Hi toshiba1,
Laryngotracheobronchitis is the medical term for croup, a condition
caused most commonly by RSV (respiratory syncytial virus),
rhinoviruses, and influenza viruses. The consition is characterized by
low grade fever, respiratory infection, cough, stridor and
hoarseness. It is known to worsen at night. Stridor (those raspy
scratchy sounds when breathing) and croupy sounds come from an
obstructed airway, from airway lesions and swelling from infection.
Children have a normally small larynx and trachea, making even a small
amount of swelling dangerous.
?The stridor can be defined as a variably pitched respiratory sound
caused by tissue vibration through an area of decreased caliber.? ?The
stridor is worsened while crying or in an excited state, often in the
supine position where the supraglottic structures may collapse
inward.?
http://www.utmb.edu/otoref/Grnds/Stridor-infants-980415/Stridor-infants-980415.html
?The two most common infectious causes of airway obstruction are
laryngotracheobronchitis (croup) and epiglottitis. Both are more
common in children but both can occur in adults. Croup is usually a
viral illness that results in subglottic (tracheal) stenosis.. The
onset is usually over 4-5 days at the end of an upper respiratory
infection. Croup does not usually become life threatening but it can
be if severe. Diagnosis can be made by a PA soft tissue neck x-ray
which will show tracheal narrowing at the top of the tracheal air
shadow (steeple sign). Patients with croup have a variable amount of
respiratory distress and have a peculiar barking cough (at least
infants do).
Croup is normally treated with cool mist and sometimes steroids and/or
aerosolized racemic epinephrine which acts as a topical
vasoconstrictor. The most important thing to remember with croup is
that you must be sure that the patient doesn't really have
epiglottitis which is usually a more serious condition. Epiglottis
usually results from a bacterial infection, frequently Haemophilus
influenzae. The onset is rapid and can progress to severe airway
obstruction within 6-8 hours in infants though usually it takes longer
in adults. Stridor, dysphagia, odynophagia, and drooling (from
inability to swallow) are typical symptoms. Patients with epiglottitis
tend to be very anxious (not to mention their doctors).
A lateral soft tissue neck x-ray is usually diagnostic but if
obstruction is severe the patient should probably proceed to the
operating suite for a controlled intubation by the most experienced
person available rather than risking a complete airway obstruction in
the radiology department. Laryngoscopy should ideally not be attempted
unless personnel and equipment for an emergent tracheotomy is
available. An abscess can also obstruct the upper airway. Symptoms may
vary depending on the location but are usually similar to those of
epiglottitis. Again, a lateral soft-tissue neck x-ray is helpful for
diagnosis and a CT scan is useful if the airway can be protected.?
http://www.midcarolina.org/papers/airway.emerg.html
?Airway obstruction is due to alteration of the upper respiratory
tract (e.g. nasal cavity, nasopharynx, larynx) and lower respiratory
tract (e.g. trachea, bronchi and bronchioles, alveoli) and can derive
from congenital malformations, infectious diseases, trauma and oedema.
Airway obstruction can appear after a simple inflammation of upper
airways and may progressively deteriorate until emergency stage.
Airway obstruction, due to the severity of complications and possible
evolution of hypoxia into cardiac arrest, must be treated immediately.
The treatment is devoted to maintaining patency of airways and
ensuring adequate ventilation. Patency of airways and adequate
ventilation can frequently be obtained only with endotracheal
intubation.?
http://www.picu.it/india/obstructed_airway_marraro.pdf
?The infant's larynx and trachea are significantly smaller than the
adult's. The vocal cords of the newborn infant are 6-8 mm long and
the vocal processes of the arytenoids extend one half of that length.
The posterior glottis' transverse length is approximately 4 mm. The
subglottis has a diameter of between 5 and 7 mm. The trachea itself
is about 4 cm long and as a diameter of 3.6 mm. These dimensions
leave little margin for obstruction in the infant, unlike the adult.
For example, an infant with one millimeter of glottic edema will
experience a 35% obstruction of the airway. In the subglottis, one
millimeter of edema leads to a 44% narrowing.?
?Respiratory distress or stridor immediately after extubation may be
due to subglottic edema whereas distress that starts after two to
three weeks may indicate early subglottic stenosis or vocal cord
granuloma. ?Although radiography is not required in the presence of
these classic symptoms, neck films often show the ?steeple sign,? ?
symmetric narrowing of the subglottic space?
You will need to have MS Word installed to see this page:
www.utmb.edu/otoref/Grnds/ Pedi-Airway-2001-01/Pedi-Airway-2002-01.doc
?The edema and hyperemia in this supraglottic region produce airway
obstruction which can be partial or complete. As the airway
obstruction becomes more severe, the respiratory distress becomes
greater. Because of the proximity of the supraglottic region to the
esophagus, the inflamed epiglottis and the surrounding structures
cause the patient to experience difficulty swallowing, i.e.,
dysphagia.?
?In mild cases of LTB humidification (cool mist) may reduce the airway
narrowing. Sometimes exposure to the cold night air may diminish
symptoms as well. Hearing accounts from parents, who brought their
child out of the house and into the cold night for a trip In mild
cases of LTB humidification (cool mist) may reduce the airway
narrowing. Sometimes exposure to the cold night air may diminish
symptoms as well. Hearing accounts from parents, who brought their
child out of the house and into the cold night for a trip.
http://www.foocus.com/pdfs/Articles/Winter04/BillWoj.pdf
This excellent article is not copyable.
http://www.turner-white.com/pdf/hp_sep03_acute.pdf
?Viral infection of the upper airway results in inflammation of the
pharynx, larynx, trachea and
bronchi. However, it is specifically subglottic inflammation (and
resultant swelling) that compromises the airway in croup.?
http://mja.com.au/public/issues/179_07_061003/fit10207_fm.pdf
?Sleep in the same room with your child for a few nights. (Reason:
croup can suddenly become severe at night.)?
http://www.aurorahealthcare.org/yourhealth/scd-parentcare/getcontent.asp?URLparentcare=%22Croup.htm%22
?Children 5 years old and younger are at greater risk of getting croup
because it's easier for their small airways to swell, making breathing
difficult. Signs and symptoms are most severe in children 3 years old
and younger. Some children may be more likely to develop croup, such
as those who were born prematurely or who have narrow upper airways.?
?Your child may seem to improve the day after the first night of
croup, but don't be surprised if croup returns for the next several
nights. However, once your child has had at least one or two good
nights, you've probably made it through croup.?
http://www.cnn.com/HEALTH/library/DS/00312.html
?Spasmodic croup characteristically occurs at night and tends to recur
with respiratory tract infections. It is thought that it may have an
allergic origin and is irritated by the dry air of a home?s heating
system. This dry air may make the condition worse which explains why
it is seen more frequently in the fall and early winter seasons.?
http://www.yrbhp.markham.on.ca/pdfs/Croup/Croup%20Assessment%20Fall%202002.pdf
?Stridor is often present from birth but may also develop in the first
few weeks; it may be worsened by lying down or by concurrent upper
respiratory infection.?
http://www.rcpe.ac.uk/publications/articles/vol31_no3/O_Joint_Symposium.pdf
Treating Croup
http://www.mothernature.com/Library/Bookshelf/Books/50/32.cfm
So, what would I tell a parent about the cause of croup?:
========================================================================
Your child has a case of croup, a condition caused by a viral
respiratory infection. The reason your child?s symptoms are worse at
night is because she/he is lying down. The airway in a child is by
nature is small, and when infected, the larynx becomes swollen
(edematous) and inflamed, further obstructing the passage of air. Dry,
heated air at night can further irritate the larynx. During the day,
its easy to keep the throat moist, with juice, popsicles, etc. While
sleeping (or attempting to sleep!) the child is not drinking and
keeping the throat moist.
Similar, but not the same, to adults snoring when in bed, due to the
congestion in the airway and the flopping back of the uvula; when a
child lies down, the swelling and irritation obstructs the airway.
During the day irritants, bacteria, viruses and allergens can
accumulate along the ?mucosal blanket? that coats the airway, and
aggravate the throat at night. At night, post-nasal drip also adds to
the irritation of the already narrowed airway of the child, making a
croupy cough worse.
I?d show the parents the following illustrations so they can better
understand a narrowed and obstructed airway.
http://medicalimages.allrefer.com/large/epiglottis.jpg
http://www.snoring.com.au/physiology/physiologyofsnoring.shtml
http://homepage.mac.com/kostudios/Pages/stock%20ENT%20respiratory/croup.html
(Animated)
http://www.biology.eku.edu/RITCHISO/epiglottis.gif
The seventh illustration on this page shows the swelling of the
epiglottis in green, making it easy for a parent to visualize.
http://www.biology.eku.edu/RITCHISO/342notes7.html
Collapsed airway
http://www.cc.utah.edu/~mda9899/Image9.gif
http://www.lifeart.com/lifeart_display/comps/PED01002.jpg
Swollen larynx
http://www.entusa.com/Larynx_Photos/larynx-mass-09012002.jpg
You may be interested in this site on capnography and croup
http://www.capnography.com/Ped/pedg.htm
Hope this is the answer you were seeking. If not, please request an
Answer Clarification, before rating. This will enable me to assist
your further, if possible.
Regards, Crabcakes
Search Terms
Airway obstruction + croup
Laryngotracheobronchitis
croup physiology
croup night + day
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