Page 828 - TNFlipTest

NS30 Neurosurgery
Blood vessels
Epineurium Perineurium
Endoneurium
Fascicle
Myelin sheath
Axon Schwann cell
SPECIALTY TOPICS Toronto Notes 2019 • nerveentrapment–nervecompressedbynearbyanatomicstructures,oftensecondarytolocalized,
Etiology
• ischemia
repetitive mechanical trauma with additional vascular injury to nerve
Investigations
• clinicalexam:power,sensation,reflexes,localizationviaTinel’ssign(paresthesiaselicitedbytapping along the course of a nerve)
• electrophysiologicalstudies:EMG/nerveconductionstudy(assessnerveintegrityandmonitoring recovery after 2-3 wk post-injury)
• labs:bloodwork(e.g.CBC,TSH,VitaminB12),CSF
• imaging:C-spine,chest/bonex-rays,myelogram,CT,magneticresonanceneurography,angiogramif
vascular damage is suspected
Treatment
• earlyneurosurgicalconsultationifinjuryissuspected
Table 19. Treatment by Injury Type
Injury Entrapment
Stretch/contusion Axonotmesis
Neurotmesis
Complications
Treatment
Conservative: prevent repeated stress/injury, physiotherapy, NSAIDs, local anesthesia/steroid injection Surgical: nerve decompression ± transposition for progressive deficits, muscle weakness/atrophy, failure of medical management
Follow-up clinically for recovery; exploration if no recovery in 3 mo
If no evidence of recovery, resect damaged segment
Prompt physical therapy and rehabilitation to increase muscle function, maintain joint ROM, maximize return of useful function
Recovery usually incomplete
Surgical repair of nerve sheath unless known to be intact (suture nerve sheaths directly if ends approximate or nerve graft [usually sural nerve])
Clean laceration: early exploration and repair
Contamination or associated injuries: tag initially with nonabsorbable suture, reapproach within 10 d
Schwann cell nucleus
Figure 26. Peripheral nerve structure
• neuropathicpain:withneuromaformation
• complexregionalpainsyndrome:withsympatheticnervoussysteminvolvement
SPECIALTY TOPICS Neurotrauma
Trauma Management (see Emergency Medicine, ER7) Indications for Intubation in Trauma
1. depressed LOC (patient cannot protect airway): usually GCS ≤8 2. need for hyperventilation
3. severe maxillofacial trauma: patency of airway is doubtful
4. need for pharmacologic paralysis for evaluation or management
■ if basal skull fracture suspected, avoid nasotracheal intubation as may inadvertently enter brain ■ note: intubation prevents patient’s ability to verbalize for determining GCS
Trauma Assessment
Initial Management
ABCs of Trauma Management
• seeEmergencyMedicine,ER2
NEUROLOGICAL ASSESSMENT
Mini-History
• periodofLOC,post-traumaticamnesia,lossofbowel/bladdercontrol,lossofsensation,weakness,type of injury/accident
Glasgow Coma Scale
EyeResponse VerbalResponse
MotorResponse
6obeyscommands 5localizestopain
4withdraws from pain
3 flexion to pain (decorticate posturing)
2 extension to pain (decerebrate posturing)
1 no response
4spontaneous
3openseyesto voice
2openseyes to pain
1 no eye opening
5oriented 4confused
3inappropriatewords
2 incomprehensible sounds
1 no response T intubated
Best response for each component recorded individually (e.g. E3V3M5)
≥13 is mild injury; 9-12 is moderate injury; ≤8 is severe injury
© Andreea Margineanu 2012