From the classroom to the emergency room, O.R and beyond. You're joining Trauma ICU Rounds with your host, Dr. Dennis Kim.

Welcome to trauma ICU rounds. I'm your host, Dr. Dennis Kim. Now, in our last episode, we reviewed ARDS Fund, and to follow up, today I want to talk about

the role of positive end expratory pressure or peep, as well as lung volume recruitment maneuvers,

aka LVRs, in patients with ARDS.

In terms of learning objectives, by the end of this podcast, you should be able to, number one,

understand the key determinants of oxygenation in mechanically ventilated patients.

Number two, discuss the benefits and risks of a liberal peep strategy, and we'll discuss

this in the context of the 2004 Ard's Net alveoli paper.

Finally, number three, describe how and why an LVR is performed.

So, when we place a patient on the mechanical ventilator, especially when our patient is in

the throes of acute respiratory failure, our objective

upfront and early is to take over the work of respiration, typically by means of providing full

or complete ventilatory support while maintaining adequate oxygenation and ventilation.

And as we've discussed for patients with ARDS, we typically start with low total volume

ventilation on the order of 4 to 6 cc per KG of predicted body weight and want to limit our

plateau pressures to less than or equal to 30 centimeters of water.

Now, plateau pressures are measured with a brief less than 0.5 second inspiratory breath hold,

and they're a reflection or approximation of alveolar distending pressures

and used to calculate our static compliance, which again is the change in tidal volume

over the change in pressure,

with the pressures being the plateau pressure minus your peep.

Now, another term for plateau pressure minus peep is driving pressure, which many advocate

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