Learning Outcome

• Recognize the common signs and symptoms of appendicitis 
• Know the key points to assess in an appendicitis patient, both pre and postoperatively
• Recognize when it is necessary to alert the provider to specific patient findings
• Formulate nursing diagnosis related to appendicitis
• Develop and implement a plan of care within the scope of practice for the appendicitis patient

Introduction

Appendicitis is inflammation of the vermiform appendix. This is a small, finger-like, hollow organ located at the tip of the cecum portion of the large intestines, usually in the right lower quadrant of the abdomen. However, it can be located in almost any area of the abdomen, depending on if there were any abnormal developmental issues or if there are any other concomitant conditions such as pregnancy or prior surgeries.  Because the appendix has a small lumen, it is prone to obstruction by fecalith (which is a stone-like substance made from hardened feces) and can subsequently become inflamed and then infected. Appendicitis is one of the most common causes of acute abdominal surgery and typically occurs between ages 5 and 45, but can occur at any age, with men having a slightly higher risk. Appendicitis is most often a disease of acute presentation, usually within 24 hours, but it can also present as a more chronic condition. If there has been a perforation with a contained abscess, then the presenting symptoms can have a slower and less painful onset. The exact function of the appendix has been a debated topic. Today it is accepted that this organ may have an immunoprotective function and acts as a lymphoid organ, especially in the younger person. Other theories contend that the appendix acts as a storage vessel for "good" colonic bacteria. Still, others argue that it is a mear developmental remnant and has no real function.[1][2][3]

Nursing Diagnosis

• Acute pain related to obstructed appendix
• Risk for fluid volume deficit related to nausea and/or vomiting/ decreased appetite/ decreased fluid intake
• Risk for infection related to ruptured appendix/ surgical incision
• Risk for deep venous thrombosis (DVT) related to immobility
• Risk for anxiety related to hospitalization

Causes

The cause of appendicitis likely stems from obstruction of the appendiceal opening or lumen. This results in inflammation, localized ischemia, perforation, and the development of a contained abscess or perforation with resultant peritonitis. This obstruction may be caused by lymphoid hyperplasia, infections (parasitic), fecaliths (stone-like structure made of hardened feces), or benign or malignant tumors. When an obstruction is the cause of appendicitis, it leads to an increase in pressure, resulting in small vessel occlusion and lymphatic stasis. Once obstructed, the appendix fills with mucus and becomes distended, leading to ischemia and necrosis. Bacterial overgrowth then occurs in the obstructed appendix, with aerobic organisms predominating in early appendicitis and mixed aerobes and anaerobes later in the course. Common organisms include Escherichia coli, Peptostreptococcus, Bacteroides, and Pseudomonas. Once significant inflammation and necrosis occur, the appendix is at risk of perforation, leading to a localized abscess and sometimes frank peritonitis.[4]

Risk Factors

Appendicitis is one of the most common causes of acute abdominal surgery in the United States, with more than 200,000 cases occurring annually and typically occurs between ages 5 and 45, but can occur at any age, with men having a slightly higher risk. Family history of appendicitis seems to slightly increase risk, as well as a personal history of cystic fibrosis.

Assessment

Classically, appendicitis presents as an initial generalized or periumbilical abdominal pain that then localizes to the right lower quadrant.  As the appendix becomes more inflamed, and the adjacent parietal peritoneum is irritated, the pain becomes more localized to the right lower quadrant. Pain may or may not be accompanied by any of the following symptoms:

• Decreased appetite
• Nausea/vomiting
• Fever (40% of patients)
• Diarrhea or constipation
• Generalize malaise
• Urinary frequency or urgency

Physical exam findings are often subtle, especially in early appendicitis.

As inflammation progresses, signs of peritoneal inflammation develop. Signs include:

• Right lower quadrant guarding and rebound tenderness
• Right lower quadrant pain elicited by palpation of the left lower quadrant
• Increased abdominal pain with coughing or movement
• Rigid abdomen and involuntary guarding

The time course of symptoms is variable but typically progresses from early appendicitis at 12 to 24 hours to perforation at greater than 48 hours. Seventy-five percent of patients present within 24 hours of the onset of symptoms.

The risk of rupture is variable but is about 2% at 36 hours and increases about 5% every 12 hours after that.

Evaluation

Typically includes:

• Laboratory testing such as CBC. Elevated WBC is typically found, but CBC is normal in approximately one-third of patients with appendicitis.
• Typically a CT abdomen and pelvis is done while the patient is in the emergency room setting, but ultrasound and MRI are also used, particularly in pregnant women, and ultrasound is sometimes used in children to reduce radiation.
• Appendicitis is often a clinical diagnosis by the provider based on a thorough history and physical exam.

Medical Management

The gold-standard treatment for acute appendicitis is to perform an appendectomy. Laparoscopic appendectomy is preferred over the open approach. Most uncomplicated appendectomies are performed laparoscopically. In cases where there is an abscess or advanced infection, the open approach may be needed. The laparoscopic approach affords less pain, quicker recovery, and the ability to explore most of the abdomen through small incisions. Situations, where there is a known abscess from a perforated appendix, may require a percutaneous drainage procedure usually done by an interventional radiologist. This stabilizes the patient and allows the inflammation to subside over time enabling a less difficult laparoscopic appendectomy to be performed at a later date. Practitioners also start patients on broad-spectrum antibiotics. There is some disagreement regarding preoperative antibiotic administration for uncomplicated appendicitis. Some surgeons feel routine antibiotics in these cases are not warranted, while others give them routinely. There have also been several studies promoting the treatment of uncomplicated appendicitis solely with antibiotics and avoiding surgery altogether.[1][5]

Nursing Management

Nursing interventions related to the appendicitis patient include:

• Assessing and relieving pain through medication administration as well as nonpharmacologic interventions.
• IMPORTANT: DO NOT APPLY HEAT TO THE APPENDICITIS PATIENT'S ABDOMEN AS THIS COULD LEAD TO RUPTURE.
• Prevent fluid volume deficit. If tolerated and the patient is not NPO, oral fluid intake should be encouraged, and intake and output recorded.
• Prevent infection. Maintain a clean environment, provide wound care to the postoperative patient, and assess incision frequently for signs of infection. Monitor patient temperature and heart rate for signs of potential infection. Administer antibiotics as prescribed by the provider.
• Reduce patient anxiety by keeping the patient informed of the plan of care and ensure the patient is aware of diagnosis and treatment options. 
• Encourage patients to walk as able/ permitted to maintain circulation. If the patient is immobile, the use of serial compression devices (SCD) and TED hose should be implemented to avoid DVT/clots.
• Monitor for adequate bowel movements. Opioids can be necessary for pain control, but they often lead to constipation. Encourage adequate water intake and use of a stool softener.

When To Seek Help

• Alert the health care provider to symptoms of peritonitis, as this could indicate a ruptured appendix. Symptoms to watch for include severe abdominal pain, typically these patients try not to move and hold their abdomen very still, often even avoiding deep breaths. They demonstrate what is called a board-like abdomen. When touched, the patient will tighten their abdominal muscles as a guarding mechanism, leading the abdomen to appear very firm to touch. If the patient demonstrates these symptoms, it is necessary to alert the provider right away.
• If there is a sudden change to the vital signs such as increased heart rate (tachycardia) or fever, as this could indicate infection or acute inflammation
• If the patient is postoperative, alert healthcare provider to any signs of wound infection such as redness, tenderness, increasing pain, or swelling at the incision site.

Outcome Identification

• Pain decreased/relieved
• Prevented fluid volume deficiency, adequate intake, and output
• Prevented/treated infection
• Maintained surgical incision integrity
• Patient anxiety relieved/received adequate education
• Maintained adequate elimination/prevented constipation

Monitoring

• Monitor vital signs for changes in temperature or heart rate. Fever and increased heart rate can both indicate infection or inflammation.
• Monitor patient pain level and location. Appendicitis typically presents as pain in the right lower quadrant. However, it is not always specific to those areas, particularly in small children, who may have difficulty localizing pain other than a generalized "belly pain." The appendix may also not be situated in a normal location, which can lead to pain felt in a different quadrant. It is important, as a nurse, to obtain as much information as possible about the location and quality of the pain in order to provide the doctor with as much information as possible. Questions such as "where is the pain located?" "How would you describe the pain, is it burning, stabbing, cramping, etc.?" and "How long has the pain lasted, is it constant or does it come and go?" are important to ask the patient and subsequently relay to the provider.
• Monitor for changes in eating and bowel habits. Appendicitis can lead to patient complaints of loss of appetite, nausea, and vomiting, as well as constipation.
• Monitor laboratory values, particularly the white blood cell count, as an increase can signal infection. Please note, however, appendicitis is still possible with normal laboratory values.

Health Teaching and Health Promotion

• If the patient had surgery, they need to continue to monitor the incision site for any signs of infection such as redness, swelling, drainage, or increased pain and report these to their surgeon. 
• They will likely have staples or sutures that will need to be removed in 5-7 days, but regardless they must have a follow-up appointment scheduled with their surgeon or primary provider before they are discharged to follow up for wound check and assessment.
• Normal activity can usually resume within a few days to a week. However, the patient should avoid any strenuous activity and heavy lifting for the first 4-6 weeks, unless otherwise noted by the provider. Frequent small walks should be encouraged.
• If antibiotics were prescribed, ensure adequate patient education to complete all antibiotics and to take with a meal should stomach upset occur.
• If pain medication such as opioids was prescribed, ensure the patient knows not to drive or operate machinery while taking and also to take a stool softener to avoid constipation.
• Encourage patient to unexpected findings to the clinician.

Risk Management

Make sure to document appropriately and timely in the appendicitis patient. Specific documentation for this patient includes:

• Patient description of pain and intensity. 
• Results of laboratory values and if these were called to the provider.
• Surgical site and wound care/dressing changes/any drainage noted if the drain is present and description of drainage (serosanguineous, etc.).
• Signs or symptoms of infection.
• Any patient education provided.
• Plan of care.
• Any time results, patient assessment, or concerns are addressed with the provider. This needs to be documented, including who was paged, who responded, and the time. 

Discharge Planning

• If the patient had surgery, they need to continue to monitor the incision site for any signs of infection such as redness, swelling, drainage, or increased pain and report these to their surgeon. 
• They will likely have staples or sutures, but regardless they must have a follow-up appointment scheduled with their surgeon or primary provider before they are discharged to follow up for wound check and assessment.
• Normal activity can usually resume within a few days to a week. However, the patient should avoid any strenuous activity and heavy lifting for the first 4-6 weeks, unless otherwise noted by the provider. Frequent small walks should be encouraged.
• If antibiotics were prescribed, ensure adequate patient education to complete all antibiotics and to take with a meal should stomach upset occur.
• If pain medication such as opioids was prescribed, ensure the patient knows not to drive or operate machinery while taking and also to take a stool softener to avoid constipation. 

Pearls and Other issues

Special consideration should be given to the treatment of patients with perforated appendicitis with an abscess. Those who present with an abscess and do not exhibit peritonitis may benefit from CT or ultrasound-guided percutaneous drain placement as well as antibiotics. Interval appendectomy is classically performed 6 to 10 weeks after recovery. Historically, 20% to 40 % of patients treated medically for perforated appendicitis with an abscess had recurrent appendicitis in historical literature. More recent studies suggest these rates be much lower.

Complications of appendicitis and appendectomy include surgical site infections, intra-abdominal abscess formation (3% to 4% in open appendectomy and 9% to 24% in laparoscopic appendectomy), prolonged ileus, enterocutaneous fistula, and small bowel obstruction.

Occasionally the incorrect diagnosis of acute appendicitis is made when, in reality, the correct diagnosis is Crohn disease of the cecum or terminal ileum. It is important to know that is this occurs that the appendix should be left in place if there is involvement at its base. The removal of the appendix in this situation has a high leak and fistula rate formation. On the other hand, if the base of the appendix is spared, then the appendix should be removed, even if it appears normal. This eliminates the future confusion of diagnosing acute Crohn disease versus acute appendicitis.

In the past, it was commonplace to routinely remove the appendix at the time of other nonrelated surgeries to avoid developing appendicitis in the future. Today, however, most surgeons do not routinely remove a normal appendix at the time of other scheduled procedures. If a patient does go into surgery for an incorrect diagnosis of acute appendicitis, then it is advised to remove the appendix to avoid any future diagnostic issues.

Review Questions

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Disclosure: Saran Lotfollahzadeh declares no relevant financial relationships with ineligible companies.

Disclosure: Richard Lopez declares no relevant financial relationships with ineligible companies.

Disclosure: Jeffrey Deppen declares no relevant financial relationships with ineligible companies.

Disclosure: Beth Kendall declares no relevant financial relationships with ineligible companies.