Stridor

Question 1

what is stridor ?

Answer 1

predominantly inspiratory wheeze due to large airways (larynx/trachea/major bronchi) obstruction

Question 2

what are some causes of inspiratory stridor?

Answer 2

laryngomalacia

supraglottic mass

glottic lesions

vocal cord paralysis

Question 3

what are the causes of stridor in children?

Answer 3

infections

foreign body

anaphylaxis/ angioneurotic oedema

other: toxic damage to membranes - from burns or chemical inhalations

Question 4

what is laryngomalacia?

Answer 4

is the most common cause of stridor in infancy, in which the soft, immature cartilage of the upper larynx collapses inward during inhalation, causing airway obstruction.

Question 5

what infections cause stridor?

Answer 5

croup

epiglottitis

pseudomembranous croup - rare

retropharyngeal abscess

diptheria

infectious mononucleosis

Question 6

what virus causes croup?

Answer 6

RSV

Question 7

what is croup?

Answer 7

inflammation of the larynx and trachea in children, associated with infection and causing breathing difficulties.

Question 8

which organisms cause epiglottitis ?

Answer 8

almost always croup

Question 9

where is the retropharyngeal abscess?

Answer 9

behind the soft tissues of neck

Question 10

what organisms cause infectious mononucleisis ?

Answer 10

virus - can cause upper airway narrowing

Question 11

what is the main difference between adult and child infections ?

Answer 11

children are more likely to get viral infections

Question 12

what history would lead you to think of aspirated foreign body causing stridor?

Answer 12

acute onset stridor accompanied by a choking spell but need to do a CXR to exclude other things

Question 13

what are the main causes of stridor in adults?

Answer 13

neoplasms

anaphylaxis

goitre

trauma

other

Question 14

what are the less common causes of stridor in adults?

Answer 14

bilateral cord palsy - cant open larynx properly

wegener’s granulomatosis

cricoarytenoid arthritis ( RA

tracheopathia

Question 15

what is the most common place for neoplasm in smokers?

Answer 15

larynx

Question 16

what are the other places for neoplasm?

Answer 16

trachea

major bronchi - lung cancers

Question 17

what investigations should be done for stridor?

Answer 17

laryngoscopy (beware in acute epiglottitis)

bronchoscopy

flow volume loop

CXR

CT and thyroid scan

Question 18

what is the X ray good for?

Answer 18

good for excluding things

Question 19

how is laryngeal obstruction treated?

Answer 19

treat underlying cause e.g. foreign body removal anaphylaxis

mask bag ventilation with high flow O2

cricothyroidotomy

tracheostomy - bypassing the obstruction

Question 20

who may have a

cricothyroidotomy?

Answer 20

someone who has maybe had a chemical burn

Question 21

how is malignant airway obstruction treated?

Answer 21

tumour removal

tumour compression

radiotherapy

chemotherapy

Question 22

how is tumour compression done?

Answer 22

intraluminal stent

Question 23

how is tumour removal done?

Answer 23

laser; photodynamic therapy - inject a drug which is inactive but rapidly taken up by fast metabolising cells - shine light and cause cells to die which have the drug in them;

cryotherapy - freeze the tumour with local freezing ;

diathermy - electrical current burns it away ;

surgical resection

Question 24

what are the signs of acute anaphylaxis?

Answer 24

Type 1 (immediate) hypersensitivity (IgE)

Flushing, pruritus, urticaria,

Angioneurotic oedema (lips, tongue→ face, larynx, bronchi)

(abdominal pain, vomiting)

Hypotension (vasodilatation and plasma exudation)→ circulatory collapse (shock)

Stridor, wheeze and respiratory failure

Question 25

what are the causes of anaphylaxis?

Answer 25

Foods eg nuts; shellfish
Insect venom (bee, wasp)
Drugs (eg penicillin is most common and it is usually just a rash, aspirin, anaesthetics)
Other eg latex

Question 26

what is the treatment for anaphylaxis ?

Answer 26

IM Epinephrine (adrenaline)
IV antihistamine
IV corticosteroid
High flow O2
Nebulised bronchodilators
Endotracheal intubation if necessary