General Surgery in the GI Tract Flashcards
What is the general approach to a patient presenting with acute abdominal pain?
PC = use SOCRATES for pain assessment
[Site, Onset, Character, Radiation, Association, Time course, Exacerbating/Relieving factors, Severity / Scale)
PMHx, DHx, SHx
Investigations
Management
What are some investigations that could be performed for acute abdominal pain?
Investigations ordered depend on the presentation
Bloods: VBG, FBC, CRP, U&Es (urea and electrolytes - renal profile), LFTs + amylase
Urinalysis + Urine MC&S - always do these, many acute abdominal issues come from UTIs
Imaging:
Erect CXR, AXR, CTAP (CT abdo and pelvis), CT angiogram (suspected bleeding or infarction of intraabdominal blood vessel), USS
Endoscopy
What are the management approaches for acute abdominal pain?
ABCDE approach - airways, breathing, circulation, disability, exposure
Conservative management
Surgical management
What are the differentials for RUQ / right hypochondriac pain?
Bilary Colic Cholecystitis/Cholangitis Duodenal Ulcer Liver abscess Portal vein thrombosis Acute hepatitis Nephrolithiasis RLL pneumonia
List not exhaustive
What are the differentials for epigastric pain?
Acute gastritis/GORD Gastroparesis Peptic ulcer disease/perforation Acute pancreatitis Mesenteric ischaemia AAA (Abdominal Aortic Aneurysm) Aortic dissection Myocardial infarction
List not exhaustive
What are the differentials for LUQ / left hypochondriac pain?
Peptic ulcer Acute pancreatitis Splenic abscess Splenic infarction Nephrolithiasis Left Lower Lobe Pneumonia
List not exhaustive
What are the differentials for RLQ / right iliac pain?
Acute Appendicitis Colitis IBD Infectious colitis Ureteric stone/Pyelonephritis PID/Ovarian torsion Ectopic pregnancy Malignancy
List not exhaustive
What are the differentials for suprapubic / central pain?
Early appendicitis Mesenteric ischaemia Bowel obstruction Bowel perforation Constipation Gastroenteritis UTI/Urinary retention PID - pelvic inflammatory disease
List not exhaustive
What are the differentials for LLQ / left iliac pain?
Diverticulitis Colitis IBD (Inflammatory Bowel Disease) Infectious colitis Ureteric stone/Pyelonephritis PID/Ovarian torsion Ectopic pregnancy Malignancy
List not exhaustive
How do patients with bowel ischaemia present clinically?
Sudden onset crampy abdominal pain
Severity of pain depends on the length and thickness of colon affected (positive correlation)
Bloody, loose stool (currant jelly stools)
Associated fever, signs of septic shock
What are the risk factors for bowel ischaemia?
Age >65 yrs Cardiac arrythmias (mainly AF) and history of atherosclerosis Hypercoagulation/thrombophilia Vasculitis Sickle cell disease Profound shock causing hypotension
What are the 2 types of bowel ischaemia?
- Acute mesenteric ischaemia
2, Ischaemic collitis
What are the main features of acute mesenteric ischaemia?
Small Bowel
Usually occlusive and secondary due to thromboemboli (SMA) - AF (atrial fibrillation) makes this more likely as cardiac arrythmia can throw small clots to block the SMA
Sudden onest (but presentation and severity varies)
Abdominal pain can be out of proportion of clinical signs
e.g. extreme pain but nothing clinically wrong OR something major clinically but patient feels well
What happens if the clot completely occludes / obstructs the SMA?
Lose all the bowel from the DJ (duodenojejunal) flexure to the splenic flexure - all the small bowel + 3/4 of large bowel
What are the main features of ischaemic Collitis?
Large bowel
Usually due to non-occlusive low flow states or atherosclerosis
More mild and gradual (80-85% of cases)
Moderate pain and tenderness
What investigations should be performed for suspected bowel ischaemia?
Bloods =
FBC: neutrophilic leukocytosis (abnormally high number of neutrophils)
VBG (venous blood gases): Lactic acidosis (low pH from build up of lactic acid due to late stage mesenteric ischaemia = dead bowel)
Imagings =
CTAP/CT Angiogram:
Detects - disrupted flow, vascular stenosis, ‘Pneumatosis intestinalis’ (transmural ischaemia/infarction), and Ischaemic colitis: Thumbprint sign (unspecific sign of colitis)
Endoscopy =
For mild or moderate cases of ischaemic colitis (detects oedema, cyanosis, ulceration of mucosa)
What is the conservative management approach to an ischaemic bowel and when is it used?
Suitable only for mild to moderate cases of ischaemic collitis (not suitable for small bowel ischaemia)
IV fluid resuscitation
Bowel rest - nil by mouth
Broad-spectrum antibiotics - as colonic ischaemia can result in bacterial translocation and subsequent sepsis
NG tube for decompression - in concurrent ileus
Anticoagulation
Treat/manage underlying cause
Serial abdominal examination and repeat imaging - check for changes(e.g. perotonitis inside the abdomen) / progress of treatment
When is surgical management used for ischaemic bowel?
Almost a necessity in most patients
Required in: Small bowel ischaemia Signs of peritonitis or sepsis Haemodynamic instability Massive bleeding Fulminant colitis with toxic megacolon
What are the two types of surgical management?
Exploratory laparotomy =
Explore everything from the DJ flexure to the rectum
Resect necrotic bowel with or without open surgical embolectomy (baloon catheter in SMA) or mesenteric arterial bypass
Endovascular revascularisation =
Balloon angioplasty/thrombectomy
In patients without signs of ischaemia
How does acute appendicitis present clinically?
Initially periumbilical pain that migrates to RLQ (within 24hours)
Usually associated with anorexia, nausea +/- vomiting, low grade fever, change in bowel habit (due to inflamed appendix located next to the rectum, irrtating it, hence altering the bowel habit)
Good way to test for anorexia - ask to get them a meal, if they refuse, likely to be appendicitis
What are the important clinical signs in acute appendicitis?
McBurney’s point = usually where the appendix lies (lateral 1/3 of a hypothetical line drawn from the right ASIS to the umbilicus), tenderness in the RLQ
Blumberg sign = rebound tenderness especially in the RIF (right iliac fossa) - press down and suddenly release = patient suddenly jump
Rovsing sign = RLQ pain elicited on deep palpation of the LLQ - press down on the left iliac fossa but they report pain in the right iliac fossa due to moving of the perotineum causing irritation on the other side
Psoas sign = RLQ pain elicited on flexion of right hip against resistance
Obturator sign = RLQ pain on passive internal rotation of the hip with hip & knee flexion
What investigations should be carried out for suspected acute appendicitis?
Bloods =
FBC: neutrophilic leukocytosis
Increased CRP
Urinalysis: possible mild pyuria / haematuria
Electrolyte imbalances in profound vomiting
Imaging =
CT: gold standard in adults esp. if age > 50
USS: children/pregnancy/breastfeeding
MRI: in pregnancy if USS inconclusive
Diagnostic laparotomy = only used in persistent pain and inconclusive imaging
What is the diagnostic tool used for acute appendicits?
Alvardo score = consists of 6 clinical items:
(brackets represent points awarded for each sign)
RLQ Tendereness (2) Fever (1) Rebound tenderness (1) Pain migration (1) Anorexia (1) Nausea +/- vomiting (1) WCC > 10,000 (2) Neutrophilia (left shift) (1)
≤4 Unlikely
5-6 Possible
≥7 Likely
What is the conservative management for acute appendicitis?
When do you use conservative management?
Conservative Management =
IV Fluids, Analgesia, IV or PO Antibiotics
In abscess, phlegmon or sealed perforation - resuscitation + IV antibiotics +/- percutaneous drainage
Only used when =
After negative imaging in selected patients with clinically uncomplicated appendicitis
Usually when patient presents late with mass/abscess/phlegmon formation in their RIF (right iliac fossa) = CT-guided drainage and IV antibiotics as surgery to now take appendix out is a major undertaking so it is far better to treat conservatively
What is an interval appendicectomy and why is it used after conservative management of acute appendicitis?
Take out appendix electively on a scheduled date
Although late presentations are treated conservatively initially due to risk of surgery complications
After consevative management, most patients are later revisted with an interval appendicectomy as rate of recurrence after conservative management of abscess/perforation is 12-24%, so appendix is taken out later electively before it causes further issues
What are the benefits of laparoscopic over open appendicectomy ?
Less pain Lower incidence of surgical site infection Decreased length of hospital stay Earlier return to work Overall costs Better quality of life scores
Most patients are home the next day = quick recovery time
What are the steps of laparoscopic appendicectomy?
Trocar placement (usually at 3 port sites)
Exploration of RIF & identification of appendix
Elevation of appendix + division of mesoappendix (containing artery)
Based secured with endoloops and appendix is divided - so first you mobilise the appendix, then you lasso around the base and tighten
Retrieval of appendix with a plastic retrieval bag - to avoid infection spreading in the abdo cavity and port site
Careful inspection of the rest of the pelvic organs/intestines
Pelvic irrigation (lavage / wash out) + Haemostasis
Removal of trocars + wound closure
What is bowel / intestinal obstruction?
Restriction of normal passage of intestinal contents
What are the 2 main groups of intestinal obstruction?
- Paralytic (adynamic) ileus - occurs when the abdomen is full of pus that irritates the bowel, the bowel stops peristalsis and this does not get better until the infection is gone
- Mechanical - a physical obstruction causing fluids and waste to build up in the portion of the bowel prior to the obstruction
What are the 4 components to classifying a mechanical intestinal obstruction?
- Speed of onset
- Site
- Nature
- Aetiology
What of each of the components below highlight about the mechanical intestinal obstruction?
- Speed of onset
- Site
- Nature
- Aetiology
- Speed of onset = acute, chronic or acute-on-chronic
- Site = high or low
- Roughly synonymous with small or large bowel obstruction - Nature = simple VS strangulation
- Simple = bowel occulded without damage to blood supply (bowel still perfused and healthy)
- Strangulation = blood supply of involved segment of intestine is cut off (e.g. in strangulated hernia, volvulus, intussusception - e.g. a polyp that is taken down by peristalsis causing the bowel to turn inside out like the sleeve of a jacket) - Aetiology =
- Causes in the lumen = faecal implantation, gallstone ‘ileus’ (gallstone erodes through the gallbladder into the bowel)
- Causes in the wall = Crohn’s disease, tumours, diverticulitis of colon
- Causes outside the wall - strangulated hernia (external or internal), volvulus, obstruction due to adhesions or bands
What are the main causes of small bowel obstruction?
Adhesions (60%) - patient usually has PMH of previous abdominal surgery
Neoplasia (20%) - primary (rare), metastatic or extraintestinal e.g. can happen in ovarian peritoneal disease with peritoneal deposited tumour can catch a part of the small bowel
Incarcerated hernia (10%) - external (Within abdominal wall) or internal (mesenteric defect)
Crohn’s disease (5%) - acute (oedema) or chronic (strictures)
Other (5%) - intussusception, intraluminal (foreign body, bezoar)
What are the main causes of large bowel obstruction?
Colorectal cancer - usually occurs on left hand side to cause obstruction as on the right hand side a small tumour can be compensated by bowel expansion and so will require a significantly larger tumour
Volvulus - twist of the bowel on itself like a balloon at the sigmoid or caecal part of the colon
Diverticulitis - inflammation, strictures
Faecal impaction -
Hirchsprung disease - birth defect and commonly presents in infants / children, characterised by absence of nerve cells / ganglions in a sengment of the bowel, so that part of the bowel cannot carry out peristalsis leading to long term obstruction
What are the 4 main signs of a patient presenting with a bowel obstruction?
Abdominal pain
Vomiting
Abdolute constipation
Abdominal Distension
How do patients present clinically with small bowel obstruction?
Abdominal pain = colicky, central pain
Vomiting = early onset vomiting (i.e. the higher up the obstruction, the wuicker the vomiting starts due to fluid build up) - large amount and bilious
Absolute constipation = late sign, as everything in the large bowel can still come through
Abdominal distention = less significant
How do patients present clinically with large bowel / colon obstruction?
Abdominal pain = colicky or constant pain
Vomiting = late onset - the back pressure needs to travel up most of the GI tract to initiate comiting - initally billous progress to faecal vomiting (i.e. what they’re vomiting looks a lot like faeces
Absolute constipation = early sign
Abdominal distention = early sign and significant
What are some other signs patients with any type of bowel obstruction present with clinically?
Other signs =
Dehydration - from the vomiting
Increased high pitched tinkling bowel sounds (early sign), or absent bowel sounds (late sign due to stopping of peristalsis)
Diffuse abdominal tenderness - intervene asap
What are the three important factors for diagonisisng bowel obstruction?
Diagnosed by the presence of symptoms
Examination should always include a search for hernias and abdominal scars (looking for strangulated bowel), including laparoscopic portholes
Is it simple (viable bowel) or strangulating (non-viable bowel = faster intervention required)?
What features suggest it is a strangulation rather than a simple obstruction?
Change in character of pain from colicky to continuous
Tachycardia
Pyrexia
Peritonism - localised inflammation of the peritoneum
Bowel sounds absent or reduced
Leucocytosis
Increased C-reactive protein
What is the mortality rate of strangulating obstruction with peristonitis?
Up to 15%
What are common hernial sites?
Epigastric
Umbilical
Incscional - from previous operation, skin has healed but muscle below has a defect so bowel can come through that
Inguinal - at the groin, usually defects in the abdominal wall
Femoral
What is most important about the defect causing the hernia?
Size
Large defect = bowel can go in and out without any problems
The smaller the hole, the greater the chance of the hernia obstructing and strangulating
What are the 3 different types of hernia?
Neck of sac
Strangulated hernia = compromised blood flow, venous return is first to go, so as blood stops going out, it compresses the arterial blood coming in leading to ischaemic bowel
Richter’s hernia = just a small amount of bowel caught, so there is still continuity of the small and large bowel but there is that small portion of ischaemic bowel that needs to be removed
What are the investigations that can be carried out for a suspected bowel obstruction?
Bloods =
WCC/CRP = usually normal (if raised suspicion of strangulation / perforation)
U&E = electrolyte imbalance from vomiting
VBG (venous blood gas) from vomiting shows HypoCl- (hypochloraemic), HypoK+ (hypokalaemia) = metabolic alkalosis
VBG if strangulation = metabolic acidosis (lactate)
Imaging =
Erect CXR / AXR (chest / abdominal x-ray)
- SBO (small bowel obstruction) = Dilated small bowel loops >3cm proximal to the obstruction (central)
- LBO (large bowel obstruction) = dilated large bowel >6cm (if caecum >9cm) predominantly peripheral
CT abdo/pelvis = shows transition point (helpful for surgery), dilatation of proximal loops – IV or oral contrast if possible
What does a small bowel obstruction on an abdominal x-ray show?
Ladder pattern of dilated loops & their central position (easier to see on supine than erect xray)
Striations that pass completely across the width of the distended loop produced by the circular mucosal folds
What does a large bowel obstruction on an abdominal x-ray show?
Distended large bowel tends to lie peripherally (easier seen on erect xray)
Show haustrations of taenia coli - do not extend across whole width of the bowel.
What information can CT scans show regarding bowel obstructions?
Can localize site of obstruction
Detect obstructing lesions & colonic tumours
May diagnose unusual hernias (e.g. obturator hernias).
What are the 3 types of management for a bowel obstruction?
Supportive
Conservative
Surgical
What is the supportive mangement for bowel obstruction?
NBM (nil by mouth), IV peripheral access with large bore cannula - IV Fluid resuscitation (basic rate depends on weight)
IV analgesia (For colicky pain), IV antiemetics, correction of electrolyte imbalances
NG tube for decompression (vital for removing chance of aspiration pneumonia), urinary catheter for monitoring output (influences IV fluid replacement)
Introduce gradual food intake if abdominal pain and distension improve
What do you need to be careful of for small bowel obstruction with the commonest cause is secondary to adhesions?
The more fluid you pump into it, the more it twists on that area = worsening of obstruction
What is the conservative treatment for bowel obstruction?
Faecal impaction = stool evacuation (manual, enemas, endoscopic)
Sigmoid volvulus: rigid sigmoidoscopic decompression - pass tube through bowel and suck all the fluid out causing it collapse, giving it a chance to straighten it out
SBO: oral gastrograffin (highly osmolar iodinated contrast agent) can be used to resolve adhesional small bowel obstruction
When is surgical management used, and what are the indications of surgical management for bowel obstruction?
Used when bowel obstruction does not resolve OR patient has developed signs of ischaemia
Haemodynamic instability or signs of sepsis
Complete bowel obstruction with signs of ischaemia
Closed loop obstruction - intervene quicly before it becomes ischaemic e.g. strangulated hernia
Persistent bowel obstruction >2 days despite conservative management
What are the surgical management operation options available?
Exploratory Laparotomy / Laparoscopy - find the cause and remove it, ensure all bowel left is viable
Restoration of intestinal transit (depending on intra-operational findings)
Bowel resection with primary anastomosis or temporary/permanent stoma formation (when it is not safe to join the 2 ends of the bowel straight away after the resection of the non-viable bowel)
What is endoscopic stenting and when is it used?
Non-surgical management of distal obstruction - stend placed endoscopically to prevent constriction or collapse of tubular organ
Reserved for patients with tumours
How does GI perforations present clinically?
Sudden onset severe abdominal pain associated with distention
Examination shows diffuse abdominal guarding, rigidity, rebound tenderness
Pain aggravated by movement
Nausea, vomiting, absolute constipation (due to ileus i.e. irritation of chemicals of the bowel rather than mechanical obstrution)
Fever, Tachycardia, Tachypnoea, Hypotension
Decreased or absent bowel sounds
What are the 4 main perforations of the GI tract?
Perforated peptic ulcer
Perforated diverticulum
Perforated appendix
Perforated malignancy
What are the features of perforated peptic ulcer?
Sudden epigastric or diffuse pain
Referred shoulder pain - diaphragm irritation - as phrenic nerve innervates shoulder
HPC / PMH of NSAIDs, steroids, recurrent epigastric pain
What are the features of perforated diverticulum?
LLQ pain
Constipation
What are the features of perforated appendix?
Present a phlemons (inflammation of soft tissue under skin)
Migratory pain
Anorexia
Gradual worsening RLQ pain
What are the features of perforated malignancy?
HPC of: Change in bowel habit Weight loss Anorexia PR Bleeding
What are the investigations carried out for a suspected GI perforation?
Bloods =
FBC = neutrophil leukocytosis
Possible elevation of urea and creatinine (checking renal function)
VBG (venous blood gas) = lactic acidosis
Imaging =
Erect CXR =
- Subdiaphragmatic free air (pneumoperitoneum)
CT abdo/pelvis
- Pneumoperitoneum, free GI content, localised mesenteric fat stranding
can exclude common differential diagnoses such as pancreatitis
What other conditions can present as a GI perforation (i.e. what else would be on your differential diagnoses?)
Acute cholecystitis
Appendicits
MI
Acute pancreatitis
What is the supportive / conservative management given to the patient on presentation of a suspected GI perforation?
NBM & NG tube IV peripheral access with large bore cannula - IV Fluid resuscitation Broad spectrum antibiotics IV PPI Parenteral analgesia & antiemetics Urinary catheter
What is the conservative management for GI perforation presentation without sepsis?
Conservative management in localised peritonitis without signs of sepsis = very rare
IR - guided drainage of intra-abdominal collection
Serial abdominal examination and abdominal imaging for assessment - look for any changes, and do not hestitate to shift management to surgical
But most people require an operation
What are the stages of surgical management for GI Perforation with generalised perotonitis with/without signs of sepsis?
Exploratory laparotomy/laparascopy
Primary closure of perforation with or without omental patch (most common in perforated peptic ulcer)
Resection of the perforated segment (e.g. in a perforated diverticulum) of the bowel with primary anastomosis or temporary stoma
Obtain intra-abdominal fluid for MC&S (microscopy culture and sensitivity), peritoneal lavage
If perforated appendix: Lap or open appendicectomy
If malignancy: intraoperative biopsies if possible
What are some common biliary and pancreatic causes of an acute abdomen?
Biliary Colic
Acute Cholecystitis
Acute Cholangitis
Pancreatitis
What are the symptoms, investigations and management options for biliary colic?
Symptoms =
Postprandial RUQ pain with radiation to the shoulder.
Nausea
Investigations =
Normal blood results
USS: cholelithiasis (often people already know they have gallstones)
Management =
Analgesia, Antiemetics, Spasmolytics
Follow up for elective cholecystectomy
What are the symptoms, investigations and management options for acute cholecystitis?
Symptoms =
Acute, severe RUQ pain
Fever
Murphy’s sign
Investigations =
Elevated WCC/CRP
USS: thickened gallbladder wall
Management =
Fluids, ABx, Analgesia, Blood cultures
Early (<72 hours) or elective cholecystectomy (4-6 weeks)
What are the symptoms, investigations and management options for acute cholangitis?
Symptoms =
Charcot’s triad: jaundice, RUQ pain, fever
Investigations =
Elevated LFTs, WCC, CRP, Blood MCS (+ve)
USS: bilary dilatation
Management =
Fluids, IV antibiotics, Analgesia
ERCP (within 72hrs) for clearance of bile duct or stenting
What are the symptoms, investigations and management options for pancreatitis?
Symptoms =
Severe epigastric pain radiating to the back
Nausea +/- vomiting
Hx of gallstones or EtOH use
Investigations =
Raised amylase/lipase
High WCC/Low Ca2+
CT and US to assess for complications/cause - only useful after a few weeks when there are changes
Management = Admission score (Glasgow-Imrie) Aggressive fluid resuscitation, O2 Analgesia, Antiemetics ITU/HDU involvement
