Diagnostic Utility of Repeat CT Scans of the Abdomen and Pelvis in Emergency Department Patients Presenting with Non-traumatic Abdominal Pain. Kristin James Joe Kidd Lance Ridpath Objectives Conclusion Results The study results demonstrated that half of the repeat CT scans ordered were positive and half were negative. According to the hypothesis it was expected that more CT scans would be negative than positive. The data failed to demonstrate this. The data also failed to demonstrate a correlation between clinical factors and likelihood of a positive CT scan. The data did not provide statistically important correlations that physicians could use in their decision making when it comes to ordering repeat CT scans of the abdomen and pelvis. This may have been due to several study limitations including study population sizenand the fact that that the hospitals sampled where teaching hospitals where residents place orders and may order more CT scans than a experienced clinican. Overall the study did demonstrate that we order CT scans in scenarios that give us positive results. This is better than what was initially hypothesized, but we can still improve. Hypothesis: Repeat CT of the abdomen/pelvis in non-traumatic patients who present to the ED multiple times in a year for vague abdominal pain will provide little additional diagnostic information from previous CTs of the abdomen and pelvis. A total of 293 ct scans of the abdomen and pelvis were evaluated. 149 scans were negative and 144 were positive. 219 of those scans resulted in a home disposition. None of the individual measures showed a significantly greater probability of having a positive CT Scan. However, this may have been the result of having a small incidence size. For example, out of 293 subjects, only four had elevated LFT’s. Within that group, three had a positive CT Scan (75%). If the sample size were 50% larger, you might see a significant result. The same is probably true for Heart rate over 100. Text Background The use of diagnostic CT scan has grown exponentially over the last decade. It is estimated that 62 million CT scans are obtained yearly as compared to 3 million in 1980 (1). Large portions of those are ordered out of the Emergency Room. The implications of this rise in CT use cause some debate. CT scans are not without risk. CT scans expose patients to radiation, some use IVP dye that can damage kidneys and cause allergic reactions that can be life threatening and lastly they can be a cost burden to the patients and healthcare providers. A recent study published in the Archives of Internal Medicine 2009 attempted to project the correlation between radiation exposure from CT scans and caner risks. The study used risk models based on the National Research Council’s “Biological effects of Ionizing Radiation” report. The authors of the study concluded that 29,000 future cancers could be related to CT scans preformed in the year 2007 alone where a total number of CT scans approximated near 57 million in the U.S for that year. They cited that the majority would come from CT scans of the abdomen and pelvis (2,3). According to literature reviews done in Up to Date, 3 percent of patients will suffer acute renal failure after the administration of IV dye and the number rises to 25 percent of patients with an already elevated creatinine (above 2.0mg/dl) (6,7). The sequelae of acute renal failure is that it raises the risk of in hospital mortality from 1.4 to 22 percent (6,7). Our study was designed to look at repeat CT scans of the abdomen and pelvis done within a 1 year time frame to determine if they were of diagnostic utility. Our study also examined different variable including labs values and vitals signs to determine if there was a correlation between them and the lkely hood of having a postive CT Radiation doses of common procedures Photos. graphics , xrays,???? Class size before expansion Methods References Stud Data was collected in regards totivevs negative CT scans, disposition and clinical findings. Clinical findings studied were vitals, labs, and physical exam. The dispositions studied were discharge to home vsadmissionral or antibiotics. The data was analyzed to determine what percent of repeat CT scans were negative. A secondary analysis was conducted to determine if there was a correlation between certain clinical findings and the likelihood of a positive CT scan. . David J Brenner, Ph.D., D.Sc., and Eric J. Hall, D.l Phil., D.Sc., voume 357:2277-2284 November 29, (2007). Computed Tomography-An Increasing source of Radiation Exposure 2. “Radiation Dose Associated with Common Computed Tomography Examinations and the Associated Lifetime Attributable Risk of Cancer,” abstract, Archives of Internal Medicine, Dec. 14/28, 2009 (archinte.ama- assn.org/cgi/content/abstract/169/22/2078) 3. “Projected Cancer Risks from Computed Tomographic Scans Performed in the United States in 2007,” abstract, Archives of Internal Medicine, Dec. 14/28, 2009 (archinte.ama- assn.org/cgi/content/abstract/169/22/2071) 4. “ACR Statement on Recent Studies Regarding CT Scans and Increased Cancer Risks,” American College of Radiology, Dec 15, 2009. (www.acr.org/HomePageCategories/News/ACRNewsCenter/StatementonRecentStudiesRegardingCTScans.aspx) 5. http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty xray 6. McCullough PA, Wolyn R, Rocher LL, et al. Acute renal failure after coronary intervention: incidence, risk factors, and relationship to mortality. Am J Med 1997; 103:368. 7. Nikolsky E, Mehran R, Lasic Z, et al. Low hematocrit predicts contrast-induced nephropathy after percutaneous coronary interventions. Kidney Int 2005; 67:706 8. Heyman SN, Rosen S. Semin Nephrol. 2003 Sep;23(5):477-85. Review. PMID: 13680537 [PubMed - indexed for MEDLINE] 9. http://hps.org/hpspublications/articles/dosesfrommedicalradiation.html Study Design: Retrospective study, reviewing charts of Emergency Room visits of two hospitals for a years 2009 and 2010. Key words were used to search the data base of charts among two hospitals staffed by several shared Emergency Medicine physicians to obtain a list of patients who had at least two CT scans of the abdomen and pelvis in a 365 day period. Data was collected in regards to positive vs negative CT scans, disposition and clinical findings. Clinical findings studied were vitals, labs, and physical exam. The dispositions studied were discharge to home vs admission, referral antibiotics. The data was analyzed to determine what percent of repeat CT scans were negative. A secondary analysis was conducted to determine if there was a correlation between certain clinical findings and the likelihood of a positive CT scan.