Acute General Surgery, Small Bowel Pathology & Anorectal Conditions

1) Acute General Surgery & Acute Abdomen (Emergency Surgical Presentations)

A typical patient story

You develop sudden abdominal pain that worsens over hours, with nausea/vomiting, reduced appetite, fever, or pain that moves/settles in one area. Your GP/ED team is concerned about an “acute abdomen”  conditions that may need urgent imaging, antibiotics, or surgery.

Common emergency surgical causes

• Appendicitis (often right lower abdominal pain)
• Acute cholecystitis (inflamed gallbladder; often right upper pain)
• Bowel obstruction / incarcerated hernia
• Perforation (a “hole” in bowel/stomach) with peritonitis
• Diverticulitis (sometimes needs admission/surgery)
• Skin/subcutaneous infection (abscess, severe cellulitis; occasionally necrotising infection)

Assessment and tests (what ED/your doctor usually does)

History + exam

• Pain location, timing, migration, fevers, vomiting, bowel motions, urinary symptoms, pregnancy status, previous surgery, hernia history.
• Co- morbidities, Medications in particular blood thinning medication and drug allergies.

Blood tests (common examples)

• Full blood count (infection/anaemia), CRP, kidney function/electrolytes
• Liver function tests ± lipase (upper abdominal pain)
• Coagulation profile if surgery likely

Imaging (selected to match symptoms)

• CT scan (very common for undifferentiated acute abdominal pain; excellent for appendicitis/obstruction/perforation)
• Ultrasound (particularly useful for gallbladder disease; also pregnancy/gynecologic assessment)
• X-ray (sometimes used for obstruction/perforation screening)
• MRI (selected cases: pregnancy/young patients when avoiding radiation; complex soft-tissue problems)

Initial management (often starts immediately)

• Fasting (nil by mouth) if surgery is possible
• IV fluids, pain relief, anti-nausea medication
• Antibiotics when infection is suspected
• VTE prevention measures if admitted (compression ± medication as appropriate)

When is emergency surgery needed?

Emergency surgery is considered when there are features of:

• Peritonitis (severe tenderness/guarding), perforation, uncontrolled sepsis
• Bowel ischaemia/strangulation, closed-loop obstruction
• Failure of appropriate non-operative management in selected conditions
• Worsening clinical status despite resuscitation

Keyhole (MIS/laparoscopic) vs open surgery (laparotomy)

MIS (laparoscopic/keyhole) may be appropriate when:

• You are stable, anatomy is suitable, and imaging supports a safe MIS approach
• Common examples: laparoscopic appendicectomy, laparoscopic cholecystectomy, selected bowel obstruction/adhesiolysis cases.

Open surgery (laparotomy) may be required when:

• Severe infection, perforation, significant bowel distension, suspected ischaemia, complex anatomy, instability, or when safe progress isn’t possible laparoscopically.
• Your surgeon may start laparoscopically and convert to open for safety.

A) Appendicitis (acute appendix inflammation)

Common presentation

• Pain often begins near the umbilicus then moves to the right lower abdomen
• Nausea, reduced appetite, low-grade fever, pain with movement/cough

How it’s diagnosed

• Clinical assessment + bloods + imaging (CT common; ultrasound often used first in children/pregnancy)

Treatment options

• Laparoscopic appendicectomy is a standard treatment.
• In selected uncomplicated cases (not common practice in Australia), antibiotics-first (non-operative management) may be discussed, understanding recurrence/failure risks.

Key risks/complications

• Perforation/abscess if delayed, anaesthetic risks , wound infection, bleeding, injury to bowel/nearby structures, hernia at port sites , DVT/PE.

B) Acute cholecystitis (infected/inflamed gallbladder)

Common presentation

• Constant right upper abdominal pain, fevers, nausea/vomiting
• Often tenderness under the right rib margin (Murphy’s sign)

How it’s diagnosed

• Bloods (WCC/CRP + LFT changes) + ultrasound typically first line
• CT/MRI used when diagnosis is unclear or complications suspected

Treatment

• IV fluids + antibiotics + pain control
• Early laparoscopic cholecystectomy is commonly recommended when safe; some severe cases may need drainage or staged management depending on severity and patient factors.

C) Skin & subcutaneous infection (abscess / severe cellulitis)

Typical presentation

• Localised painful swelling (abscess), redness, warmth, tenderness
• Fever or rapid progression raises concern for deeper/severe infection

Treatment

• Incision and drainage is often key for an abscess
• Antibiotics depending on severity, systemic features, immune status, and organism risk profile

Common patient questions (Acute abdomen / appendicitis / cholecystitis / skin infection)

2) Acute Small Bowel Pathology (Focus: Small Bowel Obstruction)

A typical patient story

You develop crampy abdominal pain, vomiting, bloating, and you stop passing gas or stool. CT suggests small bowel obstruction (SBO) a time-critical condition because the bowel can become strangulated (loss of blood supply).

Common causes

• Adhesions (scar tissue) after prior abdominal surgery
• Hernias
• Inflammatory bowel disease (e.g., Crohn’s) strictures
• Tumours (less common depending on context)
• “Virgin abdomen” SBO (no prior surgery), needs careful evaluation

Tests commonly used

• CT abdomen/pelvis (most informative test: level/cause, closed-loop features, ischaemia signs)
• X-ray may show dilated loops/air-fluid levels
• Bloods: dehydration, electrolytes, lactate (if ischaemia suspected)

Non-operative management (when appropriate)

Many adhesive SBO cases can start with:

• Fasting, IV fluids, electrolyte correction
• Nasogastric tube if vomiting/marked distension
• Close monitoring; repeat exams and labs

The World Society of Emergency Surgery (WSES) Bologna guidelines outline when non-operative management is appropriate and when to proceed to surgery.

When surgery becomes urgent

Surgery is more likely if there are signs of:

• Strangulation/ ischaemia, peritonitis, perforation
• Closed-loop obstruction, worsening pain, rising inflammatory markers/lactate
• Failure to improve with an appropriate trial of conservative care

What the operation may involve

• Laparoscopic adhesiolysis (selected patients; surgeon-dependent and anatomy-dependent)
• Emergency laparotomy when complex/severe
• Possible bowel resection if a segment is non-viable
• Occasionally a temporary stoma is needed (depending on situation)

Common patient questions (Small bowel obstruction)

3) Acute anorectal Conditions (Perianal Abscess) and Pilonidal Infection

A typical patient story

You develop severe pain near the anus or cleft, swelling, fevers, and it becomes difficult to sit or move. This may be an abscess that needs drainage.

A) Perianal abscess (sometimes associated with fistula)

Common presentation

• Throbbing anal/perianal pain, swelling, fever, discharge
• Occasionally deeper abscess causes rectal pain without obvious swelling

Diagnosis

• Clinical exam is key
• Imaging (e.g., MRI/CT) is sometimes used for complex/recurrent disease or when a fistula is suspected

Treatment

• Incision and drainage (I&D) is the mainstay
• Antibiotics may be added in selected cases (systemic illness, immunocompromise, extensive cellulitis, etc.)

Key risks

• Recurrence, development of a fistula, bleeding, pain, wound healing time; continence disturbance is uncommon but can be relevant in complex fistula surgery.

B) Pilonidal infection (natal cleft abscess/sinus)

Common presentation

• Painful swelling in the top of the buttock cleft, redness, drainage, fever

Treatment

• Acute abscess: drainage + wound care
• Preventing recurrence: hair control, hygiene, reducing cleft friction/pressure

Common patient questions (Anorectal abscess / pilonidal)

Quick summary (for patients + referring doctors)

• Acute abdominal pain can represent time-critical surgical disease; early assessment and imaging are essential.
• MIS/keyhole surgery is commonly used for appendicitis and gallbladder disease, and sometimes for selected bowel obstruction cases, but open surgery remains vital when safety requires it.
• SBO often starts with careful non-operative care when appropriate, with a low threshold for surgery if red flags appear.
• Perianal and pilonidal abscesses frequently need drainage; recurrence/fistula risk requires proper follow-up.