Acute Respiratory Failure/ARDS

[beatrice1]

HELP! Is ther any difference between Acute Respiratory Failure and Acute Respiratory Distress /Syndrome? I keep reading about both of them and getting more confused. I don't see the differences.... anyone have any information that will help me know both of these??

thanks,

Bea

[ukstudent]

Acute respiratory failure is the inability of the patient to breath/ventilate on their own, so needing increased oxygen and or mechanical help.

Acute respiratory distress syndrome is a type of respiratory failure, but not everyone in failure will go on to develop ARDS. In ARDS the lungs stiffen and it decrease the lungs ability to make surfactant, therefor requiring higher levels of PEEP.

[GilaRRT]

Respiratory failure is a nebulous term utilised to describe inadequate gas exchange. ARDS is a very specific type of respiratory failure.

The specific findings to identify ARDS include:

1) Bilateral and diffuse infiltrates

2) Lack of evidence to point toward left ventricular dysfunction

3) Acute onset

4) P:F ratio of less than 200

Some people consider ALI a "mild" form of ARDS, while others consider ALI a precursor. In any event, a P:F ratio of less than 300 is indicative of ALI.

[meandragonbrett]

ARDS can also be described as a V/Q mismatch.

[GilaRRT]

ARDS can also be described as a V/Q mismatch.

A V/Q mismatch is present along with significant right to left shunting in ARDS. However, V/Q mismatch is another one of those nebulous terms that is associated with many problems.

[meandragonbrett]

Gila,

Exactly what I meant......but not what I wrote! :)

[Zookeeper3]

ARDS is the build up of fluid around the alveoli air sacs due to increased capillary permeability and leak... it's an inflamitory response that prevents oxygenation exchange of CO2 and O2 because of the fluid lying in the spaces.

This type of patient is vented, on high levels of peep and then pressure control, even an oscillating vent that delivers continuous pressure to pass the gradient of increased pressure between the alveolar sacs to open them up an allow the gas exchange.

ARDS, because of the lack of oxygenation to major organs and the high levels of thoracic pressure needed to provide oxygen generally leads to multi-organ failure. These patients have low blood flow to "unimportant" organs like the gut, kidneys, extremities and bones. It's the body's way of trying to save itself, but organs fail as a result.

So you get kidney failure, extremity cyanosis with the need to add vasopressors, clots are thrown, the gut shuts down and TPN is needed, the gut gets ischemic.... paralytics are needed to oxygenate and the gut shuts down and gets necrotic... the bones stopped producing cells for blood....

Now you have lungs down, gut down, kidney's down, extremities throwing clots and blood coagulapothys.... this results in death. Or in the least a trach, peg, and medabolic encepalopathy.... which is my usual ICU patient

Acute respiratory failure is a CHF, pneumonia, non compliant dialysis patient, COPD'er that can be turned around with BIPAP, or a few days on the vent, that does NOT get the inflammitory response that initiates capillary leak in the alveoli that starts the whole cascade I just mentioned.

Complicated, but easy and unfortunately common and and ugly scene.

[GilaRRT]

No problem Mean . Zookeeper, I generally agree; however, ARDS is a form of respiratory failure.

[Zookeeper3]

No problem Mean . Zookeeper, I generally agree; however, ARDS is a form of respiratory failure.

yup, should have stated that, thanks!!!! I got off on my teaching tangent. There was so much more to say... but I get too excited and wordy.

[GilaRRT]

No worries mate.