Introduction

• Appendicitis is one of the most common surgical conditions you will face in general surgery.
• It is the 2nd most common cause of abdominal pain, after non-specific abdominal pain, on the surgical take.
• As a surgeon, an appendicectomy will likely be the first abdominal surgery you will learn to perform.
• The diagnosis of acute appendicitis may generally be seen as an easy diagnosis to make, but it is an exceedingly difficult diagnosis to rule out.
• In clinical practice, you will be surprised how diverse the presentations for acute appendicitis can be.

Definition

Appendicitis is defined as inflammation of the vermiform appendix.

Incidence

The lifetime incidence of acute appendicitis is 8.6% in males and 6.7% in females.

Gender Distribution

• Note there is a slight preponderance of acute appendicitis in males compared to females.
• Females are more likely to undergo a negative appendicectomy (38.5% versus 6.2% in males in some studies).

Age Distribution

• Appendicitis can occur at any age!!
• Most commonly observed in age range of 5-45 yo.
• The mean age of presentation is 26.
• It is mostly a disease of childhood, adolescence.

Clinically relevant anatomy

• The appendix is a blind true diverticulum of the colon.
• It extends from the posterior aspect of the cecum towards the RIF.
• Found laparoscopically in the RIF, at the point where the taenia coli of the ascending colon converge.

McBurney’s point:

• A point found 2/3 of the length of a line drawn from the umbilicus to the right ASIS. Pain at palpation of this point makes a patient “McBurney’s positive.”
• Most appendices will lie retrocecally (65% of the time).
• An appendix with a diameter of over 6mm or a wall thickness of over 3mm is considered thickened and pathological.

Appendicular neurovascular supply

• It is supplied by the Appendiceal artery, a branch of the Ileocolic artery which is a branch of the SMA.

Nerve supply

• Pain from appendicitis typically presents as a vague paraumbilical pain which localises to the RIF.
• Pain at paraumbilicus: felt there as the appendix is supplied by sensory fibres that enter thespinal cord at level of T10 (T10 dermatome is the umbilicus).
• pain at the RIF: this is felt when the inflammation worsens and starts irritating the parietal peritoneum of the posterior abdominal wall.

Appendicitis Pain Patterns

Initial Pain

• Pain from appendicitis typically presents as a vague paraumbilical pain.
• It is felt there as the appendix is supplied by sensory fibres that enter the spinal cord at level of T10 (T10 dermatome is the umbilicus).

Pain Localization

• The pain later localises to the right iliac fossa (RIF) as the parietal peritoneum becomes involved.
• Pain at the RIF is felt when the inflammation worsens and starts irritating the parietal peritoneum of the posterior abdominal wall.

Pathophysiology of Acute Appendicitis

Clinical Presentation: Symptoms

Clinical Presentation: Examination Findings

Tenderness

Maximal at McBurney's point, one-third of the distance from the anterior superior iliac spine (ASIS) to the umbilicus.

Rebound Tenderness

Indicates peritoneal irritation.

Guarding

Voluntary or involuntary muscle contraction in response to peritoneal inflammation.

Percussion Tenderness

Pain upon gentle tapping of the RIF.

RIF Mass

May indicate an appendiceal abscess.

McBurney's Sign

Maximal tenderness at McBurney's point.

Rovsing Sign

Pain in the RIF upon palpation of the left iliac fossa (LIF), due to peritoneal stretch.

Psoas Sign

Pain on extending the right hip, indicating retrocaecal appendicitis.

Dunphy's Sign

Increased pain in the RIF with coughing.

Differential Diagnosis:

GI Causes

Inflammatory Bowel Disease (IBD)

Can present with RIF pain. Remember the most common site for Crohn's disease is the terminal ileum (which is also in the RIF). Patient will most likely have a preceding history of loose stools, PR bleeding and PR mucus. A short sudden history of RIF pain makes this unlikely (but not impossible).

Meckel's Diverticulum

Meckel's diverticulitis is a complication of Meckel's diverticulum, can have a very similar presentation to appendicitis. It's the commonest congenital malformation of the small bowel. Pathology: True diverticulum of the ileum, forms due to failure to obliterate the vitelinointestinal duct during the 5th week of fetal development.

Diverticulitis

Patients with right-sided diverticulitis tend to be younger than those with left-sided disease and often are misdiagnosed with acute appendicitis. CT scans will differentiate this from appendicitis.

Gynaecological Causes

Mittelschmerz Pain

Refers to midcycle pain in an ovulatory woman caused by normal follicular enlargement. Pain typically mild and unilateral, around midpoint of menstrual cycle.

Ovarian Cyst

Can cause pain similar to appendicitis.

Ectopic Pregnancy

Positive pregnancy test, septic, hypovolemic shock.

Endometriosis

Chronic history, short history and sudden onset pain makes this less likely.

Ovarian Torsion

Can present with acute abdominal pain.

Pelvic Inflammatory Disease

Important to take a full sexual history to discern patients who are most at risk of STIs. Ask about vaginal discharge. Can progress into tuboovarian abscess and involve bladder/bowel.

Urological Causes

Renal Colic

Loin to groin pain classically. Severe pain, patient will be unable to sit still, in severe pain. NOTE: a positive urine dip for blood, leukocytes doesn't rule out appendicitis. A retrocecal appendix can present with a positive urine dip and loin pain.

Urinary Tract Infection (UTI)

Dysuria, off smell to urine, pain not localised to RIF.

Pyelonephritis

Can present with flank pain and fever.

Testicular Torsion

Acute scrotal pain that can be confused with appendicitis.

Epididymorchitis

Inflammation of the epididymis and testicle that can mimic appendicitis.

Pediatric Causes

Mesenteric adenitis

• Refers to inflamed abdominal lymph nodes. This presents with abdominal pain in younger children.
• Usually preceded by or associated with tonsillitis or an upper respiratory tract infection.
• Fevers tend to be high grade (39°C or above) compared to lower grade fevers in appendicitis.
• The condition is self-limiting.

Diagnosis: Imaging - Ultrasound (USS)

Purpose

To visualise a distended appendix and rule out gynaecological causes of RIF pain.

Diagnostic features on USS

Maximal Outer Diameter (MOD)

Refers to the diameter of the appendix. Defined on ultrasound as the distance between the outer hyper echoic borders of the appendix. Over 6mm is considered pathological.

Maximal Mural Thickness (MMT)

The thickness of the appendiceal wall. Defined as the distance from the hyper echoic luminal interface to the outer hyper echoic border. Over 3mm is considered pathological.

Free Fluid

Presence of free fluid in the abdomen is also to be noted. Free fluid in females may be physiological or pathological. In males it is always pathological and raises concern for a perforated hollow viscus.

Diagnosis: Imaging - CT Scan

Purpose

Provides detailed imaging and helps confirm the diagnosis of appendicitis.

Diagnostic features on CT scan

Appendix Diameter

Appendix diameter over 6 mm is considered abnormal.

Wall Thickness

Appendiceal wall thickness over 3 mm (target sign) indicates inflammation.

Periappendiceal Inflammation

Fat stranding around the appendix is a sign of inflammation.

Faecolith

Presence of a faecolith can be seen on CT.

Cecal Changes

Thickened cecum funnelling contrast into the appendix can be observed.

Diagnosis: Laboratory Tests - Blood Tests

White Blood Cell Count (WBC)

A rise in neutrophils indicates infection and inflammation.

C-Reactive Protein (CRP)

Elevated levels suggest inflammation, but normal levels do not rule out appendicitis.

Bilirubin

Elevated levels may indicate perforation.

Diagnosis: Laboratory Tests - Urine Tests

Urine Dipstick

To rule out urinary tract infections (UTI) as a cause of the pain. Presence of leukocytes, blood, and nitrites can be seen in retrocolic appendicitis due to ureteric irritation.

Beta-HCG

Essential for ruling out pregnancy and ectopic pregnancy in women of childbearing age, which is crucial before performing surgery or imaging involving radiation.

Management of Acute Appendicitis: Initial Management

Patient Assessment

• Patients may be unwell and septic on presentation.
• Use principles of sepsis 6 and CCRISP protocol to manage the patient.

Early Interventions

• Early administration of antibiotics and IV fluids is important.
• Insert a urinary catheter to guide fluid prescribing and resuscitation.

Preparation for Surgery

• Patient to be made nil by mouth (NBM) from time of assessment to fast for potential surgery.

Pain Management

Pain management should ensure patients are kept comfortable.

Monitoring

Input-output accurate measurement is essential to prevent acute kidney injuries, dehydration, and electrolyte disturbances.

Management of Acute Appendicitis: Definitive Management

Non-operative Management

• a potential management plan, especially in elderly patients, patients unfit for surgery, patients not agreeable to surgery
• Effective in 70-90% of uncomplicated appendicitis cases. However, there is a high risk of recurrence (15-30%).
• Presence of a faecolith increases risk of complications and recurrence very significantly.
• In older patients, you need to exclude an occult malignancy with a colonoscopy.

Surgical Management

• A laparsocopic appendicectomy is the standard management of acute uncomplicated appendicitis.
• For details notes on laparoscopic appendicectomy, scroll to the top and use the surgical view tab.

Management of Complicated Appendicitis

The natural progression of appendicitis, if left untreated, can result in various outcomes:

• Resolution

  In rare cases, the inflammation may subside on its own.

• Generalized Peritonitis
  • If the appendix undergoes necrosis, it may lead to a large perforation.
  • This perforation can cause the release of infectious material into the abdominal cavity, resulting in generalized peritonitis—a severe and life-threatening condition.
• Appendix Mass or Phlegmon Formation
  • The inflamed appendix may become surrounded by omentum and adjacent small bowel.
  • This forms a protective barrier, or "walling-off," that confines the inflammatory process and prevents it from spreading to the rest of the abdominal cavity.
• Appendiceal Abscess
  • An abscess may develop in the periappendiceal region, encapsulating the infection within a localized, walled-off area.

Management strategy is different in complicated appendicitis as presence of an abscess or a phlegmon increases risk of surgical complications.

Management of generalized peritonitis

Should be operated on to control the source of sepsis, washout, drain insertion

Management of perforated appendix causing phlegmon

1. Managed non-operatively with abx with or without interval appendicectomy.
   • Failure rate of abx only is 7%
   • Risk of recurrence 7-40%
   • Risk of important benign disease being missed is 7%.

2. Managed operatively with immediate appendicectomy.

   • No risk of recurrence of appendicitis
   • HIGH RISK OF COMPLICATIONS: due to severe surrounding inflammation and adhesions.
   • 20% may need cecectomy
   • 30% may need ileocolectomy.

3. Therefore, an initially nonoperative approach, with subsequent interval appendectomy is certainly a reasonable strategy,

4. The role for a subsequent interval appendicectomy is debatable.
5. A large systematic review showed

Appendiceal abscess management

• These are generally diagnosed preoperatively because imaging is now a routine part of the diagnostic process.
• Abscess will form in one of the following locations:
  1. right paracolic gutter
  2. subcecal area
  3. pelvis
• There are three general approaches management:
  1. Percutaneous drainage with interval appendectomy
  2. Percutaneous drainage without appendectomy,
  3. Immediate operative drainage and appendectomy.
     • higher risk of requiring a further resection (same as phlegmons).

Post operative complications

Hospital stay:

• Full diet and early mobilisation is recommended as soon as possible post-op
• most patients who are comorbidity free can be discharged within 24 hours of an appendicectomy
• prolonged hospital stay is more common in patients with other comorbidities, or those frail and unlikely to return to their premorbid state, requiring care arrangements on discharge.

Wound infection

• The commonest post operative complication of an acute appendicectomy
• less common in patients done laparoscopically compared to patients done open.
• wound is usually superficial requiring a course of oral abx.
• deeper infections may lead to dehisence of the wound. Management of this may require washout of wound, drainage of any associated soft tissue abscess and prolonged dressings.

Collection formation

• pericaecal fluid collections are relatively common

5-10 days post op

• present with post-op discomfort and low grade pyrexia—> collection
• swinging pyrexia and pain—> abscess.
• management of both is IR guided drainage and prolonged course of iv abx. Surgical washout maybe indicated in patients who are in shock, or those who dont respond to conervative management.

first 48 hours post op

• fevers, pain, septic shock, peritonism in the first 24 hours may indicate dissemination of infected fluid or inappropriate washout of purulent fluid.
• The main differential diagnosis is iatrogenic injury to small bowel during port zinsertion or otherwise intraoperatively.
• early washout and diagnostic laparoscopy is recommended in those patients.

Appendicitis (Surgeon's view)

This page will provide a comprehensive overview of the laparoscopic appendectomy procedure, from patient consent to surgical technique and postoperative care.

Patient Consent: Understanding the Procedure

Incisions

Brief explanation:

• 3 small cuts in abdomen.
• long camera and instruments used
• appendix removed

Conversion

• may be converted to open if surgery complicated, difficult or unsafe to perform lapoaroscopically, larger incision used, more pain, slower recovery
• I like to use the diagram below to explain lap converted to open

Risks Associated with Surgery

Laparoscopic appendicectomy

Cost issues

• This has now considered the gold standard for an appendicectomy in adult patients.
• Due to increased cost of equipment associated with laparoscopy, open appendicectomy has remained the standard practice in some developing countries.

Compared to open:

• Multiple meta-analyses confirmed(1) (2)
  • benefits including:
    • faster recovery
    • smaller scars
    • lower incidence of wound infection
  • Risks including:
  • 3x increase in risk of post op collection
  • longer opening time (16 minutes longer on average)

1) Golub R, Siddiqui F, Pohl D. Laparoscopic versus open appendectomy: a metaanalysis. J Am Coll Surg. 1998 May;186(5):545-53. doi: 10.1016/s1072-7515(98)00080-5. PMID: 9583695. 2) Sauerland S, Lefering R, Neugebauer EA. Laparoscopic versus open surgery for suspected appendicitis. Cochrane Database Syst Rev. 2002;(1):CD001546. doi: 10.1002/14651858.CD001546. Update in: Cochrane Database Syst Rev. 2004 Oct 18;(4):CD001546. doi: 10.1002/14651858.CD001546.pub2. PMID: 11869603.

Pre-operative Patient Preparation

Post scrubbing in: Surgical Field Preparation

Antiseptic Application

Use 4% chlorhexidine (or follow local guidance) to thoroughly clean the entire abdomen, paying special attention to the umbilicus.

Draping

Carefully drape the surgical field to maintain sterility.

Antibiotic Administration

Ensure prophylactic antibiotics are administered as per protocol.

Surgical Team Positioning

Position the surgeon on the patient's left side and the assistant on the right initially, with the assistant moving to the left after port insertion.

Port Placement for Laparoscopic Appendectomy

Port	Size	Insertion Technique	Use
Umbilical	5-12mm	Modified Hasson	Camera port
LIF	5mm	Under direct vision	Right hand instrument
Suprapubic	5mm	Under direct vision	Left hand instrument

First Port Insertion: Modified Hasson Technique

Incision

• Grasp the umbilical stalk with a littlewoods forceps.
• Make an infraumbilical or supraumbilical transverse curved incision using a size 11 blade.

Dissection

Dissect the fascia and fat surrounding the umbilical stalk.

Move your littlewoods forceps deeper as you dissect downwards closer to fascia

Continue dissecting until you visualize rectus sheath.

Peritoneal Entry

Make a vertical midline incision at the junction of the umbilical stump and linea alba.

Port Insertion

Insert a blunt trocar, pointing away from major vessels, and establish pneumoperitoneum.

Establishing Pneumoperitoneum

Insufflation

Insufflate the abdomen to create a working space for the procedure.

Pressure Maintenance

Maintain intra-abdominal pressure between 12-15 mmHg using high flow.

Monitoring

Be prepared to release pneumoperitoneum if the anesthesiologist reports ventilation difficulties or reduced venous return.

Insertion of Secondary Ports

LIF Port

• 2 fingerbreadths superior and medial to the left ASIS
• You need to avoid injury to left inferior epigastric vessels
  • shine camera into peritoneum internally, you should see epigastric vessels
  • go medially or laterally to them

Suprapubic Port

• inserted to triangulate with 2 other ports.
• ensure bladder is not going to be injured.
• if this is challenging perform a trendelenberg manouver to get small bowel out of the way.

Visualization

• Use camera guidance to ensure safe insertion of both secondary ports.
• Position the patient in Trendelenberg position to allow small bowel to move to the superior part of the abdomen with gravity to ease visualisation of the appendix.

Diagnostic Laparoscopy

Thorough Examination

Assess the gallbladder, large bowel, small bowel, and in females, examine the ovaries.

Normal Appendix?

If the appendix appears normal, examine the terminal ileum for Meckel's diverticulum.

Washout

• Aspirate any purulent fluid for microbiology and perform a washout.
• this is to avoid contaminating further quandrants of the abdomen when you perform a steep trendelenberg later

Documentation

Record all findings for accurate post-operative reporting and follow-up.

Locating the Appendix

Teniae Coli Guidance

Follow the convergence of the three thickened bands of longitudinal muscles (teniae coli) to find the appendix base.

Appendix Manipulation

Once found, grasp the appendix with the left hand and pull it anteriorly, laterally, and caudally to visualize the mesoappendix.

Reach the base of the appendix

• Use a combination of blunt and sharp dissection to reach the base of the appendix.
• This allows complete resection of the appendix
  • remember! a subtotal cholecystectomy is a good operation, a subtotal appendicectomy on the other hand isnt!!

Dissecting the Mesoappendix

Aim

aim to clear the mesoappendix at the base of the appendix to prepare for ligation of the base.

Window Creation

Use hook diathermy to create a window in the mesoappendix.

Careful Dissection

Dissect through layer by layer, only cutting tissue that is clearly visible to avoid vessel injury.

Vessel Management

Cauterize the appendiceal artery when identified. Use clips for larger vessels if necessary.

Base Preparation

Clear the mesoappendix at the base to prepare for appendix ligation.

Resecting the Appendix

Endoloop Placement

Place Vicryl or PDS endoloops at the base of the appendix.

• endoloop in right hand, grasper in left hand
• insert grasper though the endoloop
• grasp appendix tip with left hand and pull it through the loop.

Ligation Technique

Apply two proximal loops close together and one loop 1cm distally.

Appendix Division

Cut the appendix between the loops, leaving two endoloops on the stump and one to keep the appendix closed during removal.

inspect base of the appendix and surrounding area to ensure good haemostasis.

Removing the Appendix

Retrieval Bag Insertion

• Insert a retrieval bag through the umbilical port.
• push bag towards liver to make space
• insert camera throough same port

Appendix Placement

Use two graspers to place the appendix into the bag.

Bag Removal

Carefully pull the bag containing the appendix through the umbilical port.

Appendix Inspection

• inspect the removed specimen, make sure its an appendix *small pouch with a lumen
• you will be surprised sometimes a lump of fat or a lymph node may be mistaken for an appendix!

Peritoneal Washout

Thorough Irrigation

Perform a good washout of the peritoneal cavity until the fluid runs clear.

Pelvic Clearance

Ensure all fluid in the pelvis is cleared to prevent postoperative collections.

Drain Insertion Considerations

Current Evidence

Meta-analyses show drains have no effect on intra-abdominal collections in complicated appendicitis.

Potential Risks

Drains may increase the risk of postoperative complications such as fistula, surgical site infection, bowel obstruction, and ileus.

Decision Making

Consider the individual case and surgeon preference when deciding on drain placement.

Removal of Ports and Closure

Secondary Port Removal

Remove LIF and suprapubic ports under direct vision, ensuring no bleeding on deflating pneumoperitoneum.

Umbilical Port Closure

Close the umbilical port with J PDS or J Vicryl suture.

• insert finger into the defect, pull the suture upwards closing the defect on finger.
• Close the defect fully while ensuring no bowel is caught in the closing suture
• tie the suture to close the defect.
• inspect and feel after tying the stitch to ensure defect successfully closed

Skin Closure

Close all skin incisions with 3/0 Monocryl sutures.

Final Inspection

Perform a final check of all incision sites to ensure proper closure and hemostasis.

Hints and Tips for Successful Laparoscopic Appendectomy

Maintain Traction

Keep appropriate traction on the appendix throughout the procedure for better visualization and dissection.

Camera Flexibility

Using a 5mm laparoscopic camera allows for insertion through different ports, increasing maneuverability.

Safe Diathermy

When using the diathermy hook, dissect towards the anterior abdominal wall to avoid injuring surrounding structures if you overshoot.

Ask for Help

If not progressing, consider asking for help or converting to open procedure early, before fatigue sets in.

Pitfalls to Avoid in Laparoscopic Appendectomy

Misidentification

Ensure confident identification of the appendix to avoid removing other structures like fallopian tubes or ovaries.

Ureter Injury

Be conscious of the ureter's proximity, especially when the retroperitoneum is friable and inflamed.

Incomplete Hemostasis

Always leave a dry field to prevent postoperative complications.

Inadequate Visualization

Maintain proper camera positioning and cleaning to ensure clear view throughout the procedure.

Open Appendectomy: Patient Positioning

Patient Position

Position the patient supine, preferably with arms tucked in at the sides.

Surgeon Position

The surgeon stands on the right side of the patient.

Assistant Position

The assistant stands on the left side of the patient.

Open Appendectomy: Incision and Exposure

Incision Choice

Choose between McBurney's/Grid iron incision or Lanz incision based on surgeon preference.

• McBurney’s/Grid iron incision:
  • an incision perpendicular to the line that forms McBurney’s point.
    • how to locate
      • find Mc Burney’s line (a line between ASIS and the umbilicus).

• Find McBurney’s point (a point 1/3 from the ASIS on this line)

• Gridiron incision: Draw a line perpendicular to McBurney’s line, bisecting McBurney’s line at Mc Burney’s point.

• Lanz incision
  • a line through McBurney’s point.
  • More transverse in comparison to the Gridiron incision (try to follow the skin creases)
  • follow’s langer’s lines more closely, better. cosemsis

Layer Dissection

• Divide the subcutaneous fat and the scarpa’s fascia until you reach the external oblique aponeurosis.
• apply a self retaining retractor to free your assistant

Layers you will find will be as follows:

Muscle Splitting

Split muscle layers parallel to their fibers to minimize postoperative pain and risk of incisional hernias.

Peritoneal Entry

Enter the peritoneum carefully, watching for adherent bowel.

Dividing muscle layers

External oblique

• raise the external oblique aponeurosis with 2 mosquito clips
• open aponeurosis with a knife cutting between your mosquito clips PARALLEL TO THE MUSCLE FIBRES
  • extend the incision with tissue scissors along the length of the wound (making sure you use the full length of you incision to get as much space as you can with the available wound).

Internal oblique

• split the layer with a pair of mayo scissors PARALLEL TO MUSCLE FIBRES
• Layer is pulled apart by 2 langenbeck retractors by your assistant.

Transversalis fascia

• two mosquito clips are applied to tent the fascia upwards
• ensure no bowel is cause in the clip
• make a small cut with dissecting scissors. Extend this along the length of the incision.

Peritoneum

• preperitoneal fat is dissected and the peritoneum is held with 2 mosquito clips.
• the perioneum is lifted and a small cut is made with scissors. Extend this along the length of the wound.

Open Appendectomy: Finding and Removing the Appendix

Appendix Localization

Use the anatomical landmarks described above to locate the appendix at the base of the cecum.

Mesoappendix Dissection

• once the appendix is found, grasp it with a Babcock Forceps and deliver it through the wound.
• Dissect a window into the mesoappendix with artery clips
• ligate the appendiceal artery with 2/0 vircyl ties (or transfix with 2/0 vircyl sutures

Appendix Removal

• the base of the appendix is crushed with a large crushing clip
• unclip, move the clip distally and apply it again.
• ligate or transfix the base of the appendix with 2/0 vircyl
• divide the appendix with a blade along the proximal end of the curshing forceps in one controlled move.

Burying the appendiceal stump

• use 2/0 vicryl ties to perform a pursestring stitch at base of cecum to bury the base of the appendix into the cecum.
• this is an optional step. Different studies have found this to not make a difference in outcomes.

Open Appendectomy: Closure Method

Peritoneal Closure

Close the peritoneum with continuous 2/0 Vicryl sutures.

Muscle Approximation

Approximate muscles with loose interrupted 2/0 Vicryl sutures.

External Oblique Closure

Close the external oblique aponeurosis with continuous 2/0 Vicryl sutures.

Skin Closure

Close the skin with 3/0 Monocryl sutures or use clips if there is frank contamination.

Managing a Normal Appendix

Alternative Pathology

If another cause for abdominal pain is found, address it and consider leaving the normal appendix in place.

No Obvious Cause

If no other cause is found, it's generally advised to remove the appendix to prevent future diagnostic uncertainty.

Considerations

Weigh the risks of unnecessary surgery against the potential for future complications or diagnostic challenges.