Suspected Renal Colic in the Emergency Department Who Needs Urologic Intervention? Yan JW, McLeod SL, Edmonds ML, Sedran RJ, Theakston KD CAEP June 4, 2012
Disclosure No conflicts of interest to declare
Background Renal colic is a common emergency department (ED) presentation Relatively benign disease that usually only requires symptom management Most patients pass their stones spontaneously few require urologic intervention ti
Background Analyzed natural history of stone passage in patients with ureterolithiasis Small sample size of 75 patients followed prospectively for spontaneous stone passage Stone Size (mm) Required Intervention % <2 2/41 5 2 4 3/18 17 4 6 8/16 50 Miller et al., (J Urol 1999)
Background Relationship of spontaneous passage to size and location as revealed by CT Retrospective enrollment of 172 patients Location Spontaneous Passage Proximal 48% Mid 60% Distal 75% UVJ 79% Coll et al., (Am J Roentgenol 2002)
Background Coll et al., (Am J Roentgenol 2002) Stone Size (mm) Spontaneous Passage (%) 1 87 2 4 76 5 7 60 7 9 48 >9 25
Study Objectives To confirm the previously reported risk factors in a Canadian tertiary care centre To identify any other risk factors associated with ihthe need for urologic intervention i within ihi 90 days for patients who present to the ED with ihsuspected renal colic
Methodology Prospective cohort study (Oct 2010 Oct 2011) Adult patients with suspected renal colic Academic tertiary care center consisting of 2 EDs with a combined annual census of 120,000 in London, ON
Methodology Ti Triage nurses instructed to flag patients with ihany clinical suspicion of renal colic Eligibility was confirmed by attending physician who also obtained informed written consent for study enrollment
Methodology Trained research assistants extracted data from charts using a standardized data collection tool 90 day electronic chart review for repeat ED visits, outpatient urology visits or urologic intervention
Patient Enrollment Patients Screened for Eligibility N = 514 Patients Enrolled n = 397 Excluded for Definite Alternate Diagnoses n = 38 Patients Included in the Analysis n = 359
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results: Demographics Outcome n = 359 Male 224 (62.4%) Mean (SD) age (years) 47.1 (14.4) Previous history of renal colic 161 (44.8%) CTAS 2 156 (43.5%) CTAS 3 168 (46.8%) CTAS 4 33 (9.2%) CTAS 5 2 (0.5%) Mean (SD) pain score at triage 7 (2.8) Hematuria on urinalysis 291 (81.1%)
Results Of 359 patients, 161 (44.8%) patients had a stone confirmed by some form of diagnostic imaging 57 (15.9%) patients ultimately required urologic intervention within 90 days of their initial visit
Data Analysis Backwards, stepwise multivariablelogistic logistic regression was used to determine predictor variables independently associated with need for intervention
Variables Considered in the Model Demographics Male Age 60 CTAS Previous Renal Colic Pain Score at Triage Duration of Pain Bloodwork Abnormal WBCs Abnormal Hgb Abnormal Creatinine Imaging Any stone Seen Proximal Stone 5 mm Stone Hydronephrosis Absent Ureteric Jet Perinephric Fluid Urinalysis Nitrites Leukocytes Hematuria
Data Analysis Predictor n Odds 95% CI Intervention Ratio n (%) Stone size 5mm 94 3.8 1.9, 7.5 33 (35.1%) Leukocytes on urinalysis 54 3.0 1.5, 6.3 17 (31.5%) Proximal stone 41 2.9 1.3, 6.6 19 (46.3%) Previous history of 162 1.9 1.9, 3.6 31 (19.1%) renal colic
Conclusions Largest agestpospect prospective eed based renal colic c study Four risk factors independently associated with urologic intervention within 90 days: Stone size 5mm Leukocytes on urinalysis Proximal stone Previous history of renal colic
Conclusions Patients with these risk factors have a higher likelihood of requiring urologic intervention and should be considered for early urologic follow up
Limitations Single centre Selection bias clinical suspicion of renal colic at triage Enrollment tfti fatigue Not necessarily imaging confirmed renal colic, Not necessarily imaging confirmed renal colic, but suspected renal colic
Future Directions Analysis of final data 18 month enrollment period Prospective, external validation of risk factors D l t f li i l th f ED Development of clinical pathway for ED patients presenting with suspected renal colic