CHAPTER: Resp Flashcards
Another name for phosphatidylcholine
Lecithin
L/sphingomyelin ratio > 2 = healthy
Where in the airways is:
- Highest R
- End cartilage // goblet cells
- End SM
Med size airways = ↑est R
End cart + GC @ bronchi
End SM @ terminal bronchioles
What goes through at T10 vs 12?
10: esophagus + CN 10
12: red - white - blue
Aorta - thoracic duct - azygous vein
Level at which these bifurcate:
Common carotid
Trachea
AA
CC: C4
T: T4
AA: L4
What value isn’t measured on spirometry and thus messes up a lot of lung vol calcs
RV
Where is Hgb taut vs relaxed
Taut @ tissues = low O2 affinity for unloading
Relaxed @ resp to pick up O2
↑O2 affinity b/c ↓BPG affinity
4 causes of a R shift in the Hgb binding curve
R shift = ↓affinity
- Acidosis: (exercise) ↑H+ to bind Hb = HbH
- ↑BPG
- ↑Temp
- ↑Pco2: think will make O2 unload more to correct this
- Altitude
How does CO poisoning change the Hgb binding curve
L shift - ↑affinity for CO
Describe how methemoglobin is generated + 2 symptoms + antidote
Hgb (Fe 2+) + nitrates or benzocaine (local anesthetic) Convert to Hgb (Fe 3+) = mHg Symptoms: 1. Cyanosis 2. Chocolate blood Antidote = methylene blue
How does the O2 binding curve change with CO?
- Comes down = ↓O2 bound to Hb
2. Faster slope = ↑affinity for CO > O2
Why does myoglobin not show positive cooperativity (aka more linear slope of binding curve)?
B/c monomeric
What is hypoxemia vs hypoxia?
Xemia = ↓PaO2 = dissolved O2
Hypoxia = ↓O2 delivery to tissues
Xemia can lead to hypoxia
Describe V/Q of the lobes of the lung
Top lobe = ↓V/↓↓Q = ↑ratio = wasted vent b/c preferentially vasocontrict away from a low airflow area
Middle w/e
Bottom lobe = highest V + Q but ↑V/↑↑Q = ↓ratio, aka the perfusion is so much greater than vent
Describe change to high altitude:
↓O2 atm = ↓PAO2 = ↓PaO2
↑vent to compensate = ↓PaCO2 = resp alkalosis (time causes comp metabolic acidosis aka excreting HCO3)
↑EPO + BPG to comp
↓PAO2 -> hypoxic vasoconstriction -> pulm HTN + RHF
2 BVs you need to know for nose bleeds
Ant = Kiesselbach plexus
Post/potentially life threatening = sphenopalatine art (branch maxillary art)
What does a negative D dimer tell you about suspected PE?
Not a PE
+ d dimer rules in it, - rules it out
What is Homan sign?
If you dorsiflex pts foot -> calf pain
Sign of PE
3 causes of nasal polyps
- Repeated rhinitis
- CF (kid)
- ASA intol asthma (adult)
What might you biopsy for suspected nasopharyngeal carcinoma//aka what might present?
Cervical LNs
See keratin + (epi) cells w/ lymphocyte background (makes sense since EBV tumor)
Describe etiology of vocal cord nodules that are:
- Bilateral
- 1 unilat
- Multiple unilat
- Overuse - made of myxoid CT
2 // 3 - adults // kids - laryngeal carcinoma = SCC
Smoking, alc, or HPV 6/11 (weird low grade!!)
3 non-lung presentations of TB granulomas
Base meninges
Kidney -> sterile pyuria (pus in urine)
Pott’s… duh you know that
Shape of TB granuloma + cytokine that maintains it
Horseshoe - necrotic granuolma
IFNg
Hemm or ischemic infarct for PE
Unlikely to infarct at all b/c lots co-lat circulation
If anything, hemm
What type of gas causes problems with the bends? What is this disease called if it goes chronic and causes bone necrosis?
Nitrogen bubbles precipitating
Caisson disease
