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Surgery of the week:

Welcome to the Surgery section of the website. This is your one stop shop for brief information you may need to know about surgical procedures as a medical student or a doctor in training. Every week, we will aim to discuss a different condition or procedure.

Topics covered so far:

  • Appendicitis.

  • Girly causes of RIF pain.

  • Diverticular Disease.

  • Renal Colic.

  • NELA

20/03/19 Appendicitis.

So you think you know about appendicitis, but what I have found, is massive variation between texts regarding some of the key points.  So here is my summary, to try and explain it all and highlight the examinable bits.


What is the appendix?

The appendix is a blind ended small tube that extends from the caecum.  According to different texts, the length can be anything from 5cm to 20cm long.  I doubt anyone will test you on that.


Why do we have an appendix?

There are different theories, but no one really knows and it is unlikely to come up in an exam.


Who gets appendicitis?

Varies depending on where you look, basically anyone with an appendix cane get appendicitis, but there are 2 peaks, the first largest one being for people aged between about 10 and 20 years, there is a small second hump between 78 and 85.  With that in mind, if a nana comes in presenting with RIF pain, you might be more likely to get imaging on her to confirm, as she would be more likely to have carcinoma or diverticular disease, than perhaps the younger people.  All interesting but ultimately unlikely to be tested.


So why do we get appendicitis?

The most common cause of appendicitis is obstruction of the lumen, most usually by a faecolith (a bit a hard faecal matter).  By obstructing the appendix, the gut bacteria increase and cause inflammation and infection.  Obviously there are other causes of this obstruction, including anything from cancer to generalised oedema around the appendix.  Never seen that on an MCQ.


Why does the clinical picture in appendicitis vary?

In general, the symptoms of appendicitis are associated with the anatomy.  From the embryological development the appendix is part of the mid gut, and this is experienced as poorly defined central abdominal pain at the early stages.  As the inflamed appendix starts to increase inflammation in surrounding structures, this is experienced as peritoneal irritation which is far more location specific in the Right Iliac Fossa (RIF), and some have irritation to the bladder. 


Appendicitis can be very variable in presentation and the Alvarado score helps quantify the likelihood that the patient has appendicitis, with points for RIF pain (2), low grade fever 37.3 or above(1), rebound tenderness(1), migration of pain(1), loss of appetite (1) partly due to reduced gut motility, and partly due to nausea and vomiting(1), WCC >10 (2), or left shift (1) (eg raised neutrophils).  With a score of <4 , there is a 96% probability that it is not appendicitis.  In practice, it tends to be used when trying to prove why you do not think that someone’s RIF pain is appendicitis.  Some of the features within the Alvarado score may potentially come up as part of the background for an exam question so worthwhile knowing about them.


Other quirky and evidence backed signs include the road hump sign – pain when the car bringing the patient to the SAU is driven over a speed bump.  I like that one.


What investigations need to be run and why?

Bloods as explained above, but really you need a full set as you are also thinking potentially for theatre.  FBC, U&E, CRP, and G&S would likely be the minimum. 


It is worthwhile excluding other causes of RIF pain if possible, easier in men than women as there is less there. 


Urine dip - with appendicitis, you might find that an inflamed appendix will cause some raised leukocytes, but not nitrates.  Also pregnancy test. History will have to include last menstrual cycle in women of reproductive age.


If there is diagnostic uncertainty then an ultrasound scan is sometimes helpful, but the appendix cannot always be visualised adequately. 


CT scanning is very accurate and very reliable, but also a lot of radiation, and if it appears to be appendicitis, you are probably better to crack on and remove the appendix before it perforates, than to try and image away the appendicitis.


So you just operate on appendicitis?

Short answer yes, there are always exceptions to the rule but they are all a lot more post graduate.  Most appendicectomies are performed laparoscopically.  If the appendix is found at operation to be innocent and healthy in appearance, then it is still typically removed for histological confirmation, but the caecum and ileum are inspected, and the right ovary in girls.  Occasionally there is fluid within the pelvis, which can be inflammatory or perforation.  This is one of the benefits of laparoscopic surgery, the pelvis is washed out and drains placed.

26/03/19 Girly causes of Right Iliac Fossa (RIF) pain.


Why girly causes?

Basically women have more bits down there than the boys.  That said, the issues with the girls can potentially be a lot more dangerous and deteriorate very rapidly! 


Ectopic pregnancy. 

Identified early enough, you can massively reduce the morbidity and mortality associated with an ectopic pregnancy.  Ectopic pregnancies can be anywhere outside of the womb, but most are within the fallopian tubes, with <1% still on the ovary and <1% in the cervix.  When the ectopic outgrows it’s environment, it not only dies but causes bleeding, some may be vaginal and make a woman think that she has started her period, the rest could be into the abdomen.  This is why for all women you HAVE to do the pregnancy test.  I don’t care if she is a lesbian nun with a coil, dip that pee. 

Are any women particularly at risk for ectopic pregnancies?

Well there are some things that increase a woman’s likelihood of developing an ectopic, with previous ectopic being high on the list.  Beyond that, any tubal or pelvic surgery can increase the odds.  The odds of ectopic pregnancies increase in women who had suffered with pelvic inflammatory disease.  Smoking is an independent risk factor.  Last but not least we get onto the who baby making.  Women who had fertility issues or assisted conception unfortunately also have higher odds of having an ectopic pregnancy.  Women who think that they cannot be pregnant because they are on the Progesterone Only Pill for contraception, or an intrauterine device, or who took emergency contraception are probably right, as their odds of being pregnant in the first place are lower, but if they di turn out to be pregnant, the odds that this is an ectopic pregnancy are higher.

Can’t you just move the foetus to the proper place and save the baby?

I have been asked this by a woman who was in this situation, it truly is heart breaking and I wish that it were possible, but no, the foetus is not a viable pregnancy.  The rush comes to prevent as much damage to the woman as possible, so as to give her the best opportunity to try for another baby in the future. 

Are all ectopic pregnancies treated surgically?

No, some that are picked up in routine screening can even be treated by ‘expectant management’, as in the foetus will spontaneously abort.  Spontaneous abortion is the medical term for miscarriage, and can cause some confusion and upset, so be careful to explain these terms to patients when using!  There is also medical management via drug induced abortion. 

If you want to learn more about ectopic pregnancies, I found a useful resource in the writing of this section.


What other gynae causes of RIF pain?

Cyst rupture.  As part of the whole menstrual cycle, the ovary produces small cysts which rupture to release the ova or egg.  This is outside of the womb and fallopian tubes.  Sometimes, one of these cysts can grow really big, so when that ruptures, the poor woman gets a sudden onset severe abdominal pain from the fluid in the pelvis.  The pain resolves without too much intervention.


Ovarian torsion. It is a thing, and often associated with large cysts causing an abnormal ovary.


Retrograde menstruation.  Basically you can sometimes get some of the menstural blood come back through the fallopian tubes rather than down the cervix and out of the vagina.  I would tend to double check the pregnancy test with a blood hCG to confirm not an ectopic pregnancy, and/or USS of the pelvis which would on the finding of fluid in the abdomen, typically check the reproductive organs.


Pelvic Inflammatory Disease – PID, is the chronic inflammatory process in the pelvis and abdomen following an untreated infection with Chlamydia.  It mimics other conditions, and should not necessarily be a 1st diagnosis, unless there is a clear history, and even then you would probably want to check with imaging that it isn’t an appendicitis.


Displaced intrauterine device.  An IUD sounds to me like some kind of a bomb, but it isn’t.  There are basically 2 things that could get inserted into the cervix with contraceptive purposes, the copper coil which lasts ages, is really effective at preventing pregnancies because it doesn’t rely on remembering to take shots or medications, but can worsen heavy menstrual bleeding.  Then there is the IUD – a common make being the Mirena coil.  This is a bit of plastic in a T shape that slowly releases progesterone and is used for both contraception and also has the bonus of reducing menstrual bleeding, or even stopping it.  It should sit at the top of the neck of the cervix, and most do, but there’s always that one bugger that goes off and sticks itself somewhere altogether different.  They are quite pokey and you can actually perforate the uterus with it, but that would tend to show on abdominal XR.

03/04/19 Diverticular disease.


So what is diverticulosis, diverticular disease and diverticulitis?


The colon is a tube, made of muscles and tissue called mucosa.  Sometimes along this tube people develop outpouching or small bubbles along the length of the colon through the muscle layer.  These are diverticulosis, and if they start to cause you some issues then you are diagnosed with diverticular disease.  Now if these pouches get inflamed or infected (they are covered in faeces) then you develop diverticulitis.


Why do people get diverticulae?

Our poor Western diet is blamed for this, with the lack of fibre leading to chronic increased bowel pressures to propel food along the colon.  It is more common in older people but has been seen in younger individuals. 


What are the symptoms?

Simple diverticulosis can be asymptomatic and picked up incidentally. 

Diverticulitis can cause PR bleeding which can be serious, and infection. The patient complaining of abdominal pain, anything from pain and mild tenderness through to peritonitic abdomens and sepsis.  The typical exam question tends to be a nana with pain in the left iliac fossa (LIF) so as to differentiate from other causes of abdominal pain, because actually most of the time a nana presents unwell with pain and tenderness in the LIF it probably is diverticulitis. 

So can these pouches pop?

Short answer, yes. 

Longer answer, there is a whole classification system for how much of a problem this is, the Hinchey classification, which is a bit beyond the scope of undergraduate medicine, and some argue about subdividing the classifications. 

So what do you do with these patients?


Prioritise, depending on how sick the patient in front of you is.  Get a full history, as most diverticular patients are a bit older they tend to have some other co-morbidities.  Do a full appropriate examination. 


Well and no issues = dietary advice and red flag advice.


Bloods including venous blood gas (VBG), Full blood count (FBC), C Reactive Protein (CRP), Urea and electrolytes (U&Es).  Usually

you will end up including LFTs and Amylase if there is any doubt to the cause of abdominal pain, and it makes sense to get a group and save on admission of any potential surgical patients in preparation.  The lactate of the VBG is useful as a measure of sepsis and is a quick result.


Imaging, CT Abdomen and Pelvis – if not seriously unwell can wait for morning. At a minimum get a abdominal (AXR) and erect chest X ray (CXR), because while arguments still happen all the time about the value of an AXR, if you are not getting an immediate CT you will need to see if there are signs of obstruction on AXR which is the one thing that everyone agrees it is useful for, and you don’t want to miss.  The erect CXR is looking for air under the diaphragm which is a sign of perforation which will escalate your management.


Antibiotics based on local trust guidelines and patient allergies, usually IV, IV fluids based on electrolytes and the patient (don’t drown the nana’s with heart failure).  Bowel rest, nothing to eat.


Colonoscopy would be performed after the acute inflammation has resolved, usually around 6-8 weeks later.  Doing a colonoscopy while the bowel is inflamed would not only hurt more, but also increase the risk of perforating the bowel.


If you are presented with a patient who is very ill, signs of sepsis, raised lactate on VBG, distended hard abdomen, NEWS 4 or any of these things – get a senior review urgently, CT very soon, and if perforation is confirmed they may need theatre.  See the National Emergency Laparotomy Audit (NELA) guidelines.  While waiting for help to arrive, you need to get the other things on board so that they are optimised for whatever happens next.


My nana has diverticular disease, should I be worried?


If your nana has signs of being seriously unwell then yes, regardless of any history of diverticular disease.  Diverticular disease can usually be treated conservatively should the patient develop diverticulitis.  If she just has a few diverticulosis found incidentally then I don’t think you should be anymore worried than you were before reading this section.  Rapid surgery puts the number of people with diverticulosis who go on to suffer diverticulitis at 25%, with 30% of them having further episodes.




10/04/19 Renal Colic

Is that like kidney stones?

Kidney stones or calculi are depositions that form within the urinary tract, which are medically termed nephrolithiasis.  When a stone passes down from the kidney down the ureter towards the bladder, there are a number of places in which the ureter is slightly narrowed and the nephrolithiasis (I will just write stone from here forward), can get held up.  When the stone is stuck, the ureter spasms trying to progress it forwards and these intermittent spasms, contracting around the stone are painful.  We term the intermittent increased pain as colic.  Further pain comes from the capsular distension around the kidney from the back pressure.  So basically yes, kind of, Kidney stones cause renal colic.

So how do you get a kidney stone?

There is a process called supersaturation, in which the urine becomes over saturated with the waste chemicals and can form a crystal.  The most common type of stone is the calcium phosphate or calcium carbonate which fortunately show on imaging reasonably well.  Less common is the struvite (Magnesium, ammonium and phosphate) which are associated with bacteria which act on the urea, proteus being the one commonly mentioned in exams, but also pseudomonas and klebsiella.  The struvite stones are the ones that can form the ‘staghorn’ calculi within the renal pelvis.  Urate crystals form in the urine, in much the same way as they do in joints in gout, and the treatment is similar.  This is associated with acidic urine, which can also come from small bowel disease and cell lysis.  There are other rarer stone types, typically associated with metabolic disorders.

So why do some people get kidney stones?

Some people are really lucky like that!  Actually quite a lot of people, puts it at 3 in 20 men and 2 in 20 women developing them at some point.  Once again the Western diet is identified as a contributor for the more common causes of renal stones.  As a former Cola addict I can fully appreciate how nice it is to drink, and how easy it is to drink to excess, and fizzy drinks, especially cola, are associated with stones.  All things that leave someone slightly more dehydrated such as working in hot environments and not drinking enough water. There are less common causes such as hypercalcaemia secondary to other causes such as hyperparathyroidism.  Once you have had a stone, you increase your probability of developing another by 33-50% over the next 3 years (depending on your source).

So what are the symptoms of kidney stones?

That depends on the size of the stone.  Very small stones can pass completely asymptomatically as there is no obstruction, there is no colic. 

Patients can suffer symptoms of a urinary tract infection, and have a urinary tract infection, with frequency and urgency, or even retention.

Renal colic as described above is the pain felt with the renal stones, it can be very severe, with pain radiating from the back round to the front (loin to groin), and can radiate down into the genitalia.  Typically patients will have a background pain that episodically gets much worse before settling back to bad.  During the episodes, a patient will typically roll around with the pain, beware a patient who prefers to be still during an episode of pain, as they are more typical or peritonitis type pain.  One of the tightest constrictions of the ureter is just as it enters the bladder, so it is not unusual for the pain to peak when it is there, only for the back pressure to push the stone through. 

What are the investigations for renal colic?

Urine dip – in most cases there will be some blood, but not all.  If there is any sign of an infection, this will need sending for


Microscopy, Cultures and Sensitivity (MC&S), for appropriate management.


Bloods – FBC, U&E, CRP, Bone profile, Urate.  You want to know how the renal system is coping with the back pressure, and may be completely unaltered if the other kidney has taken over all of the requirements.  You want to know if there is systemic illness or infection, and look at the commoner causes of renal stones for future prevention.


CT of the urinary system – Kidney, ureters and bladder (CT KUB) is the most preferred, but you are unlikely to get this out of hours unless the patient either has deranged U&E’s showing severe kidney injury, in which a urologist would act overnight with a nephrostomy etc, or only 1 kidney. 


US KUB – similar to above but no radiation.  The benefit of the CT is it’s slightly better for treatment planning.

What do you do for renal colic?

For the acute presentation, fluids, analgesia – often in the form of NSAIDs unless contraindicated, if signs of an infection, will require more urgent attention and antibiotics.  If a kidney is obstructed, or there is infection behind it, then action is required by the urologist to relieve the pressure by way of a stent, which can either be placed by cystoscopy (camera in the bladder) and placing the stent up the affected ureter, bypassing the obstruction with the help of radio-opaque dye and X-ray to make sure that you are round, or by percutaneous nephrostomy, where you stick a tube through a hole that you make in the back into the kidney to drain it. 

Longer term treatment of stones, depends on the stone:

Small stones <5mm will usually pass with minimal difficulty, and patients are sometimes given medications to decrease ureteric spasm during this, such as alpha blockers. 

Larger stones 5mm – 20mm will need a bit of help getting out, either via ureteroscopy to visually identify the stone and try to grab it and pull it out, or Extracorporeal shockwave lithotripsy – where they essentially beat your back in a clever way to causes a shock wave to break up the stone into smaller fragments which may then pass. 

Even bigger stones >20mm, eg staghorn calculi, may require percutaneous nephrolithotomy. In these cases the kidney was obstructed, so a percutaneous nephrostomy tube is placed to relieve the obstruction.  Through this opening a scope can be passed and the stone broken up and removed.  The nephrostomy remains until ureteric drainage is confirmed.

If a kidney is non-functioning, it may be removed. 


What don’t you want to call renal colic?

Abdominal Aortic Aneurysm (AAA).  The odds of a patient presenting with bilateral renal stones are lower than those of them presenting with a previously undiagnosed AAA.  I don’t have numbers to support this, but always assume that bilateral renal colic is actually AAA until you have evidence in the form of CT scan that it is not. 


Renal cell carcinoma – may cause all of the above symptoms.  Just remember that renal colic will not make you anaemic or cause you weight loss, that is more likely to be cancer.


Appendicitis – they can mimic each other.



My dad had a kidney stone, am I more likely to get one?

Potentially there are some genetic causes and traits to increase the chances of you getting a kidney stone. Also, similar eating and drinking habits, may increase both of your risk.  Make sure that you have a good intake of water, especially when how, and hold off the fizzy pop a bit and you will likely be fine.


24/04/19 The National Emergency Laparotomy Audit (NELA).

What is NELA and why do we care?

So the National Emergency Laparotomy Audit (NELA) is a national audit involving all hospitals in England and Wales which provide emergency laparotomies.  I guess the clue was in the name really.  The point of the audit is to improve quality and outcomes with solid data for each hospital to raise the level of care throughout.  It also helps to quantify the probability of what might be considered bad outcomes based on a number of influencing factors, and helps in decision making processes. 


Obviously if you are the junior trying to book an emergency laparotomy you care, it is now a mandatory form to fill in, and it is a pain in the backside if you don’t have all the information you need ready.  For the rest of us, it is still useful to know and be able to quantify probability for really sick patients.  While you are unlikely to be asked a direct question about NELA on your exam, you may be asked questions which require an understanding of the process.


So when do you use NELA?

Again, the clue is in the name.  When ever you have a patient who requires an emergency laparotomy.  By requires it includes people who then for whichever reason do not go on to have the surgery.  While NELA is an audit it also comes with guidance regarding how to deal with acute surgical patients.  In reviewing acutely unwell surgical patients from admission it offers advice and guidelines for all involved from attendance at A&E to consultant review.  It helps with requesting CT scans etc.

When you find that you have an acutely unwell surgical patient you fill in the NELA audit calculator which produces a couple of scores which calculate morbidity and mortality.  These are used in gaining valid consent from the patient. 

Many theatres now in England and Wales will not allow you to book a case into emergency theatre without completing the scoring first.  There are a number of pathway examples on the NELA website


What do you need for NELA?



American Society of Anaesthesiology (ASA) grade

Observations (Blood pressures, Heart rate, GCS)


Chest XR and CT results.

History especially that of Shortness of Breath, surgical history including how many operations in the last 30 days.  Also any known or anticipated malignancy.

The anticipated surgery urgency, severity and blood loss.   Also the anticipated peritoneal soiling.

Bloods (urea and electrolytes, full blood count) but generally speaking you should also have clotting and group and save as well.



What does this mean?

So for someone like me, young, with healthy bloods and obs, if I was to have a major surgery with minimal peritoneal soiling and minimal blood loss the Estimated mortality is 0.3%, and estimated morbidity 15.3%. 

If however I was having super urgent surgery with higher estimated blood loss and faecal soiling then while my mortality would only increase to 0.7% but my estimated morbidity would jump up to 92.2%. 


A nana in the same situation has a mortality of 10% for major urgent surgery, and 5.5% for the lesser surgery.   Add into that, the increased probability that nana has maybe a bit of Atrial fibrillation, an acute kidney injury and is now ragingly septic with low BP, high WCC.  Even if she walks 14 miles every Sunday, her estimated mortality is 13.7% and estimated morbidity of 95.6%. 



OK, great, but what does Morbidity actually mean? (I get the mortality thing).

Morbidity is basically a state of being anything between fine and dead.  There is quite the continuum really and you can appreciate why someone with faecal soiling is more likely to have some issues than someone with a clean abdomen. 


From a patient perspective this is sometimes more important that mortality.  I had 1 patient who was had acute obstruction and refused surgery unless the operating surgeon agreed to not give her a colostomy, and expressed that she would not consent to that and would sooner die.  Having some predictive tools to assist with this conversation can be useful. 


Where do I go to learn more?

The NELA website has a number of links and is funded until December 2020

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