Spinal Surgery Anesthesia Flashcards
What is scoliosis?
Lateral rotation of the spine >10° with vertebral rotation.
What are the effects of thoracic spine scoliosis?
- ↓ Chest wall compliance
- Restrictive lung disease
- ↓ exercise tolerance
Get PFTs!
What EKG/cardiac findings might one suspect to find on a scoliosis patient? (Select all that apply)
a. RVH
b. RAE
c. LVH
d. Bi-atrial enlargement
a & b
RVH and RAE from trying to overcome pulmonary vascular resistance (increased R heart afterload)
The increased pulmonary vascular resistance of chronic, significant scoliosis can lead to ___ _______.
cor pulmonale
Enlarged RV due to lung disease.
What muscles would you expect to be affected from a C5 injury?
- Partial diaphragmatic paralysis
- Deltoids
- Biceps
- Brachialis
- Brachio-radialis
What are the hemodynamic consequences of injuries T5 and higher?
Physiologic Sympathectomy
- ↓BP
- ↓HR (T1-T4)
What medications would mostly not be effective in treatment of bradycardia with a T1-T4 spinal cord injury?
- atropine and glycopyrrolate generally wont work
- Need epinephrine
Autonomic Hyperreflexia is most often seen with cord transection above the ____ level.
T5/T6
What s/s are seen with autonomic hyperreflexia?
- Severe, transient HTN
- Bradycardia
- Dysrhythmias
- Cutaneous dilation and constriction
In autonomic hyperreflexia, cutaneous vasodilation is seen _____ the site of injury, whilst cutaneous vasoconstriction is seen ____ the site of injury.
above ; below
cutaneous vasoconstriction leads to severe transient HTN, bradycardia, and dysrhythmias
What is the basic pathophysiology of Autonomic Dysreflexia?
What are the most common causes of Autonomic Dysreflexia?
- Distended bladder/bowel
- Noxious stimuli (think surgical pain)
What is the treatment for Autonomic Dysreflexia?
- Removal of stimulus
- Deepen anesthetic
- Direct-acting Vasodilators
Injury to C3-C5 results in….
Diaphragmatic respiratory failure
Is respiratory function affected by injury to C5-C7?
Yes; impairment of abdominal and intercostal respiratory support
Why is there an increased risk of pulmonary infection with cervical spine injuries?
- Inability to cough/ clear secretions
- Atelectasis
What is poikilothermia?
Inability to maintain constant core temp
What is the pathophysiology of poikilothermia?
- SNS pathway disruption
- Temperature sensation disruption
- Inability to vasoconstrict below spinal cord injury
Spinal deformities are associated with _______ respiratory patterns, often necessitating PFT’s and an ABG.
Restrictive respiratory patterns
Flaccidity in which two muscles would indicated possible cervical spine fracture?
- Deltoids
- Biceps
With neurologic or spinal cord injury surgery, the anesthesia provider must make what consideration when developing an anesthetic plan regarding drug choice?
Must consider the need for SSEP/MEP/EMG monitoring
some anesthetic drugs will interfere with these monitors
What is the greatest risk with a cervical sitting position?
VAE (Venous Air Embolism)
An anterior approach for a thoracic spine procedure requires what position and equipment?
- Lateral position with bean bag
- Double Lumen ETT or bronchial blocker
May have to drop lung for access.
A posterior approach for a thoracic spine procedure requires what position and equipment?
- Prone with arms tucked or <90° abduction
- Single lumen ETT.
With prone positioning, what should be considered to prevent drooling/secretions?
anti-sialogogue preop (glycopyrrolate)
What airway considerations should be made with prone positioning?
- corrugated adapter for flexibility
- assess for BBB after turning (make sure not R main)
- Monitor for unintentional extubation
- prone to airway edema (leak test)
What are the three causes of postoperative vision loss secondary to prone positioning?
- Ischemic Optic Neuropathy (ION)
- Retinal vessel occlusion
- Cortical brain ischemia
T/F. Ischemic optic neuropathy occurrence requires direct pressure placed on the eyes?
False. Can occur without direct pressure.
*Occurs due to ↓ blood flow or O₂ delivery.
What are risk factors for ION?
- Male
- Obesity
- Wilson Frame Use
- > 6 hour surgery
- ↓ colloid usage
- Blood loss > 1000 mL
What is the typical onset of ION?
24 - 48 hours postop
What are the symptoms of ION?
Bilateral
- Painless vision loss
- Non-reactive pupils
- No light perception
What are the treatments for ION?
- Acetazolamide/diuretics
- Corticosteroids
- Hyperbaric O₂
- BP and Hgb management (transfusion, colloids, minimal permissive HoTN)
