A video on lung compliance. Hopefully this will give you a good intuitive idea of what compliance is, and how it relates to mechanical ventilation.
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@supreetkamatagi18314 жыл бұрын
All your videos so great and really appropriate the effort thank for doing all these videos .
@amthaikratai6 жыл бұрын
Thank You very much for those videos. Liked it very much. Concise to the point.
@atlantic7949 Жыл бұрын
Hysteresis is due to the property of surfactants. Their molecules are more apart during inspiration, leading to slight attractions between water molecules the surfactant is in between trying to reduce surface tension. In expiration, surfactant comes closer together and prevents that water-to-water attraction, reducing surface tension. So inspiration and expiration follow the different pressure-volume loops. This property of surfactants is the reason why the lungs don't collapse at the end of expiration. Without surfactants, your lungs collapse like in Neonatal respiratory distress syndrome or ARDS where surfactants are reduced/diluted.
@hanifmahmud92949 жыл бұрын
It really has given intuitive idea....Good work..Thanks.
@HafizahHoshni8 жыл бұрын
goooddd you're just beyond great! i watched all your videos! thanks a lottt :)))
@RespiratoryReview8 жыл бұрын
+Hafizah Hoshni My pleasure! Really glad the videos are helping!
@srikantagangopadhyay88127 жыл бұрын
Very useful presentation.... Regarding the hysteresis loop, I have a confusion. Sir, what is the cause of this different lung volume in inspiration and in expiration, at a certain point of pressure? That is what is the cause of Hysteresis?
@tubeysr2 жыл бұрын
You can think of it like inflating a baloon. Inspiration is more actively blowing the air, against the resistance and surface tension. While as deflation is more of an easier passive like process, with less resistance and more uniformity. Its more of physics.
@user-om8mm2xr1x5 жыл бұрын
There is something I'm really struggling to understand: why would the graph look so different on the way back (exhalation)? You stated what happens during Hysteresis, but really didn't give the logic behind it. You gave a good example with the balloon to describe the inflation phase, but this analogy is not valid for the exhalation phase (according to pascal law at constant temperature, V1*P1=V2*P2, regardless of the direction, inflation or deflation). Am I wrong? If so, where?
@brandonwei69235 жыл бұрын
I'm pretty sure it has to do with rate of surfactant removal as the lung volume decreases.
@Rene-uz3eb2 жыл бұрын
You are not measuring the volume inside the lung, the volume is measured under atmospheric pressure, so the equation is not going to help you. The hysteresis is kind of scary too. Note this is not normal lung function to expand under positive pressure. It seems to say your lung is a bit flabby after the expand or needs a lot more time to regain it's shape, because remember, exhalation is already 5x slower than inhalation, which seems pretty unnatural to me. Normal breathing it's more 1:1. Actually this would almost be a proof: under positive pressure, lung loses so much elasticity that it takes 5x as long to exhale than normal. At least that's my working hypothesis right now I don't see a flaw with it.
@boogahed6 жыл бұрын
So in regards to Emphysema and PF patients. Due to different lung compliances would you expect one to be on a higher pressure than the other>I would expect a much greater volume assisted breath for the latter; or am I way off
@RespiratoryReview6 жыл бұрын
Azmo So emphysema tends to cause very compliant lungs (unless they become hyperinflated) so they will get a large tidal volume for a given pressure in PC, or a low pressure generated when delivering a given tidal volume in VC. Pulmonary fibrosis is associated with poor compliance. So will get a smaller tidal volume for a given pressure in PC, or a higher pressure generated when delivering a given volume in VC. I’d suggest watching the video on pressure/volume relationships in volume control, that might help clear things up. Thanks for watching!
@boogahed6 жыл бұрын
Thanks for reply will check it out. I think i meant a much lower pressure supported breath (not volume) would be needed for Emphysema due to improved compliance. I ask as we've been using BiPAP for COPD pt's; very difficult to work out correct PS and PEEP; particularly if have apnoeas as well
@danielhelfer57618 жыл бұрын
You had it correct, the resting point is at FRC, not RV.
@RespiratoryReview8 жыл бұрын
+Daniel Helfer Thanks for your comment! The diagram is supposed to show difference in compliance from lowest lung volume (RV) up to TLC. I used 'resting' lung volume, and it was a bad choice of words. I said FRC almost instinctively after saying "resting lung volume". This would not be resting lung volume. The P-V curve starts at RV and goes to TLC. At FRC the small airway closure + surface tension would not be as present (and wouldn't produce the poor compliance curve we see below the LIP). Sorry for the confusion.
@SathishKumar-td2ei Жыл бұрын
Wt about ASV mode
@Rene-uz3eb2 жыл бұрын
Thank you very much for providing a basis for the consequences of the positive pressure mechanics. Now that makes sense. So you need 3x more pressure for the same air volume with a ventilator than when breathing normally because of positive vs negative pressure. The lungs were built for the latter obviously. Like we know what high blood pressure does to blood vessels. 69% of over 65 year olds intubated die on the ventilator. The ones sent home have now twice the mortality rate than unintubated. It seems this procedure should be applied only to prevent impending death, forget sedation, and take them off the ventilator after a few hours if what caused the breathing issue can be stabilized enough. Why the hell don't they have iron lungs anymore (maybe a more sexy version), using negative pressure? That wouldn't cause any damage. The whole theory about recruiting bla bla seems to be not feasible anyway with the high pleural pressure. So if the patient can still mechanically move their lungs to effect negative pressure, then that would appear to be much better at oxygenating them than positive pressure ventilators. Why not focus on opening airways without ballooning the lungs? How are the collapsed alveoli supposed to heal if they are being stretched like balloons, just to overcome the surface tension (due to lacking surfectant? Figure out how to replace surfectant then. Or clear pathogens that can interfere with surfectants like candida. I just bought a dirt cheap 10g Ozone generator on Amazon. Works great. Ozone kills candida. As this is not doctor approved (though ozone therapy is very much a real thing, at the same time they say it's a pollutant and bad for the lungs..), I will test this out on myself for the next few days.
@Rene-uz3eb2 жыл бұрын
I suppose pneumothorax would be an exception, where a lung is detached from the chest cavity so to speak and negative pressure won't transmit. Since it's always only one lung affected at a time, and I doubt under positive pressure ventilation that the thorax pressure can heal/normalize, it might be better for survivability to have the functioning lung do double duty until the body restores negative intrapleural pressure to the other lung?
@Rene-uz3eb2 жыл бұрын
Doing great with the ozone. Slight irritation but I'm pretty much overdoing it. 5-10 minute timer a few times a day for a 10g generator inside a small apartment would probably be sufficient. I've cranked it up to 30min intervals every couple of hours or so yeah.
@tubeysr2 жыл бұрын
Please don't experiment on yourself especially with O³. There were reasons why we shifted from iron lungs to positive pressure ventilation. Read and study the basics in detail. You have a good out box thinking, but use it rationally.
@Rene-uz3eb2 жыл бұрын
@@tubeysr I stopped using ozone since it was hard to make out any benefit. It's still good to clear your place of mold if you step out for an hour.
@thetechnerd16178 жыл бұрын
nice video
@asrove29533 жыл бұрын
Can you not speak louder?
@rudyardmagpie4 жыл бұрын
Obama left 142 judges position vacant because he thought Hillary would win !