Protocol Based Selective Imaging Versus Routine Computed Tomography or Ultrasound in Suspected Appendicitis

Study Overview
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Brief Summary
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The goal of this clinical trial is to compare protocol based selective imaging to routine imaging in adult patients with suspected appendicitis. The main question[s] it aims to answer are: Does protocol based selective imaging using clinical scoring affect clinical outcome? Does protocol based selective observation combined with score based selective imaging affect clinical outcome? Participants will be randomized into three groups: Selective imaging based on Adult Appendicitis Score Selective observation based on Appendicitis Severity Score combined with selective imaging based on Adult Appendicitis Score Routine imaging using ultrasound and/or computed tomography Researchers will compare selective imaging groups separately with routine imaging to see if number of negative appendectomies or number of complicated appendicitis is not significantly increased.

Official Title
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Protocol Based Selective Imaging Versus Routine Computed Tomography or Ultrasound in Suspected Appendicitis (PROSECCO)

Conditions
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Appendicitis

Intervention / Treatment
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* Diagnostic Test: Abdominal imaging
* Other: Score based selective abdominal imaging
* Other: Score based selective observation combined with selective abdominal imaging


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Suspicion of appendicitis Exclusion Criteria: Time from symptom onset over 72 hours Age <18 years Pregnancy, ruled out by serum or urine HCG measurement in 18- to 49-year-old women CT-scan or ultrasound already done within the last 3 days (72 hours) Clinical suspicion of other disease or other reason to perform imaging study Recruited earlier to the same trial

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: 1:1:1
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Routine imaging<br>Patients will have first abdominal ultrasound, and if findings are negative or inconclusive for appendicitis abdominal CT scan is made. If ultrasound is not available, CT scan can be the first imaging study. If appendicitis is found in the imaging study patient is scheduled for urgent laparoscopic appendectomy. Other patients are discharged or treated according to possible alternative diagnosis. | Diagnostic Test: Abdominal imaging<br>* Abdominal ultrasound and/or abdominal CT<br>|
| Experimental: Adult Appendicitis Score based selective imaging<br>Adult Appendicitis Score (AAS) is calculated as soon as possible. Patients with AAS 16 or higher are scheduled for urgent laparoscopic appendectomy. Patients with AAS 11- 15 will have abdominal imaging as in the group 1. If appendicitis is found in the imaging study patient is scheduled for urgent laparoscopic appendectomy. Patients with AAS 10 or less are discharged without imaging studies. | Other: Score based selective abdominal imaging<br>* Abdominal imaging is done selectively based on Adult Appendicitis Score<br>|
| Experimental: Appendicitis Severity Score based observation with selective imaging using Adult Appendicitis Score<br>Patients with Adult Appendicitis Score (AAS) 10 or less are discharged without imaging studies. Patients with AAS 11 or more are managed based on Appendicitis Severity Score (ASS). ASS is used to identify patients with low risk of complicated disease. Patients with high ASS (>4) are managed as patients in arm 2. Patients with low ASS (<=4) begin observation protocol where patients can leave hospital and they are re-evaluated with repeated scoring after 12-24 hours from randomization. After re-scoring patients may be discharged if AAS is below 16 and decreasing and ASS is below 5 or if AAS is below 11. If AAS is 16 or higher or increasing, patients are scheduled for urgent laparoscopic appendectomy. After observation period, patients with decreasing AAS between 11-15 and ASS higher than 4 or patients with stable AAS between 11-15 are send for imaging study. | Other: Score based selective observation combined with selective abdominal imaging<br>* Observation based on Appendicitis Severity Score combined Adult Appendicitis Score based selective abdominal imaging<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Negative appendectomy | Number of negative appendectomies (surgical removal of non-inflamed appendix) | Within 30 days from randomization | 
| Complicated appendicitis | Number of patients with complicated appendicitis (AAST grade 3 or higher) | Within 30 days from randomization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| histologically proven appendicitis | Number of patients with histologically proven appendicitis undergoing surgery | Within 30 days from randomization | 
| CT scan | Number of patients having abdominal computed tomography | Within 30 days from randomization | 
| Adverse events | Number patients with of adverse events (surgical complications, surgical site infections or delayed significant diagnosis) | Within one year from randomization | 
| Appendicitis | Number of patients diagnosed with appendicitis | Within 2 years from randomization | 
| Quality of life (EQ-5D-5L index value) | Quality of life determined by weekly EQ-5D-5L index values. | During the first 30 days from randomization | 
| Quality of life (EQ-5D-5L EQ-VAS score) | Quality of life determined by weekly EQ-5D-5L EQ-VAS score. | During the first 30 days from randomization | 
| Costs in Euros | Overall costs of diagnostics and treatment | During the first 30 days from randomization |