Flashcards in First Aid Anatomy Deck (22)
Type II pneumocytes
1. produce surfactant
2. act as stem cells
are stimulated during lung damage
Non-ciliated, low columnar/cuboidal with secretory granules.
When are alveoli prone to collapse?
What is the most important component of surfactant?
when does surfactant synthesis begin? how do you know that is matured?
week 26, usually matured around week 35 have to check lecithin: sphingomyelin ration (over 2 is mature)
If the lecithin: sphingomyelin ration is below 2 what would you treat with to speed maturation of type II pneumocytes?
corticosteroids to mother....simulates stress during birthing and thus aids in pneumocyte maturation
Relation of pulmonary artery to bronchus?
RALS-right anterior, left superior
What are the structure perforating the diaphragm?
T10--Esophagus and vagus
T12-- Aorta, thoracic duct, Azygos vein
Diaphragm is innervated by what nerve. How is pain referred to the left shoulder?
Phrenic N. (C3,4,5)
C5 refers pain to the left shoulder
C3,4 refers pain to trapezius ridge
What is anatomic dead space?
Air in conducting airways that do not reach the respiratory zone
Physiologic dead space?
Anatomic dead space + functional dead space
functional dead space--air in respiratory zone that does not undergo gas exchange.
highest functional dead space in apex of the lungs (bc least perfused)
Volume of gas reaching the alveoli
VA=(VT-VD) * RR
What is compliance of the lung?
Change in volume for a given change in pressure
Amount the lung can stretch when forced to
What factors lead to increased oxygen unloading? what type of shift is this on the curve?
Right shift (decreased affinity for oxygen)
high CO2, H+, 2,3 BPG, Cl-, Temp.
What is fetal hemoglobin comprised of and why does it have a greater affinity for oxygen than adult hemoglobin?
2 alpha chains, 2 gamma chains
Lower affinity for 2,3 BPG: thus higher affinity for O2.
What can it be used to treat
Iron is in ferric form (fe3+)--does not bind O2 as readily
Cyanide poisoning (higher affinity for cyanide)
Symptoms of Methoglobinemia? Treatment?
Chocolate colored blood, cyanosis
Cyanide poisoning, how does methoglobin work?
Nitrites are given to convert Hg to MHg
Thiosulfate is given to bind bind cyanide--Thiocynate is renally excreted
When does cyanosis appear?
When deoxy hemoglobin is over 5g/dl
Normal Hb, decrease O2 sat, decrease total O2
decreased Hb. everything else normal. decrease total O2