03. appendicitis dr phillip bmc
TRANSCRIPT
APPENDICITIS
Dr Phillipo Leo ChalyaM.D. (Dar); M.Med Surg (Mak)
Specialist surgeon - Bugando Medical Centre
FORMAT Definition A historical perspective Epidemiology Aetiology Classification Pathophysiology Clinical presentation Differential Diagnosis Work up Treatment Complications
DEFINITION Appendicitis refers to inflammation of
the vermix appendix
A HISTORICAL PERSPECTIVE
First described by Reginald Fitz in 1886 who also was the first to advocate appendicectomy as the cure
In 1889 Charles McBurney described the clinical findings of acute appendicitis including the point of maximum tenderness in RIF which bears his name
EPIDEMIOLOGY
Incidence: The incidence is higher in developed
countries and in developing countries which are adopting a more refined western type diet
Incidence of appendicitis is lower in cultures with a higher intake of dietary fiber
EPIDEMIOLOGY [cont’d] Mortality/Morbidity:
The overall mortality rate of 0.2-0.8% is attributable to complications of the disease rather than to surgical intervention
Mortality rate rises above 20% in patients older than 70 years, primarily because of diagnostic and therapeutic delay
Perforation rate is higher among patients younger than 18 years and patients older than 50 years, possibly because of delays in diagnosis
Appendiceal perforation is associated with an increase in morbidity and mortality rates
EPIDEMIOLOGY [cont’d] Sex:
The incidence of appendicitis is approximately 1.4 times greater in men than in women
The incidence of primary appendectomy is approximately equal in both sexes
EPIDEMIOLOGY [cont’d] Age:
Appendicitis may occur at all ages, but is most commonly seen in the 2nd and 3rd decades of life
The incidence of appendicitis gradually rises from birth, peaks in the late teen years, and gradually declines in the geriatric years
Although rare, neonatal and even prenatal appendicitis have been reported in literature
The emergency physician must maintain a high index of suspicion in all age groups
AETIOLOGY
Etiological factors for appendicitis include:- Appendiceal luminal obstruction Diet Social status Familial susceptibility
Appendiceal luminal obstruction Luminal causes
Feacolith Lymphoid follicle hyperplasia Worms e.g. ascaris Foreign body
In the wall Stricture Neoplasms
Outside the wall Adhesions kinks
Diet
Low intake of dietary fiber is associated with increased incidence of appendicitis
Dietary fiber is thought to decrease the viscosity of feces, decrease bowel transit time, and discourage formation of fecaliths that predispose individuals to obstructions of the appendiceal lumen
Familial tendency
Appendicitis tends to run in certain families may be due to peculiar position of the organ which predisposes to infection
CLASSIFICATION
Clinical classification Pathological classification
Clinical classification
Acute appendicitis Subacute appendicitis Recurrent appendicitis Chronic appendicitis
Pathological classification
Obstructive appendicitis Non-obstructive appendicitis
PATHOPHYSIOLOGY
Two types:- Obstructive appendictis Non-obstructive appendicitis
Obstructive appendicitis Luminal obstruction and mucus production
result in increased intraluminal pressure Bacteria trapped within the appendiceal
lumen begin to multiply, and the appendix becomes distended
Luminal distention stimulates visceral nerve endings concerned with pain [visceral pain]
This produce dull aching pain felt periumbilically according to nerve supply of the appendix (T10) referred pain
Venous congestion and edema follow next, and by 12 hours after onset, the inflammatory process may become transmural
Obstructive appendicitis[ cont]
Peritoneal irritation then develops If the obstruction is left untreated,
arterial blood flow to the appendix is compromised, and this leads to tissue ischemia and necrosis
This stimulates parietal nerve endings shift of pain to the RIF
Full thickness necrosis of the appendiceal wall leads to perforation with the release of fecal and suppurative contents into the peritoneal cavity
Obstructive appendicitis [cont] Depending on the duration of the
disease process, either a localized walled-off abscess or mass occurs, or if the pathologic process has advanced rapidly, the perforation is free in the peritoneal cavity and generalized peritonitis occurs
The commonest bacterial growth from inflamed appendices include Escherichia coli, Kleblesiella spp., Proteus spp and Bacteroids
Non-obstructive appendicitis This is less dangerous type
Inflammation commences in the mucous membrane or in the lymphoid follicles and gradually spread to the submucosa
As there is no obstruction there is not much distension, but when the serosa is involved localizing peritonitis develops and the patient c/o RIF pain
Such inflammation terminates either by:- Suppuration Gangrene Fibrosis Resolution
Many of the sub-acute appendicitis, recurrent appendicitis and chronic appendicitis develop from this variety
CLINICAL PRESENTATION
History: classic symptoms include:- Periumbilical pain [visceral pain] which
shifts and localize to the RIF [parietal or somatic pain]
Periumbilical pain is colicky in nature in obstructive type and is dull aching and constant in non-obstructive type
RIF pain is sharp intense and well localized to the RIF
Anorexia Nausea & Vomiting
CLINICAL PRESENTATION [cont’d]
Physical examination Pyrexia RIF tenderness Muscle guarding Rebound tenderness Special test to elicit in appendicitis
Pointing sign Rovsing’s sign [RIF pain with palpation of the
LIF ] Psoas sign [RIF tenderness with internal rotation
of the flexed right hip] Obtrurator sign [RLQ pain with hyperextension of
the right hip ]
DIFFERENTIAL DIAGNOSIS
Abdominal disorders Gynecological disorders Retroperitoneal disorders Thoracic disorders Others
Abdominal disorders
Acute cholecytitis Perforated peptic ulcers Entecolitis Intestinal obstruction Carcinoma caecum Crohn’s diseases Amoebic colitis Meckel’s diverticulitis Acute pancreatis
Gynecological disorders
PID Ectopic pregnancy ® Twisted ovarian cyst ® Ruptured ovarian follicles ®
Retroperitoneal disorders
Right ureteric colic Right sided acute pyelonephritis Right sided testicular torsion Retroperitoneal haematoma
Thoracic disorders
Basal pneumonia Pleurisy
Miscellaneous
Henoch-Schoenlein purpura Porphyria Diabetic abdomen
WORK UP
Lab investigations Complete blood cell count
Leucocytosis Neutrophilia greater than 75%
C-reactive protein test Urinalysis
WORK UP [cont’d] Imaging investigations
Abdominal radiography The kidneys-ureters-bladder (KUB) view is
typically used Visualization of an appendicolith in a patient
with symptoms consistent with appendicitis is highly suggestive of appendicitis, but this occurs in fewer than 10% of cases
The consensus in the literature is that plain radiographs are insensitive, nonspecific, and is not cost-effective
WORK UP [cont’d]
Abdominal Ultrasonography An outer diameter of greater than 6 mm,
noncompressibility, lack of peristalsis, or periappendiceal fluid collection characterizes an inflamed appendix
The normal appendix is not visualized It’s noninvasive, short acquisition time,
lack of radiation exposure, and potential for diagnosis of other causes of abdominal pain, particularly in the subset of women of childbearing age
However it is operator dependent
WORK UP [cont’d] Computed tomography
Abdominal CT has become the most important imaging study in the evaluation of patients with atypical presentations of appendicitis
Advantages of CT scanning include Sensitivity and accuracy compared with those of
other imaging techniques Readily available Noninvasive potential to reveal alternative diagnoses
Disadvantages lengthy acquisition time if oral contrast is used patient discomfort if rectal contrast is used Exposure to radiation
It is really required to make diagnosis of acute appendicitis
DIAGNOSTIC SCORING SYSTEM
Various scoring systems have been devised to aid diagnosis of appendicitis
Although many diagnostic scores have been advocated, most are complex and difficult to implement in the clinical situation
The Alvarado score, is a simple scoring system that can be instituted easily
The Classic Alvarado score [1986] is based on three symptoms, three signs and two laboratory findings and has a total score of 10
Classic Alvarado Score [1986]Features Score
Symptoms Migratory RIF pain 1 Anorexia 1 Nausea & vomiting 1Signs Pyrexia 1 Tenderness RIF 1 Rebound tenderness RIF 2Lab investigations Leucocytosis 2 left shift of neutrophil maturation 1
Total 10
Diagnostic Scoring System [cont]
Kalan et al [1994] omitted one lab parameter [left shift of neutrophil maturation] which is not routinely available in many laboratories, and produced a modified score which have only one lab findings
A modified Alvarado score [1994] is based on three symptoms, three signs and one laboratory findings [total score of 9]
MAS is commonly used
Modified Alvarado Score [1994]Features Score
SymptomsMigratory RIF painAnorexiaNausea & vomiting
111
SignsPyrexia Tenderness RIFRebound tenderness RIF
Lab investigationleucocytosis
112
2
Total 9
MASS- interpretation
A score of 1-4:[ discharging group] The diagnosis of acute appendicitis is unlikely
A score of 5-6: [observing group] Probable to have appendicitis but not convincing to have urgent appendicectomy
A score of 7-9: [emergency group] Regarded as probable to have acute appendicitis and needs emergency appendicectomy
TREATMENT
The treatment of appendicitis is appendicectomy
Appendicectomy can be elective, emergency or interval
Two types of appendicectomy:- Conventional open appendicectomy Laparoscopic appendicectomy
Preoperative care
Iv fluid Analgesics Preoperative antibiotics with broad
spectrum antibiotics Check Hb, blood grouping and
crossmatching Shaving Written informed consent Pre-anaesthetic visit
Intraoperative care
Open appendicectomy Incisions
Grid-iron sss Rurtherford Morrison’s Lanz’s [transverse skin crease] SUMI when the diagnosis is not clear Rt lower paramedian Midline incision
Intraoperative care cont’d Appendiceal locations of the tip
Retrocaecal appendix [70%] Pelvic appendix [25%]- the tip hangs in the pelvic brim Subcaecal appendix [2%] Splenic appendix [1%]- either pre- or post-ileal i.e
anterior or posterior to the terminal ileum Paracaecal appendix [1%] Paracolic appendix [1%]-either to the right or left of
ascending colon, the tip in the extraperitoneal tissue Location of the base-is constant, being found at
confluence of 3 taeniae coli of the caecum which fuse to form the outer longitudinal muscle coat of the appendix
Post operative care
Iv fluids Analgesics Antibiotics Monitor- Vital signs Discharge home in 2-3 days
postoperatively
COMPLICATIONS
Complications of acute appendicitis Postoperative complications
i. Complications of acute appendicitis
Appendicular mass Appendicular abscess Recurrent appendicitis Perforation peritonitis
Treatment of complications
Appendicular abscess Appendicular mass Peritonitis Recurrent appendicitis
a.Appendicular mass
Use conservative Ochsner-Sherren regime Iv fluid NGT Analgesics Antibiotics –parenteral Mark the limits of the mass on the
abdominal wall using a skin pencil Monitor- vital sign, size of the mass,
input/output chart Clinical improvement is expected in 24-
48 hours
Appendicular mass [cont]
Criteria for stoping OSR Increased pulse rate Increasing or spreading abdominal
pain Increasing the size of the mass Vomiting or increasing gastric
contents
b.Appendicular Abscess
I & D Antibiotics
c.Recurrent appendicitis
Elective appendicectomy
ii.Postoperative complications Wound infections
Intrabdominal abscess Paralytic ileus Feacal fistula Adhesive intestinal obstruction Portal pyaemia due to septicemia in the
portal venous system Respiratory complications DVT embolism RIH due to damage to iliopogastric /
ilioinguinal nerves Incisional hernia