Colorectal Surgery Flashcards
What are the main types of surgeries for colorectal conditions?
Open surgery
Endoscopic treatment
Minimally invasive techniques - laparoscopic, robotics and NOTES
What is the function of the colon?
Water and electrolyte absorption
Production and absorption of vitamins
Storage of faeces
Hosts gut microbiota
Describe the arterial supply of the colon and the rectum
Superior and inferior mesenteric artery
Marginal artery is important
Superior, middle and inferior rectal artery
What is the venous drainage of the colon and rectum
Superior and inferior mesenteric vein
Describe the nerve supply of colon and rectum
Parasympathetic - vagus and C2,3,4
Sympathetic
What are some important factors causing continuence?
Anatomy
Rectal compliance
Stool consistency
Central control
Anorectal sensation
What is screening?
Identification of unrecognised disease in apparently healthy individual in asymptomatic population by means of tests
What is the screening for colorectal cancer in Scotland?
Age 50-74
Every 2 years
Quantitative faecal immunochemical test (qFIT)
What are ways to screen for colorectal cancer?
qFIT
Replaced faecal occult blood test (FOBT)
Once off flexible sigmoidoscopy
What are some different types of polyps?
Pedunculated polyp
Flat, FAP, giant, multiple
Describe a polypectomy
Removal of polyp with hot snare
Colonoscopy guided
What are the symptoms of colorectal cancer?
Abdominal pain, rectal bleeding, change in bowel habits, weight loss, tenesmus, fatigue and vomiting
What are some investigations used for colorectal cancer?
Colonoscopy and biopsy - gold standard
CT colonography, Plain CT abdo/pelvis
Pre-op MRI and PET
What are the most common tumour locations in colorectal cancer?
Mostly proximal colon, then distal colon then rectum
Describe pre-op management for colorectal cancer
MDT discussion
Anaesthetic assessment and stoma nurse appointment
Colon cancer usually straight to surgery if no metastases but rectum has neoadjuvant chemo or RT
What are some rectal cancer basic surgical principles?
Rectum surrounded by fatty envelope called mesorectum which had lymph nodes
The rectum and mesorectum has to be excised
Why is there pre-op MRI for rectal cancer?
Best for looking at CRM - circumferential resection margins
Restaging after 6-8 weeks following neoadjuvant treatment
Surgery 8-10 weeks after treatment
When is neoadjuvant treatment needed for rectal cancer?
CRM threatened disease, extramural venous invasion (EMVI), nodal disease and very low rectal cancer
What is the treatment for colorectal cancer?
Surgical or medical
Open or minimally invasive
Palliative if advanced metastatic disease
What is a right hemicolectomy?
Cecum, ascending colon and part of transverse colon removed
Ileocolic artery removed
What are the principles for bowel anastomosis?
Tension free, well perfused, well oxygenated, clean surgical site and acceptable systemic state
What are the 2 stoma types?
Ileostomy and colostomy
Describe an ileostomy
Usually RIF
Contents are liquid and looser stools
Appearance is spouted
Describe a colostomy
Usually LIF
Contents are solid stools
Appearance is no spout and flush with skin
What are the complications with with surgery?
Bleeding, infection, anastomotic leak and stoma problems - ischaemia, retraction, prolapse, hernia, high output
What are some complications with low anterior resections?
Damage to pelvic nerves - bowel, urinary and sexual dysfunction
Possible impaired fecundity in younger women
What is the pathological staging used for colorectal cancer?
TNM staging
Describe the post-op management of rectal cancer
Dependant on pathological staging
Presence of high risk pathological features
Adjuvant chemo may be needed (FOLFOX)
Surveillance CT CAP, colonoscopy
USS liver and CT CAP
What are the cardinal signs and symptoms of bowel obstruction?
Abdominal pain, vomiting, absolute constipation (flatus and solids) and abdominal distention
What is the aetiology of large bowel obstruction?
Malignant or benign
Benign - structures, volvulus, faecal impaction, intussusception, pseudo-obstruction
What is the aetiology of small bowel obstruction?
Adhesions and hernias
What is the management of bowel obstruction?
ABC, fluid resus, nasogastric tube, analgesia and antiemetics, IV antibiotics
Bloods, blood gas and CT abdo/pelvis
What is PEARLS?
If closed loop obstruction then needs urgent surgical review
Normal lactate does not exclude ischaemia
Pain out of proportion suggests ischaemia or perforation
What are the treatment options for small or large bowel obstruction?
Sigmoid colectomy and primary anastomoses
Hartmanns procedure
Defentioning colostomy
Colonic stenting
Do nothing
When should you not perform an anastomosis?
No reservoir, rectal compliance and previous traumatic birth
Better off with stoma
