Pre-operative CT predictors associated with 30-day adverse events in patients with appendiceal inflammatory masses who underwent immediate appendectomies

Right hydronephrosis as a sign of complicated appendicitis

OBJECTIVE

Acute appendicitis is known for one of the most common cause of acute abdomen. However, it is still challenging to clearly distinguish complicated from uncomplicated appendicitis preoperatively. We investigated the association between right hydronephrosis and complicated appendicitis compared with other computed tomography (CT) findings of acute appendicitis.

MATERIALS AND METHODS

1275 patients who pathologically diagnosed with acute appendicitis were included. They were classified into the complicated appendicitis and uncomplicated appendicitis groups based on their histopathological results. We reviewed their CT findings, including right hydronephrosis, appendiceal wall defect, periappendiceal abscess, extraluminal or intraluminal free air, appendicolith, appendiceal dilatation, appendiceal wall thickening, periappendiceal infiltration, periappendiceal fluid collection, and ascites. Comparison between the two groups was performed and the diagnostic performance of each CT finding was evaluated. The location of appendix and periureteral extension of periappendiceal infiltration were evaluated in patients with right hydronephrosis.

RESULTS

Out of 1275 patients, 29 (2.3 %) patients showed right hydronephrosis. Right hydronephrosis was significantly related to complicated appendicitis with the odds ratio of 4.90 (95 % confidence interval, 1.62-14.83; P = 0.005). Right hydronephrosis yielded specificity of 99.3 %. All patients with right hydronephrosis accompanied with periappendiceal infiltration and 28 (96.6 %) patients showed periureteral extension. Subcecal and pelvic areas are the most common locations, with 11 (37.9 %) patients each.

CONCLUSION

The presence of right hydronephrosis was specific finding for complicated appendicitis and it could be considered as one of indirect sign of complicated appendicitis.

Are Preoperative CT Findings Useful for Predicting Postoperative Intraabdominal Abscess in the Patients with Acute Appendicitis?

Background and objective: In patients with acute appendicitis (AA), preoperative computed tomography (CT) findings suggesting development of intraabdominal abscess (IAA) had not been widely used. The aim of this study was to investigate the preoperative clinical and radiological factors that predict the development of a postoperative IAA in patients with AA who were treated by laparoscopic appendectomy (LA). Methods: Two hundred and sixteen patients with pathologically proven AA underwent LA between January 2013 and March 2018 in our department. Medical records and preoperative CT images of these 216 patients were retrospectively reviewed and the predictive factors of postoperative IAA were investigated. In addition, patients were divided into complicated appendicitis (CA) and simple appendicitis (SA) and perioperative factors of two groups were compared. Results: One hundred and forty-seven patients were diagnosed with CA, while the other 69 patients were diagnosed with SA. Sixteen patients developed postoperative IAA in the CA group, while no patients in the SA group did. The univariate analysis revealed that time from onset to surgery more than 3 days (p = 0.011), the preoperative CT finding of periappendiceal fluid (p = 0.003), abscess (p < 0.001), and free air (p < 0.001), operation time more than 120 min (p = 0.023) and placement of a drainage tube (p < 0.001) were significantly associated with the development of IAA. Multivariate analysis revealed that the preoperative CT finding of free air was independently associated with the development of IAA (p = 0.007, odds ratio = 5.427, 95% CI: 1.586⁻18.57). Conclusions: IAA developed predominantly in patients with CA. Preoperative CT findings of free air was found to be an independent predictor for the development of IAA. Surgeons should be meticulous in managing the postoperative course of patients with this finding.

Should ambulatory appendectomy become the standard treatment for acute appendicitis?

Background

Appendectomy is increasingly performed as a 'short stay' or 'ambulatory' procedure, yet there is no consensus for selection of patients with acute appendicitis for ambulatory surgery (AS). We aimed to compare characteristics and outcomes of complicated and uncomplicated appendectomies performed in ambulatory vs. conventional settings, and to determine factors associated with unexpected re-consultations and re-hospitalizations.

Methods

The authors reviewed a consecutive series of 185 laparoscopic appendectomies. Whenever possible, patients were offered AS, defined as 'discharge on the same working day.' Multivariable regressions were performed to determine associations of unexpected re-consultations and re-hospitalizations with surgery type (ambulatory or conventional) and patient characteristics (age, gender, obesity, symptoms, appendicolith, perforations, appendix diameter, serologic results, American Society of Anesthesiologists score, and Saint-Antoine score).

Results

From the initial cohort, 117 patients (63.2%) were eligible for AS, of which 8 had peri- or post-operative contraindications. Therefore, 109 patients (58.9%) were operated by AS, with median length of stay 8.5 h (range, 3.3-20.5). Ambulatory cases had a lower incidence of complications (11.9%) than conventional cases (25.0%) (p = 0.029). Uni- and multi-variable regressions revealed that unexpected re-consultations were not significantly associated with any of the pre- or peri-operative variables but that unexpected re-hospitalizations were 4 times more likely for patients with appendicolith (OR, 4.32; p = 0.04).

Conclusions

Ambulatory surgery could be considered as a standard procedure for both complicated and uncomplicated acute appendicitis. Appendicolith was found to be an independent risk factor for unexpected re-hospitalization and should therefore trigger closer monitoring.

The Reliability of a Standardized Reporting System for the Diagnosis of Appendicitis

PURPOSE

Computed tomography (CT) is a fast and ubiquitous tool to evaluate intra-abdominal organs and diagnose appendicitis. However, traditional CT reporting does not necessarily capture the degree of uncertainty and indeterminate findings are still common. The purpose of this study was to evaluate the reproducibility of a standardized CT reporting system for appendicitis across a large population and the system's impact on radiologists' certainty in diagnosing appendicitis.

METHODS

Using a previously described standardized reporting system, eight radiologists retrospectively evaluated CT scans, blinded to all clinical information, in a stratified random sample of 237 patients from a larger cohort of patients imaged for possible appendicitis (2010-2014). Receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were used to evaluate the diagnostic performance of readers for identifying appendicitis. Two-thirds of these scans were randomly selected to be independently read by a second reader, using the original CT reports to balance the number of positive, negative and indeterminate exams across all readers. Inter-reader agreement was evaluated.

RESULTS

There were 113 patients with appendicitis (mean age 38, 67% male). Using the standardized report, radiologists were highly accurate at identifying appendicitis (AUC=0.968, 95%CI confidence interval: 0.95, 0.99. Inter-reader agreement was >80% for most objective findings, and certainty in diagnosing appendicitis was high and reproducible (AUC=0.955 and AUC=0.936 for the first and second readers, respectively).

CONCLUSIONS

Using a standardized reporting system resulted in high reproducibility of objective CT findings for appendicitis and achieved high diagnostic accuracy in an at-risk population. Predictive tools based on this reporting system may further improve communication about certainty in diagnosis and guide patient management, especially when CT findings are indeterminate.

Impact of high-grade obstruction on outcomes in patients with appendiceal inflammatory masses managed by nonoperative treatment

Purpose

To retrospectively assess the impact of high-grade obstructions identified on initial CT on outcomes of patients with appendiceal inflammatory masses managed by nonoperative treatment.

Methods

Institutional Review Boards approved this retrospective study and informed consent was waived. Included were 52 consecutive patients diagnosed with appendiceal inflammatory masses by CT scan and managed by nonoperative treatment. The main outcome measure was treatment failure and secondary outcomes were complications and initial and total hospital stay. Patient demographics, inflammatory markers, and CT findings for presence of an appendiceal inflammatory mass and high-grade obstruction were assessed. Patients with and without high-grade obstruction were compared for patient characteristics and outcomes using Fisher exact test and Student t-test.

Results

Among 52 patients, 14 (27%) had high-grade obstruction on CT examination at presentation. No significant differences were observed in patient characteristics (P > 0.05), treatment failure (P = 0.33), complications (P = 0.29), or initial (P = 0.73) or total (P = 0.72) hospitalization between patients with and without high-grade obstruction.

Conclusion

For patients who were managed by nonoperative treatment for appendiceal inflammatory masses, the presence of high-grade obstruction identified on initial CT scan did not significantly affect outcomes of treatment failure, complications, and initial and total hospitalization.