Acute Appendicitis

Take home points Appendicitis is common- 7-9% lifetime

risk Delay in diagnosis/management causes

significant morbidity- can be a surgical emergency

Usually clinical diagnosis- not reliant on imaging

Has classic presentation but often presents atypically- it is a common pitfall!

What is appendicitis? Who gets it?

Appendicitis = Inflammation of the appendix. Obstruction of opening distention perforation Mostly young people (age 10-20) but can present

at any age M>F (1.4:1) Common – 7-9% lifetime risk

Relevant Anatomy1. Where is the appendix? What is it

attached to?2. Where is McBurney’s point and what is

it?3. What places can the appendix hide?4. What nerve root (roughly) supplies the

appendix and where does it refer visceral pain to?

5. What are some other things near the appendix?

6. What organs cause R sided abdo pain?7. What organs cause lower abdo pain?

costal margin

umbilicus

ASIS

Pubicsymphisis

Relevant Anatomy1. The Appendix is…

Here!

Transverse colon

Asc. colon

Desc. colon

Sigmoid colon

Terminal Ileum

Caecum

2. McBurney’s Point

ASIS

Relevant Anatomy3. Places the appendix can hide…

… and during pregnancy

Relevant Anatomy

costal

margin

umbilicus

ASIS

Pubicsymphisis

T6

T10

T12

unpaired

Paired organs

4. Innervation of appendix & other organs

Foregut(inc. duodenum)

Midgut(inc. appendix)

HindgutLower urinary tract

Sexual organs

Relevant Anatomy5. Structures near the appendix

• Caecum• Ileum• Ureter• Ovary• Bladder• Asc Colon• Psoas• Inguinal canal• Iliac vessels

6. R abdominal pain

7. Pelvic/lower abdo pain

“Typical” Presentation Dull, crampy central abdo pain Malaise/vomiting/anorexia/low grade

fevers Pain worsens & localises to RIF with

cough/movement tenderness Systemic symptoms

Early Appendicitis

Pain: Location: Periumbilical (T10) Character: Dull Over time: Colicky Associated symptoms:

Vomiting Anorexia

obstruction

mucu

s

distention

Later Appendicitis Pain:

Location: R Iliac Fossa Character: Localised Over time: Constant Aggravating: going over bumps, coughing,

walking Relieving: hip flexion, staying still

Exam findings: “peritonism”

Guarding rebound tenderness percussion tenderness

Rovsing, psoas, other signs

Distention causingischaemia

Localised peritonealinflammation

Late Appendicitis Pain:

Location: lower abdominal/generalised Character: diffuse, severe Over time: constant Aggravating: movement, coughing, palpation,

rebound Associated: Fever

Exam findings: Systemic features- fever, tachycardia, hypotension Abdominal – severe, generalised “peritonism” RIF mass (sometimes)

Gangrene

Time Course

Appendiceal obstruction/early appendicitis – visceral peritoneal irritation

• Periumbilical colicky pain

Appendiceal distension

• Anorexia, vomiting, malaise

Irritation of parietal peritoneum (localised)

•Constant RIF pain, pain on coughing, going over bumps etc

Perforation, localised/generalised peritonitis, mass

•Fever/Sepsis

Special Clinical signs Abdominal examination Psoas Sign – pain on hip extension Rovsing Sign – RIF pain on palpating LIF “The walk” – walk with R hip

flexed, bent over Pain on coughing/unable to cough

Atypical presentationsLocation of appendix

Signs/symptoms

McBurney’s point “typical” presentation, Rovsig sign

Retro/paracaecal Psoas sign/flank pain/absence of peritonism

Retro/paraileal Diarrhoea, crampy pain

Pelvic Suprapubic pain, urinary frequency, pyuria

Complications Rupture and sepsis Periappendiceal Abscess Death

Clinching the diagnosis Appendicitis is usually a clinical

diagnosis- ie history + examination. However sometimes you’re just not

sure! All those ovaries, fallopian tubes, ureters, atypical presentations…

…perhaps you could order some tests?

What to order?1. What things could support your

diagnosis? ie inflamed/infected/obstructed

appendix

2. What things could rule in or rule out other diagnoses?

Diagnostic scoring Alvarado score

RIF tenderness +2 Increased WCC +2 Pain that migrates to

RIF +1 Rebound tenderness +1 Anorexia +1 Nausea/Vomiting +1 Fever +1 WCC- ‘left shift’ +1

1-4: Very unlikely 5-6: Possible 7-8: Very probable 9-10: Definite

What to order?1. What things could support your

diagnosis ie inflamed/infected/obstructed

appendix

2. What things could rule out other diagnoses

Ie gastro, sbo, ovarian problems, PID, UTI, renal colic, diverticulitis, crohn’s ectopic etc etc

Differential Diagnosis GI tract - asc colon,

caecum, ileum Infectious

gastroenteritis Mesenteric adenitis

(post-viral) R sided diverticulitis

(inc Meckel’s) Crohn’s/IBD Tumour SBO herniae

Urinary tract – ureters, bladder UTI Renal/ureteric colic

Female reproductive tract- ovaries, tubes Mittelschmerz PID Cyst rupture Torted cyst/tube Ectopic pregnancy

Weird/wonderful Musculoskeletal Shingles

Pathology/Lab investigations White cell count (WCC) – usually mildly

elevated, around 11-14,000 C reactive protein (CRP) – also elevated

Urinalysis sometimes positive for blood, leuks; not very helpful in discriminating vs UTI

Electrolytes, renal function, haemoglobin, platelets, liver function, coagulation should all be normal unless profoundly unwell- if abnormal think of other things.

Imaging CT

Good for getting an overview of all the structures esp bowel

Accurate- sensitive and specific >90% Less good at pelvic anatomy than abdo anatomy Radiation exposure

Ultrasound Good at visualising tubular structures & cysts Not as accurate as CT (sens 70%, spec 90%),

sometimes difficult to see appendix Good if you need to rule out things like ectopic or

ovarian pathology

Diagnostic Laparoscopy Safe Useful for when diagnosis is unclear Esp in females w/ suspected gynae

pathology (eg PCOS/endometriosis/menstruating/ovulating)

Management1. Supportive and symptomatic

managementAntibiotics/fluids/etc

2. Treatment of underlying causeAppendicectomy

What to do in ED/awaiting surgery Resuscitation!

A: ensure airway patent B: ensure adequate oxygenation C: correct

hypotension/tachycardia/instability

Septic shock Systemic inflammatory response- usual

appropriate local responses make no sense when systemic Generalised vasodilation (flushing), capillary leak-

fluid leaves central circulation Hypotension, tachycardia- organs not perfused

properly Either fever or hypothermia Other complications like

coagulopathy/DIC/multiorgan failure ARDS in severe sepsis- hypoxia

Treatment of infection, sepsis Antibiotics- in appendicitis cover gram negs

(gentamicin/ceftriaxone), enterococcus (ampicillin/vancomycin), anaerobes (metronidazole)

Drain pus, remove infected material Replace fluid that is lost peripherally – IV

cannula, fluid resuscitation Blood tests, imaging, other tests- find source Correct other organ dysfunction If necessary ICU and advanced life support

Procedures Appendicectomy

Laparoscopic Open

Diagnostic laparoscopy Laparotomy

Appendicectomy - Laparoscopic “Keyhole” surgery Lower complication rate, quicker recovery Sometimes difficulty in mobilisation

requiring open procedure

Appendicectomy - Open Incision over McBurney’s point or point of

maximal tenderness Straightforward, good exposure, technically

easier Longer recovery, risk of hernia & adhesions, can’t

see pelvic structures as well

Summary Careful history & examination is very

important! Principles of treatment- operation,

antibiotics, supportive care Early diagnosis & management (ie

surgical r/v) is crucial Many pitfalls in dx