Oxygen therapy and ventilation

The difference between pxygen therapy devices and air way devices. Air way devices is to maintain airway while these devices is to make breathing less vital by increasing oxygen sat So when breathing is compromised the patient doesnt have to breathe well to receive oxygen as sats are increased. But it doesnt help with airway maintainance. Only works if airway is open. Link upto oxygen therapy tute and go though that first ⇒

https://www.notion.so/mbbstree/Oxygen-therapy-and-fluid-therapy-ed0f20259eb944ab91871469c3787a32

——————————- If oxygen sat is low then can be problem with breathing so need more than 21% oxygen like in normal air so that to maintain p02

Aim for just enough to maintain p02 in blood.

Normal person ⇒ 97-99%

Oder ⇒ 94% - 97%

Oxygen cyllinders are usually black with a white top And flow rate controlled by valves (not %) ITs all about suppling oxygen to the air that patient breathes in ...to increase sat of that air from 21% to a level above it ...so hopefully to increase oxygen saturation for the patient. If need to increase sat of the air breathe in must increase flow rate ⇒ so theres high flow oxgen devices and low flow oxygen devices. Which has the oxgen delivery rate and hence alter the % of 02 in the air breathe in. Nasal specs for example has 2-4 litres per minute which is low flow and hence cannot increase the % oxgen much higher. So can only increase little. All of these oxygen therapy deives - low flow or high flow to deliver oxygen and increase % - all of these recieve their oxygen from an oxygen cyllinder. Or even line in the thratre.

Do ABG to check pco2

Be careful of giving high flow and high % oxygen for COPD patients with hypoxic drive. Their p02 and sat is chonically low and so their breathig is driven by this hypoxia. They have an hypoxic drive. So if given high oxygen % and flow rate, the sat in their blood can increase and cause depressed breathing and stop breathing all together! Low flow rate doesnt exceed patients breathing pull but high fow does. Low flow isnt acceurate but high flow guaranttees the percentage oxygen going in if set up properly

High flow sstems can be humidifoed and heat set so not dry or cold

Low flow system have flow rate lower than the inpiratory demand gaining air from the room. So even if 100% oxgen, still its been diluted. High flow system gives off more oxygen volume than the inspiratory demand so the patient will always be taken in air from this - so you can for example set the venturi masks to give a certain percentage of oxygen through the venturi effect so it will always be this that they are inhalign. so if the valve says 40% its always this 40% that is being inhaled since the flow exceed the inspiratpry demand.

Relationshop ebtween nasal canula flow and fi02. fi02 is the fraction of inspired oxygen. the naal canular gives like 4L per minute but the patient takes in 7L er min. So even though 100% oxygen from the nasal canula still 100percent of 4L plus 21% of the remaining so its diluted. And also not accuate and variable - unlike high flow which is fixed.

you can change the fi02 settings without changing the flow rate but veturi suing venturi effect assuming its 100% oxgen being given High flow systems not given for out patients!

Nasal specs

Nasal canula mainatniance ⇒ canula can become clogged so have backuo etc

can increase efficiency = because reservoir so can store up and use more time

can speak and eat

Simple oxygen mask

Also low flow - oxgen % sat can be altered by changing the flow rate inwards. so increase rate if need to increase oxygen - but not very accurate as air can come in from outside too. The mask has a valve to let air out during expiration!

The holes allow for dilution as well as co2 and exhaled air to leave

Venturi masks

Allows high flow and better for controlling the flow rate and therefore the oxygen sat. so can fine tune better.

The valve has the percenttage of oxygen and the flow rate required to deliver this oxygen

There is no air sucked from the sides of the mask...instead theres a venturi effect as above to control the percentage oxygen. Theres a calculation to calculate the percentage oxygen thats delivered. Change the valve to change the oxygen level. Expired air goes out through the other valve found. Venturi masks can also be used as a low flow device depending on how its being used can be used for maintiannce - and used when patient sats decreases during endoscopy but cant eat or speak etc unlike cpap masks

Theres from 24% upto 60% to change oxygen sat.

green has highest flow Oxygen is very drying so its humidified as below

And flow rate is controlled using the valve there. Venturi masks need that adeqaute flow rate to deliver that percentage of oxygen it states! The oxygen delivered is 100% obviously.

Its through distilled water to wet it so its noisy and wet.

Needs to be changed regularly because of infection risk.

Non-rebreathing mask

For higher flow than venturi masks. Its like a normal mask but with reservoir that fills with oxygen to draw on. So there is less drawn on from outside instead comes from the reservois bag so high oxygen percentage

Anyone who needs this to maintain their level of oxygen needs specialist review since something really wrong. This is for intensive care and not a light thing to have rebresther mask. high sats and needs specialist review. Called nonbreather because this has a valve that lets exhaled ait leave so invbreathing high oxygen/. Nebuliser

It has a chamber to put the liquid part of the drug. Then air or oxygen is passed to turn it into a vapour to be inhaled. The valves used here are one way valves

Must investigate such patienst with abgs etc

The ambu bag is also a reservoir and can give high amount of oxygen since it draws on from this reservoir and not air. but in basic life support, no cyllinder so instead you use air .

Nebuliser

can change the oxygen sats

blender to adjust flow rate and oxygen sats Can eat and talk when on this so better than the ventilator Can be used for peads

Using a oxygen cyllinder

the ball shows the flow rate can have cyllinder or liquid oxygen or the machine

Look at the gauge to see how much psi or oxgen is remaining.

The regulator is attached to the tank and that has a gauge to indicate the pressure which reflects how much is left in the tank and then ou adjust the flow rate which opens it. Nasal cannular four and high flow more than that.

Ventilation 101

Oxygenation vs ventilation Oxygenation is about oxygen sats. and giving oxygen to improve this. Ventilation is about actual breathing and more to do with co2 sats and levels that can be found using abg. So air way vs oxygenation vs ventilation

how to monitor oxygenation? (using pulse oxymeter or ABG) How to improve oxgenation? (use high flow or low flow device or increase fi02 in ventikator)

How to monitor ventilation? (using ABG ⇒ co2 levels) How to improve ventilation? (increasing tidal volume or RR)