Procedural anaesthesia is providing IV anaesthesia to allow a painful procedure to be performed. Very rarely it will be performed to rapidly control dangerous behaviour.
It has also been called conscious sedation or procedural sedation but usually we don’t want our patient to be conscious and we want them to be anaesthetised, not just sedated. These terms are largely hangovers from the past when we had to pretend we weren’t really doing anaesthesia in ED.
We don’t usually count giving up to 70% nitrous oxide within the realms of procedural anaesthesia as there is very low risk of loss of airway with just nitrous oxide.
Generally the procedure is very similar to performing a rapid sequence intubation (RSI) just smaller doses of drugs are used, we don’t use paralytics and we don’t stick a tube in the trachea. Otherwise the set up and monitoring is very similar. This is a bit of over kill for procedural anaesthesia, but it ensures you have all the equipment, staff and drugs you need if anything goes wrong, and it’s good practice for the set up for RSIs so it keeps the team slick. You can even use the first part of your RSI check list to set up for procedural anaesthesia, modifying it as required.
This will make sure you remember all the equipment and steps and will keep everyone familiar with your RSI checklist.
Written Treatment Agreement
Unless this is an emergency procedure eg unstable tachyarrhythmia, procedural anaesthesia requires a written treatment agreement or treatment request form (commonly know as a Consent Form).
You need to disuss and document the risks and benefits of the procedure and the anaesthesia. Risk of anaesthesia are: experiencing of pain, nausea, vomiting, inhaling vomit, confusion, hallucinations (depending on the agent used), allergic reaction to drugs, stopping breathing. With any anaesthesia there is a tiny chance of death. The benefits of anaesthesia is that it usually a pleasant, pain free experience with no recollection of the painful procedure.
You may want to make a pre printed treatment agreement form with all of the above alreay on it.
Any bay with suction, oxygen and monitoring could be used. In our hospital we use a resus bay as has all the gear in it already, and again it helps with team familiarisation with RSI procedures.
Generally we like to have at least 3 staff for procedural anaesthesia. An appropriately qualified doc to perform the anaesthesia and watch the patient. A nurse as super can do everything person, helping with preparation, advocating for the patient and monitoring the patient. They can help with the procedure being performed while keeping an eye on the patient. The third staff member is usually a doctor performing the procedure itself. You will need to check what your institutions rules are regarding how many staff are required and what the skill level required is. Generally the doctor performing the anaesthesia will be senior ED registrar (resident) level or above. ACEP allows just 2 staff members to be present, it does not require that 2 doctors are present.
If a consultant is performing the anaesthesia they may briefly help with the procedure while still closely watching the patient.
The choices of medication(s) varies with every consultant and often will vary depending on the patient and procedure. Ask the team leader what they want.
For procedural anaesthesia we are aiming for that sweet spot where the patient is maintaining their airway, breathing spontaneously has a good cardiac output yet has no or minimal experiece of pain.
All medications need to be double checked and labeled (prefilled, prelabeled syringes of medication are ideal) and placed tidally in a tray.
Medication is administered by the doctor performing anaesthesia or by a nurse following the doctor’s direct instruction.
Some docs will push the whole predicted dose of anaesthetic, others prefer to titrate slowly eg asking patients to keep their eyes open or to hold one arm up in the air and stopping drug administration when the eyes close or the arm drops. I prefer to push the predicted dose. Generally we will have more than the predicted dose drawn up in the syringe to allow for top up doses. Doctor’s must make themselves aware of what is in the syringe. We have had 2 episodes of doctors getting over excited and just pushing a whole syringe of the white stuff thinking the syringe contained the predicted dose only.
Also known as Jackson Juice. For a very brief procedure eg cardioversion, shoulder or hip relocation, often just propofol will be used. eg 1mg/kg for a young person, down to 20mg for a 90 year old.
Propofol and Ketamine
For longer or very painful procedures often a combination of ketamine and propofol are used. This may be in a fixed mg:mg ratio (know as ketafol) or titrated separately.
These drugs work well synergistically. Propofol gives good anaesthesia and is antiemetic, it’s down side is that it can cause loss of airway reflexes, hypoventilation and hypotension. Ketamine is very analgesic and dissociative anaesthetic usually with maintained airway, breathing and circulation but can cause unpleasant hallucinations and nausea and vomiting. The combination allows lower doses of each agent and they negate each others negative effects.
As always doses need to be reduced in the elderly. Good anaesthesia for cardioversion for an 89-year-old can be achieved with 20mg of ketamine and 20mg of propofol.
For a young person for a quite painful, longer procedure, eg MUA and plastering of a fracture, I will typically give 0.8 mg/kg of propofol and 0.8 mg/kg of ketamine. If further doses of anaesthetic are needed I will usually just give boluses of propofol alone eg 0.2mg/kg, rather than giving further doses of ketamine to reduce recovery time and to reduce the adverse effects of ketamine. But every patient is different and you need to be flexible titrating against respirations and response to pain. It is reassuring that even when patients appear to be experiencing pain they only occassionally remember cardioversions but it seems they never remember the MUAs or I+Ds
I am not in favour of ketamine only anaesthesia. I have had too many patients, even ones who said as they woke up “Wow, that was amazing”, stop me in the supermarket a week later and say “Hey doc, that drug was awful.” One of our anaesthetists tells us of having ketamine only anaesthesia then spending the whole night hallucinating he was being repeatedly run over by cars. A tad unpleasant.
I do rarely use ketamine only anaesthesia for rapid control of dangerous (to themself or others) patients eg ketamine 5mg/kg IM.
Especially when ketamine is used it is good to add an antiemetic eg ondansetron 4mg or 0.15mg/kg.
There are many other drug cocktails used.
Allergies (especially to anaesthetic medication)
Past medical history (yes, I know that is redundant) especially anaesthetic history, family history of anaesthetic problems, obesity and reflux
In my opinion this patient is not a candidate for ED procedural anaesthesia. I gave him 100µg IV fentanyl and 70% nitrous but we couldn’t get his shoulder relocated. He went upstairs. (Turned out an anaesthetist with large gonads just gave him a truck load of propofol and face mask ventilated him while a very good ortho reg struggled for 15 minutes to relocate it).
Obese patients are our nemisis. They occlude their airways at the drop of a hat, they are difficult to ventilate or intubate and they are high aspiration risks. Just don’t go there for procedural anaesthesia unless it is emergent eg haemodynamically unstable arrhythmia. Let someone else take that risk.
Last ate or drank, the patient does not need to be fasted according to ACEP, but we may modify things if we know he’s just had 10 beers.
Events: make sure you know the full story about this patient before you put them to sleep. Is that dislocated shoulder actually attached to a broken neck?
Feel the neck, identify the cricothyroid just in case it all turns to custard. Assess neck mobility and thyromental distance. We want4 of the patients fingers (guestimate with your own fingers) between the top of the thyoid cartilage and the bottom of the front of the mandible with the neck extended. Make sure the patient can protrude their lower teeth infront of their upper teeth and that the mouth opens wide (at least 3 of their fingers (again guestimate with yours if necessary), how much of the oropharynx can you see:
See Mallampati score
Is their anything on their face that would make them hard to ventilate with a BVM?
If the patient is obese ramp them so their tragus is higher than their manubrial-sternal joint (blue line in the picture below)
If you are dealing with a lesion on the patient’s back put the patient on their side, not face down.
While you are positioning the patient refresh you memory regarding the bed controls: work out how to tip the patient head down if they vomit
One good IV or IO line is enough for procedural anaesthesia. Make sure it is well secured.
Cautionary tale: beware the IV line in the foot. Some of my colleagues in a land big and red were anaesthetising an elderly patient for a cardioversion. They gave some propofol, then some more propofol, then some more. Eventually all the propofol made it to her heart and brain and she had a PEA arrest. They had the good sense to cardiovert her and give good CPR till the propofol wore off and she made a full recovery.
Some people have IV fluids running (which reassures us the IV line is working and can be used to flush drugs) others find this to be another tube that gets in the way and is probably unneccessary. Ask your team leader.
It’s OCD overkill time.
Size and have out on top of the resus trolley (or under the pillow) all of your airway equipment:
Suction – tested
Supraglottic device (eg intubating LMA)
Scalpel (I always keep one in my pocket while at work too)
Capnography tubing (we don’t routinely use this in our hospital for procedural anaesthesia as the powers that be have decided the consumables are too expensive, but have it out and ready to be used)
Laryngoscopes – tested
On the patient:
Nasal prongs oxygen running at 2L a minute till they are asleep then crank it up to 15L/min.
Non-rebreather oxygen mask with high flow O2. 3 minutes of preoxygenation.
Monitoring x 3 or 4 (depending on whether your hospital uses capnography (see above)
Audible oximetry (“the beeps”)
BP set to go every 2.5 minutes
+/- capnography depending on your hospital’s policy
The above rigmarole sounds complicated but takes very little time for a well trained team.
Push or titrate drugs
It’s finally sleepy time.
The anaesthesing doctor, or delegated nurse, pushes or titrates the anaesthetic drugs (see above)
Further top up doses may be required
Procedure, monitoring and apnoeas.
The patient is closely monitored and the procedure is performed.
Have a decent amount of chest and belly exposed so that you can watch the respirations.
Don’t panic if the patient stops breathing. With the above preparation they will be able to tolerate a long period of apnoea. If needed you can ask the doctor performing the procedure to inflict some pain or you can do a firm jaw thrust and the patient will usually start breathing again. If not grab your BVM and start ventilating. Use other airway adjuvants as needed. Nasopharyngeal airways are very well tolerated and will sort out most airway occlusions.
The anaesthetic is not necessarily over when the procedure is finished. Especially if opioids or benzodiazepines are used this can be the most dangerous time for apnoeas – the pain has stopped but the drugs are still onboard.
The patient must have one-on-one observation until they are talking clearly. Once they are talking take the oxygen mask off just in case they vomit. Have a vomit bowl handy. Once the patient is talking they should be kept on monitoring (reduce the BP frequency to q 15 minutes) and watched by reliable family.
The patient is fit for discharge when they can walk independently (or the equivalent for their age and abilities).
Give them verbal and written advice not to drive or operate dangerous machinery until after a full nights sleep and to phone ED if they have any problems.
Ketafol evolution http://eductionlanka.blogspot.co.nz/2013/03/academic-life-in-emergency-medicine_20.html
Facial piercings http://culturewarclasswar.wordpress.com/2012/06/13/the-itch-we-cannot-scratch-imprinted-to-tattoo-body-pierce-and-sun-bathe-in-prenatal-irritationrevulsion-21st-century-and-its-discontents-part-22/
Ramped patient http://crashingpatient.com/resuscitation/airway/airway.htm/