Indications

Appendicitis – acute or subacute process that causes the lumen of the appendix (which is a blind sac) to become obstructed with buildup of pressure and eventual rupture.

Mass – rarely an appendiceal mass is found on CT scan or during intra-abdominal surgery (laparotomy)

Abscess – if found secondary to appendicitis it must be drained. If it is diagnosed preoperatively care currently is to have an interventional radiologist (a radiologist who does procedures) drain the abscess via a percutaneously (through the skin) placed catheter that is left in place to decompress the cavity and allow it to “heal from the inside out”. The appendix is then removed at about 6 weeks. If it is found during surgery it must be decompressed and a drain left in place in the abcess cavity by the surgeon.

Contraindications

Existing appendiceal rupture with defined abscess cavity.

Appendicitis in setting of adjacent inflammatory bowel disease (e.g., a Crohn’s disease flare-up in the contiguous terminal ileum or cecum.

Diagnosis

Clinical diagnosis – appendicitis remains a clinical diagnosis primarily. There is no set of invariably ocurring signs and symptoms. The two most common are anorexia (loss of appetite) and pain, although there are many cases of appendicitis that have neither of these. Other signs and symptoms included pain around the umbilicus that “moves” to the right lower quadrant, fever, nausea, vomiting, diarrhea, rigid and board-like abdomen, and worsening pain on walking. Appendicitis is most difficult to clinically diagnose in the very young and very old and in patients who are diabetic or on steroids.

Radiographic diagnosis – there are three radiographic studies that are commonly used to help diagnose appendicits, although in clear-cut clinical cases none is absolutely required. The most widely used is computed tomography (CT) of the abdomen and pelvis with 5 mm cuts. For best results this should be performed with intravenous dye, dye given by mouth (or PO), and dye given per rectum (although this is often not done as it is uncomfortable for the patient and radiology technician both.) Findings consistent with appendicitis are stranding in the mesentery, non-visualization of the appendix lumen, fluid in the pelvis, and an enlarged and thickened appendix, especially if it is seen in cross-section. It must be noted that a normal CT does not rule appendicitis. Studies have shown that a CT can miss appendicitis, especially in the early stages, in up to 10% of cases.

Although less widely used today, plain-film radiography (aka “a flat plate”) can be helpful in showing an opacity in the right lower quadrant that could be suggestive of an fecolith (insissipated stool in the mouth of the appendix).

The third radiology test that is sometimes used in children is an ultrasound of the right lower abdomen. This test is easy to perform, non-invasive, and has no radiation exposure, but it is of limited help as it is sometimes difficult to visualize the appendix (either normal or inflamed). It is almost never used in adults due to the larger body habitus.

Preoperative Workup and Preparation

Fluid Resuscitation – this usually consists of crystalloid fluids intravenously to restore any intravascular fluid depletion that might be present due to inflammation of the peritoneum (peritonitis) and fluid sequestration in the intraabdominal tissues (”third spacing”). The fluid given is usually normal saline solution or lactated Ringer’s solution.

Antibiotics – uniformly given. Since the appendix comes off the terminal ileum at the juncture of the colon, rupture leads to spillage into the peritoneal cavity of gram negative and anaerobic bacteria. The type antibiotics given are Unasyn and Flagyl (metronidazole) or Zosyn (pipercillin-tazobactam) or in the case of a person with a penicillin allergy ciprofloxacin and Flagyl

Incision

McBurney incision- small incision that runs diagonally on the abdominal wall in the right lower quadrant (i.e., parallel to the edge of the external oblique muscle or in the direction running from the hip bone to the pubic bone.)

Rocky-Davis incision- small incision that runs horizontally on the abdominal wall in the right lower quadrant

Midline incision- this is sometimes done is the patient is obese or if the surgeon is anticipating the need for a formal resection of the terminal ileum and cecum (i.e., if the appendix has ruptured at the base)

Surgical Details of Procedure

1. Skin incision is made with a knife.

2. Bovie electrocautery is used to dissect through subcutaneous tissue and control small skin bleeding.

3. The aponeurosis (muscle sheath) of the outer layer of the external oblique muscle is visualized and split by a small incision with a knife and then further opened along the direction of the fibers with a scissors or the Bovie.

4. The muscle belly of the external oblique is then bluntly retracted (but not cut) using the classic muscle splitting technique via a hemostat or Kelly clamp until the aponeurosis of the internal oblique is visualized.

5. The aponeurosis of the internal oblique is split in a similar manner as the external oblique.

6. The muscle belly of the internal oblique is bluntly retracted in a similar manner as the external oblique until the peritoneum is visualized.

7. The peritoneum is grasped on either side by two forceps, pulled up and into the wound, and palpated to insure there is no bowel caught in the fold of the peritoneum.

8. The peritoneum is opened with a small incision using either a knife or scissors.

9. The peritoneal fluid is immediately inspected for amount and prurulence and cultures are taken.

10. The opening in the peritoneum is widened and two hand-held retractors are placed to expose the cecal area.

11. Manual and visual exploration for the appendix is performed by locating the convergence of the cecum and the terminal ileum.

12. The appendix is delivered up into the wound either by digitally “flipping it up” or be grasping the base with a Alice or Babcock and applying traction to allow dissection of any adhesions holding it in the abdominal cavity.

13. The entire appendix is inspected with close attention to the base to insure that the area of rupture is sufficiently distant from the base to allow a margin of healthy tissue.

14. If the base of the appendix is involved in the rupture a limited right hemicolectomy is done (see right hemicolectomy).

15. If the base of the appendix is not involved, the mesoappendix or mesentery of the appendix is divided, cross-clamped with Kelly clamps or hemostats and tied with 2-0 or 3-0 silk usually.

16. When the appendix has been isolated from the mesoappendix, the appendix proximal to the rupture is crushed with a straight clamp.

17. Two chromic ties are then placed on the area of crushed appendix.

18. The appendix is then resected off the stump distal to the ties using a knife.

19. The exposed mucosa is then ablated by the Bovie cautery.

20. Some surgeons then prefer to “dunk” the tied-off appendiceal stump by placing a running pursestring suture around the stump.

21. The intraabdominal area is inspected for bleeding and pockets of remaining infection.

22. Most surgeons will irrigate the abdominal cavity with saline solution or antibiotic-containing saline solution.

23. The edges of the peritoeum are reapproximated using a running 3-0 or 4-0 Vicryl suture.

24. The edges of the internal oblique aponeurosis are reapproximated using a 1-0 or 2-0 Vicryl suture.

25. The edges of the external oblique aponeurosis are likewise reapproximated.

26. The superficial wound is irrigated.

27. If the appendix has ruptured and there was frank pus, many surgeons will leave the subcutaneous tissue and skin open to heal by secondary intention.

28. If the appendicitis was in the early stages or was normal the subcutaneous tissue can be closed at the level of Scarpa’s fascia with interrupted or running 2-0 Vicryl suture.

29. The skin is closed with staples, interrupted Nylon sutures, or a subcuticular absorbably suture such as Monocryl

Postoperative Course

Non-ruptured appendicitis – if the procedure was done through a relatively small right lower incision, recovery is usually rapid with patients starting oral feeds and being discharged from the hospital in 1-2 days. If the incision is a larger right lower quadrant incision or a midline incision, recovery is delayed and the hospital course is lengthened by several days.

Ruptured appendicitis – even in the age of modern antibiotics a ruptured appendix is associated with increased morbidity and mortality. If peritonitis is present, it may take the bowel several days to have a return of function and a 2-3 day stay is not unusual, although many patients recover quickly and can be discharged sooner.

Complications

Superficial wound infection – this is a risk with all surgical incisions and is increased if the skin edges are closed in the setting of late appendicitis or rupture.

Intraperitoneal abscess – this is fortunately unusual but can complicate up to 10% of cases of ruptured appendicitis.

Other – as with all surgeries there is always a risk of blood clots, pulmonary embolism, stroke, heart attack, and death.

Copyright 2006 Insidesurgery.com