Analysis of Turnaround Time by Subdividing Three Phases for Outpatient Chemistry Specimens

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1 144 Available online at Annals of Clinical & Laboratory Science, vol. 39, no. 2, 2009 Analysis of Turnaround Time by Subdividing Three Phases for Outpatient Chemistry Specimens Hee-Jung Chung, 1 Woochang Lee, 1 Sail Chun, 1 Hae-Il Park, 2 and Won-Ki Min 1 1 Department of Laboratory Medicine, University of Ulsan College of Medicine, and Asan Medical Center, Seoul; 2 Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, South Korea Abstract. The Department of Laboratory Medicine at Asan Medical Center provides a special one-stop service to allow both doctors and outpatients to receive routine outpatient test results in a timely manner within 1 hr. We developed a new Laboratory Information System (LIS)-based monitoring system that records the laboratory turnaround time (TAT) in 3 phases and analyzes the time to complete each phase with relevant specimens. TAT is subdivided into preanalytical, analytical, and postanalytical phases based on the 4 time points when data are entered automatically into the LIS. The average TAT for 13,594 outpatient routine chemistry specimens with the one-stop service was 43.6±7.7 min. Completion times of the preanalytical, analytical, and postanalytical phases were 29.7±6.9, 13.9±4.1, and 0.02±0.13 min, respectively; 98.0% of the specimens were reported within 60 min. The remaining 2.0% were reported after 60 min with an average TAT of 68.7±11.3 min. Preanalytical phase delays were primarily responsible for the specimens reported between 60 and 90 min, and analytical phase delays were largely responsible for the few specimens (0.2%) reported after 90 min. For specimens reported between 60 and 90 min, the preanalytical phase was found to need improvement in order to shorten TAT; the main target for improvement was identified as the waiting time for phlebotomy step. Keywords: automation, clinical laboratory service, laboratory test turnaround time Introduction The laboratory turnaround time can be defined differently according to the test type (stat vs routine), analyte, and institution. It is commonly defined as the time from when a test is ordered until the result is reported [1]. The Department of Laboratory Medicine at Asan Medical Center defines the laboratory turnaround time (TAT) for outpatients as the time taken from printing a barcode to reporting the test result. Address correspondence to Won-Ki Min, M.D., Ph.D., Department of Laboratory Medicine, University of Ulsan College of Medicine and Asan Medical Center, Pungnap-2dong, Songpa-gu, Seoul , Republic of Korea; tel ; fax: ; wkmin@amc.seoul.kr. Asan Medical Center is a 2,200-bed tertiary care teaching hospital that receives 8,000 outpatients every day. The Department of Laboratory Medicine performed 30 million tests in The department offers an expedited one-stop service to outpatients for routine chemistry, hematology, diabetes, coagulation, urinalysis, and stat tests. The one-stop service aims to allow doctors and outpatients to receive test results in a timely manner within 1 hr. We reported previously that the percentages of outpatient specimen results reported within 60 min for routine hematology, chemistry, urinalyses, coagulation, and diabetes tests were 80.1, 91.9, 99.5, 92.6, and 97.6%, respectively [2]. Traditionally, laboratory TAT is determined by the timely progress of 3 phases of testing: preanalytical, analytical, and postanalytical [3,4]. Smellie et al [5] assessed the TAT based on the /09/ $ by the Association of Clinical Scientists, Inc.

2 Analysis of three phases of laboratory turnaround time 145 timeliness of these individual phases by manual records, but there have been no previous reports of the use of a laboratory information system (LIS) to record and analyze TAT. Therefore, we designed a new LIS that records TAT data automatically and analyzes the time taken for the 3 phases that comprise the total laboratory TAT for each test. Materials and Methods This study utilized 13,594 outpatient specimens that were received from 8:00 a.m. until 5:00 p.m. at Asan Medical Center for routine one stop chemistry tests between 30 July 2007 and 26 August Various automated instruments were used for specimen testing: three TBA 200FR (Toshiba Medical System Co., Tokyo Japan), two TBA 200FRNeo (Toshiba), three COBAS Integra 800 (Roche Diagnostics, Basel, Switzerland), and four Synchron LX 20 (Beckman Co., Fullerton, CA, USA). A total of 207,143 tests were performed; the 30 routine chemistry analytes were plasma total calcium, glucose, creatinine, uric acid, cholesterol, protein, albumin, AST, ALT, ALP, total bilirubin, direct bilirubin, phosphorous, urea, gamma-glutamyl transferase, sodium, potassium, chloride, total CO 2, amylase, lactate dehydrogenase, triglyceride, HLD-cholesterol, LDL-cholesterol, C-reactive protein, magnesium, lipase, CK, iron, and TIBC. A program was developed to record and manage the time points entered into the LIS, the time taken to fulfill each phase, the testing instruments, the operators, retesting, and verification, such as delta value, panic value, and critical value checking. During laboratory test processing at Asan Medical Center, 4 time points were automatically recorded in LIS: ie, barcode printing when the barcode was printed by an autolabeler and the specimen was accessed simultaneously; scanning when the barcode was scanned in the autoanalyzer; result to LIS when the result was transmitted from the instrument to the LIS after the analysis; and result to HIS when the verified result was transmitted from the LIS to the hospital information system (HIS). In this study, the TAT was classified into 3 phases on the basis of these 4 time points, ie, preanalytical phase (barcode printing scanning), analytical phase (scanning result to LIS), and postanalytical phase (result to LIS report to HIS) (Fig. 1). The preanalytical phase consists of the following steps: barcode printing with simultaneous specimen accession; the wait for phlebotomy; phlebotomy; transport of the specimen from the blood-collection site to the laboratory via a conveyer belt; manual centrifugation; manual specimen loading on an autoanalyzer; and barcode scanning in the autoanalyzer. The analytical phase occurs in the autoanalyzer and consists of the following steps: barcode scanning; order retrieval from the LIS; analysis; and the result is sent to the LIS. The postanalytical phase consists of the following steps: the result is received by the LIS; verification (automatic or manual); and the report is sent to the HIS. The mean TAT, standard deviation (SD), proportion of acceptable tests (% of TAT within 60 min), 90th percentile, 95th percentile, and 99th percentile of TAT were evaluated for the 13,594 specimens. The specimens were divided into 3 groups; TAT within 60 min, TAT between 60 and 90 min, and TAT after 90 min. The average time taken to fulfill each phase was measured, and the contribution of each phase to Table 1. Mean and proportion of overall TAT in each group: the TAT within 60 min; the TAT between 60 and 90 min; and the TAT greater than 90 min. Group Specimens Specimens reported Overall TAT no. (%) after 60 min (%) (min, mean ± SD)* Specimens reported within 60 min 13,328 (98.0%) 43.1±6.7 Specimens reported after 60 min 266 (2.0%) 100.0% 68.7±11.3 Specimens reported between 60 and 90 min 238 (1.8%) 89.5% 65.3±5.8 [+22.2] Specimens reported after 90 min 28 (0.2%) 10.5% 96.9±4.9 [+53.8] All one-stop service specimens 13,594 (100%) 2.0% 43.6±7.7 * The mean TAT duration that exceeded the TAT of specimens reported within 60 min is enclosed in brackets. Table 2. Mean TAT of each phase, according to their groups. Group Preanalytical Analytical phase Postanalytical phase of TAT (min)* of TAT (min)* phase of TAT (min)* Specimens reported within 60 min Specimens reported between 60 and 90 min 42.9 [+13.5] 22.4 [+8.7] 0.02 [+0.00] Specimens reported after 90 min 35.5 [+6.1] 61.4 [+47.7] 0.02 [+0.00] * The mean TAT duration that exceeded the TAT of specimens reported within 60 min is enclosed in brackets.

3 146 Annals of Clinical & Laboratory Science, vol. 39, no. 2, 2009 Fig. 1. Laboratory flow of the one-stop service specimens at Asan Medical Center. Fig. 2. Histograms showing the distribution of TAT: (A. upper left panel) overall TAT; (B. upper right panel) preanalytical TAT; (C. lower left panel) analytical TAT; (D. lower right panel) postanalytical TAT.

4 Analysis of three phases of laboratory turnaround time 147 Fig. 3. Percentage of each phase according to group: (A. left) specimens reported within 60 min; (B. center) specimens reported between 60 and 90 min; (C. right) specimens reported after 90 min. the overall TAT was calculated. When specimen results were reported after 60 min, each phase was investigated to determine the underlying reason for the lack of timeliness. Statistical software SPSS (version 13.5, SPSS Inc., Chicago, IL, USA) was used for data analysis. Results Overall TAT and TAT of the 3 phases. Fig. 2 shows the distribution of TAT of the 13,594 specimens. The average TAT was 43.6±7.7 min; 98.0% of specimens were reported within 60 min, and the time to 90th percentile of TAT was 51.8 min. The times taken to complete each of the 3 phases (preanalytical, analytical, and postanalytical) were 29.7±6.9, 13.9±4.1, and 0.02±0.13 min, respectively (Table 1). The preanalytical, analytical, and postanalytical phases accounted for 68.1%, 31.9%, and 0.05% of overall TAT, respectively. Specimens reported within 60 min. Specimen results that were reported within 60 min accounted for 98.0% (13,328/13,594) of the specimens tested, and the average TAT was 43.1±6.7 min. The times taken to complete the phases were as follows: preanalytical, 29.4±6.1 min; analytical, 13.7±3.0 min; and postanalytical, 0.02±0.13 min (Table 1). These phases accounted for 68.2% (preanalytical), 31.8% (analytical), and 0.05% (postanalytical) of the TAT, respectively (Fig. 3A). Specimens reported after 60 min. The results of analysis that were reported after 60 min accounted for 2.0% (266/13,594) of the tested specimens; the average TAT was 68.7±11.3 min. Test results reported between 60 and 90 min accounted for 89.5% (238/266) of the specimens reported after 60 min, and results from analyses reported after 90 min accounted for the remaining 10.5% (28/266). TATs of the specimens reported between 60 and 90 min and after 90 min were 65.3±5.8 and 96.9±4.9 min, respectively (Table 1, Fig. 3B and 3C). For specimen testing results reported between 60 and 90 min, the TAT of the preanalytical, analytical, and postanalytical phases was longer than those of the standard specimens by as much as 13.5, 8.7, and 0.0 min, respectively. The root cause of the prolonged preanalytical phase was the waiting time for phlebotomy (barcode printing/ phlebotomy) and the waiting time for analysis (specimen loading/barcode scanning) In the case of specimens reported after more than 90 min, the TAT of the three phases was longer than those of the standard specimens by as much as 6.1, 47.7, and 0.0 min, respectively (Table 2). The root cause of the prolonged analytical phase was repeated tests. Discussion During the present study period, a total of 85,221 specimens were referred to the Department of Laboratory Medicine. Inpatient specimens accounted for 47.9% (40,840) and outpatient and quality control specimens accounted for 47.9% (40,794) and 4.2% (3,587) of the total specimens, respectively. Specifically, 13,594 specimens were subjected to the one-stop service testing, and this accounted for 33.3% of outpatient specimens (13,594/40,794) received. Thus, the expedited onestop service was utilized by many outpatients.

5 148 Annals of Clinical & Laboratory Science, vol. 39, no. 2, 2009 In a 1998 CAP Q-Probes Study, 41.1% of laboratories defined emergency department (ED) TAT as the time taken from receipt of a specimen in the laboratory to reporting of the test result, 27.0% defined it as the time taken from the test order to reporting of the result, and 18.2% defined it as the time taken from collecting a specimen to reporting the result [6]. Nevertheless, 40.2% of clinicians answered that ED TAT starts from the time of the physician s test request [6]. Hence, laboratories and clinicians maintained wide differences of opinion concerning laboratory TAT. Furthermore, there have been no previous studies related to laboratory TAT from the standpoint of the patients. The maximal TAT should be calculated from the time at which a patient enters the blood collection site. Accordingly, in the Asan Medical Center, laboratory TAT starts from barcode printing to reflect the maximal TAT from the standpoint of the patients. This does not include the time interval for receiving patients, which takes approximately 2 min. Asan Medical Center gives priority to emergency specimens followed by the one-stop service specimens. A 2004 CAP Q-Probes study reported that the 90th percentile of order-to-report TAT for CK-MB was 66.5 min and that of troponin was 61.0 min for ED specimens [7]. In our analysis, the 90th percentile of overall TAT (barcode printing to report) for the one-stop service specimens was 51.8 min. Many researchers have reported various methods to shorten laboratory TAT [8-15]. Lewandrowski et al [13] reported that TAT can be shortened by running a satellite laboratory. Fernandes et al [10] reported that the time taken to convey specimens can be shortened by using a pneumatic tube system. Steindel et al [14] analyzed TAT outliers that caused delays. As reported previously, this laboratory has introduced various systems to shorten the TAT of outpatient testing [2] and has established the present system. First, this laboratory runs a separate satellite laboratory for outpatient testing. Second, a continuous conveyor belt has been set up between the blood collection site and the outpatient laboratory so that specimens can be relayed automatically to the outpatient laboratory after phlebotomy. Third, similar to the report of Steindel et al [14], a realtime TAT monitoring system was developed whereby TAT can be investigated based on TAT outliers, sample reference time, or test items. Fourth, aside from the methods reported by other researchers, this system was arranged so that specimens can be accepted simultaneously after the autolabeler prints a barcode, which saves labor and time. Fifth, a Priority System for Specimens was set up so that the one-stop service specimens can be selected from among outpatient specimens, and their results can be reported within 1 hr. Finally, for outpatient specimens, clotting time was saved by using plasma separating tubes. The subdivided TAT monitoring system developed here is based on the 4 time points recorded automatically in the LIS. We devised an additional output sheet on the LIS to show the TAT of each phase with integrated information, such as the ID of the tested autoanalyzer, whether it was retested or diluted, the method of dilution (manual or auto), and verification (delta, panic, and critical value checks). Consequently, the three phases (preanalytical, analytical, and postanalytical phases) that were applied to this TAT monitoring system are different from previous systems [16,17]. The analytical phase was fixed according to the test items of each instrument, because the variable waiting time for analysis (specimen loading barcode scanning) was excluded. The Toshiba autoanalyzers used in this hospital take 12.9 to 14.2 min to perform analyses, depending on the test items. The Synchron LX 20 autoanalyzers take 12.7 to 21.8 min, and the COBAS Integra 800 autoanalyzers take 13.5 to 20.2 min. In the preanalytical phase (Fig. 1), phlebotomy takes an average of 1 min, 30 sec, per patient, and tube preparation time can be reduced by using an autolabeler. The transport step takes 2 min, 20 sec, to 4 min, 20 sec, depending on where the blood specimen is placed on the conveyor belt. The centrifugation step is performed by 2 staff members using 5 Union 5KR centrifuges (Hanil Science Industrial Co., Seoul, Korea); it can be completed routinely within 14 min, including a waiting time of 4 min. The preanalytical phase was markedly affected by these 2 variable steps: waiting time for phlebotomy (barcode printing phlebotomy) and

6 Analysis of three phases of laboratory turnaround time 149 waiting time for analysis (specimen loading barcode scanning). In particular, the waiting time for phlebotomy took 7.3±4.3 min, and this step accounted for 24.8% of the preanalytical phase in our further investigation over a 2-wk period. The waiting time for phlebotomy could easily be shortened by increasing the numbers of phlebotomy desks and relevant staff. Hence, 2 more blood collection sites are scheduled to open in addition to the existing site to shorten patients waiting time for phlebotomy. The preanalytical TAT of specimens reported after 60 min took 12.8 min longer than that of specimens reported within 60 min. Hence, it appears that improvement of the preanalytical phase (especially waiting time for phlebotomy) would significantly decrease the TAT. The time spent waiting for analysis could not be measured using the current system. To reduce waiting time for analysis, this hospital laboratory uses multiple autoanalyzers and prioritizes specimens for the one-stop service. Manor [18] and Rollo et al [19] reported that non-analytical delays, such as transporting and reporting delays, are the main causes of lagging laboratory TAT. The 0.2% of specimens that were reported after 90 min comprised only 28 specimens. For one specimen from a child, the preanalytical phase took 72.4 min due to difficulty in blood collection. In another 20 specimens, retests had to be performed, which resulted in delays. In this group, the preanalytical and analytical phases accounted for 36.6 and 63.4% of overall TAT, respectively. In summary, we subdivided laboratory TAT into 3 phases, preanalytical, analytical, and postanalytical, which were applied to one-stop outpatient specimens. In the majority of specimens (98.0%) test results were reported within 60 min, and only 2.0% of specimens were delayed. 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