nbmeanswers.com will be going offline for ~hour for some updates! we’ll be right back! --the webmaster (2:17am) ❤️

NBME 20 Answers

nbme20/Block 2/Question#42

A previously healthy 32-year-old woman is brought ...

Preload

Login to comment/vote.

 +0  upvote downvote
submitted by loopers(1),

Vomiting blood and cool skin indicates this is a type of hypovolemic shock. To understand shock, remember that 1) BP = TPR x CO 2) CO = SV x HR 3) SV = EDV - ESV In hypovolemic shock, you are losing fluid, so stroke volume is decreased and end diastolic volume is decreased. Decreased EDV means that the "filling volume" is decreased, which also means the preload will be decreased (https://www.cvphysiology.com/Cardiac%20Function/CF007). Also, skin is cool because you're decreasing SV --> decreased CO --> Ang II/ADH/etc is released to vasoconstrict increaseing resistance. Since there is increased resistance, there is less blood flow causing skin to be cold/clammy.

hello  Patient in hypovolemic shock - the clues are low BP and COOL skin. Hypovolemic shock is caused by fluid loss. The patient has decreased preload b/c of fluid loss, i.e. there is decreased blood volume returning to heart --> thus decreased preload. +2  

 +0  upvote downvote
submitted by hello(49),

Patient in hypovolemic shock - the clues are low BP and COOL skin. Hypovolemic shock is caused by fluid loss.

The patient has decreased preload b/c of fluid loss, i.e. there is decreased blood volume returning to heart --> thus decreased preload.

endochondral   why not dec SVR? +  
sup  @endochondral w/ hypovolemic shock you would see increased systemic arterial resistance as arteries will constrict to try and bring BP back up. +  
eacv  @endochondral dec SVR it typicaly of septic shock. +