Acute appendicitis

Surgery,pathogenesis, diagnosis, ALVORADO, TZANAKIS, PAS, scores. Per-op surgical issues and differential diagnosis

1. ACUTE APPENDICITIS Resident: Dr SD Sanyal Moderator: Brig SR Ghosh Consultant Surgery and GI Surgeon

2. Introduction Vestigeal organ Surgical importance: Propensity for inflammation Most important cause of “Acute Abdomen” in young adults

3. Anatomy Present only in humans At birth: Short & broad at its jn with the Caecum Typical tubular structure produced by 02 years of age Results from differential growth of caecum

4. Anatomy Position: constant  a t the confluence of the 03 taenia coli of caecum Mesoappendix : Arises from the lower surface of the mesentery of terminal ileum Appendicular Artery: Branch of Ileo -colic artery – End Artery 04-06 Lymphatic channels traverse Mesoappendix ----------> Ileo-caecal LNs

5. Microscopic anatomy Layers: - Mucosa - Submucosa - Muscularis - Serosa

6. Microscopic anatomy Lumen has longitudinal folds of mucous membrane Lining: Columnar cells of colonic type Crypts: Argentaffin ( Kulchitsky cells ) Submucosa : Lymphatic aggregations/Follicles

7. Anatomical Positions RETROCAECAL 74% PELVIC 21% PARACAECAL 2% SUBCAECAL 1.5% PREILEAL 1% POSTILEAL 0.5%

8. Anatomical positions

9. Etiology Low dietary fibre Faecoliths Stricture Worm infestations: Oxyuris vermicularis Neoplasms : Ca caecum , carcinoids Viral

10. Pathology Lymphatic hyperplasia Luminal obstruction Increased intra-luminal pressure Edema , mucosal ulceration Bacterial translocation to submucosa

11. Pathology Resolution Venous obstruction Ischaemia of appendix wall Invasion of muscularis propria , submucosa

12. Pathology Acute Appendicitis Lump/ mucocele Gangrenous appendicitis Peritonitis

13. Bacteriology of perforated appendicitis TYPE OF BACTERIA PATIENTS (%) ANAEROBIC B. fragilis 80 B. thetiaotaomicron 61 Bilophila wadsworthia 55 Peptostrptococcus spp 46 AEROBIC E.coli 77 S.viridans 43 Group D streptococcus 27 P.aeruginosa 18

14. Clinical features Symptoms: Periumbilical pain 50% cases Pain shifts to RIF Anorexia Nausea/vomiting

15. Clinical features Signs: Pyrexia Localized tenderness in RIF Muscle guarding Rebound tenderness Rovsing’s sign Pointing sign Psoas sign Obturator sign

16. Clinical features Risk factors for perforation: Extremes of age Immunosuppression Diabetes mellitus Pelvic appendix Previous abdominal surgery

17. Special clinical scenarios According to position: Retro- caecal - Silent appendix - Quadratus lumborum rigidity - Psoas sign - Loin tenderness

18. Special clinical scenarios 2. Pelvic - Early diarhoea - Increased urinary frequency - Deep tenderness over symphysis pubis - DRE: Rectovesical pouch/POD tenderness - Obturator / Psoas sign + ve

19. Special clinical scenarios 3. Post- ileal - Diarrhoea - Marked retching - Ill defined tenderness to rt of umbilicus

20. Special clinical scenarios As per age: Infants - Uncommon <36 mths - Difficult to diagnose - Diffuse peritonitis common - High incidence of perforation

21. Special clinical scenarios 2. Children - Vomiting - Marked anorexia 3. Elderly - High incidence of gangrene & perforation - Features of SAIO 4. Obese - Diminished signs/ delayed dignosis - Midline/ Laparoscopic approach

22. Special clinical scenarios 5. Pregnancy - Most common extra-uterine cause of acute abdomen - Delayed presentation - Fetal loss 3-5% Upto 20% : Perforation

23. Differential Diagnosis Children - Gastroenteritis - Mesenteric adenitis - Meckel’s diverticulitis - Intussusception - HS purpura - Lobar pneumonia

24. Differential Diagnosis 2. Adults - Regional enteritis - Ureteric colic - Perforated peptic ulcer - Torsion of testis - Pancreatitis - Rectus sheath haematoma

25. Differential Diagnosis 3. Adult female - Mittelschmerz - PID - Pyelonephritis - Ectopic pregnancy - Torsion/ rupture of ovarian cyst - Endometriosis

26. Differential Diagnosis 4. Elderly - Diverticulitis - Intestinal obstruction - Ca colon - Mesenteric infarction - Torsion of appendix epiploicae - Leaking aortic aneurysm

27. Differential Diagnosis 5. Rare - Tabetic crisis - Spinal conditions - Porphyria - Diabetes - Typhilitis

28. Investigations Diagnosis is essentially clinical Clinical diagnosis alone - 15-30% negative appendicectomy Use of - Clinical scoring systems - Imaging modalities - Diagnostic Laparoscopy - Routine laboratory examinations

29. ALVORADO Score Migratory RIF pain 1 Symptoms Anorexia 1 Nausea & vomiting 1 RIF tenderness 2 Signs Rebound tenderness 1 Elevated temperature 1 Laboratory Leucocytosis 2 Shift to left 1 _______________________________________ Total 10

30. ALVORADO Score < 4: Excludes diagnosis 5-6: Equivocal >7 : Strongly s/o appendicitis Modified Alvorado Score: - 9 points - Differential count not done PAS : - Total : 10 - Rebound tenderness excluded - Cough/percussion/hopping tendeness = 2 - Leucocytosis > 10,000  1

31. Tzanakis Score 1. Rt lower abdominal tenderness = 4 2. Rebound tenderness = 3 3. WBC’s> 12,000 in the blood = 2 4. Positive USS findings of appendicitis = 6 Total score = 15 > 8 = 96% chances

32. Computed Tomography Commonly used in the West 5mm slices : - Sensitivity: 90% - Specificity: 80 – 90% RCT for 64-MDCT : 95% accuracy Sensitivity PROPORTIONATE TO Severity Faecoliths / Appendicoliths detected in 50% pts of appendicits ???

33. Computed Tomography Classical findings: - Distended appendix > 7mm diameter - Halo/ Target sign - Periappendiceal fat stranding - Edema - Peritoneal fluid - Phlegmon - Periappendiceal abscess

34. Computed Tomography Rational use: - Elderly - Atypical presentations - Neoplasms - Acute diverticulits - Intestinal obstruction MRI: ??

35. US Scans Sensitivity = 85% Operator based Specificity > 90% AP dia appendix > 7mm CROSS SECTIONAL VIEW: - Thick walled - Non compressible luminal structure : Target Lesion Periappendiceal fluid/ Mass

36. Plain Abdominal X-Rays Low sensitivity Appendicoliths picked up in only 10-15% cases Can be combined with Barium enema Failure of appendix to “Fill up” Low specificity  20% of normal Appendices do not fill up

37. Diagnostic Laparoscopy Small fraction of pts Women of child bearing age Prompt intervention ------- Implications on future fertility

38. Laboratory Examinations WBC’s elevated Normal in 10% cases TLC > 20,000 s/o PERFORATION Polymorphs > 75% Minimal pyuria Common Microscopic haematuria

39. Diagnostic algorithm Surgical consultation for acute abdomen Clinical probability of Ac appendicitis High Intermediate Low Elderly/ unreliable/ far Operate CT/USG & reassess Local/reliable

40. Diagnostic algorithm + ve Uncertain - ve Operate DL/admit Disc/alt

41. Diagnostic algorithm Elderly/unreliable/far Reliable & local CT re-examine Discharge/ follow up<24h + ve Operate - ve Discharge/follow up<24h

42. Treatment Early/simple Delayed/complicated Late Appendicectomy * Late/ recov Obese/F Others Colonoscopy Old/ Perf Interval Laparoscopic Open/Laparoscopic Appendicec

43. Treatment Adult/Non-pregnant Child/Pregnant adult CT Scan Ultrasound Simple Large abscess Phlegmon /small appendicitis abscess

44. Treatment * Antibiotics+Drainage Antibiotics Improvement No improvement Colonoscopy(adults) Open appendicectomy Laparoscopic interval appendicectomy

45. Management of Appendicular abscess/Lump Late presentation Clinically mass & fever Subject to imaging studies to ascertain: - Presence - Size > 4-6cms  Antibiotics+Drainage < 4 cms  Conservative mgt( Oschner Sherren’s Regime)

46. Management of Appendicular abscess/Lump Criteriae for stopping conservative mgt: - Rising pulse rate - Increase in the size of the mass - Increasing/ spreading abdominal pain

47. Problems Intra-operatively 1. Normal appendix – Exclude: - Meckel’s - Terminal ilietis - Tubo -ovarian causes - Perform appendicectomy in Open approach - Appendix may be left behind during laparoscopy

48. Problems Intra-operatively 2. Appendix not found: - Mobilise caecum - Taenia coli to be traced to their confluence Appendicular tumour: - <2cms: Appendicectomy - >2cms: Rt hemicolectomy

49. Complications Wound infection Intra-abdominal abscess Ileus Portal pyaemia ( pyelephlebitis ) Faecal fistula Adhesive intestinal obstruction

50. Discussion TAC test in a peripheral set-up???