GI surgeries Flashcards
How do you take a surgical history?
Pain assessment with SOCRATES, past medical + surgical history.
How does bowel ischaemia usually present?
Sudden onset crampy abdominal pain, severity depending on length/thickness affected. Bloody, loose stool, fever, signs of septic chock
What is acute mesenteric ischaemia? When does it usually happen? How does it present?
- Small bowel obstruction usually occlusive due to thromboemboli (potentially AF), usually clot in SMA.
- Sudden onset presentation, severity varies
What is ischaemic colitis? What is it due to? How does it present?
Large bowel, usually due to non-occlusive flow states/atherosclerosis (eg artery blocked/narrowed). Milder/gradual onset, moderate pain and tenderness
What are risk factors for bowel ischaemia?
Age >65, cardiac arrhythmias (AF), atherosclerosis, hypercoagulation/thrombophilia, vasculitis, sickle cell, profound shock causing hypotension (eg cardiac surgery)
What are investigations done for bowel ischaemia?
- Blood (FBC for neutrophilic leucocytosis)
- VBG for lactic acidosis (low pH, metabolic acidosis).
- Imaging CTAP/CT angiogram to detect stenosis/disrupted flow/pneumatosis intestinalis
- endoscopy for mild/moderate cases can see oedema, cyanosis, ulceration of mucosa
What is lactic acidosis associated with?
Late stage mesenteric ischaemia & extensive transmural intestinal infraction
What sign is an unspecific sign of colitis (ischaemic colitis)?
thumbprint sign
What is conservative management for bowel ischaemia? When is it used?
- For mild/moderate cases of ischaemic colitis (never for SB ischaemia!!!)
- IV fluids, bowel rest (NBM), broad spectrum antibiotics, NG tube for decompression in concurrent ileus, anticoagulation, treat/manage causes.
- Do repeat regular abdo exams/imaging to see changes & signs of peritonitis (pushes away from conservative management)
What is surgical management of bowel ischaemia? When is it used?
- For SB ischaemia, signs of peritonitis/sepsis, haemodynamic instability, massive bleeding, fulminant colitis with toxic megacolon.
- Explaratory laparotomy (resection of necrotic bowel +/- open surgical embolectomy or mesenteric arterial bypass). -Or can do endovascular revascularisation (bal;oon angioplasty/thrombectomy) in those without signs of ischaemia (more chronic)
How does acute appendicitis usually present?
Periumbilical pain radiating to RLQ within 24 hours, associated with anorexia, nausea +/- vomiting, low grade fever, change in bowel habit
What are important clinical signs in acute appendicitis?
- mcBurney’s point (tenderness in RLQ - line between right ASIS and umbilicus)
- blumberg’s sign (rebound tenderness in RIF - right iliac fossa)
- roysing sign (RLQ pain on deep palpation of LLQ)
- psoas sign (RLQ pain on flexion of right hip against resistance)
- obturator sign (RLQ pain on passive internal rotation of hip with hip & knee flexion).
!!Signs not used as much as have imaging!!
What are investigations for acute appendicitis? What imaging is used and in what cases?
- Bloods (raised neutrophils, high CRP, urine possible mild pyruria/haematuria, electrolyte imbalance if vomiting).
- Imaging: gold standard is CT in adults. USS in children/pregnancy/breastfeeding. MRI in pregnancy if USS inconclusive. Diagnostic laparoscopy in persistent pain & inconclusive imaging
What is conservative management of acute appendicitis?
IV fluids, analgesia, IV or PO (per oral) antibiotics.
What do you do in case of abscess, phlegmon or sealed perforation? (in context of appendicitis)
Resuscitation + IV antibiotics +/- percutaneous drainage. Consider interval appendicectomy
What is surgical management of acute appendicitis? which is preferred and why?
Laparoscopic or open appendicectomy.
-Less pain, infection, hospital stay, easier return to work, cost, QOL with laparoscopic
what are types of intestinal obstruction? How are they classified?
- Intestinal obstruction is restriction of normal passage of contents.
1. paralytic ileus (abdomen full of pus irritating bowel and stopping peristalsis)
2. mechanical obstruction (classified by speed of onset - acute/chronic/acute on chronic, site - high or low (roughly synonymous with small/large bowel) - -> nature (simple or strangulating) - simple no damage to blood supply, strangulating blood supply cut off
What are causes of bowel obstruction in lumen, wall and outside wall respectively?
- lumen: faecal impaction, gallstone ileus
- walls: crohns, tumour, diverticulitis)
- outside wall (strangulated hernia, volvulus, obstruction due to adhesions/bands)
What are causes of small bowel obstruction?
Adhesions after surgery, neoplasia, incarcerated hernia, crohns
What are causes of large bowel obstruction?
Colorectal cancer, volvulus (twisting of bowel itself), diverticulitis, faecal impaction, hirshprung’s disease (lack of ganglia - no peristalsis)
What is the presentation of small bowel obstruction? What are signs? what sounds would we hear?
- Abdominal pain colicky and central, vomiting early onset, absolute constipation late sign, abdominal distension less significant.
- Signs: dehydration, increased high pitch bowel sounds. Absent bowel sounds later, diffuse abdominal tenderness
What is presentation of large bowel obstruction? Signs?
- Pain colicky or constant, vomiting late, absolute constipation early, distention early and significant.
- Similar signs with SB obstruction
How do you diagnose bowel obstruction?
Presence of symptoms. Should search for hernias and ab scars.
What are features suggesting strangulation?
Change in character of pain from colicky to constant, tachycardia, pyrexia, peritoneum bowel sounds absent/reduced, leukocytosis, high CRP
What types of hernias exist and when can strangulation happen?
Epigastric, umbilical, incisional, inguinal, femoral. If large defect bowel can go in and out without problem to blood supply, but if small defect higher chance of strangulation
What is richer’s hernia?
Knuckle of bowel caught but still continuity (without obstruction)
What investigations for bowel obstruction? What can be seen if normal or strangulating?
Bloods - WCC/CRP normal unless strangulation/perforation. U&E for electrolytes. VBG: if vomiting & hypokalaemia maybe metabolic alkalosis. If strangulation metabolic acidosis (lactic acidosis). Imaging: erect CXR/AXR
What is seen on imaging on small bowel obstruction?
Erect CXR/AXR: dilated small bowel loops >3cm proximal to obstruction (central)
What is seen on imaging in large bowel obstruction?
Dilated large bowel >6cm (if caecum 9cm) predominantly peripheral.
What does a CT abdo/pelvis show in bowel obstruction?
Shows transition point, dilation of proximal loops
What does an AXR show in small bowel obstruction?
Ladder patterns of dilated loops and central position, striations that pass completely across width of distended bowel
What does an AXR show in large bowel obstruction?
Distended large bowel peripherally, show haustriations of taenia coli (don’t extend whole width of bowel)
What can a CT show in bowel obstruction?
Can localise site of obstruction (transition point), detect obstructing lesions/colonic tumours, unusual hernias
What is conservative management of bowel obstruction and when is it done?
- In all except when sings of ischaemia/clinical deterioration.
- Supportive: NBM, IV fluids, IV analgesia, anti-emetics, correct electrolyte imbalance, NG tube for decompression, urinary catheter to monitor output. Gradually introduce food when pain & distention improve
What is done in case of faecal impaction?
Stool evacuation via manual, enema, endoscopic
What is done in case of sigmoid volvulus?
Rigid sigmoidoscopic decompression to straighten large bowel
What is done in case of small bowel obstruction? (adhesional)
Oral gastrograffin - highly osmolar iodinated contrast agent to resolve adhesional small bowel obstruction
What are indications for surgery In small bowel obstruction?
Haemodynamic instability, sepsis signs, complete bowel obstruction with signs of ischaemia, closed loop obstruction, persistent bowel obstruction >2 days after conservative management
What are operations done for bowel obstruction?
Exploratory laparotomy/laparoscopy, restoration of intestinal transit, bowel resection with primary anastamosis or temporary/permanent stoma formation
How does a GI perforation present?
Sudden onset severe abdominal pain with distension, diffuse abdominal guarding, rigidity, rebound tenderness. Pain with movement, nausea, vomiting, absolute constipation, fever, tachycardia, tachypneoa, hypotension. Decreased/absent bowel sounds
What are causes of GI perforation and how does each present?
- perforated gastric ulcer (sudden epigastric or diffuse pain, referred shoulder pain because irritation of diaphragm, history NSAIDS, steroids, recurrent epigastric pain)
- perforated diverticulum (LLQ pain, constipation)
- perforated appendix (worsening RLQ pain, anorexia)
- perforated malignancy (change in bowel habit, weight loss, anorexia, PR bleeding)
What are investigations done in GI perforation? What would you see in imaging?
- Bloods (neutrophilic leucocytosis, maybe high urea/creatinine, lactic acidosis
- imaging: erect CXR see subdiaphragmatic free air (pneumoperitoneum),
- CT abdo/pelvis shows pneumoperitoneum and free GI content, localised mesenteric fat stranding
What is conservative/supportive management on presentation of GI perforation?
NBM & NG tube decompression, IV fluids, broad spectrum Abx, IV PPI, parenteral analgesia & antiemetics, urinary catheter
What can you do if localised peritonitis without sepsis signs (rare)?
IV guided drainage of intra abdominal collection, series of exams for change/assessment
What surgical management done for generalized peritonitis with out without signs of sepsis in GI obstruction?
Exploratory laparotomy/laparoscopy, primary closure of perforation.
What do you do if duodenal perforation?
Omental patch to close it
Management if diverticulum perforation?
Resection of perforated segment of bowel with primary anastamosis or temporary stoma
Why should you take culture from perforation?
Perforations can be malignancy
What to do if appendix perforation?
Laparoscopic or open appendicectomy
How does biliary colic present? What is seen in blood? What is seen in USS? How do you manage it?
Post-prandial RUQ pain with radiation to shoulder + nausea. Blood normal. USS shows cholelithiasis. Manage with analgesia, antiemetics, spasmolytics + elective cholecystectomy
How does acute cholecystitis present? What is seen on bloods? What is seen on USS? Management?
Acute, severe RUQ pain, fever, murphy’s sign. Elevated WWC/CRP. USS shows thickened gallbladder. Manage with fluids, antibiotics, analgesia, blood culture + early or elective cholecystectomy
How does acute cholangitis present? What is seen on blood and USS? Management?
Charcot’s triad: jaundice, RUQ pain, fever. Elevated LFTs, WCC, CRP. USS shows biliary dilatation. Manage with antibiotics, fluids, analgesia, ERCP to clear bile duct or stenting
How does acute pancreatitis present? Bloods? CT/US? Management?
- Severe epigastric pain radiating to back, nausea +/- vomiting, history gallstones, alcohol use.
- Bloods show high amylase/lipase, high WCC/low calcium. CT & US assess complications/causes.
- Admission score (glasgow imrie score), aggressive fluid, O2, analgesia, anti-emetics, ITU/HDU involvement
How does sigmoid volvulus present? What is seen on imaging?
Large bowel obstruction, pain, grossly distended abdomen. ABX shows distended oval gas shadow looped on itself (coffee bean sign) & haustra don’t extend across width of gas shadow.
What conservative management is effective in treating majority of patients with sigmoid volvulus
sigmoidoscope passed with patient lying In left lateral position. Large well lubricated soft rubber rectal tube passed along sigmoidoscopy to untwist volvulus releasing flatus & liquid faeces
Risk of untreated sigmoid volvulus?
Loop of sigmoid with its blood supply cut off by torsion would undergo necrosis
If sigmoidoscopy does not work (serious sigmoid volvulus) what do you do?
Exploratory laparotomy & sigmoid colectomy with end colostomy (hartmann’s procedure) - take twisted part of bowel & resect, making colostomy.
What to do if serious sigmoid volvulus but bowel looks viable or patient not fit enough for bowel resection?
sigmoidopexy (not ideal)
If suspecting acute mesenteric ischaemia what do you do?
- Exploratory laparotomy (midline incision, evaluate viscera, if intestinal necrosis resect affected bowel loops).
- Damage control laparotomy - stapled off bowel ends may be left in discontinuity, re0inspect after period of ICU resuscitation to restore physiological balance
How do you restore blood flow in SMA?
- Embolectomy of SMA (in embolic AMI).
- Endovascular management of SMA thrombus (in thrombosis AMI).
- Arterial bypass of SMA (in thrombotic AMI)
What are arterial causes of acute mesenteric ischaemia?
- embolism (50%): from left auricle (AF), mural infarct, atheroma from aorta or aneurism, endocarditis vegetations, left atrial myxoma
- thrombosis (20-35%): blocks origin of SMA causing ischaemia to full length of small bowel. Due to atherosclerosis (often all main abdominal vessels)
- non-occlusive (rare): hypotension/hypoperfusion, vasospasm in shock (NOMI), critically ill with vasopressor requirement, undergoing dialysis with large volume fluid removal
Venous causes of AMI?
SMV thrombosis (in those with portal hypertension, portal pyaemia, sickle cell disease –> underlying hyper-coagulable state)
What is portal pyaemia (pyelophebitis)?
Form of septic (often suppurative) thrombophlebitis of portal venous system. Complications of intra-abdominal sepsis (diverticulitis, appendicitis). See air in SMV & intra-hepatic portal venous system
