ACUTE APPENDICITIS Definition Appendicitis is inflammation of the inner lining of the vermiform appendix that subsequently spreads to its other parts. Frequency The incidence of acute appendicitis is around 7% of the population Age Persons of any age may be affected, with highest incidence occurring between 15-30 years of age. Sex Before puberty  and  after 30yrs - M=F incidence Teenagers & young adults - M:F - 3:2(slight male predominance)  Relevant Anatomy The appendix is a wormlike extension of the cecum, and its average length is 8-10cm (ranging from 2-20 cm). This organ appears during the fifth month of gestation, and its wall has an inner mucosal layer, 2 muscular layers, and a serosa. Several lymphoid follicles are scattered in its mucosa. The number of follicles increases when individuals are aged 8-20 years. The inner muscular layer is circular, and the outer layer is longitudinal and derives from the taenia coli. Taenia coli converge on the posteromedial area of the cecum. This site is the appendiceal base. The appendix runs into a serosal sheet of the peritoneum called the mesoappendix. Within the mesoappendix courses the appendicular artery, which is derived from the ileocolic artery. Sometimes, an accessory appendicular artery (deriving from the posterior cecal artery) may be found. The vasculature of the appendix must be addressed to avoid intraoperative hemorrhage. The position of appendix vary thus the nonspecific signs and symptoms of appendicitis. Etiology Appendicitis is caused by obstruction of the appendiceal lumen. The causes of the obstruction include: 1)       Lymphoid hyperplasia secondary to irritable bowel disease (IBD) or infections (more common during childhood and in young adults) 2)       Fecal stasis and fecaliths (more common in elderly patients) 3)       Parasites 4)       Foreign bodies 5)       Neoplasm-carcinoids, lymphoma, carcinoma of caecum. 6)       Strictures NB Lymphoid hyperplasia may also related to Crohn disease, mononucleosis, amebiasis, measles, and GI and respiratory infections. Fecaliths are solid bodies within the appendix that form after precipitation of calcium salts and undigested fiber in a matrix of dehydrated fecal material 4-Obturator sign-pain with internal rotation of flexed right thigh in pelvic appendicitis 5- Dunphy sign- Increasing pain with cough 6- Blumberg sign -Rebound tenderness related to peritoneal irritation elicited by deep palpation with quick release. When patient is on moving trolley patient feels pain. -Retrocecal appendix-flank tenderness in RLQ Auscultation Bowel sounds-may absent in perforated appendix-paralytic ileus.May be increased in appendicitis associated with obstruction at caecum DRE Pelvic appendix-anterior and suprapubic pain on rectal exam. Blood in examining finger NB Signs of peritoneal inflammation in the right iliac fosse are often absent in the early stages of the illness. The patient should be asked to cough, blow the abdominal wall out and draw it in; all of these cause pain if the parietal peritoneum is inflamed Pathology Gross:In the early stages of the disease, the appendix grossly appears edematous with dilation of the serosal vessels As time passes, the appendiceal wall grossly appears thickened, the lumen appears dilated, and a serosal exudate (fibrinous or fibrinopurulent) may be observed as granular roughening. Micro: neutrophil infiltrate of the mucosal and muscularis layers extending into the lumen Investigations Usually a clinical diagnosis, investigations more useful in atypical presentations to rule out other differentials and confirm the diagnosis Laboratory 1.FHG A mild elevation of WBCs (ie, >12,000/mL) is a common finding in patients with acute appendicitis especially neutrophilia.Values greater than 17,000 cells indicate complicated appendicitis. Otherwise, the WBC count has low specificity. 2.Urinalysis Differentiating appendicitis from urinary tract conditions. Mild pyuria may occur in patients with appendicitis because of the relationship of the appendix with the right ureter. Severe pyuria is a more common finding in UTI. Hematuria  in ureteric colic. Glycosuria in Diabetic ketoacidosis Urobilinogen in acute porphyria 3.U/E/C Detect any deranged electrolytes- Vomiting, diarrhea and anorexia. Correction done. Renal Pyelonephritis and colic R/o 3.C-reactive protein and ESR C-reactive protein (CRP) has been reported to be useful in the diagnosis of appendicitis. This protein is physiologically produced by the liver when bacterial infections occur and rapidly increases within the first 12 hours 4.Liver and pancreatic function tests (eg, Transaminases, bilirubin, alkaline phosphatase, serum lipase, amylase) R/o Acute pancreatitis and cholecystitis 5.Pregnacy test-in females of childbearing age MANAGEMENT Supportive 1.Analgesics-diclofenac 2.NG tube 5.Maintenance fluids and correction of electrolytes 4. Pre-op antibiotics broad spectrum antibiotic; cefoxitin, cefotetan plus Metrodidazole. Gangrenous or perforating appendicitis - broadened antibiotic coverage for aerobic and anaerobic enteric pathogen. Definitive -Immediate appendectomy; open or laparoscopic. -Drainage of abscess, if present Open appendectomy -Prior to incision, the surgeon should carefully perform a physical examination of the abdomen to detect any mass and to determine the site of the incision Incisions a) Gridiron Centred on McBurney's point perpendicular  to line joining ASIS & umbilicus.Difficult to extend, more difficult to close & provides poorer access to the pelvis & peritoneal cavity b)Lanz incision (Transverse or skin crease incision)  Centred on midclavicular 2cm below the umbilicus. ** Exposure is better & extension when  needed is easier especially when the  diagnosis is in doubt, particularly in the presence of intestinal obstruction C) Rutherford Morison's incision Useful if the appendix is para- or retrocaecal & fixed It is possible to convert the Gridiron incision to a Rutherford Morison by cutting the internal oblique & transversus muscles in the line of the incision) Laparoscopic appendisectomy -3 cannulae are placed during the procedure. -Two of them have a fixed position (ie, umbilical and suprapubic). -The third is placed in the right periumbilical region position may vary. -Umbilical incision for  placement of a Hasson cannula or Veress needle -Pneumoperitoneum (10-14 mm Hg) is established and maintained by insufflating carbon dioxide. -Through the access, a laparoscope is inserted to view the entire abdomen cavity. -Trocar is introduced suprapubic  allow the introduction of instruments (eg, incisors, forceps, stapler). -Another trocar is placed in the right periumbilical for insertion of an atraumatic grasper to expose the appendix. - The appendix may be removed through the umbilical or the suprapubic cannula using a laparoscopic pouch to prevent wound contamination. - Peritoneal irrigation is performed with antibiotic or saline solution Advantages 1.Decreased postoperative pain 2.Shorter time to return to usual activities 3.Lower incidence of wound infections or dehiscence. This procedure is cost effective but may require more operative time compared with open appendectomy

Pathophysiology -Independent of the etiology, obstruction causes an increase in pressure within the lumen due to continuous secretion of fluids and mucus from the mucosa and the stagnation of this material. At the same time, intestinal bacteria within the appendix multiply, leading to the recruitment of white cells and the formation of pus and even higher intraluminal pressure. -If appendiceal obstruction persists, intraluminal pressure rises ultimately above that of the appendiceal veins, leading to venous outflow obstruction. As a consequence, appendiceal wall ischemia begins, resulting in a loss of epithelial integrity and allowing bacterial invasion of the appendiceal wall. -Various specific bacteria, viruses, fungi, and parasites can be responsible agents of infection that affect the appendix, including Gram - bacilli, Viruses-adenovirus, cytomegalovirus, actinomycosis, Mycobacteria species, Histoplasma species, Schistosoma species, pinworms, and Strongyloides stercoralis -Uncorrected this leads to gangrene and perforation of the appendix. As this process continues, a peri appendicular abscess or peritonitis may occur. -In neonates (due to a poorly developed omentum), the elderly (omentum shrinks in size) & the immunocompromised , the condition is not controlled lead free bacterial contamination of the peritoneal cavity and generalised peritonitis. -In the rest, the greater omentum & loops of small bowel become adherent to the inflamed appendix, walling off the spread of peritoneal contamination, resulting in a phlegmonous mass & eventually may form a paracaecal abscess. Rarely appendiceal inflammation resolves leaving a distended mucous-filled organ - mucocele of the appendix. Symptoms 1) Abdominal pain (100%) - periumbilical then right-lower-quadrant (RLQ). Pain lessened with flexion at the hip. 2) Anorexia (almost 100%) 3) Nausea (90%) 4) Vomiting (75%)-mild 5) Obstipation-inability to pas stool and flatus 6) Diarrhea-mild 7)Appendix next to bladder or ureter, inflammation may cause urinary symptoms of frequency, dysuria and (microscopic) pyuria Physical examination -Vitals-fever and tachycardia -Dehydration Do full abdominal examination and DRE Inspection Complicated appendix-movement with respiration may be absent, distension of the abdomen Palpation -Maximal tenderness at "McBurney's point" 2/3 distance from umbilicus to Anterior superior iliac spine -RLQ tenderness and rebound tenderness -Voluntary contraction (guarding ) -Involuntary contraction (rigidity) Signs include: 1-Pointing sign  patient may localize a region in the RLQ where pain is maximal.(parietal peritoneum irritation) 2-Raving’s sign - RLQ pain with palpatory pressure in LLQ 3-Psoas sign-pain with right thigh extension in  retroperitoneal or retrocecal appendicitis Imaging Used in differential diagnosis and to detect complications. 1 .Abdomianl x-ray: gas-filled appendix; radiopaque  fecalith or ureteric calculi; deformed cecum; air-fluid levels a perforated appendix may allow sufficient free gas to escape to be revealed on plain X-rays 2. Barium enema-non-filling appendix; RLQ mass effect 3. Ultrasound-distended and thick walled appendix. -Non distendable appendix. -Using U/S probe to press appendix causes tenderness -Up to 90% sensitive and 95% specific for appendicitis -Rule out other differentials as ectopic pregnancy, pelvic abscess, endometriosis, ureteric colic     inflamed gall bladder 4. CT scan for peri- appendiceal abscess and wall of appendix .May be used in obese patients where ultrasonography may be hampered 5. Diagnostic laparoscopy Convergence of teniae coli is detected at the base of the appendix, beneath the Bauhin valve (ie, the ileocecal valve. Can be converted to therapeutic by doing laparoscopic appendisectomy. DIAGNOSIS OF ACUTE APPENDICITIS SCORING SYSTEM(ALVARADO Scoring system(MANTRELS)   Symptom                                       Score         Migratory abdominal pain         1         Anorexia                                     1         Nausea                                        1   Sign          Tenderness                                 2           Rebound tenderness                  1           Elevated Temperature               1   Lab. Finding          Leukocytosis                             2          Shift to the left                           1 Maximum                                          10          A score of ≥7 is strongly predictive of acute appendicitis Staging Appendicitis usually has 3 stages. 1.Edematous stage Appendicitis may have spontaneous regression or may evolve to the second stage.The mesoappendix is commonly involved with inflammation. 2.Purulent (phlegmonous) stage Spontaneous regression rarely occurs. Appendicitis usually evolves beyond perforation and rupture.Peritonitis may be possible. 3.Gangrenous stage Spontaneous regression never occurs. Peritonitis is present Procedure Incision go through the following layers                           Skin                               ↓                         Pad of fat                               ↓ Superficial fascia-Scarpa and campas fascia                                ↓ Subcutaneous tissue - an arterial twig from the superficial circumflex iliac artery usually requires ligation ↓ External oblique - cut along the line of the incision ↓ Internal oblique - split ↓ Transverse Abdominis – split                  ↓ Fascia transvasalis                  ↓ Pre-peritoneal pad of fat ↓                       Peritoneum -Character of any peritoneal fluid is noted; if purulent, collected for M/C/S. -Retractors are gently placed into the peritoneum. -The cecum is identified exteriorized by a moist gauze sponge or Babcock clamp - Appendix is identified by following the taenia coli until their convergence at base of caecum.  -Mesoappendix is held between clamps, divided, and ligated. -The appendix is clamped proximally about 5 mm above the cecum to avoid contamination of the peritoneal cavity and is cut above the clamp by a scalpel. -The appendix stump may be inverted into the cecum with the use of a purse string  suture or z-stitch -The cecum is placed back into the abdomen. The abdomen is irrigated. When evidence of free perforation exists, peritoneal lavage with several liters of warm saline is recommended. -The use of a drain is not commonly required in patients with acute appendicitis, but obvious abscess with gross contamination requires drainage. -The wound closure begins by closing the peritoneum with a running suture. Then, fascial layers are reapproximated and closed with a continuous or interrupted absorbable suture. Lastly, the skin is closed with subcutaneous sutures. NB. Incase of normal appendix, other causes of the differentials ruled out, including ovarian pathology, Meckel diverticulum, sigmoid disease, and cholecystitis. Regardless of the findings, appendectomy should be performed.  This because the patient will have a RLQ incision and in case of another acute abdomen acute appendicitis may not be considered. Differential diagnosis Pancreatico-Biliary             -Cholecystitis            - Biliary colic            - Pancreatitis GIT    - Gastroenteritis, enterocolitis - Meckel diverticulitis - Perforated duodenal ulcer            - Crohn disease, ulcerative colotis            - Colon carcinoma, peri caecal abscess            -Intussusception             -mesenteric adenitis Urinary system             -Ureteric colic             -Urinary tract infection (UTI).             -pyelonephritis Reproductive In women  -ovarian cyst torsion  -Mittelschmerz  -ectopic pregnancy  -Pelvic inflammatory disease (PID).  -Endometriosis -Saplpingitis Respiratory-Lobar pneumonia POSSIBLE COMPLICATIONS: · Wound infection · Intra-abdominal abscess, sometimes diaphragmatic · Fecal fistula · Intestinal obstruction · Incisional hernia · Liver abscess (rare) · Peritonitis with paralytic ileus