lecture 35 Flashcards
1
Q
What are the principles of managing DMD?
A
Multidisciplinary team
- genetic counselling
- maintaining ambulation
- prevention and treatment of contractures
- anticipatory monitoring for DMD complications
- medical therapy of DMD
- pallative care
- resp. doctor
- speech pathologist
- neurologist
- physio
- occupational
- social worker
- orthopaedic surgeon → orthopaedic managent
- cardiologist
- psychosocial management
- corticosterods
- sees up to all of these people in one visit
2
Q
What is genetic counselling?
A
- commences at time of diagnosis
- a lot of guilt –> inherited
- the aim is disease prevention
- allow those who are carriers to have normal boys
- allow those who are not carriers to stop worrying
- a deletion is demonstrated in about 2/3 of patients
- there are still issues with confirming carrier status in females
- if the proband (their son) has no demonstrable deletion
- germinal mosaicism
- up to 1/3 mutations are de novo
- antenatal diagnosis is most accurate with deletions
- ? role of newborn screening for DMD
- debate
- look for common deletions?
- ethical issues
- still some difficulties
3
Q
how is ambulation maintained? why do we maintain it?
A
- as long as the child with DMD is ambulant, he can live a reasonably independent existence and cope with most daily activities
- when ambulant, there is less tendency to develop contractures and scoliosis
- once the child loses ambulation he loses much of his independence and is prone to increasing complications such as contractures and deformites
- wheelchair = big deal
- weight control, diet, exercise: want to avoid obesity
- prevent contractures
- physiotherapy
- corticosteroids
4
Q
What are joint contractures in DMD?
A
- toe-walking is common in early DMD
- achilles tendon contractures
- progressive contractures: hips, knees, elbows, wrists
- more problematic after wheelchair bound
arise because of:
- static positioning in a position of flexion
- muscle imblance around joint
- fibrotic chagnes in muscle tissue
5
Q
How do we prevent/minimise contractures?
A
- maintain ambulation
- passive stretching, physiotherapy
- active, active-assisted and passive stretching
- need to do it everyday
- night-time splints and braces
- try to make exciting e.g. space boots
- surfical release of contractures
- tendo achilles releases
- anterior hip releases
6
Q
What is the surgical approach?
A
- individual approach in all
- surgical approaches vary
- surgery for lower extremity contractures may prolong ambulation by 1-3 years
- bracing is required post-operatively
- important to mobilise boys immediately post-operatively
7
Q
How much exercise in DMD?
A
- concerns regarding contraction-induced muscle fibre injury
- sub-maximal aerobic exercise has a number of positives
- CV health
- maintenance of muscle strength and range of motion, avoidance of disuse atrophy
- weight control
- quality of life
- avoid overwork and over-exertion
- avoid eccentric/high-resistance strength training
- swimming: aerobic, uses respiratory muscles, can be continued by the non-ambulant
- kids are good at regulating own level of activity
8
Q
What is anticipatory monitoring?
A
for expected or common cpmplications of DMD
- learning problems
- scoliosis
- respiratory muscle weakness
- cardiomyopathy
9
Q
How are learning disabilites managed?
A
- early intervention strategies
- speech therapy, physiotherapy (maybe in school setting), occupational therapy
- assessment of skills and weaknesses
- formal neuropsychological assessment in school-age children
- tailored school programme
- provision of aide in classroom
- appropriate careers counselling
10
Q
What is scoliosis in DMD?
A
- boys not treated with steroids:
- -90% chance of developing scoliosis
- small chance of vertebral compression fractures from osteoporisis
- boys treated with steroids:
- less risk of scolios
- greater risk of vertebral fractures
11
Q
How do we monitor the spine in DMD?
A
- clinical observation through the ambulatory phase
- once not walking:assessed at each visit
- annual x-rays
- guidelines for surgery
- spinal curve > 25 degrees
- vital capacity ? 30% of predicted
- no active infection
- no significant cardiomyopathy
- important to only do when necessary, it is a big surgery, big operative risks, hard to recover from etc etc
12
Q
What is the cobb angle?
A
- 25ºangle of the spine
13
Q
What is spinal fusion?
A
purposes
- straightens the spine, improves seaated posture and comfort
- prevents further worsening of deformity
- eliminates pain due to vertebral fracture with osteoporisis
- slows the rate of respiratory decline
- doesn’t restore lost pulmonary function
- average afe at surgery is about 14 years
- in experienced centres mortality and morbidity are low
- spinal bracing improves posture and comfort in those unfit for surfery, but will not stop scoliosis progression
14
Q
What are potential complications?
A
complications of anesthesia
- malignant hyperthermia (at higher risk than normal population)
- respiratory problems
- cardiac arrhythmias
post-operative pain
loss of muscle conditioning
- rapid loss of strength with immoblisation
- deconditioning
loss of arm use
- decreased spinal mobility
15
Q
What are anaesthetic risks in DMD?
A
- malignant hyperthermia
- a pharmacogenetic predisposition to high fever and muscle breakdown after exposure to some anaesthetic agents
- acute hyperkalemia (cardiac arrhythmias) without kyperthermia
- profound hyperCKaemia with induction anaesthesia
need to avoid ‘triggering’ anaesthetics: halothane, succinylcholine
disease-related risks
- acute cardiac and respiratory decompensation
