Hello and welcome back to the Deep Dive.
Today we have a very specific, very high stakes mission.
We're stepping directly into the shoes of a resident, you know,
someone preparing for their MD anesthesiology exams, and we're
zeroing in on the Gujarat University curriculum.
Which is now for being pretty rigorous.
Exactly. And we're looking at a topic
that is, I think, an absolute favorite of examiners because
looks so deceptive on the surface.
You know, it seems simple. It's just a Scoe, right?
But it's a minefield, a complete minefield of physiological and
logistical challenges. So today we are doing a
definitive deep dive into the anesthetic management for ERCP
or endoscopic retrograde Cholango pancreatography.
It's a mouthful. It is.
And to help me untack all of this, to really act as our
virtual senior faculty member and guide us through the Viva
traps and the theory, I'm joined by our expert welcome.
Thank you. It's great to be here.
And you're absolutely right to frame this as a mission, because
when you look at ERCP from an exam perspective, especially for
a board like Gudrat Universities, you have to look
beyond just the rocedure. It's more than just the
technical steps. O much more.
You're not just learning how to push propofol, you're
demonstrating that you understand not operating room
anesthesia or orinara. You're showing you get the
Physiology of the prone position, the pathology of liver
failure, and the critical importance of airway safety in a
dark radiation filled room. A dark radiation filled room.
That's the image. It is this is a topic where they
test your judgement, not just your book knowledge.
They want to know if you can think on your feet when things
go wrong. That sets the stage perfectly.
I think we've all been there. You see ERCP on the list for the
next day and you think, oh nice, an easy sedation case.
But the literature and certainly the exam questions, they suggest
the complete opposite. They do.
It's one of the highest risk procedures we do outside the
operating room. OK, so let's start where every
good exam answer should start. I'm going to break this down
really rigidly today into parts A through H to mimic the
structure of a, you know, a gold standard exam answer.
Let's begin with part A, introduction and exam framing.
Let's do it. So if I'm sitting across from
the examiner and they just ask what is the RCP, I can't just
say it's a scope, I need that one mark precise definition.
What are we looking for here? Precision is absolutely key.
You want to sound like you've read the standard texts like
Miller, so you should define ERCP as a specialized technique,
one that combines both endoscopy and fluoroscopy to diagnose and
treat conditions of the biliary or pancreatic ductal systems.
OK, endoscopy plus fluoroscopy got.
It But here's the key phrase, the one that really gets you the
mark is that it involves the endoscopically guided injection
of contrast media through the duodenal papilla, specifically
the ample of a better to visualize these ducts.
Right. So it's that hybrid nature, part
scope, part X-ray that really defines it.
Exactly. And you must mention the
contrast injection. That's the CNP in ERCP Chilencio
pancreatography. Right.
Of course. So for the exam, we need to
pivot quickly from the definition to the indications.
We can't list every single one, but we need to show we
understand the, you know, the scope of the procedure.
How do we categorize these effectively for a written
answer? The best way is to divide them
into diagnostic and therapeutic. But, and this is a big but, you
must emphasize the therapeutic side because that's where the
real anaesthetic challenge lies. OK, so why is that?
Well, on the diagnostic side, you're, you know, looking at
biliary obstruction, maybe stones, maybe strictures or
you're investigating A pancreatic mass.
That's fairly straightforward. But the examiner's much more
interested in the therapeutic maneuvers like what things like
sphincterotomy where they're cutting the sphincteravati or
placing A stent to relieve jaundice or stone extraction and
even laser liltotripsy to break up a large stone.
These are the things that turn a diagnostic look see into It is
effectively A surgical procedure.
With surgical risks, precisely. Risks of bleeding, perforation,
pancreatitis. If a student only lists
diagnosis of jaundice, they've missed the whole point.
The point is that we're often actively intervening and that's
why they need us there. Which leads us directly to the
why? You know why is this such a high
yield exam topic? Why do examiners seem to love
asking about ERCP? Because it's the perfect storm.
I mean think about it from their perspective.
You've got 3 high risk components all rolled into one.
First you have the patient factor.
The patient is likely sick. They might have obstructive
jaundice, cholangitis, maybe even full blown sepsis.
OK, so a sick patient. That's box 1.
Box 2 is the environmental factor.
You're placing them in a hazardous environment.
The Nora setting, it's dark, there's radiation, so you're
wearing lead, the machine is huge and you're crowded out by
the gastroenterology team and their equipment.
You're often literally pushed into a corner.
You are. And finally, the third box, the
rocedural factor, the position. The patient is almost always
prone or semi prone. So you put it all together.
You have a sick patient face down in the dark, sharing an
airway with a gastroenterologist who is actively manipulating a
large scope in their pharynx. When you put it like that, it
sounds terrifying. It should be respected because
if you lose that airway, you are in serious, serious trouble.
That's why examiners ask about it.
They want to know if you respect that risk.
A sick patient face down in the dark.
That's the mantra before we move on from the framing.
How does this usually appear in the exam?
What formats should you, the listener, be preparing for?
You need to be ready for three main formats.
First, the short note. This is usually titled something
like Anesthetic challenges in ERCP or Nora for ERCP, pretty
straightforward. Second, you can get a long
question or a structured question for maybe 10 or 15
marks. That will be a clinical
scenario. Discuss the anesthetic
management of a 60 year old male with obstructive jaundice posted
for ERCP. Right, the classic case based
question. And 3rd the Viva or the OK CE?
And in the Viva it will almost always focus on your decision
making. They'll ask why did you choose
general anesthesia over sedation for this patient Or your patient
saturation suddenly drops to 85%.
What do you do? They want to see your thought
process under pressure. So you need to be versatile, you
need the book knowledge for the written and the clinical
reasoning for the Viva. That's it exactly.
Excellent. Let's move into Part B
procedural and patient challenges.
And this is the absolutely essential section according to
our outline. Let's start with the position
you mentioned prone. Why is the prone position such a
specific physiological problem for us in this context?
The prone position is it's technically demanding and it's
physiologically altering. As you'll read in Morgan or
Miller, ERCP is usually performed prone or in the
swimmer's position which is semi prone to allow the endoscopist
better orientation for cannulating the biliary duct.
So it's for their benefit, not ours.
Never for ours. Physiologically, this completely
changes the mechanics of breathing.
When a patient is prone, their chest wall and their anterior
abdominal wall are bearing weight because it restricts
their movement. So what happens to chest wall
compliance? It has to decrease.
It decreases significantly. So practically speaking, that
means you need to push harder. You need higher pressures to get
the same volume of air into the lungs.
Exactly. You're going to see higher peak
airway pressures to achieve the same tidal volume, but it goes
deeper than that. Think about the abdomen.
If the abdomen is compressed, it pushes the diaphragm cephalid up
towards the head. Which compresses the bases of
the lungs. Right.
And that reduces your functional residual capacity, your FRC.
This is the critical part. If your FRC drops below your
closing capacity, the small Airways in the dependent parts
of the lungs start to collapse. That creates atelectasis in
shunting. And shunting means VQ mismatch
and hypoxia. And that's why these patients
can desaturate so quickly if they aren't being ventilated
properly, it's a set up for failure.
OK, that's the Physiology. What about the logistical issue?
The practical problem. This is the examination core
point. Limited access.
Once that patient is turned over and draped, you cannot easily
access the airway. You can't see the face, you
can't see the eyes to check for pressure, and you certainly
can't do effective chest compressions.
It's a huge commitment turning them prone.
It is if the endotracheal tube dislodges or if a patient under
sedation obstructs. You can't just fix it quickly.
You can't just pop in an LMA or do a jaw thrust easily.
You have to stop the entire procedure, get everyone's help
and turn them over in an exam answer.
You have to use the words remote and inaccessible when describing
the airway. Remote and inaccessible.
Got it. Let's talk about the duration of
the procedure. Is it predictable?
Not at all, and that's another major challenge.
A simple stent exchange might take 20 minutes, but a complex
lithotripsy or a really difficult cannulation where they
just can't find the duct, that can take 2, maybe 3 hours.
So you're stuck in this limbo. Total limbo, the
gastroenterologist is always saying.
Just five more minutes, and that can go on for hours.
This unpredictability makes sedation titration incredibly
difficult. If you give a large bolus of
propofol thinking it's ending, and then they decide to do
something else, you could have an apnea.
Patient or the opposite you underdose the patient moves at a
critical. And they cause a perforation.
Exactly. It's a very fine line to walk.
And we're doing all of this in the Nora environment.
You know we aren't in our comfortable OT with bright
lights and all our gear perfectly arranged on booms.
No, this is non operating room anesthesia at its most
challenging. The room is darkened for the
fluoroscopy. You're wearing a heavy lead
apron, which is fatiguing over a long case.
Your anaesthetic machine is often pushed to the foot end of
the bed or to the side to make room for the sea arm and the big
endoscopy tower. So your own equipment is remote
too. Your equipment is remote.
Your patient is remote. Your airway is remote.
Miller's chapter in Nora really emphasizes that close claims
analysis, you know, lawsuits, shows a much higher proportion
of death and permanent brain damage in Nora settings compared
to the OR. Wow, why is that?
It often comes down to inadequate oxygenation and
ventilation that just wasn't caught in time.
The dark room mentality, the noise, the distractions can lead
to missed clinical signs you can't see, subtle chest
movements. You rely entirely on your
monitors. O we have a difficult position
and a difficult room. Now let's add the third piece,
the difficult patient we mentioned jaundice.
What are the specific patient related risk factors we need to
flag for the exam? The big one, the one you must
discuss, is obstructive jaundice and the associated liver
dysfunction, and the first thing that should come to mind is
Coagulopathy. OK, bleeding risk.
Right. Patients with biliary
obstruction can't absorb fat soluble vitamins from their gut.
Vitamin K is fat soluble, so they develop a deficiency in the
vitamin K dependent clotting factors 27 I and X.
So their INR goes up. Their INR goes up, but here is
the nuance. For the high scoring candidate,
you must mention the concept of rebalanced hemostasis.
Rebalanced hemostasis, OK, unpack that for us because
historically we just looked at the INR and you know, panicked.
Right. And we still need to be
cautious. But the historical view was, oh,
the INR is high, they're anticoagulated, they will bleed.
But newer evidence, which is discussed in text like Miller,
suggests that while they're pro coagulant factors are low,
They're anticoagulant. Proteins like Protein C and
protein S are also low because they're made in the liver, too.
So the whole system is down regulated, but it's balanced.
It's rebalanced, yes, but it's a fragile balance.
In the exam you must still acknowledge the clinical
bleeding risk. If the INR significantly
prolonged, say over 1.5, you still treat it with vitamin K,
but you should mention this concept to show a deeper
understanding. Very good point.
We also see sepsis mentioned a lot in the sources, specifically
cholingitis. Yes, and you should know Charcos
triad. Can you name the components?
Fever, jaundice, and right upper quadrant pain.
Perfect. If your patient presents with
that triad, they have ascending cholangitis, They are septic.
And what does sepsis do to your hemodynamics?
It causes massive vasodilation. They're peripherally shut down
but centrally vasodilated, so they're SVRS in the boots.
Exactly, they are vasodilated and hemodynamically unstable.
Now imagine inducing anesthesia in that patient, especially when
they're prone. It's a hemodynamic tightrope.
You give a little bit of propofol, there are systemic
vascular resistance drops off a Cliff, and because they're
already volume depleted from this sepsis, they crash.
It's a recipe for profound hypotension.
It is, and if the examiner mentions Reynolds pentad that
adds hypotension and altered mental status to the triad.
That means the patient is in septic shock.
That is a huge red flag that screams resuscitate before you
sedate. Resuscitate before you sedate.
I like that, and I imagine obesity plays a pretty big role
here too. A.
Huge role obesity and obstructive sleep apnea, or OSA.
Miller flags these as high risk predictors for sedation failure.
If you try to sedate an obese patient with OSA in the prone
position, it's a disaster waiting to happen.
Why specifically? Their heavy chest wall
compresses the lungs, they're already reduced FRC drops even
further, their pharyngeal tissues collapse the moment they
get sedated, and you can't get to their jaw to do a jaw thrust
because they're face down. These are the patients where you
should be thinking about securing the airway with an ETT
from the very start. It sounds like for obese OSAGA
is almost mandatory. In my opinion, for an exam
answer, it absolutely is. The risk of sedation is just too
high. OK, so we have framed the
problem beautifully. Now let's move to the solution
part C, preoperative assessment. The examiner asks, how do you
evaluate this patient? We can't just say history and
physical. We need to be specific and
structured. Correct, you need an ERCP
specific structured approach. You start with the airway,
Morgan's text emphasizes this is absolutely mandatory.
You're looking for the usual predictors of difficult
laryngoscopy, Mamelopodi score, thyrimental sense, neck
movement. But there's a twist.
What's the twist? You're not just asking can I
intubate this patient? You have to ask yourself if I
lose this airway while they are prone, can I rescue it?
If the answer is maybe not, then you have a very low threshold to
intubate them electively at the beginning.
So the rescue potential is the key factor.
It is. You also need to check mouth
opening. It needs to be greater than 3
centimeters, not just for your laryngoscope, but for the
endoscope itself to pass easily. Good.
Point And what about the liver and coagulation assessment that
we just touched on? What specific tests are we
ordering? You want a full liver panel,
bilirubin, obviously, to assess the degree of obstruction.
Albumin is crucial because it tells you about the synthetic
function of the liver. How well is it actually making
proteins. A low albumin is a sign of
chronic liver disease and malnutrition.
And of course the INR. And what's our trigger point for
the INR? When do we act?
If the INR is prolonged, say greater than 1.5, the source
material specifically attacks like long and short cases,
advises administering vitamin K, usually 10 milligram, and you'd
want to give it for one to three days preoperatively if you have
the time. If it's an emergency, you might
need fresh frozen plasma. OK.
What about the renal side? You mentioned a specific renal
risk with jaundice. Yes, hepatorenal syndrome.
This is a fascinating bit of Physiology and a great thing to
mention. In Aviva.
These patients are very prone to acute kidney injury and it's
driven by endotoxemia. Endotoxemia.
Yes, normally bile salts in the gut blind endotoxins from gut
bacteria. In obstructed jaundice, no bile
reaches the gut, so these endotoxins are absorbed into the
portal circulation. They trigger a massive
inflammatory response which causes intense renal
vasoconstriction. Combine that with a hypotension
from sepsis or your induction agents and the kidneys just shut
down. That's a deadly combination.
Is there a preventative step we can mention to impress the
examiner? Absolutely.
First you check their baseline creatinine and electrolytes.
But a high level detail mentioned in long and short
cases is the preoperative administration of Lactulose or
oral bile salts. And how does that help?
It binds the endotoxins in the gut, preventing their
absorption. It's a very specific, proactive
measure that can reduce the risk of postoperative renal failure.
It shows you're thinking about the pathophysiology, not just
the anesthetic drugs. That is a fantastic clinical
parole. Now here's a concept that comes
up again and again in the sources.
The full stomach. Even if these patients have
followed fasting guidelines, are they really?
Empty. No, and this is a major Viva
trap. The examiner might say the
patient has been nil by mouth for 8 hours.
Is it safe to proceed with sedation?
And the safe answer is to express caution.
Why? For several reasons.
As a text like Yowen Artuzio points out, these patients often
have delayed gastric emptying or gastroparesis from their
underlying illness, or they might have a functional bowel
obstruction. Furthermore, during a procedure
itself, the endoscopist insufflates the stomach with
either air or CO2 to visualize it.
So even if they were empty at the start, they become full of
gas during the case. Exactly, they are functionally
full. If that patient coughs or gags,
they can regurgitate a large volume of gas and acidic fluid.
So the safest exam answer, the one you should always give, is I
would treat all ERCP patients as potentially having a full
stomach. Aspiration is a leading cause of
medical legal claims in NORAR. That's a clear, unambiguous
directive. Treat as a full stomach.
That brings us perfectly to Part D choice of anesthesia.
This seems to be the biggest debate in clinical practice.
Sedation versus general anesthesia for the exam.
How do we structure this discussion?
You need to present a balanced view, but you must lean heavily
towards safety, especially for the exam.
Let's look at sedation first. This is usually moderate or deep
sedation, almost always with propofol.
The pros are obvious, it's faster, turnover for the unit is
less invasive, and patients tend to recover and go home quicker.
But the cons are significant and you need to quote this Miller
sites data showing that procedural failure rates for
ERCP are twice as high for patients under sedation compared
to those under general anesthesia.
Twice as high. That's a massive difference.
What's the reason for that? The patient moves.
It's as simple as that. If the patient coughs, gags, or
moves while the endoscopist is trying to cannulate a tiny 2mm
duct, they fail. Or worse, they cause a
perforation or pancreatitis. And then there's the respiratory
risk. If you deepen the sedation to
stop them from moving, what happens?
They stop breathing, They stop breathing, and they're prone.
So you're caught in this very narrow, very dangerous
therapeutic window. OK.
So that's a strong case against sedation in complex cases.
Let's talk about the alternative general anesthesia with
endotracheal intubation. Right.
The primary advantage of GA is a secure, protected airway.
You have absolutely control of their ventilation, which is
crucial because the CO2 insufflation can cause
significant hypercarbia if it's not managed.
You provide total immobility, which makes the endoscopist job
easier and dramatically increases success rates.
And the downsides? The downside is it takes more
time. You got an extra 10 to 15
minutes for induction and wake up, and you do risk hemodynamic
instability on induction, which we've already discussed.
However, for the exam, the most important thing you need to know
is the indications. For GA, if the examiner asks
when do you intubate, you need a clear, concise list.
OK, let's have that list. This is an exam favorite
section. What are the absolute triggers
for GA and ERCP? According to a source like
Miller, you should plan for and strongly recommend GA if #1 the
patient has a high aspiration risk.
This includes known gastroparesis, bowel
obstruction, active GI bleeding, you name it.
OK. Aspiration risk.
Two uncooperative patients or those with extreme anxiety.
You simply cannot sedate A combative or agitated patient
safely in the prone position. It's impossible.
That makes sense. 3 prolonged or complex therapeutic procedures.
If they tell you they're planning a pancreatic
necrospectomy, a difficult stone extraction, or treating a
pseudocyst, don't even think about sedation.
If it's likely to take more than, say, 90 minutes, just plan
for Aga, right? Be proactive. 4 Human dynamic
instability, like an aseptic patient securing the airway,
allows you to focus all your attention on managing their
circulation without also worrying about respiratory
depression. And five, A history of failed
sedation in previous attempts. OK, that's a solid list of five.
And I would add a 6th which we've discussed significant
obesity and OSA for me in exam setting that's an absolute
indication airway protection in that group is non negotiable.
Airway protection is non negotiable.
I like that phrase. OK, so we've decided on our
technique. Let's say we're doing Aga for a
complex case. We moved to part E
intraoperative anesthetic management.
Walk us through the airway strategy from the top.
The Golden Rule, the absolute unbreakable rule, is secure the
airway supine. Never let anyone, the surgeon,
the nurse, anyone talk you into turning the patient prone before
you have definitive control of that airway.
So on the stretcher or the table, but flat on their back.
Flat on their back. You induce, you intubate, you
confirm tube placement with bilateral air entry and,
crucially, A capnograph waveform.
Then you tape that tube like your life depends on it, because
the patient's does. Then, and only then, do you
coordinate a slow, careful turn to the prone position with the
entire team. What about superglottic Airways?
I see Lmas use sometimes. Where do they fit in?
The sources like Morgan and other review articles are very
cautious here. Can you use an LMA?
Technically yes, in highly selected low risk cases, a short
simple procedure and a slim fasted patient.
But you have to tell the examiner the risks, which are
the patient is prone. The LMA can easily be dislodged
or rotated during the turn or by the pressure of the endoscoe
itself. If that happens, you can't fix
it easily. Also, and this is critical, a
standard LMA does not offer full protection against aspiration
and we've already established that these patients are at high
risk from the gastric distention.
So for a high stakes exam answer.
For a high stakes exam answer, endotracheal intubation is the
gold standard. For any complex or high risk,
ERCP is a safe, defensible answer.
Got it. ETT is the safe answer.
Now monitoring, we're in that dark room, we can't see the
patient's chest rise and fall very well.
Which is precisely why capttography is mandatory.
Miller's absolutely emphatic on this.
In the Nora section, in a dark room with a patient covered in
lead aprons and surgical drapes, the captagraph is your lifeline.
It is your earliest indicator of apnea, obstruction or
disconnection. And it tells you about more than
just ventilation, right? It does.
It also tells you about perfusion.
If your cardiac output suddenly drops, like from an air embolism
or severe hypotension, your entitle CO2 will drop
precipitously. It's an invaluable tool.
And of course you need all the other standard ASA monitors,
ECG, noninvasive blood pressure, and a pulse oximeter.
But do not start the case without a clear continuous
waveform captor graph. OK, let's talk drugs.
We've got a sick patient with potential liver and kidney
issues. What is our anesthetic cocktail
of choice? For induction and maintenance,
propofol is actually an excellent choice, even
insignificant liver dysfunction. As noted, in long and short
cases, propofol is generally safe.
It has a high hepatic extraction ratio, but it also has
significant extra hepatic metabolism, so it doesn't
accumulate easily. OK, so protocol is fine.
What about? Pain relief for analgesia.
The wonder drug for this particular scenario is REMA
fentanyl. And why specifically REMA
fentanyl over say, fentanyl? It's all about the metabolism.
REMA fentanyl is broken down by nonspecific plasma in tissue
esterases. It's clearance is completely
independent of liver and renal function.
It also has an incredibly rapid on off profile which is perfect
for a Nora setting where you want a fast, predictable wake
up. And fentanyl.
Fentanyl is also safe, but its metabolism is liver dependent so
its effects might be prolonged. In a patient with severe
cirrhosis, you'd certainly need to reduce the dose.
The one to avoid if possible is morphine because it's active
metabolites can accumulate, especially if there's any degree
of renal impairment. Good to know and muscle
relaxants for the GA. If you're doing Aga, you need
profound immobility. The drugs of choice here are
cisaturium or atrocurium. Because of Hoffman degradation.
Exactly. Organ independent elimination.
It breaks down spontaneously in the plasma based on pH and
temperature, so it doesn't care what the liver or kidneys are
doing. If you have to use rocuronium, a
source like long and short cases suggests reducing the dose by up
to 40% in significant liver disease because it relies
heavily on hepato biliary excretion.
You definitely don't want a patient who is paralyzed for two
hours after a 30 minute procedure.
That's a scenario to avoid at all costs.
OK. We have the patient intubated.
We've got our drug plan now we are positioning them prone.
What is on your mental safety checklist for the turn in
positioning? The DNB question source provides
a great checklist here. You should be to recite this one
Eyes. Corneal abrasions are a common
and entirely preventable injury. Tape them shut securely after
turning. Physically checked that there's
no pressure on the globes. OK, eyes first.
Two neck Keep the neck in a neutral position.
Avoid excessive rotation or extension.
You don't want to compress the carotid arteries or the jugular
veins, which could impede cerebral blood flow or increase
intracranial pressure. Makes sense. 3 and this is
physiologically critical, the chest and abdomen.
You must use supports like chest rolls or pelvic bolsters so that
the abdomen hangs free. This is an absolute must do.
And why is the abdomen hanging free so important?
I want to make sure our listener really gets this mechanism down
cold. It's crucial for two reasons,
respiratory and hemodynamic. From a respiratory standpoint,
if the abdomen is compressed, it pushes all the viscera up into
the diaphragm. This splints the diaphragm
dramatically, reduces lung compliance, and makes
ventilation very difficult. And hemodynamically?
Hemodynamically, compression of the abdomen compresses the
inferior vena cava. If you compress the IVC, you
decrease venous return to the right side of the heart, preload
drops, cardiac output drops, and blood pressure drops.
You might see a persistent hypotension that doesn't seem to
respond to fluids. The fix isn't more vasopressors,
the fix is getting the pressure off the belly.
So it's a mechanical problem with a mechanical solution.
Precisely and 4th on the checklist.
Nerves protect the ulnar nerve at the elbow.
It's very vulnerable to pressure injury in the prone or swimmers
position. That abdomen hanging free point
is pure Physiology gold for Aviva.
OK, now we have to go to the dark side.
Part F Complications and crisis management.
This is the absolutely essential section on what to do when
things go wrong. What are the common
complications in ERCP? Well, you have to divide them
into anesthetic complications and procedure related ones.
Anesthetically, the big ones are hypoxia and hypoventilation.
This is most common with over sedation in a prone patient or
an obstructed airway that you can't easily manage.
Aspiration is the other major threat we've discussed.
Hemodynamic instability, specifically hypotension, is
very common because these patients are often septic or
dehydrated and propofol is a potent vasodilator.
And finally, arrhythmias, usually bradycardia, can occur
from vagal stimulation when the scope stretches the duodenum or
esophagus. OK.
And the procedure related complications, the big.
Three you must know are post ERCP, pancreatitis, PPP bleeding
especially after sphincterotomy and perforation.
A retroperitoneal perforation is a surgical emergency.
OK, let's talk about that nightmare scenario we teased in
the intro. You're providing deep sedation.
The patient is prone. Suddenly the sats dropped to
80%. The Captain graph waveform, if
you have one, goes flat or shows a clear obstruction.
What do you do? This is the airway loss and
prone drill. You must have a pre rehearsed
mental algorithm. Step one, recognition and
communication to immediately identify the problem and call
out loud and clear. Stop the procedure.
I have an airway emergency. The endoscopist must pull the
scope out immediately. Stop the stimulus.
Step two, attempt in situ
rescue. While still prone, you try
simple maneuvers. A jaw thrust if you can get your
hands in, suction the pharynx apply 100% oxygen with positive
pressure. If you can ventilate them,
great, you might be able to insert a nasal airway.
Well, what if you can't? What if you're getting no air
entry? Then you move to Step 3, and you
do it without hesitation. The turn.
If you cannot ventilate the patient, you do not waste
precious seconds trying to intubate them prone.
Unless you are an expert with a flexible bronchoscope ready to
go, you must turn the patient supine.
This is the critical life saving decision.
You call for all hands on deck, you flip the patient safely onto
a stretcher or the bed, and you manage the airway in the
familiar supine position where you have access and control.
Turn the patient supine. It sounds so drastic, but in a
crisis, it's the only safe move. It is the only defensible action
if ventilation fails. You cannot effectively
resuscitate or reintubate A prone patient in a crisis.
Time is brain and time is myocardium.
Let's talk about pancreatitis. Is there anything the
anesthetist does to actively prevent that?
Surprisingly, yes, and this is another great fact to drop in an
exam to show you're up to date. Miller sites a major randomized
trial showing that a single dose of rectal indomethacin, a
specific NSEID administered either before or immediately
after the procedure, significantly reduces the risk
and severity of post ERCP pancreatitis.
And the mechanism there. It's thought to inhibit the
inflammatory cascade involving prostaglandins within the
pancreas that gets triggered by the trauma of the procedure.
Fascinating. And perforation.
How would we know that has happened intraoperatively?
It can be subtle. A retroperitoneal perforation
might just present as surgical emphysema, you might feel
crepitus or air under the skin of the neck or chest, or it
could be a sudden unexplained tachycardia and hypotension.
If an air embolus occurs, which is where now that they use CO2
for insufflation, but still possible, you might see a sudden
catastrophic drop in end title CO2 and cardiovascular collapse.
OK, a lot to watch for. Moving on to part G post
procedure care. The procedure is done.
We survive the dark room. What are we watching for in the
recovery area? In recovery, we're watching for
a few key things. First, delayed respiratory
depression. This is especially a risk if we
use sedation with longer acting opioids in a patient with liver
dysfunction who can't metabolize the drugs properly, right?
Second, we are on high alert for signs of perforation.
This would be severe abdominal pain, a rigid abdomen, fever or
tachycardia. The pain of perforation is very
different from the usual visceral ache of the procedure.
It's severe, constant and a surgical emergency.
And bleeding. And pancreatitis, yes, I'd
assume. Yes, watching for hypotension or
Melena for bleeding and rising, amylase or lipase for
pancreatitis, although that usually presents a few hours
later. What about discharge criteria?
When is it safe for them to go home?
For discharge you use standard criteria like the Aldridge score
or the post anesthesia discharge scoring system PADSS.
They need to be awake, alert, hemodynamically stable with pain
and nausea under control. But Miller has a specific note
for our high risk OSA or obesity hypoventilation syndrome
patients. What's the special
consideration? For those patients, you should
specifically check for hypercapnia before you discharge
them. They are prone to retaining CO2
after sedation. If they are still hypercapnic or
excessively somnolent, they need to be admitted for observation
and may even require non invasive ventilation.
Great point. OK, now for Part H comparison
and exam integration. This is where we tie it all
together For the written exam or the Viva, let's build a quick
mental sedation versus GA comparison table.
How would you visualize this for the listener?
OK, imagine a simple table with four key rows.
Row one, airway safety. For GA you write secured and
protected. For sedation, you write at risk
and shared. Clear distinction.
Row 2 hemodynamics. For GA the key issue is
induction hypotension. For sedation it's more variable
but generally more stable unless you have an overdose event.
Row 3 Operating Conditions GA provides complete immobility,
which, as Miller says, leads to higher technical success.
Sedation is plagued by potential patient movement and Row 4 The
bottom line success rate. The literature supports that GA
has a higher procedural success rate, especially for difficult
or therapeutic interventions. That's a perfect concise table
for exam answer. Now the Viva traps.
We've mentioned the INR trap and the full stomach trap.
What are the other common ways a student can fail this question?
Trap number one is under estimating aspiration.
If a student says something like like I'll just use light
sedation for a patient with a bowel obstruction because it's
only a scope, they will fail that station.
You must recognize and verbalize the full stomach risk and have a
plan for it. Trap number 2 is having a casual
attitude. The Nora is easy trap if you
sound dismissive. Oh it's just the GI suite, I
don't need full monitoring or an IV line.
You sound dangerous. The Examiner wants to see more
vigilance in Nora, not less. It's a hostile environment.
You have to be more. Careful exactly.
And trap #3 is forgetting the basics.
If you have a jaundice patient with a high INR and you don't
mention checking their clotting and considering vitamin K,
you've missed a fundamental physiological step of
preoperative preparation. Simple but crucial.
And finally, diagrams. If this is a long written
question, what are we drawing to get those extra marks?
Two simple diagrams will get you a long way.
First draw the prone position schematic, a simple stick figure
prone with rectangles onto the chest and pelvis and label it
chest pelvic bolsters and draw an arrow to the abdomen and
label it abdomen hanging free. It shows you understand the
mechanics. Right.
And the second one. The second is a flow chart for
your crisis plan. Draw a box that says airway
obstruction in prone been an arrow to stop procedure, then
arrow to attempt jaw thrust suction, then a diamond shape
that asks ventilation successful.
If yes, continue with caution. If no a big arrow to a box that
says turn supine immediately and then to intubator rescue airway.
That fully chart shows you have a Plan B.
That is fantastic advice. OK, so let's summarize.
We've covered a huge amount of ground.
What is the high yield? Recap the take home message for
that Gujarat University exam candidate.
You're a 5 golden points. I mean nothing else.
Remember these one ERCP is Eric's to Nora.
Treat it with the respect it deserves. 2 The prone position
dictates your airway management have a very low threshold for GA
and intubation, especially in obese, sick or complex cases.
Got it. 3 Obstructive jaundice means Coagulopathy and renal
risk. Think vitamin K think hydration,
think Lactulose. 4 Capnography is mandatory in the dark.
You cannot see so you must monitor.
It is your sixth sense. And. 5 Have a prices plan.
No when to stop and no when to turn the patient supine.
And the overarching theme for all of this, for your exam
answer and for your career, is to prioritize safety over speed.
The examiner does not care if you are fast, they care if you
are. Safe safety over speed.
A motto for anaesthesia and really for life expert.
Thank you so much. This has been a true deep dive
into the darkroom. It's been my pleasure.
Good luck to everyone sitting the exams.
Go in there with confidence, quote the guidelines and just
remember airway is king. You heard it here first.
Airway is king. Thanks for listening to the deep
dive. Visualize that darkroom, prepare
your crisis plan, and ace that exam.
We'll see you next time.