Low-flow vs. High-flow Supplemental Oxygen (Nursing)

00:00 Hi, welcome to our respiratory video series. Now on this one, we're going to look at supplemental oxygen but specifically FiO₂ and how we control the flow. So after this video, you'll understand a little more about how things work. Now, FiO₂ is the fraction of inspired oxygen. That's what those letters stand for. It means the percentage or concentration of oxygen a person inhales. The FiO₂ of, let's say, this room is 21%. So if I'm in just an average room, room air is 21%. So for giving supplemental oxygen, it's going to be higher than that percentage. So what's the difference between low flow and high flow supplemental oxygen? Let's take a look. Low flow is supplemental oxygen that provides oxygen in a flow rate that are lower than the patient's inspiratory demands. Okay, so this isn't going to have any extreme pressure but it's still going to provide oxygen that's lower than the patient's inspiratory demands. High flow has a much higher delivery rate. So you're going to feel that as it's going in. Now it includes mechanical ventilation which means the patient is intubated and put on a ventilator, high flow nasal cannula, CPAP which is continuous positive airway pressure. Again you're probably familiar with those with people who have obstructive sleep apnea. They wore that mask on their face and has a hose that's connected to a small machine they keep at their bedside and it blows on them at a constant rate, at a rate that's higher, right, centimeters of pressure higher than what they normally breathe in. That's what can maintain those airways staying open instead of obstructing or closing when they sleep. BiPAP is a little fancier than CPAP. Bi means 2 so BiPAP is Positive Airway Pressure at 2 levels, BiPAP. Now this is used for patients. Hopefully we can try to keep them off the ventilator but they have pretty significant respiratory problems but it delivers the air, it is still much higher than what you would normally breathe but it delivers 2 different pressures. As you breathe in, it's at a higher pressure. The one the patient tries to breathe out, it's a lower pressure. Try to decrease the work of breathing while wearing a BiPAP. So, you've got low flow examples and you've got high flow examples but I want to break it down just a little bit more. Because when I'm going to use a low flow system on a patient, you need to know who's appropriate for this and who needs to step it up to a high flow. So this patient will have to need just a relatively stable FiO₂ levels. Okay, so we know they just need a little bit of extra help. They've got a stable respiratory rate and pattern. They're able to breathe on their own, they're breathing consistently, the respiratory rate and pattern are normal. It's not like Cheyne-Stokes breathing. Now, it can deliver a high FiO₂ but it's not as precise because it varies between the size of breaths the patient is taking, you know if we have a nasal cannula on and they're a mouth breather. There's a lot of other variables with this. So you can deliver a high FiO₂ but the precise amount of oxygen that's delivered is going to vary based on the patient's variables. Now, it provides oxygen at flow rates lower than the patient's inspiratory demands. So it's not that high pressure of a higher flow system. So examples of these systems include nasal cannula, simple face mask, face tent, and a non-rebreather mask. Now, high flow systems, we've talked about a couple of them but let's review that. These are helpful for patients who have a respiratory rate or a pattern that varies. Right? We're not depending on the patient to be breathing in and out. We're going to actually assist them at different levels. So, high flow systems would of course include the mechanical ventilator. That's pretty high flow, very technical, lots of specialized settings that we can do that can either breathe completely for the patient or can support their breathing.

04:16 Other ones like the Venturi mask which we often use for COPD patients, we have a nebulizer, a CPAP, a BiPAP, those are other examples of high flow systems. Now, so what? Why does this matter? Why do you need to know this as a nurse? Well this is critically important. You're the one at the bedside. Whether you're in ER, med surg, ICU, telemetry, surgery, wherever you are you're the one who is responsible for observing the patient and see if they're on an appropriate oxygen delivery system. So you need to be aware of the differences.

04:55 You need to know what the logical next step would be. Because when you contact the physician, 00:04:59.600 --> 00:05:04.600 remember you introduce yourself, you're having a situation background assessment and your recommendation. So you need to understand the language of supplemental oxygen. You need to recognize who's appropriate for low flow, who's appropriate for high flow, and when it's time to start backing off those high flow systems back to a low flow.