Computed tomography in acute abdominal pain: an overused investigation?

Chief complaints and computed tomography results in the emergency department: a three-year retrospective cohort study

BACKGROUND

Computed tomography (CT) is frequently performed in the patients who admitted to the emergency department (ED), discharged but returned to ED within 72 h. It is unknown whether the main complaints of patients assist physicians to use CT effectively. This study aimed to find the association between chief complaints and the CT results.

METHODS

This three-year retrospective cohort study was conducted in the ED of a tertiary medical center. Adult patients who returned to the ED after the index visit were included from 2019 to 2021. Demographics, pre-existing diseases, chief complaints, and CT region were recorded by independent ED physicians. A logistic regression model with an odds ratio (OR) and 95% confidence interval (CI) was used to determine the relationship between chief complaints and positive CT results.

RESULTS

In total, 7,699 patients revisited ED after the index visit; 1,202 (15.6%) received CT. The top chief complaints in patients who received CT were abdominal pain, dizziness, and muscle weakness. Patients with abdominal pain or gastrointestinal symptoms had a significantly higher rate of positive abdominopelvic CT than those without it (OR 2.83, 95% CI 1.98-4.05, p < 0.001), while the central nervous system and cardiopulmonary chief complaints were not associated (or negatively associated) with new positive CT findings.

CONCLUSION

Chief complaints of patients on revisit to the ED are associated with different yields of new findings when CT scans of the chest, abdomen and head are performed. Physicians should consider these differential likelihoods of new positive findings based on these data.

Gallstones Detection on Dual-Energy Computerized Tomography-Is It Ready for Real-World Use? A Retrospective Observational Study

AIMS

The aims of the study are to evaluate the performance of dual-energy computed tomography (DECT) imaging in the detection of noncalcified gallstones (GSs) and to assess its performance relative to transabdominal ultrasound (US) in identifying cholelithiasis.

METHOD

This study is a retrospective review of radiology records and images to find all patients who had both US and DECT scans within a 6-month period and were found to have GSs. Patients who did not have GSs on US served as the control group. The CT scans were reviewed by 4 radiologists who did not have access to the US results when assessing the presence or absence of GSs on the DECT scans. In case of any discrepancies among the radiologists, the majority opinion was considered. If there was a split opinion, a fifth reviewer was consulted. The data were analyzed to calculate sensitivity, specificity, positive and negative predictive values, as well as overall accuracy and to evaluate interreader variability. The absolute Hounsfield unit (HU) differences of the GSs and bile were compared between polychromatic (PC), virtual noncontrast (VNC), and virtual monochromatic (VMC) images.

RESULTS

Considering at least 3-reader agreement, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were found to be 92%, 96%, 96%, 92%, and 94%, respectively. Individual reader sensitivity varied between 87% and 92%. There was good interobserver agreement with a Fleiss' kappa of 0.76. Quantification of the whole data set showed that no significant difference was observed in the HU values for the stones between the PC images and the VNC images. A significant increase was observed on the 50-keV VMC images compared with the PC and VNC images. In the study group, 17% stones were visualized only on the VNC or/and 50-keV VMC images, and not on the PC images. On quantitative analysis of these cases, there was a significant increase of HU in the VNC images as compared with PC images and a significant decrease of HU in the 50-keV VMC images as compared with PC images.

CONCLUSIONS

Low-keV images increase stone-bile contrast. Evaluation of cholelithiasis using VNC and 50-keV VMC images demonstrated a 14% increase in sensitivity relative to conventional CT.

e Silva L, Bellolio F, Upadhye S, Broder JS. Repeat computed tomography in recurrent abdominal pain: An evidence synthesis for guidelines for reasonable and appropriate care in the emergency department

OBJECTIVE

Computed tomography (CT) imaging is frequently obtained for recurrent abdominal pain after a prior emergency department (ED) evaluation. We evaluate the utility of repeat CT imaging following an indeterminate index CT in low-risk abdominal pain adult ED patients.

METHODS

An electronic search was designed for the patient-intervention-control-outcome-timing (PICOT) question: (P) adult patients with low-risk, recurrent, and previously undifferentiated atraumatic abdominal pain presenting to the ED after an index-negative CT within 12 months; (I) repeat CT versus (C) no repeat CT; for (O) abdominal surgery or other invasive procedure, mortality, identification of potentially life-threatening diagnosis, and hospital and intensive care unit admission rates; and return ED visit (T), all within 30 days. Four reviewers independently selected evidence for inclusion and then synthesized the results around the most prevalent themes of repeat CT timing, diagnostic yield, ionizing radiation exposure, and predictors of repetitive imaging.

RESULTS

Although 637 articles and abstracts were identified, no direct evidence was found. Thirteen documents were synthesized as indirect evidence. None of the indirect evidence defined a low-risk subset of abdominal pain nor did investigators describe whether reimaging occurred for complaints similar to the initial ED evaluation. Included studies did not describe the index CT findings and some reported explanatory findings noted on the original CT for which repeat CTs might have been indicated. The time frame for a repeat CT ranged from hours to 1 year. The frequency of repeat CTs (2%-47%) varied across studies as did the yield of imaging to alter downstream clinical decision making (range = 5%-67%).

CONCLUSION

Due to the absence of direct evidence our scoping review is unable to provide high-quality evidence-based recommendations upon which to confidently base an imaging practice guideline. There is no evidence to support or refute performing a CT for low-risk recurrent abdominal pain.

Visualizing the Invisible: Invisible Waste in Diagnostic Imaging

There is extensive waste in diagnostic imaging, at the same time as there are long waiting lists. While the problem of waste in diagnostics has been known for a long time, the problem persists. Accordingly, the objective of this study is to investigate various types of waste in imaging and why they are so pervasive and persistent in today's health services. After a short overview of different conceptions and types of waste in diagnostic imaging (in radiology), we identify two reasons why these types of waste are so difficult to address: (1) they are invisible in the healthcare system and (2) wasteful imaging is driven by strong external forces and internal drivers. Lastly, we present specific measures to address wasteful imaging. Visualizing and identifying the waste in diagnostic imaging and its ingrained drivers is one important way to improve the quality and efficiency of healthcare services.

Influence of CT utilisation on patient flow in the emergency department: a retrospective 1-year cohort study

OBJECTIVE

CT, an important diagnostic tool in the emergency department (ED), might increase the ED length of stay (LOS). Considering the issue of ED overcrowding, it is important to evaluate whether CT use delays or facilitates patient disposition in the ED.

DESIGN

A retrospective 1-year cohort study.

SETTING

5 EDs within the same healthcare system dispersed nationwide in Taiwan.

PARTICIPANTS

All adult non-trauma patients who visited the 5 EDs from 1 July 2011 to 30 June 2012.

INTERVENTIONS

Patients were grouped by whether or not they underwent a CT scan (CT and non-CT groups, respectively).

PRIMARY AND SECONDARY OUTCOME MEASURES

The ED LOS and hospital LOS between patients who had and had not undergone CT scans were compared by stratifying different dispositions and diagnoses.

RESULTS

CT use prolonged patient ED LOS among those who were directly discharged from the ED. Among patients admitted to the observation unit and then discharged, patients diagnosed with nervous system disease had shorter ED LOS if they underwent a CT scan. CT use facilitated patient admission to the general ward. CT use also accelerated patients' admission to the intensive care unit (ICU) for patients with nervous system disease, neoplasm and digestive disease. Finally, patients admitted to the general wards had shorter hospital LOS if they underwent CT scans in the ED.

CONCLUSIONS

CT use did not seem to have delayed patient disposition in ED. While CT use facilitated patient disposition if they were finally hospitalised, it mildly prolonged ED LOS in cases of patients discharged from the ED.