[hana]

By definition it is increase in JVP during inspiration and decrease in JVP during expiration right?
so it is a different concept from just having high increased JVP, am I right or not?

My q is;

1-CAN WE HAVE KUSSMAUL IN any condition causing raise in right atrium pressure or no?
i want to know if for having kussmaul beside raised atrial pressure there is need of other factors as well or just high pressure of RA can eventually lead to kussmaul?

the reason i am asking this is i see constrictive pericarditis frequently mentioned as having kussmaul but not other conditions which cause RA high pressure such as TS, PS, P- HTN OR EVEN TR.

2- I SAW IN FA ,myxoma cause kussmaul. i know it makes rise in JVP but kussmaul?
thank you

btw, i do not want to bring tamponade into this discussion cause i read in so many references and i finally i accepted for UNKNOWN reason we do not have kaussmaul in cardiac tamponade!

 

[GGossling]

Hana, I personally think about atrium volume, not atrium pressure, even though they're related.

In inspiration, we decrease intrathoracic pressure and increase intraabdominal pressure. This leads to a rise in venous return from the inferior cava. If atrium is not able to contain the volume of this blood, atrium pressure and jugular vein pressure increase. In expiration, the venous return decreases and atrium pressure decreases.

But, remember, this happens when atrium is not able to contain the volume of the blood, and its pressure increases much more that it would with the same amount of blood if atrium was able to expand.


The conditions you mentioned do not restrict the volume or the expansions of right atrium, even though they rise atrium pressure. This does not mean they don't increase atrium pressure in inspiration. This just means they don't do it enough to inspiratory and expiratory atrium and JV pressure become so different that this becomes fairly visible and recognizable as Kussmaul's sign.


The only explanation for cardiac tamponade I found is the following:
Tamponade is made with blood, a liquid. When atrium pressure achieves the pressure of the liquid that is around it, the increases that would happen if it were a volume restriction are not expressive, because blood is a liquid, and it's able to transfer this (further) increase in pressure to all the volume of the tamponade, increasing atrium pressure much less thatn the needed for Kussmaul's sign. It works as if you were adding this blood not to just to the atrium volume alone, but to atrium + tamponade volume. This leads to much less expressive increase in pressure than it would if was just atrium.



I hope I helped you.

 

[Sabio]

See previous thread

Kussmaul's sign is not about elevated right atrial pressure, it's about improper filling of the heart.

Please read here
http://www.usmle-forums.com/usmle-step-1-buzzwords/463-kussmauls-breathing-sign.html