I love structure to my learning, teaching and ways of approaching a problem.
Intubation is no different. This can be a stressful time for everyone and that stress can lead to mistakes.
So let’s learn about the seven P’s that will make the process smoother.
The Magnificent 7!
Paralysis with induction
Placement with proof
First thing we need to think about is the equipment we will need:
Laryngoscope- this is how the person intubating is going to get that tongue out of the way, see what they are doing, find the epiglottis and then the vocal cords for that tube to go through.
Test to make sure the batteries are working!
Endotracheal tube- this is what we are trying to get into the patients airway after all. So we need to make sure that we have the size we want, probably a 7, 8 or 9 for an adult.
Check that the balloon works well and that there is some lubrication on the end so that it passes the through the cords easily. You will also need to be sure that there is one size smaller available in case the first one is too big.
Bag-Valve-Mask- This will be needed both before and during the intubation to make sure that the patient stays well oxygenated.
Make sure it is attached to the oxygen and that it can be fully inflated testing it for any leaks.
Guedel Airways- It may be difficult for the intubator to maintain an airway without also using an airway adjunct.
The guedel comes in an number of sizes all differentiated by their colour. This can be measured by putting it to the patients face to ensure it is long enough to go from the angle of the jaw to the corner of the mouth.
Bougi- Sometimes it can be hard to get the ET tube to go through the cords. It can be tricky to get it to turn the corner when there is one!
This is where the bougi comes in handy. This can pass through the cords and then the ET tube can be slid over it and through.
Not always used but often essential when it becomes tricky.
Patient position- the patients head needs to be as near to the top of the bed as possible so that the incubator can reach them easily without having to strain or find it difficult.
It may be to start with that the patient is sat very upright as they may find the the most comfortable way to breath when they are struggling, but once the process starts they are likely to be laid down flatter.
A very important step if things are going to go smoothly.
Preoxygenation- it is really important to aim to get the patients saturations as high as possible before starting.
The objective of preoxygenation is not just to get oxygen in but also to wash the nitrogen out of the patient and replace it with oxygen.
Nitrogen plays no useful role and if we replace it with oxygen this will give us much longer before those stats start to drop.
We will aim to keep a tight seal on the patient for at least 3 minutes.
Paralysis with induction
Now we are going to get going we are going to need some drugs.
Sedative- patient needs to be sedated and unconscious to allow us to begin. Most commonly I used drugs in my experience are-
Propofol- 1.5-2.5mg/kg. Draw up 1% in a 20 ml syringe and, depending on the patient, some or all of this will be used.
Ketamine- 1-4.5mg/kg. Again draw up in a 20 ml syringe. All or some will be given.
Neuromuscular blocker (paralysing agent)- we need to paralyse the patient so that we can get the endotracheal tube through the cords. Otherwise they don’t relax.
Rocuronium- 600mcgs/kg. Comes in ampoules of 50mg. Draw up two into the same ampoule and most or all of this will be used.
Suxamethonium- 1-1.5mg/kg. Usually comes in 50mg ampoules. Draw up one and all of this will be used.
Vasopressors- due to the action of the other drugs the patients blood pressure may well drop during induction. We might need some drugs to counteract this.
Metaraminol- 0.5-5mg. Commonly made up as 10mg in 10mls (1mg/ml) or 10mg in 20 mls (0.5mg/ml) depending on users preference. Given in small boluses titrating to effect.
Don’t overflex the head!
Two important points here and phrases you might hear. The position of the patients head is very important to ensure that the incubator has the best chance of getting a good view of those cords.
Sniffing the morning air- imagine you have come out of your front door and the air smells wonderful! You put your head forward to take in a good lungful. This is the position we want the patients head in.
Ear to sternal notch- if you look at the image you can see that we have had to raise the patients head so that their ear lobe is level with the sternal notch and their face is perpendicular to the ceiling.
Placement with proof.
We need to be sure that the tube is in the right place! Can be disastrous if not!
So where could the tube go?
Firstly it could go in the oesophagus. This would mean that we were ventilating the stomach and not the lungs. Clearly not what we want. Apart from the impact on their oxygenation this can also make the patient vomit.
So how do we know we are in the lungs. The gold standard is the presence of a good end tidal CO2 wave form. This will be the first thing we look for. If that is there we are happy that we are in the right place.
But we also need to be sure that we have not gone too far with the tube and are only ventilating one lung. This is when we listen to the chest with the stethoscope to ensure we can hear air entry on both sides.
If not then we may have to pull the tube back a little.
Post intubation management
Phew! The tube is in the right place and we can ventilate our patient. Great. Now we need to make sure that they stay that way.
We need to get them on an infusion that will keep them asleep. Ideally this should have been prepared before we started. Let’s get it connected.
Then we need to get them on a ventilator with all the settings that are needed to keep them stable. Commonly at this stage they are put on a volume or pressure controlled mode with mandatory breaths. Let’s be sure that we are giving them the right sized tidal volumes, with airway pressures that are not too high and that they are adequately saturated.
Finally we need to secure the tube with whatever system we use and then put in an NG tube to get any air out of the stomach that they may have swallowed or that we put in whilst we were bagging them.