Appendicitis

00:01 Welcome. In this talk, we're going to cover appendicitis. Literally, inflammation of the appendix.

00:09 Epidemiology first. The lifetime risk is about 10% which is a fairly substantial portion of the population who will eventually have appendicitis.

00:20 The peak incidence is in the young adult, late teen's period of time.

00:28 Males develop this more frequently than females for reasons that I don't entirely understand myself.

00:34 It is the most common acute surgical problem in the pediatric population.

00:39 The pathophysiology. So, in children and young adults, there is associated with a variety of GI and even extraintestinal inflammation.

00:49 Follicular lymphoid hyperplasia that occurs throughout the GI tract but can also prominently involve the appendix.

00:58 As those lymphoid follicles expand, they can compromise luminal outflow from the appendix and that can lead to the appendicitis. They may also locally have increased cellular turnover and that turnover may lead to the production of uric acid that can cause an innate immune response that's been somewhat likened to gout. In older adults, the more common ideology is not this follicular lymphoid hyperplasia, but rather, faecalis which is what it sounds like.

01:35 It's little rocks of hard stool that get impacted in the proximal portion of the appendix.

01:42 You can have calculi that are occurring because of mucus, brine.

01:48 You can have fibrosis that occurs because of local inflammation and if that occurs at the tip of the appendix, no problem, but if it occurs more proximally, potential problem is that limits movement of material out of the appendix.

02:00 And rarely, tumors or parasites can be a cause of appendicitis. So, exactly what is happening here? Highlighted in green is our appendix sitting at the base of the cecum.

02:12 And normally, this is a tubular structure that drains epithelial sloughing and mucus into the cecum.

02:22 So, it is another part of the GI tract. Focal inflammation can cause distal dilation, not too surprising.

02:33 If you have focal inflammation more proximally, in the early time, first 24 hours, you'll have referred pain that is associated with an inflammation and the way that the viscera have their neural connections, it will - the pain will be referred to the umbilicus. It's the stimulation of the TA to T10 afferent nerves.

02:53 In a significant number of cases, about a fifth overall, the symptoms will spontaneously resolve in less than 24 hours.

03:01 The inflammation is reduced, the edema is reduced. There's normal movement of material out of the appendix.

03:08 You're good to go. However, if you are not able to resolve that proximal occlusion, then, there will be bacterial overgrowth more distally. There's going to be further dilation of the distal appendix because we're sloughing epithelium, we're sloughing mucus, and the bacteria are happily growing.

03:29 And in those cases, symptoms will last longer than a couple days. And it gets localized now to right over the appendix.

03:38 So, it starts at the umbilicus and then, moves to the right lower quadrant at McBurney's point.

03:44 Finally, if we don't get resolution of this proximal inflammation and obstruction, we will get so much pressure within the lumen of the appendix that we compromise our arterial blood supply into the appendix and we'll get ischemic necrosis in up to 50 - in up to 20% of cases, a fifth, we can actually get frank perforation which will lead to peritonitis. How do these patients present? So, again, the initial pain is periumbilical that later migrates to the right lower quadrant and the point there is called McBurney's point.

04:22 It's about 2/3rds of the way from the umbilicus to the anterior superior iliac spine, abbreviated there as ASIS.

04:29 So, you will have anorexia, nausea, vomiting, fever, indigestion, diarrhea, generalized malaise, a whole variety of symptoms that are non-specific. Just because you have these doesn't mean you have appendicitis but those are the common findings and you'll want to listen to the appropriate history. Also shown on this image is Rovsing's sign.

04:50 And Rovsing was a surgeon and he discovered that if he pressed on the contralateral side, he could elicit pain over the appendix and that's kind of a - because of edema and traction, you're able to get an indirect pain sign. Neither McBurney's point sign, periumbilical sign, or Rovsing's sign are absolutely pathopneumonic for appendicitis but if you find them, you can feel more confident in your diagnosis.

05:24 So, how do we formally make the diagnosis and really prove the point? Well, it's a combination of things. And in fact, as we'll see, we want the surgeons to air on the side of not missing appendicitis. So, they may take out normal appendices with a certain degree of regularity and that's okay. That is not malpractice.

05:43 So, with appendicitis, we typically would expect a low-grade fever.

05:46 If there's a high-grade fever, we may actually suspect that there's been perforation.

05:51 There will be rebound tenderness and abdominal guarding particularly over the area of the appendix and then, we will see on laboratory findings increased white cells, increased C-reactive protein, increased erythrocyte sedimentation rate, inflammatory markers.

06:06 We will want to exclude other causes. Clearly, if there's a urinary tract infection or a urinary stone or pregnancy, going in and removing the appendix is not going to be all that helpful.

06:16 So, you do want to be relatively certain that you're dealing with an inflammation of the appendix.

06:21 An ultrasound is shown here of where we're seeing prominent edema and dilation of the appendicle wall that's between the two X's is a way to say, "Oh, yes, this is definitely appendicitis." And then, the management. So, you would want to for your patient, give them pain control, nausea control.

06:44 If you are worried about the possibility of infection or impending perforation, you would give intravenous antibiotics.

06:52 And then, you call your friendly neighborhood surgeon who would take them for an appendectomy.

06:57 This makes the point that a negative appendectomy, meaning, surgery without appendicitis actually being present is present, should be present in about 10 to 15% of appendices that are taken out.

07:10 That's an acceptable fault negative rate that we want the surgeons to air on the side of taking out an okay appendix and not missing the appendix that's going to rupture. And with that, we've covered appendicitis.