S2 Ep6: NovPod, a beginner’s guide to anaesthetics, Episode 6: Drugs, part 1

[Music] Hello and welcome back to the Noth Pods hosted by ASC's Ron Air brought to you by the RCOA. Duncan and I have a two-parter for you this time. This is episode six fun farm. So we will try and cover over these two episodes 18 different drugs that you're going to encounter in your novice period with hopefully some survival tips and some background information on them to help you getting into the flow in your first few days. We're joined by the wonderful Rahul Bench Padier who is a ASC's registrar in South London and runs the Sleep FRCA Viper Course and sounds a lot more eloquent than I so going up against him was quite tricky but it was still quite fun to produce a game show format to get over some of the information that you need about drugs. As ever we have links in the bio for further reading so please check them out and they'll be listed at the end of the episode so without further ado enjoy. Welcome Noth Pod listeners to Fun Farm where we have pitted one of our co-hosts Owen he steps into the Thunderdome against our friend and colleague Rahul in order to have battle of who can talk about drugs the best and thus win the coveted golden ET tube. Yeah and this will be a two-parter so first parter is induction IV agents that we will use so blue yellow and red and then second parter will be other common drugs that we use. These schools will be amounting eighties and one of us will be walking away with a golden ET tube. I think it's quite important to say this is not exhaustive lists. This is us trying to introduce some key concepts over to you in a bit of a lighthearted manner but this doesn't constitute everything that you need to know about something. This is me and Rahul off the top of our heads going through on the minute of what we can bring up about a drug. Before we get started we'll go back over what we're going to do for the model answer we want. So you're going to have 60 seconds to talk about the drug and you're going to mark for the correct indications and uses and mark for the appearance of the drug and mark for the dose we give and also the concentration and dilution if that's a specific facet of this drug that's important to know for the novices. A point for the mechanism of action you get two points for two pros of the drug and you get two points for naming two cons of the drug and then there's an extra bonus point if you can speak a fact which has either be fun or interesting and that is completely subjective as to my whims because you've given me the power to be the referee in this episode. We've also got a steer option haven't we Duncan? Yes absolutely. If you pause repeat or stumble two times we're going to say three strikes and you're out you will hear this noise and that means the time will stop and your opponent will have the chance to steal from the next category so if you've got to as far as the pros and you stumbled there then they can steal the points for the cons and a fact. Nice. So what's a play for you? You look a little sweaty in the studio. I'm definitely feeling a bit nervous here. Round one we drew straws before the study episode and Rahul will be going first and we're starting on our lovely induction hypnotic agents. Good luck mate. Was I certainly some warm up my bun? That's good it's working for you. Rahul first go to you. You got 60 seconds I want you to tell me all about our beloved probe foll go. Probe foll is a commonly used anaesthetic drug which can be used for induction and maintenance of anaesthesia for sedation in anaesthetic and ICU practice to absente the hypertensive response to larynxoscopy. It comes as 1 or 2% formulation so 10 milligrams per mil or 20 milligrams per mil in glass ampules stored at room temperature in the drug cupboards and these are usually drawn up neat to the desired specification. A typical dose in a healthy adult is described as 2 to 3 milligrams per kilogram intravenously however the dose will vary depending on the desired effect its mechanism of action is not completely understood however it's thought to be due to potentiation of GABA and glycineurgic activity in the nervous system. There are a number of pros of probe foll including effective induction of anaesthesia and it's reliable and titratable. It also obtains high-potentative responses and it obtains laryngeal reflexes. Right there's three ears from there. Time out. Ah still is too late. Oh no. And let's go 0.5 of a second. I'll take 0.5 of a second. We didn't quite get to the cons and I think that's correct but Owen I'll let you theoretically steal so you will not score any points for this. Well there it is. It's an unlimitimate amount of cons that you can't give with it but I think it means one is that it can decrease your SVR and decrease the effectiveness of your heart beats that can reduce your cardiac output. Another con is you get a pro excised-free movement that can look a bit like a seizure during an emergence from it so I'd list those as two cons that you also shouldn't use it for a long-term station in kids and you can look at how it's to why. Okay. And the fun fact is if you're on an infusion for a long time your urine can turn green. That's fun. Very fun. And it also is because it is soybean and egg white emulsion. If you leave it around out of the fridge, draw it up for a long time. It can have bacteria so you shouldn't do that. But it can be safely given to people in theory with soybean allergies. Very true. We'll go from the top marking through. Indications. You mentioned them all. The only other one is it can be used in the treatment of state sepulepticus. Appearance you got correct. Dose correct and I like the caveat about the depending on the situation you're all to your dose. Mechanism correct. Your pros were correct. Cons we ran out of time and it was a late steel. I think very important cons to talk about and to warn patients about is pain on injection. Very important to warn patients about. Particularly if you're using 2% formulations. Three on mate. That's right. That's right. So moving on. So Owen is you will go? I want you to give me 60 seconds on thio pentone. Go. Thio pentone is a Bob Biture anesthetic that is used for rapid sequence induction and can be used as an ascetic agent anyway. It's also used to decrease the industry pressure so it can be used for seizure control and on a neurotetive care unit. It comes as a yellow powder that gets reconstituted into 20 mils of water so that's 500 milligrams in 20 mils making 25 milligrams per mil. Usually the dose should give in a healthy person is 3 to 5 milligrams per kilogram. Mechanism of action works on chloro channels on GABA and it's pros of that it has a short arm brain circulation. It is also as the pro of decreasing ICP. Cons it doesn't do anything with the larynx. It also is a con that decreases the SVR as well so it can lower the blood pressure. A fun fact is there's a room going around that kill more people at pole harbor than anything else. Actually there was only five increased rate of anesthetic deaths or an association with thio pentone but it was used in quite high concentrations. You went over time with your fact but I wanted you to finish because it was a good fact. It was a good fact. Very good fact. A fact that was then a debunked fact as well. Yeah. So going for the marks indication I think what you were getting at sorry there was it reduces your intranial pressure and so it has a place in neuro protection in head injuries. And the last line on the seizure outbreak. Yeah. Appearance you got it all dose you got and the dilution. Mechanism of action correct your pros were correct. Cons there is a lot of potential for drug error with thio pentone when it's drawn up. It looks like antibiotics and there are multiple case reports of people accidentally giving it instead of an antibiotic in the past. So always label drugs correctly. As you said it doesn't suppress laryngeal reflexes and it can also cause ringaspasm when it's given. And then your fact was very good. Just also to add it can cause severe necrosis if it's given into an arterial line for example or if it extravasates through a tissueed cannula. Yeah. Be careful with thio pentone. One each back to Rahul. Our third induction agent loved by people around the world not always for the best reasons. Give me 60 seconds on ketamine. Go. Ketamine is a fencycloidine derivative that can be used for induction of anesthesia especially in hemorrhage, major trauma and the pre hospital setting can also be used to provide analgesia and sedation for painful procedures. It's normally presented as a clear colorless liquid in glass ampules stored in the CD cupboard so it's locked away in a concentration of 10 milligrams per mil and this is usually presented in a 200 milligram or 500 milligram ampule. The dose will vary depending on the desired effect. However a typical anaesthetic induction dose of ketamine would be 1 to 2 milligrams per kilogram IV or 4 to 5 milligrams per kilogram I am. Thank you. Importantly, ketamine acts as a non-competitive NMDA receptor antagonist, and it provides dissociative anesthesia. And that's just something to bear in mind as it doesn't have a clear endpoint. Pros of ketamine include relative cardiovascular stability as it does not drop systemic vascular resistance and it does not drop heart rate. It can actually increase the heart rate. It also provides analgesia, and it can be given IM as well if there's no IV access. Cons include the risk of emergence phenomena, hallucinations and delirium, and these are quite unpleasant sensations. And that's time. Let's keep going. Okay, we're going to finish it off. Oh, I'm out of steam. Okay, alright. So other cons that you can get with it, is it can actually increase your heart rate and your blood pressure. So if you have patients at risk of decompitating cardiac failure, your indications are good. I think just to re-emphasize is also used in severe bronchospasm, and also it can be used as a pre-medication as well, but that's kind of further down the line in your novice careers. Peerings, as you said, and then the, yeah, just to highlight the concentration difference. Some places have 10 milligrams per meal, some places have 50 milligrams per meal, and some places will have both. So it's always important to double check and if and doubt double check with a second person. Mechanism, you got pros. I like them. Cons. Very good. I think just to highlight cardiac patients and also it can really increase your secretion load. So be wary, not plenty of suctioning at the end of the case. And you can also get emergence phenomena, hallucinations and dysphoria. And the other con is because it's dissociative and aesthetic. So you need to usually use it with a coagent such as metasteline. So the fun facts, Rahul, did you have fun with that? Yes, I think it is. I think it is a fun and interesting fact. Ketamine was one of the main drugs used as part of the Thai cave dive rescue where a team of expert cave divers essentially rescued an entire football team from a complex network of flooded caves. And the reason they used ketamine was for a few of the reasons we've described actually. So one is that it could be given without an IV cannula so they could give it I.M. Another pro of ketamine is that it preserves the airway reflexes and it also preserves spontaneous respiration. So it allowed them to provide essentially sedation or anesthesia while keeping these football players breathing. Because it increases the secretion loading causes salivation, they also gave alongside this I.M. atropine, which I won't talk about too much, but it's just a really fascinating way of how these drugs were used to essentially save these people's lives. Spoiler alert that will come up in the drug episode part two. And they also put them on a CPAP, essentially mask. More of the story is an ecestus save the day as we always do. So I'm pretty sure that's basically what the whole film was about. You just get forwards to the nesca spot, didn't you? We're done with our induction agents. So Owen, it's over to you and we're onto our blue drugs, our opioid buddies. I want you to give me 60 seconds on fentanyl go. Opioid is a synthetic opioid that is used as a suppressant of the hypotensity response to laryngoscopy. So it's a coagent, that could be coagulant as well. And it can be used as analgesia in the acute or chronic pain setting. It usually comes as a clear color solution. 50 micrograms per mil and either a 2 mil or 10 mil container. This mechanism action is the acts on the new opioid receptors being many of them. Pros is that it is quick onset. So between two to five minutes it can come on and it is titratable as well. And it is more usable than morphine in renal failure. Cons is that it can suppress the respiratory drive, which is known with some of its recreational use has caused led to deaths. It also has itchy. I don't have a fact about it, apart from the fact it's been a load of excess deaths in America at the moment. Let's go over the market. Indications. The extra indication is so sedation on ICU. And then also as an adjunct in New York's New Anesthesia, Suspires and Epidurals. Peerance absolutely dose induction. Once to your mind is piquillo. Pros with good mechanism was good cons with good causes it, rather than it is itch. Do you have a fact? It's hard to have a good fact. No fun facts about fentanyl. Rahul. Onto the next. Give me 60 seconds on morphine. Go. Morphine is an opioid drug used in the treatments of acute and chronic pain in perioperative analgesia and also has indications in treatments of breathlessness and end of life care. It can be given via intravenous and all routes and other routes of administration, but its most common preparation is as a 10 milligram in 1 mil ampoule stored and locked in the CD cupboard and diluted into 10 mils of saline to make a 1 milligram per mil solution in a 10 mil syringe. And a typical adult dose in anaesthetic practice would be approximately 0.1 milligrams per kilogram for perioperative analgesia. Its mechanism of action is as an agonist of the mu opioid receptor, but it also acts on other opioid receptors. It also includes the fact that it's widely available and familiar and used around the world. It also is effective for acute and severe pain. Cons include the risk of respiratory depression, itch and the risk of nausea, vomiting and constipation and other generic opioid side effects. Can I be allowed time for my fact? Yes, you can have the fact. Morphine has been used by some quite prominent people, so apparently Florence Nightingale, she used Morphine to treat patients in that context. She also used Morphine for her own chronic pain. Very interesting. So let's go through the marking. I'd almost say flawless victory there. Full marks. So indication appearance, dilution, absolutely correct and the dose mechanism, pros and cons were good. I think yeah, a lot of the opioid pros and cons are quite similar to each other. I think there are a whole host of opioid cons that you can go into. These are just the ones that we're naming, there's other systems that we can go into as well. I think also the ones most commonly complained about by patients. So the last of our blue buddies we're going to go through, Remy Fentanyl. Sixty seconds. Go. Remy Fentanyl is a synthetic opioid that is used as a coagent in total IV anesthesia. It's also used sedation agent on intensive care. It comes as a powder that is made into a clear colorless solution and its dose and concentration can get quite complicated. So I'm just going to tell you that usually gets diluted into 50 milligrams or 40, sorry, 50 mills. Here the b**** have a steel. That's quite annoying. It's quite complicated things to get across. I'll try and think what I was saying, but that's the pressure. The pressure got here. I'll let you steal that one. I'll be trying to do it. It was a great joke, but it's also, it can be very complicated and I'm sure Rahul will explain to us why. Twenty four seconds left. Go. Remy Fentanyl can be provided in 1 milligram, 2 milligram or 5 milligram. Ampules as powder and this can be diluted down to an appropriate concentration depending on what your trust uses locally. It's. Mechanism of action is via a very potent effect on the mute opioid receptors. Pulse are that it is extremely fast acting and fast to wear off and it can be given as a prolonged infusion without increasing the duration of activity and this is known as context insensitive half time. Cons include. That's the risk of. Okay. Twenty four seconds. We've got to, we've got to go to the pros. Rahul, do you have some cons? You're going to get marks for this. One of the main cons is it can cause quite a profound bradycardia and it can cause hypotension. The cons it can cause chest wall rigidity on infusion as well. And then there is also a bit of controversy around whether it can cause hyperalgesia post-operatively. We'll put that into the ether. We're not saying yes or no. So a fact of one of the pros that Rahul mentioned is that it wears on and off quickly its context insensitive. That is because it gets broken down via mechanism that you don't see morphine which is renal or xocode and which is liver. It gets broken down by plasma esterases which means it gets destroyed within about two minutes. It's quite fun. Fun and interesting. There we go. Mark's scheme there quickly run over. So Owen you had indications, appearance than the dose concentration we had Rahul correct it which was good and I think it's just poor to highlight. There is a lot of variation in the use and the dosage and dilution of remy fentanyl. So it's always important to check what you're using and how you're going to use it. That's something I would have double checked when you start drawing it up. Yeah, absolutely. And if it'd always ask again. Mechanism correct. Pros, absolutely and then the cons we've just gone over and the fact. Very good. We're now back to Rahul. We're onto our red label drugs. You're a muscular blockers. Rahul could you give me 60 seconds on rockeronium. Okay. Ready? Steady. Rockeronium is a non-depolarizing muscle relaxant that is used to achieve trickle intubation and provides muscle relaxation for surgery. It can also be used for rapid sequence induction in an appropriate dose. It comes as clear colorless fluid presented in glass. Ampoule kept at fridge temperature for degrees Celsius and is 10 milligrams per mil in concentration and is normally drawn up neat. at CPCode.com. dose of rockuronium for normal intubation would be 0.6 milligrams per kilogram IV for an adult or 1 to 1.2 milligrams per kilogram for a rapid sequence intubating dose. Its mechanism of action is as a non-depolarizing neuromuscular blocker is that it competitively antagonizes astalkolene at the neuromuscular junction and thereby prevents depolarization of muscle fibers. Those include the fact that it can be given in an RSI dose and achieve rapid tracheal intubation. It can also be reversed very effectively with sagamidx. That's time. But if you can do two cons, I'll give you a half point. That's very much possible. Very generous. You try the games when I'm doing whatever I see. There's no bias. It's best for our listener zone. Two cons. So there's a risk of anaphylaxis with rockuronium. I don't think I get any extra points. I'll take his cons there. Okay, fine. For a half point. I would restate the is a cause of anaphylaxis. You've taken away half point. I'm just using my point. I'll use your face to the sun there. Yeah. He looks. No, he looks as the god of the sun. It's okay. Let's go over the marking for that. Indications correct. Periods correct. The dosing and the concentration correct. Mechanism action. Absolutely correct. Your pros correct. So the cons where we felt out of it. Just to reiterate, anaphylaxis can be caused by rockuronium. Pain on injection again. And that can be quite severe and quite sudden onset. Although ideally we wouldn't be giving it to patients who are cautious to feel pain. But there can be a spinal when we withdraw, reflex even in a very anesthetized patient. Yeah, you can get to a good point. Yeah. And it does contribute to critical care acquired weakness. In fact, there's actually been a recent MSRA notification about folkodine cough medicine. They're being withdrawn because there's a risk of sensitizing anaphylaxis to rockuronium. That's interesting. So they're being withdrawn. We are aware that something is interesting for us. Might not be interesting if you've been listening to this. Yeah, we have very sad lives. Over to you, Owen. Our next red drug of choice is atrocurium. You have 60 seconds. Rockuronium's worst looking sibling. Can it go controversy? 60 seconds atrocurium. Okay. Atrocurium is a non-depolarizing neuromuscular blockade agent that is used to obtain control of duchyle intubation. It's also used to cause muscle blockade to facilitate surgery. It's used on ITU to have neuromuscular blockade as well, usually for ventilation reasons. It comes as a clear color solution. It's kept in the fridge at four degrees again. 10 milligrams per meal, usually up to 50 milligrams in five meals. You will give it a 0.5 milligrams per kilo. It's the same as Rockuronium. Pros is that it undergoes Hoffman degradation, so it doesn't build up marine or failure. Another pro is that it can be used reliably. Cons is that it. Disaster. What did you hear that was disaster? That was funny. Okay. I think you had a bit of repetition and pausing in there. Okay. Can I steal? You can steal. The pros, I don't want to hear any pros again. That was a car crash of a pro section after the original strong stuff. So you're on cons. I'm going to give you 10 seconds to get some cons across and a fact if you have one. Ready. Go. Cons include the fact that it can't be given in a rapid sequence intubating dose and a risk of anaphylaxis. It also causes histamine release, which can lead to hypotension and bronchospatism. I don't have a fun and interesting fact. Okay. You stole two points for the cons. So that was. I would appeal if there was a appeal process. I mean, the appeal process has been shut down. Let's go over the marking. Owen, you had a strong start. But your indications were correct even if you did repeat the phrase "neuromuscular blockade four times" who's being merciful. To provide optimal intubation conditions of the secure, critical care, near muscular blockade and also muscle relaxation for surgery. Pierency had to correct. The dose was correct. Pro's is where it kind of all fell down. The fact you have spontaneous breakdown to half-man degradation. That's what's up. I know. So I'm just reiterating. It means that it's good in renal failure. We only have one pro on our mark sheet. I will. Because there is only one pro, Owen, I'm giving you two points for that. Fair game. Then we had Rahul's steel and the cons, very appropriately. Anaphylaxis, histamine release and bronchospatism and hypotension, which isn't anaphylaxis itself, so it can cause both. There's also no rapid reversal for it. Fact. Anyone have a fact? No. Well, it was first made in 1974 at Strathclyde University in Scotland. That's not that interesting. No, no fun. No fun, but you're very selfish. Most of these drugs have made my big farmers out of the Scots. Back to Rahul. We have a special red and black label for you. Saxomathonium. Okay. 60 seconds. Go. Saxomathonium is a depolarising neuromuscular blocking agent. It is presented as used for to facilitate rapid sequence induction and to provide muscle relaxation, for example, for short procedures. It's presented as a clear colorless solution in glass ampule stored in the fridge at a concentration of 50mg per mill, usually 2 mill ampules drawn up neat. However, other concentrations are available. A typical intubating dose would be 1 to 2 milligrams per kilogram IV or 4 milligrams per kilogram I am. Its mechanism of action is that it's essentially two astylcholine molecules joined together. And so what these do is they bind the post-synaptic receptor at the neuromuscular junction. They'd bother for circulation of the muscle, but they prevent further binding of astylcholine and so prevent further muscle activity. Pros include the fact that it can be given in rapid sequence intubation dose. It also has a fast onset and a reasonably rapid offset. That's time. If you can do two cons, you can get a mark. There's a fair few for Saxomathonium. It can cause anaphylaxis. It can be a trigger for malignant hypothermia. There's no specific reversal agent, and then there are a few more which are eluding me at the moment. Well, it can cause muscle pain and it needs to be broken down by plasma. Coalesterases of sometimes families don't have as you can get succsapnea where you can't break down your succsymethatonium and therefore you end up being ventilated for hours or days. And it can also cause life-threatening hypercalemia, especially those who are people who have extra neuromuscular junction such as burns patients or they're so spinal cord injuries. Cool. And the fun fact is it can be given via the tongue. That's so instinct is hung out at us as he speaks. Okay, let's go through the mark scheme. Education is correct. Appearance. Correct. Dose. Correct. Mechanism is actually correct. Pros, as you said, because it can be given I.M. That's also very useful, particularly if you either do not have or lose your IV access during induction. Cons, so you've just listed a load of them. What I was alluding to with succsapnea, it is a inherited genetic polymorphism in which the enzyme that is used to metabolize it is absent or less pumping. And then anaphylaxis, meddling the hypothermia muscle aches, hyperchlemia, particularly in patients who have extra junctional receptors, which is actually burn patients or spinal cord injury patients. And yes, you can inject it in the tongue if you need. Perfect. There is one more drug to do where done with our neuromuscular blocking agents. The last drug of the episode run is a bonus drug to even out. It used to talk to me for 60 seconds about oxygen. Are you ready? Okay. Okay. Go. Option is a therapy that is used to increase people's saturation levels. It can also be used in carbon monoxide poisoning. It has the appearance as coming in a white cylinder or in the pipeline, but usually you can't see it. This is in liters, although actually your fraction of inspired oxygen should be your dose. And that can go from anything from 0%, which is a hypoxic environment, up to 100%. So, mechanism action is that it is involved in aerobic respiration. Proves. Proves is an increases. Out of the frying patterns of the fire, you were doing so well before that. And in a prior using oxygen is it increases saturation. A condes is that if you use it too much, you can get oxidising damage in the lungs. So people on 60% or 100% can really get some damage in their lungs. And the fact is that we actually store it in something called the VRE, which is Waze. We went in cold with that one, so that was horrible. And we're probably giving our own flashbacks to the viber. Let's go through indications for oxygen. You know what? You say carbon monoxide poisoning. I'm feeling really generous. I'm going to give you an extra mark for that as well. And then you said to increase that, we could talk a lot about the indications for oxygen. Hypoxia is one. There's also a very basic one. Appearance. You said we can't really see it, which is true. It's true. It's in the air around us. You can kind of see it. Yeah. And you talked about the cylinder, it's in, so, yep, very good. The dose, you said liters. [BLANK_AUDIO] per minute. I'm not we're recommending we describe people zero percent oxygen and in fact there's lots of things to stop you doing that as an obvious. I think you'd actively have to put someone in a vacuum. Make a fraction of oxidase phosphorylation. Pros increase in saturation. Increases in saturation. I think we'll move on. Maybe that's a quiz. We'll move on. No, okay. Use it to pre-opationate people and buy yourself time for inter-bation. There we go. Increases at near time. That's more of a notch from wash out there. Oh, so I'm going to wash out that nice room with air that's going to buy me some time. It cons. I'm going to give you a mark because you started talking about the hypoxic and oxygen toxicity effects. And another con would be explosive so it needs to be stored correctly. Yeah. Perfect. Okay. Fun facts. Fun facts about oxygen. No. Right, so that brings us on to that brings us on to our scoring for part one and we'll be seeing each other in part two for the golden ETT. I'm looking forward to it. Back on to the results. It's been a bit of a massacre. No, I'm going to lie. Rahul, you've come way with 42 and a half. That's not good. Okay. Okay. Oh, and it's still a respectable score. 32 and a half. Double digit victory. We'll have to see what happens. Part two. That's all I love. The comeback. Means, cleaners on you. Definitely. That's the happy government bill for that one. Congratulations, mate. We're now shaking hands. And that brings us to the end of part one of two for fun farm. I knew you're going up against Rahul was going to be tough but I wasn't expecting this much of a deficit. However, history does love a good comeback. However, moving on from mine and Rahul's competition, I think there's some good links in the bio for you. So there's the e-learning for healthcare modules that we've listed. There's the RCO truck crib sheet. And there's a resource that I know that Duncan and I have used before of the Oxford handbook drugs and anesthesia and intensive care. So as ever, I hope you've enjoyed the episode. I look forward to seeing you at the next one. Bye for now. you you