Bowel Obstruction Management Flashcards
What are common symptoms of bowel obstruction?
Constipation
Vomiting
Distension
Abdominal pain +/- colic
Vomiting can be bilious in SBO and feculent in LBO.
List the causes of small bowel obstruction (SBO).
- Adhesions (Hx of abdominal surgery)
- Hernia
- Strictures (Crohn’s)
- Meckel’s diverticulum
- Intussusception
- Malignancy
Vomiting bilious in SBO
List the causes of large bowel obstruction (LBO).
- Tumour (60%)
- Volvulus
- Diverticular stricture
- IBD stricture
Vomiting feculent in LBO
What are the characteristics of non-mechanical obstruction (ileus)?
Vomiting is usually infrequent, pain is mild, and distention is moderate-severe
Imaging shows diffuse bowel obstruction with no transition point.
What are some causes of ileus?
- Post-op
- Peritonitis
- Drugs (e.g. opioids)
- Electrolyte disturbance: hypokalemia, hyponatraemia, hypomagnesaemia
What findings are noted during an abdominal exam for bowel obstruction?
- Bowel sounds (“tinkling”)
- +/- peritonism
What are signs of sepsis in a patient with bowel obstruction?
- HoTN
- Tachycardia
- Tachypnoea
- Pallor
Which blood tests are typically performed in cases of suspected bowel obstruction?
- FBC (pre-op)
- U&E: Check Ca2+, phosphate, and Mg2+ (Hypo-> ileus)
- Coag (pre-op)
- Group & save (pre-op)
- Amylase (increased in strangulation and perforation)
- VBG (increased lactate in ischaemia)
What imaging is commonly used first line for bowel obstruction?
Other Imaging?
PFA (Plain Film Abdomen)
Normal diameters:
* Small bowel: 3 cm
* Caceum 10-12 cm
* Ascending colon 8 cm
* Recto-sigmoid colon 6.5 cm
Other Imaging:
- CT abdomen with oral contrast - high sensitivity and specificity
- Gastrografin studies
- Barium study
What is the normal diameter of the small bowel?
3 cm
Normal diameters:
* Small bowel: 3 cm
* Caceum 10-12 cm
* Ascending colon 8 cm
* Recto-sigmoid colon 6.5 cm
What is the normal diameter of the caecum?
10-12 cm
Normal diameters:
* Small bowel: 3 cm
* Caceum 10-12 cm
* Ascending colon 8 cm
* Recto-sigmoid colon 6.5 cm
What is the normal diameter of the ascending colon?
8 cm
Normal diameters:
* Small bowel: 3 cm
* Caceum 10-12 cm
* Ascending colon 8 cm
* Recto-sigmoid colon 6.5 cm
What is the normal diameter of the recto-sigmoid colon?
6.5 cm
Normal diameters:
* Small bowel: 3 cm
* Caceum 10-12 cm
* Ascending colon 8 cm
* Recto-sigmoid colon 6.5 cm
What is the conservative treatment approach for bowel obstruction?
Drip and suck:
* NPO and insert wide-bore NGT
* Give IV fluids, analgesia, antiemetics, antibiotics
_____________ are performed in cases that do not resolve initially with conservative management.
Gastrografin studies are performed in cases that do not resolve initially with conservative management.
- PFA around 6 hours since oral contrast can check to see evidence of ongoing obstruction versus resolution.
- ~100 ml gastrografin reaches colon 6-12 hours later in SBO, then SBO is resolving and surgery may be delayed or avoided.
* Gastrografin may have therapeutic properties in resolving obstruction due to its osmotic effect on bowel wall oedema.
What are the indications for surgery in bowel obstruction?
- Closed loop obstruction
- Strangulation / perforation / sepsis
- Obstructing neoplasm
- Failure of conservative management (>72 hours)
What are the surgical options for small bowel obstruction?
75% SBO do not need surgery:
* Adhesiolysis
* Bowel resection
* Hernia repair
What surgical options are available for large bowel obstruction?
- Primary anastomosis with loop
- Hartmann’s
What are the prophylactic measures to prevent post-op ileus?
- Minimise intraoperative bowel handling
- Avoid fluid overload
- Minimise opiate use
- Encourage early mobilisation
What conservative management strategies are used for post-op ileus?
- Make nil-by-mouth
- Start fluid-balance chart
- Daily bloods, including electrolytes
- Encourage mobilisation as tolerated
- Reduce opiate analgesia
