Is he wheezing or stridor-ing?

It is always a confusion for me between wheezing vs stridor ( probably mainly because I  do not look up enough ). So what is the difference?

From PubMed :

Hmm..so wheezing is stridor? Not quite yet ( subset does not equal to similar )

1) Wheezing is normally heard in expiration ( although can be inspiratory or biphasic ); stridor is the reverse - heard best in inspiration

2) As wheezing is normally heard in expiration, it typically points to diseases in intrathoracic compartment ( i.e bronchi, bronchioles etc ), and stridor typically points to diseases in extrathoracic compartment ( i.e trachea, epiglottis )

3) And because wheezing typically suggests lower airway pathology, it is heard best over in chest, while stridor is heard better in neck ( logically )

4) One more thing is that stridor can be heard without a stethoscope, like this http://www.youtube.com/watch?v=Zkau4yHsLLM and this http://www.youtube.com/watch?v=1Enq2BvX9aw - the characteristic musical sound is typical of stridor

So what is the significance of hearing wheezing and stridor?

Wheezing - think of 3As

- Asthma, Anaphylaxis ( reactive processes )

- Aspiration of foreign bodies

- But remember asthmatic doesn't always wheeze, in fact the disappearance of wheezing in asthmatics equal impending respiratory arrest !! I call it 'paradoxical wheezing' as the airway is become more and more obstructed, the wheeze becomes softer and softer

- CHF can also cause wheezing in kids

- Rare causes like vascular ring which clamps your lower airway ( esp part of trachea located in the thoracic cavity, other symptom includes dysphagia when the esophagus is also clamped down )

Stridor 

Epoglottis/Larynx - Acute epiglottitis, croup ( laryngotracheobronchitis ), laryngomalacia, post-intubation laryngeal injury

Trachea - Foreign Body Obstruction

References
Fundamentals of Lung Auscultation
Abraham Bohadana, M.D., Gabriel Izbicki, M.D., and Steve S. Kraman, M.D. N Engl J Med 2014; 370:744-751
http://www.nejm.org/doi/full/10.1056/NEJMra1302901

Wheezing and stridor Hollingsworth HM. Clin Chest Med. 1987 Jun;8(2):231-40. http://www.ncbi.nlm.nih.gov/pubmed/3304813