Gastrointestinal Surgery Flashcards
ACUTE ABDOMEN
Acutely ill where signs and symptoms are chiefly abdominal; Abdominal pain and tenderness,
Colicky pain, Distention and swelling etc
ACUTE ABDOMEN Investigations and Management
• Investigations – U&E, FBC, Amylase, LFT, CRP, ABG (? Ischaemia), Blood cultures
o AXR, CT and USS Abdo, CXR if >50yrs or Peritonitis; ECG if >50yrs
o Rigler’s Double Wall Sign and Football Sign – Pneumoperitoneum
o Sentinel Loop – Focal area of Adynamic ileus provides clues as to source of
inflammation e.g. Appendicitis, Pancreatitis
• Initial Management – Management of Shock (Oxygen, Fluid resuscitation), Crossmatch and
G+S, Antibiotic Prophylaxis, Pain Management, Nil by mouth in case of emergency surgery
o Broad spectrum regime e.g. Cefuroxime and Metronidazole
Differential Diagnosis • Organ Rupture
(Spleen, Aorta, Ectopic Pregnancy); Hypovolaemic shock would be key
presentation; History of blunt (Spleen, may occur weeks after) or penetrating (Liver) trauma
o Always exclude pregnancy in females of reproductive age
Differential Diagnosis • Peritonitis
(Peptic Ulcer Disease, Diverticulum, Ruptured Appendicitis, Bowel Perforation, Gallbladder perforation); Prostration, Shock, Lying still and pain on coughing
o Abdominal rigidity + Guarding, Absent bowel sounds, Tenderness ± Rebound
Differential Diagnosis • Local Peritonitis
Diverticulitis, Cholecystitis, Salpingitis, ± Abscess formation
Differential Diagnosis • Colic
– Regular, waxing/waning pain rhythm caused by spasm of hollow viscera e.g. Intestine Ureter, Bile ducts (NB: Gallbladder pain typically dull and constant)
Differential Diagnosis • Intestinal Obstruction
Vomiting, Nausea, Anorexia, Colic and Constipation (Discussed in
subsequent section)
Differential Diagnosis
• Surgical Emergencies
Mesenteric Ischaemia, Acute Pancreatitis, Ruptured AAA
Differential Diagnosis
Medical Causes
Irritable Bowel Syndrome, MI, Infective (Pneumonia, Gastroenteritis, Herpes Zoster, Typhoid, Cholera), Metabolic (Diabetic Ketoacidosis, Porphyria, Thyroid)
Peritonitis
• Acute inflammation of the Peritoneal cavity; Primary Peritonitis typically due to streptococcal
infection via bloodstream; Secondary causes more common
• Secondary Peritonitis – Appendicitis, Ruptured Diverticular disease, Upper GI perforation,
Perforated ischaemic bowel, Perforated tumours, Acute Pancreatitis
• Could also be Post-operative complication, Complication of Peritoneal dialysis
Presentation of Peritonitis
• Anorexia, Fever, Severe Generalised abdominal pain which may radiate to shoulders and
back; Worsen on movement, coughing and sneezing
• Tachycardia, Guarding, Abdominal rigidity, Palpable masses
Diagnosis and Management of Peritonitis
• Investigations – FBC (Neutrophilia), CRP, Amylase, CT Abdomen, Exploratory laparoscopy
• Emergency Management – Large IV access, Catheterisation, Blood for FBC, U&E, CRP,
Amylase, G+S, NBM and ABG
Anatomy of Appendix
• Vermiform appendix located at the end of the Caecum
near the Ileocaecal junction; Has its own mesentery
(Mesoappendix) and sole blood supply (Appendiceal
Artery, Br Ileocaecal artery)
• Most commonly Retrocaecal, also Pelvic or Subcaecal
• Taenia Coli converge at base of the Appendix
Presentation of Appendicitis
• Classically central pain migration to RIF associated with N+V, Anorexia; Occurs in less than half
• Most common presentation Abdominal pain exacerbated by movement; Generally unwell,
weak, cold, clammy; Migratory pain is strongest symptom associated with Appendicitis
• Guarding, Rebound or Percussion tenderness suggests Local Peritonism; Rosving’s and Psoas
sign are of limited diagnostic value
• If no signs of Peritonism, Normal blood results and Normal US, Very low risk of Appendicitis
• Alvarado score (≥7 predictive; <5 against) – RIF tenderness (2), Rebound Tenderness (1), RIF
migratory pain (1), Anorexia (1), N+V (1), Fever (1), Leukocytosis (2), Left shift neutrophils (1)
Pathology of Appendicitis
• Neutrophilic infiltrate of the Muscularis Propria (Circular and Longitudinal layers)
• May progress to Perforation, forming a Mass (Densely adherent Caecum and Omentum
forming a mass), RIF abscess (Retrocaecal) and Pelvic abscess (Pelvic)
• Caused due to blockage of the appendix opening leading to increased pressure, decreased
perfusion and increased bacterial growth leading to inflammation and distention
o Blockage commonly caused by calcified faeces or inflamed lymphoid tissue
Differential Diagnosis for RIF Pain Children
Non-specific Adenitis, Merkel’s Diverticulum, Ovarian cyst/Menstrual symptoms
Differential Diagnosis for RIF Pain Adults
Crohn’s, Merkel’s Diverticulitis, Gastroenteritis, Pancreatitis, Renal colic, Ectopic
pregnancy, Ovarian cyst, Infection, Menstrual pain
Differential Diagnosis for RIF Elderly
Caecal Diverticulitis, Caecal tumours, Sigmoid Diverticulitis, Ovarian cysts, tumours
Management of Acute Appendicitis
• A-E Assessment
• FBC, U&E, CRP, Blood cultures, Crossmatch if required
o Beta HCG for Women of Childbearing Age
o Urinalysis – Renal Colic, UTI; NB: Pyuria can occur due to Appendicitis in 40%
o Elevated WBC, CRP, Neutrophilia suggestive of Appendicitis
• CT with IV contrast offers best chance of diagnosis; CI in Pregnancy and Young; Alternatively,
US or MRI; Identifies inflammatory response to Appendicitis
• IV Antibiotics given at induction; continued if perforated
• Evidence of Sepsis require urgent surgery; IV Abx alternatively for high-risk, or unfit
• Open or Laparoscopic Appendicectomy – Open approach involves Gridiron incision over
McBurney’s point (1/3 between Umbilicus and ASIS)
INTESTINAL OBSTRUCTION
- Mechanical/Functional obstruction of the Intestine which can occur distal to Duodenum
- Presents with Abdominal pain, Distention, Vomiting ± Faecal, Constipation
Small Bowel Obstruction
tends to be Colicky, central pain; Vomiting may occur before constipation while Large Bowel Obstruction tends to be lower in the abdomen and felt for
longer; Constipation occurs earlier and vomiting may be less prominent
Complicated by Dehydration, Electrolyte disturbances, Aspiration, Respiratory compromise
due to distention, Bowel Ischaemia or perforation
Simple obstruction
One point and no vascular compromise
Closed loop obstruction
2 points forming loop of grossly distended bowel; >12cm requires
urgent decompression
Strangulation
Compromise of blood supply; Sharper pain, more constant and localised;
Peritonism, Fever and ↑WBC (Mesenteric Ischaemia)