Authors: Charlotte Davies / Editor: Jasmine Medhora / Codes: RP1, RP3, SLO3, SLO6 / Published: 21/11/2023

There is a lot on RCEMLearning already about Rapid Sequence Induction (RSI) and airway management. It’s useful for everyone in the Emergency Department (ED) to have an awareness of what an RSI is, whether you’ll be performing this procedure or not. We’ve written this blog from the eyes of the “assistant” – this might be the resus nurse, the ED FY2, or a non-airway trained ED registrar. Hopefully, you’ll find it different from all the other airway resources – please send your thoughts, feedback and comments.

If you’d like to watch this as a presentation, it’s available with a focus on ED nurses here. Existing RCEMLearning airway management resources have been collated on our SLO6 blog. If you’d like to learn with some gamification, there’s some RSI anomia cards (with instructions) available here.

What Is RSI?

RCEMLearning talks about an RSI being a rapid sequence induction (of anaesthesia) but there’s no clear consensus about whether the “I” stands for induction, or intubation.



Consider there to be five equally important aspects of an RSI, and we can use these categories to make sure we don’t miss any aspects of the procedure, and we’ll ponder on each of them in turn.

1. Planning

Planning can be split into four areas as per the RCOA checklist which covers preparation of the patient, equipment, team and difficulties.

Fig.2 ICU guideline, DAS


a) Patient and Environment

Knowledge of when an RSI is indicated can help you to predict when it might be used, and start your patient optimisation early. In some, but not all, instances the RSI is being performed because patient optimisation cannot be achieved – but there’s generally something that can be done.



Optimise oxygenation – use your basic airway adjuncts if needed. Turn the oxygen up to 15L/min and make sure there’s a good seal around the nose. Consider nasal oxygen in addition to face mask oxygen. Consider initiating bronchodilators, or supporting ventilation with a facemask, or even CPAP. An NG tube might be useful to decompress the stomach.

Optimise circulation – remember an anaesthetic can be delivered through an IO (tips here). Some IV fluid or vasopressors or inotropes may be useful.

Optimise patient positioning – ensure the ear to sternal notch ratio is perfect – find those pillows now! 



Ensure 360 degree access to the patient, thinking about where everybody, and everything needs to be. It’s often easier to do this before the difficult airway trolley has been moved closer to the patient!

Think about the noise levels – can you enhance likelihood of success by moving people?

Fig.5 via RCEMLearning


Fig.6 RSI Setup checklist via Broome Docs


Ensure your patient monitors are connected and set to cycle BP at least every three minutes. Make sure someone is watching them! Waveform capnography should be connected and ready to go.

Drugs can’t easily be drawn up until a decision has been made about which drugs to use. The September 2023 RCEMLearning podcast talks about making this easier by having all drugs available, but only prefilled syringes of ketamine!


You’ll probably need an induction agent, muscle relaxant, opiate, and then emergency drugs.

c) Plan the approach and the team

Allocate roles ensuring all roles are clear, especially whether to use cricoid pressure or not. If cricoid pressure is to be used, find the landmarks:



Specify intentions clearly, especially around observations. It’s more effective to say “Jude, please keep an eye on the monitors and let me know if the SpO2 drops below 90%”  than “Jude, keep an eye on the monitors… … Sats 98… … 97… … 95…. BP ok… … “.

d) Plan for difficulties

Failed intubation is possible, and there are many airway assessment scores to risk stratify this, but often predicted difficult airways are easy, and predicted easy airways are difficult so always be vigilant. “LEMON” incorporates everything.

Fig.9 via iEM (Click to enlarge)


Look for facial trauma, prominent or jagged teeth that might snag the tube, neck, a beard.




3 fingers between upper and lower teeth of patient with open mouth.
3 fingers between the tip of the mandible and anterior neck
2 fingers between base of the mandible and the thyroid notch.


Fig.11 via LITFL


Obstruction – look for and consider conditions that may cause hidden obstruction like epiglottitis, cancer, trauma, airway burns.

Neck mobility may be reduced in immobilised patients or those with pre-existing neck problems such as ankylosing spondylitis orrheumatoid arthritis If a difficult airway is anticipated, or even if it’s not, have a plan. Luckily, the plan has already been written and standardised for you – make sure you can access the plan and the equipment. For more information, read our reference guide

Fig.12 Difficult Intubation Guidelines via DAS


2. Use of drugs

We’ve probably already got our drugs ready, but now is a good time to consider common side effects to anaesthetic drugs. Be prepared for emergencies such as anaphylaxis.


3. To provide a definitive airway

A definitive airway is a cuffed tube, in the trachea, with proof of placement. Proof of placement needs equal chest rise, equal breath sounds, a good capnography trace and misting of the tube.



No capnography trace = wrong place

As well as needing to be in the trachea, the endotracheal tube needs to be in the right place – and not too far in. If the tube is pushed too far in, it will be in the right main bronchus so only one lung will be ventilated.

Challenging lack of capnography can be difficult and you might need to use your graded assertiveness techniques.


4. Safety

A safe RSI is one with no adverse events.

  • No hypoxia
  • No hypotension
  • No team issues

If incidents happen these should be reported using the standard process in your trust to avoid them in future. Ensuring standardised training with standardised equipment is one way of reducing occurrence of difficult intubations. Some prompt cards or training around what to do if adverse events do happen may also be useful – we made a start below, and are looking forward to your additions.

5. With maintenance of sedation

There’s often so much focus on “getting the tube in” that people forget sedation needs to be maintained. All patients have different requirements for maintaining sedation and it is generally done using an infusion of midazolam or propofol – which needs to be prepared before the procedure starts.

Make sure someone is looking carefully for signs of under sedation:


Further reading: