Background: In January 1998, Rao et al published a study that demonstrated the utility of CT scanning in establishing the diagnosis of appendicitis. In January 2000, a Department of Surgery Grand Rounds reviewed Rao's report. We sought to determine the impact of these two methods of dissemination of information on clinical practice at our institution as well as our negative appendectomy rate.
Methods: To determine the baseline rate of CT scanning for suspected appendicitis, we used data from calendar year (CY) 1997. To determine the impact of the journal article, we used data from CY 1999. To determine the impact of grand rounds, we used data from January to June 2000. All patients discharged during these periods with the diagnosis of appendicitis, ICD-9 billing code of appendicitis or CPT code for appendectomy were identified. Charts and electronic medical records were reviewed for demographic data, findings on history and physical examination, laboratory data, results of preoperative imaging and pathology. Data was analyzed using descriptive statistics and chi square analysis.
Results: There were a total of 262 patients who underwent appendectomy during the time periods of this study. Of these, records of 230 patients (88%) were available for review. Average age was 38 years. Percent male and admission white blood cell count did not differ among the groups. Rate of CT scanning, negative appendectomy rate and rate of perforated or gangrenous appendicitis are shown in the table.
Conclusions: One year after publication of a study in a widely read journal, the use of CT scans in appendicitis had increased markedly, but was still below 50% and scanning at this rate did not impact either the rate of perforated/gangrenous appendicitis nor the negative appendectomy rate. After discussion of the topic in Grand Rounds, the rate of CT scanning increased further which significantly impacted the rate of perforated/gangrenous appendicitis.
CY 1997 CY 1999 Jan-June 2000
n 96 84 50
% with CT 6.7 43.3 70.2
% neg appy 6.3* 6.0* 2.0*
% perf/gang 33.7** 30.9 12.5**
*p<0.001, **p=0.012