21. Cervical Spine injury Flashcards
What are the problems of anaesthetising a patient with a C6 transection
6 weeks after the accident?
a+b
Cervical spine
Difficult intubation − metalwork, reduced neck movement
Respiratory insufficiency
History of ICU admission
Lower RTI’s
Impaired ability to cough
Tracheostomy
Atelectasis and V/Q mismatch
Circulation
Cardiovascular problems
Autonomic hyperreflexia
Postural hypotension (may need pre-loading prior to induction)
Bradycardia (especially with intubation, pre-treat with atropine)
Venous access Cannulation can be difficult with decreased skin blood flow
Anaemia Especially with chronic sepsis
Renal
Renal impairment
Due to recurrent UTIs (catheters and vesico-ureteric reflux)
Drugs
Altered response to drugs
Suxamethonium −denervation hypersensitivity
Receptors spread from the end-plate to cover the whole muscle.
Avoid between 3 days and 9 months.
Decreased blood volume and decreased lean tissue mass
result in decreased volumes of distribution for many drugs.
Medication
Anticoagulants, , baclofen
Other
Positioning
Positioning intra-operatively
Pressure sores, contractures and spasms
Decreased gastric emptying
Risk of aspiration
Temperature
Patients can become partially poikilothermic as normal
mechanisms of thermoregulation are impaired.
Chronic pain problems
Tell me about autonomic hyperreflexia
It is characterized by a grossly disordered
autonomic response to certain stimuli below the level of the lesion.
Occurs in about 85% of patients with a lesion higher than T7.
Onset is from 3 weeks to 12 years post-injury.
Results in hypertension (may be severe with diastolic >170 mmHg),
sweating and headache.
Reflex bradycardia and skin changes
(pallor or flushing) above the level of the lesion are common.
Neurophysiologically, there is loss of descending inhibition from higher
centres and deranged alterations in connections within the distal spinal cord.
This results in inappropriate sympathetic reflexes causing profound vasoconstriction.
What are the triggers of autonomic hyperreflexia?
Pelvic visceral stimulation (especially bladder distension) is very commonly implicated.
Bowel distension (including constipation)
Uterine contractions
Urinary tract infections
Pressure sores
How is it treated?
Removal of the cause (exclude bladder distension)
Sit upright
.
Drugs need to be of rapid onset:
Sublingual nifedipine 10mg
GTN
a-adrenergic blocking agents
Hydralazine
Clonidine
Increasing depth of general anaesthesia
Use of spinal anaesthesia
Epidural anaesthesia is used to prevent autonomic hyperreflexia in
parturients
