bone window through L3

PROBLEM LIST

Comminuted fracture of L4 vertebra Fissure fracture of C3 vertebra Bilateral pulmonary contusions Fractures of the right orbit Fractures of the frontal sinus with pneumocephalus

and intracranial hemorrhage Hypoxemia Bordetella positive

VEHICULAR POLYTRAUMA

High energy blunt injury Trauma - 2nd most common cause of death Most common cause of vertebral fractures

2nd spinal fracture/luxation - ~20% Additional injuries – 40-50%

PE findings more sensitive than radiographs

Figure 2 from Evaluation of vehicular trauma in dogs: 239 cases (January-December 2001)

SPINAL TRAUMA

Pathophysiology 1o injury

Immediate result of the trauma Mechanical damage to the spinal cord → physical disruption

of neuronal and glial cell membranes 2o injury

Hours to days following trauma Biomechanical processes triggered by the primary injury →

worsening spinal cord damage

SPINAL TRAUMA

Pathophysiology 1o injury

immediate result of the trauma Mechanical damage to the spinal cord → physical disruption

of neuronal and glial cell membranes 2o injury

Hours to days following trauma Biomechanical processes triggered by the primary injury →

propagated spinal cord damage

PRIMARY SPINAL CORD INJURY

3 compartment model Boney and soft tissue structures

Dorsal Middle Ventral

If 2 of the 3 compartments are affected → unstable injury

Figure 12.1 from A Practical Guide to Canine and Feline Neurology

GOALS OF SPINAL MANAGEMENT

Prevent ongoing primary injury and allay perpetuation to secondary injury

Stabilization of a fracture is based on: The damaged structures The forces acting on them

VERTEBRAL FRACTURE REPAIR

Goals Realign and stabilize the spinal column Decompress the spinal cord

Surgical techniques Pins + PMMA* Locking plates * External fixators* Vertebral body plates Modified segmental fixation Tension band stabilization Spinous process plating

VERTEBRAL FRACTURE REPAIR

Goals Realign and stabilize the spinal column Decompress the spinal cord

Surgical techniques Pins + PMMA* Locking plates * External fixators* Vertebral body plates Modified segmental fixation Tension band stabilization Spinous process plating

L4 VERTEBRAL FRACTURE REPAIR Dorsal laminectomy

Dorsal decompression Visualize L4 vertebral fracture

Cortical screw placed transarticularly through the R articular facet joint of L4

4 screws placed bicortically through L3 and L5 Screws placed through the base of L and R transverse processes of L3 Screw placed through the base of the L transverse process of L5 Screw placed through the R transverse process and pedicle of L5

PMMA with cefazolin molded around the screws

Fig. 35-6 from Small Animal Surgery

POST-OP CT

Transverse bone window through L5

Sagittal bone window through L2-L5

POST-OP CT

POST-OP TREATMENT

Treatment 40% O2 Plasmalyte + 1.5% dextrose Fentanyl CRI Ampicillin/Sulbactam Ceftazidime Ondansetron, Pantoprazole and Sucralfate

DAY 1 POST-OP PROGRESS

Neurologic examination – Day 1 post-op Ambulatory paraparesis with voluntary motor function in

all limbs Absent placement in the hindlimbs bilaterally Intact withdrawal, patellar and perineal reflexes Cutaneous trunci reflex cutoff at the level of L3 on the

left; normal on the right Continue to improve in hospital Oxygen independent day 3 post-op Fluids tapered and switched to all oral medication

DAY 5 POST-OP

TGH Medications

Cefpodoxime Amoxicillin/Clavulanic acid Pregabalin Tramadol Metronidazole

Exercise restriction At home rehabilitation

PROGNOSIS

Fair to good Comminuted fracture - L4 Vertebra

Failure of perfect anatomical alignment - potential for the spinal cord to be compressed if the fragments dislodge from their current locations

60-70% chance to return to normal function Fissure fracture - C3 Vertebra

Not at issue at this time Potential for neurologic deficits in the future

Growing Trauma

PROGNOSIS

Bilateral pulmonary contusions – improving Fractures of the right orbit

Not at issue at this time Unknown in future

Fractures of the frontal sinus with pneumocephalus and intracranial hemorrhage Not at issue at this time Unknown in future Predisposed to seizures

RECHECK 1

4 weeks post-op Neurolocalization: Thoracolumbar spine (T3-L3)

Mild hindlimb spinal ataxia Absent postural thrust on the right, delayed on the left,

normal placing in all four limbs Pain elicited on head palpation, cranial cervical and

thoracolumbar spine Spinal radiographs

RECHECK 1- SPINAL RADIOGRAPHS

RECHECK 1

Prognosis Still fair to good

Recommendation: Medications

Pregabalin Tramadol

Exercise restriction At home rehabilitation

RECHECK 2

10 weeks post-op Neurolocalization: Thoracolumbar spine (T3-L3)

Mild hindlimb spinal ataxia Delayed hopping on the right pelvic limb, normal

hopping in other limbs, normal placing in all four limbs

No pain elicited on palpation Spinal radiographs

RECHECK 2 - SPINAL RADIOGRAPH

RECHECK 2

Prognosis Good!

Recommendation: Medications

Pregabalin (tapered dose for 1 week) Tramadol

Exercise restriction

COST IN HOSPITAL

Initial Stay

ECC exam $113.00

Full body CT $733.00

Surgery + Anesthesia $2078.26

Supportive therapy +maintenance in ICU x 9 days $4254.34

Total $7178.60

4 Week Recheck

Exam + Radiographs $220.40

10 Week Recheck Exam + Radiographs $200.00

Total Cost $7599.00

SELECTED REFERENCES Dewey, C. A Practical Guide to Canine & Feline Neurology. 2nd ed. pp 405-

414. Wiley-Blackwell, 2008. Ames, Iowa. Fleming J.M. et al. Mortality in north american dogs from 1984 to 2004: an

investigation into age-, size-, and breed-related causes of death. Journal of Veterinary Internal Medicine. 2011 Mar. 25(2), pp 187-98.

Fossum , T. Small Animal Surgery. 1st ed. pp 1118-1127. Mosby and Co., 1997. St. Louis, Missouri.

Olby, N. The pathogenesis and treatment of acute spinal cord injuries in dogs. 2010 Sep. 40(5), pp791-80.

Rockar, R.A et al. Development a Scoring System for the Veterinary Patient. Journal of Veterinary Emergency and Critical Care. 2007 Jul. 4 (2), pp 77-83.

Streeter, E. et al. Evaluation of vehicular trauma in dogs: 239 cases (January–December 2001). JAVMA. 2009 Aug. 235 (4), pp 405-408.

Tobias K, Johnston S: Veterinary Surgery: Small Animal. 1st ed. pp 487-496. Elsevier/Sauders, 2012. St. Louis, Missouri.

THANK YOU

Dr. Chelsie Estey Dr. Marnie FitzMaurice Dr. Sofia Cerda-Gonzalez My family Class of 2014

QUESTIONS?