Critical Care Medicine-Infections and Immunologic Disease>>>>>Gastrointestinal and Intra-abdominal Infections
Question 5#

A previously healthy 24-year-old man presents to the emergency department with severe right lower quadrant pain, anorexia, and nausea. Vital signs include:

• heart rate 126 beats/min
• blood pressure 86/43 mm Hg
• SpO₂ 99% on room air
• temperature 38.7°C

Physical examination is significant for exquisite right lower quadrant tenderness with rebound and guarding. Laboratory test results reveal a white blood cell count of 19,000 cells/µL with a left shift. CT with contrast shows appendiceal wall thickening, periappendiceal fat stranding, and a focal defect in the enhancing wall of the appendix.

In addition to IV fluids, what are the next best steps in management?

A. Start antibiotics with narrower-spectrum, gram-negative, and anaerobic coverage such as ceftriaxone plus metronidazole, urgent surgery
B. Start antibiotics with broad coverage such as cefepime plus metronidazole, urgent surgery
C. Start antibiotics with narrower-spectrum gram-negative and anaerobic coverage such as ceftriaxone plus metronidazole, surgery within 24 hours
D. Start antibiotics with broad coverage such as cefepime plus metronidazole, surgery within 24 hours
E. Start antibiotics with broad coverage such as cefepime plus metronidazole, no surgery unless the patient does not improve with antibiotics and fluids

Correct Answer is A

Comment:

Correct Answer: A

This patient’s clinical picture is consistent with perforated appendicitis. Even in the absence of imaging findings, the positive peritoneal signs, hypotension, significantly elevated temperature, and high white blood cell count point to a serious intra-abdominal infection that requires exploration. In the setting of imaging consistent with acute appendicitis, five sensitive and specific CT findings for perforated appendicitis include abscess, phlegmon, extraluminal air, extraluminal appendicolith, and focal defect in the enhancing appendiceal wall. A focal defect in the appendiceal wall is the most sensitive finding. However, up to half of patients with perforated appendicitis will have imaging consistent with simple appendicitis, so imaging by itself cannot rule out perforation. 

An intravenous fluid bolus is indicated to treat the patient’s hypotension. Because this patient is otherwise healthy and presenting from home, he is not considered to be at an increased risk for resistant or hospital-associated organisms. Coverage of narrower gram-negative and obligate anaerobic organisms is adequate despite the severity of the infection. Recommended single agents include ertapenem and moxifloxacin. Combination regimens could include cefotaxime or ceftriaxone plus metronidazole or ciprofloxacin plus metronidazole. No more than 4 days of antibiotic therapy is recommended for patients with perforated appendicitis who undergo surgery and have adequate source control. Although antibiotics alone have been shown to be successful in simple inflamed appendicitis, 25% to 30% of patients will require readmission or surgery within 1 year. Appendectomy is still recommended for most patients presenting with appendicitis. Patients such as this one with sepsis or peritonitis due to acute appendicitis require urgent surgery. Timing of appendectomy in mild to moderate cases of appendicitis has been more controversial, but delays of 12 to 24 hours have not been associated with increased rates of complications such as perforation.

References:

1. Bhangu A, Søreide K, Di Saverio S, et al. Acute appendicitis: modern understanding of pathogenesis, diagnosis, and management. Lancet. 2015;386(10000):1278-1287.
2. Horrow MM, White DS, Horrow JC. Differentiation of perforated from nonperforated appendicitis at CT. Radiology. 2003;227(1):46-51
3. Leeuwenburgh MM, Wiezer MJ, Wiarda BM, et al. Accuracy of MRI compared with ultrasound imaging and selective use of CT to discriminate simple from perforated appendicitis. Br J Surg. 2014;101(1):e147-e155.
4. Mazuski JE, Tessier JM, May AK, et al. The Surgical Infection Society revised guidelines on the management of intra-abdominal infection. Surg Infect (Larchmt). 2017;18(1):1-76.
5. United Kingdom National Research Collaborative, Bhangu A. Safety of short, in-hospital delays in surgery for acute appendicitis: a multicenter cohort study, systematic review, and meta-analysis. An Surg. 2014;259(5):894-903.