Transcript Inborn Errors of Metabolism

Board Review 6/7/2013
What is your favorite letter?
A. C
B. D
C. E
D. A
E. B
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Assess a patient with head trauma and
determine if a significant intracranial injury (ICI)
has resulted
Recognize an increase in intracranial pressure
Initial management of acute CNS trauma
Outpatient management of minor head trauma
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Primary injury
 Mechanical damage to skull/tissue
 Shearing forces  vessel rupture  bleeds
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Secondary injury
 Ongoing derangement to neuronal
cells due to:
 Hypoxia, hypoperfusion (local or
systemic shock), metabolic
derrangements (hypoglycemia),
expanding mass, increased pressure,
edema
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ABCs first!
History
 Details of injury mechanism
 Fall: height and surface type
 MVC: Use of restraining devices, speed
 Action of victim (thrown, rolled, etc)
 Timing of symptoms
 LOC, amnesia, confusion, seizure, vomiting, headache,
general behavior
 Risk factors:
 Seizure d/o
 Adolescent: drugs/intoxication
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Physical Exam
 Mental Status!! Use the Glasgow Coma Scale
 Examine head for obvious evidence of trauma
 Severe brain injury/trauma may be present in a patient
who has NO external signs of trauma
 Neurologic exam
 Look for focal findings
 Fundoscopic exam: look for retinal hemorrhages
A patient presents with blood draining from his
ears, ecchymoses in the orbital area, and
postauricular bruising. He likely has what type of
fracture?
A. Basilar skull fracture
B. Simple linear skull fracture
C. Scapula fracture
D. Depressed parietal skull fracture
E. Femur fracture
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Basilar Skull Fracture
 Ecchymoses in the orbital area
 Blood behind the TM
 Battle sign (postauricular bruise)
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Temporal Bone Fracture
 Bleeding from the external auditory canal or
hemotympanum
 Hearing loss
 Facial paralysis
 Cerebrospinal fluid otorrhea
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Has an ICI occurred?
 Clear predictors:
 GCS ≤ 14 or altered mental status
 Focal neurologic abnormalities
 Skull fracture
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Yet many people with ICI lack these
features…when do we do imaging?
Consider children < 2 years old separately
 More difficult to assess, more easily injured from short
falls, higher incidence of asymptomatic injuries, more
often victims of inflicted injury
What type of intracranial injury is this?
A. Subdural hemorrhage
B. Subarachnoid hemorrhage
C. Epidural hemorrhage
D. Cerebral Contusion
E. Diffuse axonal injury
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Focal Hemorrhage:
 Epidural
 Lens-shaped; often has overlying fracture
 “lucid interval” common on Boards only
 Subtle signs: vomiting, headache, often asymptomatic  can progress
rapidly
 Subdural
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Crescent-shaped; can be bilateral
Associated with underlying brain injury
Present with LOC, AMS, lethargy
Suspect NAT
 Subarachnoid
 Rarely associated with mass effects
 Usually seen with other ICIs
 Present with LOC, headache, meningeal irritation
 Cerebral contusion
 Brain bruise: can have coup and contrecoup (brain striking skull)
 Present with subtle signs: vomiting, headache, LOC, ?focal neuro defect
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Diffuse Injury
 Diffuse axonal injury
 Injury to white matter due to shear forces
 Acceleration/deceleration or rotational forces (MVC)
 Present in coma or less commonly like a concussion
 CT scan with small areas of hemorrhage near gray-white
interface
 Cerebral edema
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Severe head trauma
May not be visible on initial imaging
Present with marked depression or deterioation of GCS
Main threat: increased ICP
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Headache, vomiting, depressed mental status 
Posturing and vital sign deterioration
 Bradycardia, hypertension, abnormal respirations
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Ultimately, can lead to brain herniation
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Repeated fundoscopic examinations are
important to look for papilledema
 Especially for patients with coma or seizure
 May not be present initially
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4 possible types
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Uncal herniation
 Innermost part of
temporal lobe moves
over tentorium
 Exerts pressure on the
midbrain and CNIII
 Leads to ipsilateral pupillary
dilation
A 12-year-old boy is brought to the emergency
department after being struck by a car. On physical
exam, he is unresponsive and has a large abrasion
over his forehead. His heart rate is 100, respiratory
rate is 8 breaths/min and shallow, and blood
pressure is 130/80. His pupils are unequal. Of the
following, the MOST appropriate INITIAL step is to:
A. Administer tetanus prophylaxis
B. Infuse 20 mL/kg of 0.9% saline
C. Obtain head computed tomography scan
D. Provide assisted ventilation
E. Administer mannitol
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ABCs FIRST!
Cervical spine precautions
Oxygen
Ventilation as needed to keep pCO2 34-45mmHg
 Hyperventilation has a limited role
 GCS<8 = intubate
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Drugs
 Cardiovascular support
 Anticonvulsants for seizures
 Medications to decrease ICP
 Mannitol
 Hypertonic saline
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Hospital admission
 Any depressed skull fracture
 ICI
 Normal CT scan but persistent symptoms (persistent
vomiting, severe headache, abnormal mental status)
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Emergent Neurosurgical consultation
 Depressed skull fracture and any ICI
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D/C home?
 Normal CT scan (or no CT scan indicated)
 Resolution of symptoms
 Child is easily aroused to light touch, normal baseline mental
status; normal neurologic exam
 If vomited: can now tolerate PO fluids
 Reliable caregiver
 No concern for inflicted injury
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Always review symptoms concerning for ICI!
 Return for: persistent or worsening headaches,
development of vomiting, change in mental status or
behavior, unsteady gait or clumsiness/incoordination,
seizure
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Arrange follow up (even if by phone) in 24 hours
Wake up?
 For low-risk mechanism, no LOC or mental status changes,
<1 episode of vomiting, no non-frontal scalp hematomas
 Observe, do not need to keep them awake, check them
periodically
 No data available for waking child up
 If concerning mechanism or prolonged symptoms:
 Can wake up every 4 hours: child should be able to recognize
parent and surroundings and appear alert
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Subluxation of the radial head
Typical patient:
 Age < 6 years
 History of pull on the arm by caretaker, sibling, etc
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Patient holds arm partially flexed and pronated
 **refuses to move it voluntarily**
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Reduction is initially painful but discomfort
quickly resolves and patient begins moving the
arm voluntarily
If uncertain of diagnosis or if reduction is
unsuccessful  xray!
Name this type of fracture:
A. Buckle fracture
B. Greenstick fracture
C. Nursemaid’s elbow
D. Salter-Harris Type 1
E. Salter-Harris Type 4
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Bones tend to BOW rather than BREAK
Buckle (torus): compression fracture
 Metaphyseal fractures
 Circumferential compression but no periosteal rupture
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Greenstick
 Incomplete fractures of diaphyseal or metaphyseal
bone
 Intact bridge of cortex and perisoteum on the
compression side
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Plastic deformation: in very young children,
neither cortex may break
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20% of all childhood fractures occur at the physis
Can disrupt bone growth
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Clavicle fracture
AC separation
Injuries that affect vasculature
You are seeing a 5 yo boy who complains of right arm pain
after a fall while jumping on the bed. He is holding his
right arm against his body and is unwilling to move it. He
has no deformity or swelling of his right arm, but he does
have a tender swelling in his mid-clavicle. You obtain a
radiograph which shows a midshaft clavicle fracture. Of
the following, you are MOST likely to advise the parents
that:
A. Complications include ulnar nerve palsy
B. He should be tested for osteogenesis imperfecta
C. His right arm should be placed in a sling
D. Surgical reduction will be needed
E. The injury typically heals in 8 to 10 weeks which will be
done in foster care because you are reporting them to
OCS
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Common fracture of childhood
Majority are mid-shaft or distal
Caused by fall or direct force onto
lateral shoulder (with arm adducted)
Presents with pain, deformity, swelling, unwilling
to move arm
Rare complications: brachial plexus injury (more
common with distal fracture)
Treat:
 Immobilization with either figure of eight bandage or
sling
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Adolescent male athletes
Fall onto shoulder with
arm adducted or direct
blow to lateral shoulder
Ranges from partial to full
separation
Swelling and tenderness
over AC joint; pain with
arm elevation and
crossing over across chest
Treatment:
 Partial: immobilization
 Complete: surgery
Normal Shoulder
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60% of elbow fractures
in children
High incidence of
neurovascular injury
 Nerves: radial, median or
ulnar
 Vascular: brachial artery
 More common with
posterolateral
displacement of distal
segment
 Look for pallor and
worsening pain
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Tibial fractures: watch for compartment
syndrome in the distal lower extremity
Scaphiod fracture of the wrist: at risk for
ischemic necrosis
Posteriod sternoclavicular dislocations:
dislocated proximal clavicle may compress the
upper airway or subclavian vessels
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Prior to the development of various thermometers, a
temperature of 98.6 became synonymous with
“normal” body temperature
Body temperatures vary depending on multiple factors
 Method of assessment (axillary, oral, rectal, tympanic)
 Mean range of 97.5-98.6
 Time of day: lowest in morning, peak in early evening
 Individual factors
 Age (slightly higher in younger infants)
 Sex
 Physical activity
 Ambient air temperatures
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There are various methods used to measure body
temperature…consistency is important
Axillary
 Skin temperature lags behind core temperature, especially
early
 Low sensitivity, often inaccurature and imprecise
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Oral method
 Safe and comfortable in kids > 5 years
 Less lag time and more accurate than axillary
measurements
 Affected by temperature of recently consumed foods or by
evaporative effects of mouth breathing
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Rectal temperature
 Has long been accepted as the gold standard of indirect
measurement
 Standard of care in febrile neonates
 Less deviation by environmental factors
 Uncomfortable
 Associated with cross-contamination
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Infrared tympanic membrane thermometry
 Quick, comfortable, cost-effective
 Blood supply to the TM is similar to that of the
hypothalamus, so measurement is thought to be closer to
core body temperature
 Accuracy remains debatable
You are evaluating a 4 month old baby with fever
up to 101.5 for one day. On ROS and physical
examination, there are no localizing signs for the
fever. What is your problem definition?
A. 4 mo F with otitis media
B. 4mo F with urinary tract infection
C. 4 mo F with fever of unknown origin (FUO)
D. 4mo F with thermometer malfunction
E. 4mo F with fever without a source
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Fever without localizing signs on the physical exam
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Both the differential diagnosis and the management differ
depending on the age of the child
Infants < 3 months
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Immature immune response and may no be able to contain
certain infections
Do not consistently show signs of a “localized” cause for
fever, so they often undergo lab evaluation
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< 28 days = FULL septic evaluation
70% have infectious cause identified, majority are viral
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10-12% of febrile infants have bacterial illness
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UTI, meningitis, sepsis, bacteremia, osteomyelitis, septic
arthritis, PNA
Pathogens: GBS, Listeria, Salmonella, E. coli, Staph aureus
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3-36 months
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Most common age for febrile illness, but up to 60% have a
“localized” bacterial or viral cause
40% of cases do have fever without a source
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Primarily viral that requires only reassurance and careful
follow-up
Occult bacterial infections are still present but less common
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Bacteremia…depends on immunization status
UTI
 Prevalence from 2-9%
 More common in young girls, least common in
circumcised males
 If suspected…obtain catheterized urine culture
Pneumonia
You are telling mom how to treat your 4mo patients fever
at home (once you determine that she is at low risk for
serious bacterial infection and that she likely has a
virus). What antipyretic agent do you recommend?
A.
B.
C.
D.
E.
Ibuprofen or another NSAID
Acetaminophen (Tylenol)
Both Ibuprofen and Tylenol alternating with each other
q3 hours
Neither…give the baby an ice bath
Neither…wipe the baby down with alcohol
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Should begin with restoring the nutrients and water lost
during the onset of the febrile phase
Proper hydration
 Comfortable environment
Sponge bathing with tepid water only provides marginal
temperature reduction and often causes discomfort and
shivering
Cold water or rubbing alcohol should NOT be used because it
leads to vasoconstriction…which does not allow for heat
dissipation
 Alcohol can be absorbed through the skin and leads to
toxicity
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Acetaminophen
 10-15 mg/kg every 4-6 hours
NSAIDs (most commonly Ibuprofen)
 5-10 mg/kg every 6-8 hours
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Do NOT use in children < 6 months of age due to the risk of
interstitial nephritis
Similar safety and analgesic effect for moderate-severe pain
Ibuprofen is a more effective antipyretic and provides a longer
duration of antipyresis.
No current evidence indicates that alternating drugs is either
safe or more efficacious than single-drug therapy.
This is a _________ degree burn.
A.
B.
C.
D.
E.
First degree
Second degree
Third degree
Fourth degree
Fifth degree
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First degree burns
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Superficial
Dry
Painful to touch
Heals in < 1 week
Ex: prolonged exposure to sunlight
Second degree burn
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Partial thickness
Pink or mottled red
Bullae or frank weeping on the surface
Usually painful unless classified as “deep”
Heals in 1-3 weeks
Ex: commonly caused by scald injuries, brief exposure to heat
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Third degree burn
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Most serious
Appears pearly white, charred, hard, or parchmentlike
Dead skin (eschar)
Superficial vascular thrombosis can be observed
PainLESS
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A superficial burn wound that extend to less than 10%
of the TBSA can usually be treated on an outpatient
basis UNLESS abuse is suspected
 Apply cotton gauze occlusive dressing
 Protects damaged skin from bacterial contamination
 Eliminates air movement over the wound (decreases pain)
 Decreases water loss
 Change dressings daily
 Topical antibiotic before dressing is placed for prophylaxis
 Most common = silver sulfadiazine
 Daily clinical inspection and wound culture, if necessary,
should determine when the wound is healed
 Typically within 2 weeks
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More extensive or severe burns require inpatient
management, typically at a specialized burn center
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Initial management
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Initial assessment and removal from the scene
Aggressive fluid resuscitation
Nutritional support
Airway management
Prevention and treatment of complications
 Sepsis is major cause of mortality
 Burn shock and burn edema
 Hypermetabolism
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Pediatric electrical burns are typically related to contact
with household, low-voltage sources like electric cords and
wall outlets (110 Volts)
Burns
 Direct contact burns
 Flash contact = current strikes skin but doesn’t enter the body,
associated with soot
 Arc-exposure = body becomes part of the electrical current
 Associated with deep tissue burns and internal organ involvement
 Extent of injury may be underestimated
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Complications (more likely with high-voltage…>1000V)
 Infection…so MUST ensure immunization status
 Arrhythmia (asystole and ventricular fibrillation)
 Compartment syndrome, rhabdomyolysis, renal damage
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Decontamination of the wound is the most important step in
preventing infectious complications
Tap water, sterile water, and sterile saline are all safe and
effective
Pressure irrigation
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4-15 psi using a syringe and splash guard
100mL/cm of wound
Effective at removing most bacteria and foreign material
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Removing foreign material is essential to minimize the risk of
infection
 Wound should be explored for retained foreign bodies
 Heavily contaminated wounds (“road rash”) should be
scrubbed.
 Anesthesia may be required to achieve satisfactory
cleaning.
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Once the wound has been evaluated, decontaminated,
and repaired, an appropriate dressing should be applied.
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Wounds heal best under slightly moist conditions
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Application of topical antibiotic ointments (bacitracin) and
an occlusive dressing
Dressing can be left in place for 24-48 hours
Change once or twice daily
Wounds that cross joints may require splinting or bulky
dressings to minimize movement and tension on the
wound
You are evaluating a teenage patient with extensive dog
bites to the left lower leg and foot as well as the right
hand…he got these when breaking up a dog fight with
his friend. He is unsure of his immunization status, and
his parents are on vacation out of the country, so he can’t
ask them. What do you need to do for tetanus
prophylaxis?
A.
B.
C.
D.
E.
Nothing…you aren’t worried about tetanus at all.
Tetanus immune globulin only
Tdap vaccination only
Both Tdap and tetanus immune globulin injection
Call a consult to ID…you have no idea! (Both Dr. Begue
and Dr. Seybolt are on vacation…ahhhhh!!!)
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Clinical Manifestations
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Most are plantar surface wounds from nails
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Infected puncture wounds that result from a nail through a
tennis shoe should be evaluated for possible Pseudomonas
aeruginosa infection
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Punctures also occur in other parts of the extremities,
trunk, and head
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Particular attention should be paid to wound depth,
possible retained foreign bodies, and risk of infection
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Inspect and remove superficial debris
Neurovascular evaluation
Copious irrigation
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High pressure irrigation is contraindicated because it may
trap bacteria or debris deep within the puncture site
Radiographic evaluation for retained foreign body
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X-ray
Ultrasound: highly sensitive
CT scan
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Higher risk of infection
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Older than 6 hours
Occur from bites, particularly mammalian bites
 Cat >> human > dog
 Should heal by secondary intention
Retained foreign body or vegetative debris
Extend to a significant depth
Human bites on a clenched fist (inoculation of the MCP
joint capsule)
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Most can be managed in the outpatient setting with
antibiotic dressings and warm soaks.
Oral antibiotics only for puncture wounds with a high risk of
infection
 Augmentin OR Clindamycin and Bactrim if PCN allergic
for bites to the hands or feet
Close follow-up
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Any fever, wound redness, swelling, pain, or pus should
prompt re-evaluation to rule out persisted foreign body or
infection
 Staph aureus
 Strep pyogenes
 Pasteurella multocida and other anaerobes (mammal bites)
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More serious infections may need additional imaging and IV
antibiotics
 Cellulitis
 Abscess
 Osteochondritis
 Osteomyelitis
Surgical consultation for potential debridement or retained
foreign body removal should be considered for wounds that
are refractory to medical management
Two very brilliant past pediatric residents (Dr. Kathy and Dr.
Adrienne) walked into the room of a patient with a forehead
laceration that extends slightly to the bridge of his nose.
They decide to use tissue adhesive to repair the small wound.
What could they have done to prevent gluing their patient’s
eyelids together and having to remove a few eyelashes to get
them apart??!! They wish they didn’t have to worry about
getting sued by the patient’s dad…who is a lawyer!
A.
B.
C.
D.
E.
Hook the patient up to an EKG to monitor for arrhythmia
Consult their co-residents Dr. Chelsey and Dr. Nicole to help
pry the eyelids apart.
Try to rinse off the adhesive with some tap water
Apply petroleum jelly or vaseline to the eyebrow and
eyelashes beforehand to prevent the adhesive from sticking
Repeat their 3rd year of residency!
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Evaluate the laceration for foreign material and for any signs
of neurovascular damage
Anesthetics
 Topical LET
 Subcutaneous injection of lidocaine through the opening
of the wound edge
 No epinephrine for fingers, toes, penis, pinna, nose
 Regional nerve blocks
Anxiolysis
 Benzodiazepines (PO or intranasal Versed)
 Distraction techniques
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Timing of closure
 Face: within 24 hours
 Anywhere else: within 6-8 hours
Tissue adhesives
 Less painful, reduced procedure time, comparable
cosmetic outcomes
 Recommended for
 Linear lacerations
 Low tension
 < 4cm in length
Simple interrupted repair
 “Rule of ones”
 Removal: 3-5 days for face and scalp; 10 days elsewhere
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Lip lacerations
 Require special care if the injury crosses the vermilion
border
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Technique
 Approximate the vermilion border with a nonabsorbable or “stay” suture.
 Failure to do so will result in a poor cosmetic outcome
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An infra-orbital or mental nerve block along the lower
gum line may be considered to reduce tissue distrotion
for lip lacerations
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Occur in up to 8% of children with cutaneous wounds
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Wound dehiscence
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Delayed healing
Poor cosmetic outcome
Potentially serious morbidity
Tension on a wound overcomes the tensile strength of the
repair
Can be minimized by splinting high tension wounds and the
appropriate choice of material for repair
Wound infection
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Higher risk
 Extremities, joints
 >12-24 hours old
 Crush, tear, bite, and puncture wounds
Please see the Morning Report PowerPoint entitled
“Bites” on the Chief Resident Webpage. It covers
most of the additional content specifications for
management of animal and insect bites in detail.
•Hymenoptera stings
•Life-threatening reactions include hypotension, wheezing,
laryngeal edema, and other signs of anaphylaxis
•If a patient has one anaphylactic reaction to hymenoptera,
he should be reffered to AI (and given an epipen, of course)
•Immunotherapy with insect venom is 98% effective in
preventing subsequent reactions