Last time we have left the speech halfway. We have seen how scores may help us in the diagnostic approach to patients with suspected acute appendicitis. Today we’re going to explore the different possible ways we can choose depending on the result of the score we used.
As you remember, last time we advocated the use of scores that allow you to stratify patients’ risk of having acute appendicitis. The reason behind this is that we can optimize the management strategy according to the risk group to which the patient belongs.
Let’s see how it works…
We will use just the AIR score for simplicity. However, all risk-stratifying scores can apply to this system.
Kenneth McCormick is a 19-year-old boy who is feverish (37.4°C) and complains about abdominal pain in the right lower quadrant since yesterday. He does not report vomiting. At the clinical examination, Kenny has no rebound tenderness or guarding. Laboratory results show slightly increased white cell count (12500/mm3) with a proportion of polymorphonucleates (PMNs) of 74%, and a C-reactive protein (CRP) of 8 mg/L.
Using the AIR score, he results in having a score of 3, meaning a low risk of acute appendicitis.
What are we going to do with Kenny?
At this point, we are allowed to discharge the patient right away. Nevertheless, we do not advocate it.
First of all, you need to evaluate the urine analysis to exclude possible renal disorders (e.g. renal stones, urinary infection, etc…) which may mimic acute appendicitis (this parameter is considered in the RIPASA score). Second, if the patient is a young woman, you must ask for urine or blood human chorionic gonadotropin levels to exclude pregnancy or related disorders. Third, ask the patient if he had already undergone an appendectomy. We know it seems stupid to ask that, but you cannot imagine how many times we’ve seen this. However, remember the existence of stump appendicitis, which is the inflammation of the remnant appendix due to incomplete removal of the appendix during the index operation (it is rare, but it exists). These aspects must be evaluated in all patients, regardless of their risk group.
Anyhow, Kenny has a negative urine analysis, he is not a young lady, and he has never been subjected to appendectomy. What’s next? Can we discharge him?
We suggest to not discharge him yet but to perform an ultrasound. Ultrasound is cost-effective, safe, and it helps a lot in evaluating patients. We believe it should always follow inspection, palpation, percussion, and auscultation during a clinical examination. However, not all radiologists are skilled in finding the appendix in ultrasound. Our advice is to learn how to properly perform a Point of Care Ultrasound examination focused on the appendix. Maybe we will talk about this in one of the next posts.
If the ultrasound findings are suggestive for acute appendicitis, you can admit the patient and treat him/her accordingly. If the ultrasound is negative or uncertain, you may discharge the patient with/without antibiotics, depending on his/her clinical status. Otherwise, clinical observation for 6-12 hours may be a second option. A follow-up outpatient visit after a couple of days with repeated laboratory exams (and ultrasound) may be a safe and reasonable choice.
What if Kenny has a white cell count of 18000/mm3 with a proportion of PMNs of 85%, and a CRP of 84 mg/L?!
He would have an AIR score of 7, meaning an intermediate-risk of acute appendicitis.
The same as per low-risk patients, US should be the next step in your mental flow-chart. If its result is suggestive of acute appendicitis, the following decision is quite easy. But what if it is unequivocal?!… Or negative?!
In the paper by Scott et al., 44% of patients with an AIR score 5-8 (i.e. intermediate-risk) had acute appendicitis, 33% of whom at an advanced stage. Therefore, if US is unequivocal, contrast-enhanced CT scan seems the best choice to exclude both acute appendicitis and other pathologies mimicking it.
But what about negative US? Is CT scan necessary?
Here we are in the gray zone.
Scott et al. advocate the use of CT scans in patients with intermediate-risk and negative US. However, it may lead to unnecessary patients’ exposure to radiation. Moreover, it appears to be difficult that a patient with complicated acute appendicitis has a completely negative US exam. The same can be said about other complicated intra-abdominal pathologies.
The question to ask is: does CT scan really change my management?
Let’s say CT scan is going to be negative, what are you going to do with the patient? Are you going to discharge him/her?
Maybe, the correct approach to these patients is to admit them for a 12-24 hours observation, starting antibiotics, monitoring their clinical condition, repeating laboratory exams, and US. Then, if there is no improvement (or as soon as their condition deteriorates), contrast-enhanced CT scan should be promptly performed.
Intermediate-risk patients with completely negative US are difficult to manage. There is no correct way. CT scan and the watch-and-wait approach are both reasonable choices. Perhaps the decision on which one to follow should rely on the surgeon’s gut.
Let’s say that this time Kenny complains right iliac fossa pain, vomiting, and fever up to 38.7°C. At the clinical examination, he has strong rebound tenderness in the right lower quadrant. Laboratory results show leukocytosis (WBC 18000/mm3) mainly composed by polymorphonucleates (88%), and increased CRP (148 mg/L).
…And after a quick calculation, Kenny has an AIR score of 12 (highest score ever!!! Go Kenny go!!!).
What’s your choice now? Surgery? CT scan? Discharge? Mortuary?…
It seems legitimate to take all patients falling into the high-risk group to the OR straight away.
However, is it really this simple? Is it the correct thing to do?
Di Saverio et al. differentiate high-risk patients between younger and older than 40 years old. According to their algorithm, those who are younger are addressed to surgery, while the older ones have an additional step: CT scan. The reason is the higher risk of right colonic or appendiceal neoplasms mimicking acute appendicitis.
We do not completely agree on asking a CT scan in all patients older than 40 yo. In fact, the overall risk of unexpected findings, in terms of neoplasms, during “routine” appendectomy is inferior to 2%. In our opinion, this does not justify the use of CT scan. We believe the answer may be ultrasound.
The colon is quite superficial and fixed; thus, it is easy to study with US. Colonic cancer may be suspected/diagnosed with US, mainly if it is large, necrotic, and abscessualized (which are those usually mimicking acute appendicitis). Similarly, appendiceal neoplasms may be recognizable at US too.
As previously stated, the question is: does CT scan change my management?
Let’s say that Kenny is 45 yo and has an unknown abscessualized right colonic cancer with an AIR score of 10 (i.e. high-risk group). According to our reasoning, you ask for (or do) an abdominal US focused on the right iliac fossa.
What are the possible results? And the possible consequences?
- Negative/unequivocal US: ask for CT scan
- US suggestive of colonic or appendiceal tumor: ask for a CT scan
- US suggestive of acute appendicitis
- Conservative management: follow-up colonoscopy ± CT scan
- Operative management: exploratory laparoscopy
- Confirmed acute appendicitis: remove
- Unexpected neoplasm: convert if appropriate, resect
Even if the patient has an unexpected neoplasm and he/she has misdiagnosed metastases and/or peritoneal carcinosis, surgery is indicated because he/she is symptomatic.
In conclusion, in high-risk patients older than 40 yo, we advocate using a CT scan in case of doubt or if US is negative/unequivocal, but not on a routine basis. Moreover, if the decision is to treat the patient conservatively, scheduling a follow-up colonoscopy ± CT scan may be appropriate to exclude misdiagnosed colonic or appendiceal neoplasms.
Now that you know everything on acute appendicitis, go on and operate on anyone!!!
Until next time: be glad, be good, be brave…
- Di Saverio S, et al. Diagnosis and treatment of acute appendicitis: 2020 update of the WSES Jerusalem guidelines. World Journal of Emergency Surgery 2020;15:27.
- Scott AJ, et al. Risk stratification by the Appendicitis Inflammatory Response score to guide decision-making in patients with suspected appendicitis. Br J Surg 2015;102:563-7.
- Richardson NG, et al. Abdominal ultrasonography in the diagnosis of colonic cancer. Br J Surg 1998;85:530-3.
- Pickhardt PJ, et al. Primary neoplasms of the appendix: radiologic spectrum of disease with pathologic correlation. RadioGraphics 2003;23:645-62.
- Steinhagen E, et al. Unexpected findings at appendectomy. In: Sylla P, et al. eds. The SAGES Manual of Colorectal Surgery. 1st Ed. Cham: Springer; 2020:169-81.
How to Cite This Post
Bellio G, Marrano E. All Roads Lead to Appendectomy… or Maybe Not?! Surgical Pizza. Published on July 26, 2020. Accessed on July 31, 2021. Available at [https://surgicalpizza.org/emergency-surgery/all-roads-lead-to-appendectomy-or-maybe-not/].