General - Large bowel Flashcards
1
Q
Give some of the risk factors for developing acute appendicitis?
A
- Family History
- Ethnicity - More common in caucasians but ethnic minorities at higher risk of perforation
- Environmental - seasonal presentation during summer
2
Q
Name 2 specific signs for acute appendicitis
A
- Rosving’s sign: RIF pain when palpating the LIF
- Psoas signs: RIF pain with extension of the right hip
3
Q
What imaging should be done for suspicion of acute appendicitis?
A
- CT scan is best type of imaging
- USS can be done but only works well in children or slim adults
- Can help rule of gynaecological pathology if this is a differential
4
Q
How is acute appendicitis managed?
A
- Definitive treatment is laparascopic appendicetomy
- Can try on antibiotics to see if settles but studies show best to remove the appendix
5
Q
What is the best way to manage a appendicular mass?
A
- In this case surgery does more harm than good
- Pt needs prologned antibiotic therapy (augmentin/co-amoxicav) and then offered surgery to remove appendix at a later date
6
Q
What are some of the complications of acute appendiciits?
A
- Perforation - if left untreated, can cause peritoneal contamination
- Surgical site infection
- Appendix mass - where omentum and small bowel adhere to the appendix
- Pelvic abscess - presents with feveer and a palpable RIF mass
7
Q
What is the most commonly used scoring system for acute appendicitis?
A
The Alvarado score
Score 1-4 dischage
Score 5-6 admit for observation/ admission
Score 7-10 surgery
8
Q
Describe the pathophysiology behind diverticular disease
A
- Aging bowel naturaly weakens over time
- Stool movements increase lumenal pressure and can cause outpouchings of mucosa through weaker areas of bowel wall
- Bacteria can grow in the outputchings leading to inflammation, potentially perforation
9
Q
What are some of the complications of someone with chronic diverticular disease?
A
Chronic disease can cause fistulae to form
Most commonly colovesical or colovaginal
10
Q
Give some risk factors for developing diverticular disease
A
- Increasing age
- Low dietary fibre
- Obesity
- Smoking
- Family history
- NSAID use
11
Q
What are the 4 different manifestations of diverticular disease?
A
- Diverticulosis - presence of diverticula (can be asymptomatic and incidental finding)
- Diverticular disease - when symptoms start to arise from diverticula
- Diverticulitis - inflammation of diverticula
- Diverticular bleed - when diverticula erode into a blood vessel - causes a large volume but painless bleed
12
Q
How does acute diverticulitis present?
A
- acute abdominal pain - typically sharp and localised to LIF, worse on movement
- Decreased appetite
- Pyrexia
- N+V
- Change in bowel habit
- Bleeding
13
Q
What investigations should be done if suspecting acute diverticulitis?
A
- Routine bloods: FBS, CRP, U+E, consider faecal calprotectin if diagnosis less clear
- Group and Save
- Venous blood gas
- Urine dipstick to exclude urological causes
- CT abdomen pelvis - best imaging
-
Flexible sigmoidoscopy suitable if diverticular disease is uncomplicated
- CT colonography is the alternative if patient not suitable
14
Q
What CT findings may suggest diverticulitis?
A
- Thickening of the colonic wall
- Pericolonic fat stranding
- Abscesses
- Localise air bubbles
- Or free air
15
Q
What staging is used for classifying acute diverticulitis based on CT findings?
A
Hinchey Classification
16
Q
How should patients with uncomplicated diverticular disease be managed?
A
- Manage as outpatient with simple analgesia and encourage oral intake
- Encourage high fibre diet
-
Outpatient colonsocopy arranged to exclude any masked malignancies
*
17
Q
How should patients with acute diverticulitis be managed?
A
- First conservatively: antibiotics, IV fluids, analgesia, encourage oral intake
- Symtpoms typically improve within 2-3 days
- If pt clinically deteriorates then repeat imaging
18
Q
When is surgical intervention for acute diverticulitis required?
A
Only if there is perforation with faecal peritonitis or overwhelming sepsis
19
Q
What procedure is performed in perforated cases of acute diverticulitis?
A
Hartmann’s procedure
Sigmoid colectomy with formation of an end colostomy
(Reversal of colostomy can be done at a later date but only in 50% of cases)
20
Q
What are some of the complications of acute diverticulitis?
A
- Recurrence (10-35%)
- Stricture (have to do a biopsy to check it’s not a malignant stricture)
- Obstruction
- Fistula formation
- Perforation
- Bleed
21
Q
What is a fistula?
A
An abnormal connection between 2 epithelial surfaces
22
Q
What is a sinus?
A
An open ended cavity
23
Q
What is Crohn’s Disease?
A
An inflammatory bowel disease affecting anywhere from mouth to anus but commonly tarets the distal ileum and proximal colon
24
Q
Describe the features of inflammation in Crohn’s disease
A
- Transmural (affects full thickness of bowel wall)
- Cobblestone appearance of deep ulcers and fistulas
- Skip lesions (non-continuous)
- Perianal disease
25
What microscopic features are seen in Crohn's disease?
Non- Caseating granulomas
26
What types of fistulas can form in Crohn's disease?
* Perianal
* Entero-enteric
* Recto-vaginal
* Entero-vesicular
* Entero-cutaneous
27
What are some of the risk factors for developing Crohn's disease?
* Family history (20% have 1st degree affected relative)
* Smoking
* White European
* Appendectomy
* increases risk directly after surgery
28
What are some of the extra-intestinal features seen in Crohn's disease?
* **MSK** - arthritis
* **Skin**- eythema nodosum, pyoderma gangrenous
* **Eyes-** uveitis, episcleritis, iritis
* **HBP** - primary sclerosing cholangitis, cholangiocarcinoma, gall stones
* **Renal** - stones
29
How does Crohn's disease present clinically?
* Bimodal ages: 15-30 and 60-80
* Episodic abdominal pain and diarrhoea
* May contain mucus and blood in stool
* Low grade Fever
* Malaise
* Anorexia
* Oral aphthous ulcers
* Perianal disease
30
What investigations should you do if suspecting Crohn's disease?
* **Routine bloods**: for anemia, low albumin (secondary to malabsorption), evidence of inflammation in CRP/WCC
* **Fecal calprotectin** - good sensitivity
* **Abdominal X-ray** to exlude any features of toxic megacolon
* **Stool sample** for any possible infective causes
* **Colonoscopy with biopsy**: *_Gold Standard_*
* **CT abdo pelvis** for sever chrohn's disease
* can demonstrate bowel obstruction, fistula formation, perforation, collection formation
* **MRI** if looking for enteric fistulae
31
Which drugs should be avoided in Crohn's disease patients and why?
Any **anti-motility** drugs e.g. loperamide
Why? Can induce **toxic megacolon**
32
How should acute attacks of Crohn's be managed?
* Fluids
* Nutritional support
* Prohphylactic heparin
* IBD flares cause pro-thrombotic state
* Medications
* **corticosteroids**
* **immunosuppresives** - azothioprine, mesalazine
* **biologics**- inflximab can be trialled as rescue therapy
33
How often is surgery needed for Crohn's disease patients?
What types of surgery are done?
70-80% will need surgery at some point in their lives
* Ileocaecal resection
* Surgery for peri-anal disease
* abscess draining, senton insertion, laying open of fistula
* Stricturoplasty
* division of strictures causing bowel obstruction
* Small or large bowel resections
34
What are some of **GI** complications of Crohn's disease?
* Fistulae
* Stricture formation
* Recurrent peri-anal abscess
* GI malignancy (3% chance of colorectal cancer, x30 more likely to develop small bowel CA)
35
What are some of the extra-intestinal complications of Crohn's?
* **Malabsorption**
* **Osteoporosis**
* secondary to malabsorption or long term steroid use
* **Increased risk of gallstones** (reduced absorption of bile salts at terminal ileum)
* **Increased risk of renal stones**
36
What are the typical demographics of patients with UC?
* Caucasian
* Bimodal distribution: 15-25yrs, 55-65yrs
* Males and Females affected equally
37
Describe the pattern of inflammtion seen in UC
* Diffuse continual inflammation of mucosa starting at the **rectum** and spreading **proximally** (potentially affecting the entire large bowel
* Histologically shows inflammation of the **mucosa and submucosa**
* **Pseudopolyps** can form from repeated episodes of ulceration and healing
38
What microscopic changes are seen in UC?
* Crypt abscesses
* Reduced goblet cells
* Non-granulomatous inflammation
39
What is meant by the term **backwash ileitis?**
* Seen in UC
* If the ileoceacal valve is incompetent a portion of the distal ileum
40
How does UC typically present?
* Blood diarrhoea (90% of cases)
* Increased frequency and urgency of defecation
* Tenesmus
* PR bleeding
* Mucus discharge
* May be clinically dehydrated +/- electroylyte imbalance if more widespread colonic involvement
* Malaise
* Anorexia
* Low grade fever
41
Which criteria is used to classify the severity of an UC exacerbation
**Truelove & Witts criteria**
42
What extra-intestinal complications can be seen in UC?
* **MSK** - enteropathic arthritis (typically affects nail joints), nail clubbing
* **Skin** - erythema nodosum
* **Eyes** - episcleritis, anterior uveitis, iritis
* **Hepatobiliary** - primary sclerosing cholangitis
43
Which investigations should be done for investigating UC?
* **Routine bloods**: FBC, U&Es, CRP, LFTs, clotting
* **Faecal Calprotectin** - raised in IBD but normal in IBS
* **Stool sample** - for microscopy and culture
* **Colonoscopy with biopsy** - for definitive diagnosis - flexi sig may be sufficient
* **avoid** in acute severe exacerbations
* **Abdominal Xray or CT scan** in acute flares to assess for toxic megacolon/ bowel perforation
44
What features may you find on an X-ray of a patient with UC?
* Mural thickening
* Lead pipe colon / loss of haustra (with barium studies)
45
How are flares of UC managed medically?
* Corticosteroid therapy and immunosuppresive agents (mesalazine or azothioprine)
* Add infliximab as rescue therapy if no response to the above
46
What are the indications for surgery in patients with UC?
* Disease non responsive to medical management
* Toxic megacolon
* Bowel perforation
* To reduce risk of colonic carcinoma if dysplastic cells detected on routine monitoring
47
Which surgical procedures can be done for patients with UC?
* **Total proctocolectomy**- curative, patient requires ileostomy
* Many patients first undego a **subtotal colectomy** which preserves the rectum
48
What complications can occur in UC?
* Toxic megacolon
* Colorectal carcinoma
* Osteoporosis
* Pouchitis - inflammation of ileal pouch
* symptoms: abdo pain, bloody diarrhoea, nausea
* treated with metronidazole and ciprofloxacin
49
What is toxic megacolon?
How does it present?
An acute form of colonic distension
Severe abdominal pain, abdominal pain, abdominal distension, pyrexia and systemic toxicity
50
How should toxic megacolon be managed?
Decompression of the bowel ASAP due to high risk of perforation
51
What is a volvulus
The twisting of a loop of intestine around its **mesenteric attachment** causing **closed loop opstruction**
Affected bowel can become **ischemic** leading to bowel **necrosis** and **perforation**
52
Where do volvuli most common occur and why?
At the **sigmoid colon** due to the **long mesentry** which increases with age makes it more prone to twisting
(can also occur at the caceum, stomach, small intestine and transverse colon)
53
Give some of the risk factors for developing a volvulus
* Increasing age
* Neuropsychiatric disorders
* Resident in nursing home
* Chronic constipation or laxative use
* Previous abdominal operations
* Male
54
How do patients with a volvulus present clinically?
Clinical features of bowel obstruction:
* colicky pain
* abdominal distension
* absolute constipation
* usually rapid onset
* vomiting occurs as a late sign (due to sigmoid being distal in GI tract)
* O/E: abdomen is often **tympanic to percussion**
55
Which investigations should be done if suspecting volvulus?
* Routine bloods: including electrolytes, Ca2+ and TFTs to rule out any pseduo-obstruction
* **CT scan abdo pelvis** with contrast
* **Abdominal radiograph**
56
What will you seen on abdominal xray if patient has a volvulus?
Coffee bean sign
57
What will you seen on CT scan if patient has a volvulus?
**whirl sign**
58
How are patients with sigmoid volvulus managed?
Mainly **conservatively** with initial **decompression by sigmoidoscope** and **instertus of flatus tube**
**Sigmoidoscope decompression** - patient placed in left lateral position and sigmoidscope inserted, twisted bowel is located, there will be a rush of air and liquid faeces as obstruction relieved
**Flatus tube** - left in situ for up to 24 hours to allow continued passage of contents. Unsuccessful in 25-50% of patients so formal flexi sig decompression required
59
When is surgery required for sigmoid volvulus?
When conservative management fails or:
* **Colonic ischaemia** or **perforation**
* **Repeated** failed attemps at decompression
* Bowel is **necrotic** on endoscopy
60
What are some of the complications of a sigmoid volvulus?
* Bowel ischemia
* Perforation
* Risk of recurrence
* Complications of stoma needed
* Overal mortality is **high** as patients are generally old, frail and multi-morbid
61
What is the typical age of onset for caecal volvulus?
Bimodal: 10-29 years and 60-79 years
62
How do the pre-disposing factors for caecal volvulus differ between the older and younger age groups?
**Younger patients:** intestinal malformation or excessive exercise
**Older patients:** chronic constipation, distal obstruction or dementia
63
What is pseduo-obstruction of the bowel?
**Dilation** of the colon due to an **adynamic bowel** in the **_absence_** of **mechanical obstruction**
64
What is believed to be the pathophysiology behind pseudo-obstruction?
Believed to be due to **interruption of the autonomic nervous supply** to the colon resulting in **absence of smooth muscle contraction**
65
What are some of the causes of pseudo-obstruction?
* **Electrolyte imbalces** or **endocrine disorders**
* including hypercalcaemia, hypothyroidism, hypomagnesaemia
* **Medication**
* opioids, calcium channel blockers, anti-depressants
* **Recent surgery, severe illness or trauma**
* **Neurological diseases**:
* Parkinson's, MS, Hirschsprung's disease
66
How do patients present with pseudo-obstruction?
* Abdominal pain
* Abdominal distension
* Constipation (but can have paradoxical diarrhoea)
* Vomiting (typically a late feature)
* O/E: abdomen is **distended** and **tympanic**
* Focal tenderness indicated **ischemia**
67
Which investigations should be done if suspecting pseudo-obstruction?
* Bloods for biochemical or endocrine causes
* U&E, Ca2+, Mg2+, TFTs
* Abdominal X-ray will show bowel distension but appears **no different** to a mechanical cause
* **CT abdo-pelvis with contrast** will show dilation of colon and exclude any mechanical twist and show any complications .g. perforation
68
How is pseudo-obstruction managed?
Mostly **conservatively**
* Make NBM
* Start IV fluids - monitor input and output
* NG tube if vomiting and aid decompression
* If does not resolve in 24-48hours needs **endoscopic decompression** and insertion of **fl****atus tube**
* If there is limited resolution try IV **neostigmine** (anticholinesterase)
* Consider TPN
69
When is surgery performed for pseudo-obstruction?
In the absence of ischemia or perforation, non-responsive cases may require **segmental resection +/- anastamosis**
Alternatively bowel can be decompressed long term e.g. **caecostomy** or **ileostomy**
