The preanalytical
phase of the total testing process is complex. It starts with the
perceived need for the test and ends with specimen processing.1
It is not surprising that between 32% and 75% of all testing errors
occur in the preanalytical phase.2
Considering the amount of automation and process
controls that exist in the analytical phase versus those in the
preanalytical phase, it becomes apparent why this is the case. Not all
preanalytical errors cause adverse events, because many of these
”upstream” errors may be caught during “downstream” processes or are minor
enough that, if undetected, they do not impact patient outcomes.2
They often are associated, however, with rework or further investigations,
which result in unnecessary risk to the patient and unjustifiable costs to
the healthcare system.
Preanalytical improvements primarily have centered on
blood specimens, mostly driven by increasing levels of automation and need
for standardization. Urine collection and processing have lagged behind and
represent areas with much opportunity for improvement. Although still
predominantly a manual process, urine testing is currently facing increasing
levels of automation. As a result, in most markets automated urinalysis is
growing faster than automated chemistry (22% growth rate in 2004). The
growth of urine testing is mainly driven by automated microscopy in
developed countries and traditional urine chemistry in developing markets.3
These advances in urine testing and the fact that
urinalysis remains one of the three major in vitro diagnostic
screening tests — after serum chemistry profiles and complete blood counts4
— create the need to take a hard look at the urine testing workflow
and underscore the importance of reducing preanalytical variability.
There are significant opportunities for process
improvements, efficiencies, and cost reductions in the area of urine
testing. Worldwide, healthcare spending on urine testing is approximately
$566 million annually,3 and assuming an effectiveness level of
95%, the estimated global cost of inefficiencies in urine collection,
testing, and analysis is nearly $30 million per year. This figure generates
a new degree of urgency to focus preanalytical improvement efforts on
processes associated with this area of laboratory testing.
The preanalytical phase in urine testing can be
divided into six major subphases shown in Figure 1.
Figure 1. Preanalytical urine specimen workflow.
Each of these subphases contains between two and five
steps, so the average preanalytical urine testing workflow consists of at
least 22 steps. Some of these steps, such as sample collection, can be
subdivided into activities that further complicate the urine preanalytical
testing process.
Urine specimen collection process
Urine specimen collection varies considerably,
depending on the setting in which the specimen is collected. The
variability in how specimens are collected — where, when, and by whom —
results in a wide range of different activities within this
preanalytical step and increases the likelihood of errors. For a urine
specimen requisition in an inpatient setting, the requisition is
provided to the nurse or appropriate healthcare provider on the unit
notifying her of the test order. The healthcare provider gathers the
necessary materials for specimen collection and enters the patient room
at the appropriate time based on the requisition. Subsequent steps
differ depending on the age and status of the patient.
For an adult patient who does not require assistance,
the healthcare provider should give the patient instructions on how to
perform a proper collection (i.e., a midstream, clean catch) and the
required materials to capture the specimen upon voiding. The patient
performs the required cleansing and voids, as appropriate, into the
container provided. For a dipstick test, the healthcare provider may insert
the dipstick into the specimen at the site of collection, and read and
record the results into the patient’s medical record. At that point, the
urine specimen and container may be disposed of in the patient’s bathroom.
These steps for urine collection and handling also may be followed in an
outpatient clinic setting.
For a patient who is bedridden or cannot urinate
independently, a healthcare provider inserts a Foley catheter into the
bladder through the urethra to collect the urine specimen. Alternately,
specimens may be collected directly from a Foley catheter into an evacuated
tube or transferred from syringe into a tube or cup.5 For infants
and small children, a special urine collection bag is adhered to the skin
surrounding the urethral area. Once the collection is completed, the urine
is poured or transferred directly into a collection cup or transferred
directly into an evacuated tube with a transfer straw.5
For a urine test that requires processing by the
laboratory, the healthcare provider should transfer the specimen into a
safe, clean transport container (e.g., a tube) and label the specimen
container at the point of collection. Care should be taken to ensure that
the specimen is labeled correctly at the point of collection and transferred
into a transport container that is also appropriately labeled. Many urine
specimen collection cups are not designed to sustain transport within a
hospital’s pneumatic tube system. Multiple systems are available to enable a
closed transfer of the specimen from the collection cup into a closed,
transport-safe container, including transfer straws and cups with lids that
contain integrated transfer devices. These systems ensure the healthcare
provider’s risk in handling a potentially contaminated specimen is reduced
and there are no opportunities for introducing contaminants into the
specimen during transport.
Preanalytical variables
Common areas of preanalytical variability in
urine testing include patient-related factors, specimen collection,
specimen identification and labeling, specimen transfer and transport,
and specimen processing. Their effect on urine testing is described here
in more detail:
Patient factors : Patient factors
(e.g., diet, medications) can impact various urine test results, such as
color, specific gravity, pH, or clarity, and can cause testing errors.6
For instance, consumption of beets and rhubarb can result in change of urine
color to red. Presence of a high concentration of ascorbic acid in urine has
been linked with false-negative urine glucose and bilirubin dipstick
results. Similarly, tetracycline therapy has been shown to cause
false-negative urine glucose dipstick results.
Specimen collection : Specimen
collection is an important source of preanalytical variability. The
collection method affects the quality of urine specimens and, if selected
properly, decreases the risk of specimen contamination and healthcare
workers’ exposure. For urine culture and sensitivity testing in particular,
use of the midstream, clean-catch method is preferred because it reduces the
incidence of cellular and microbial contamination.5 Appropriate
collection containers or tubes can decrease the possibility of
specimen leakage in transit, particularly in pneumatic tube systems, and
ensure optimal quality and quantity of specimen for analysis. Collection of
unpreserved urine specimens is more likely to result in bacterial overgrowth
if the specimens are not refrigerated, as refrigeration decreases urine
clarity and causes false-positive nitrite and false-negative glucose
results.6 It is also important to avoid introduction of
contaminants during specimen collection. In obtaining pediatric urine
specimens, for example, collecting urine from a diaper can introduce
contamination from the diaper material, which may affect the test result.
Inaccurate labeling of a urine specimen :
Inaccurate labeling of a specimen with patient identification, date and time
of collection, and suboptimal placement of the label can compromise the
laboratory’s ability to process a urine specimen and obtain a correct
result. If not recognized in time, inaccurate patient information can result
in laboratory errors. On the other hand, if recognized before the onset of
testing, it slows the analytical process by requiring either specimen
recollection or further physician approval before analysis, thereby delaying
reporting of results. Improper label placement can lead to misidentification
of the specimen later in the handling and analytical process if the specimen
container lid with the label is removed or if the label does not adhere to
the container during refrigerated conditions.5 As a result, the
primary goals listed in The Joint Commission’s 2010 National Patient Safety
Goals for the Laboratory include the use of at least two patient identifiers
when providing care, treatment, or services and establishing processes for
maintaining a specimen’s identity throughout the preanalytical, analytical,
and post-analytical processes.7
Use of evacuated tubes that can be labeled at the
bedside reduces the risk of identification errors. Misalignment of bar-coded
labels on tubes also can be a source of identification errors, however.
Instrument bar-code readers cannot ”read” the bar codes on misaligned
labels; sometimes it is enough for a label placement to deviate only a
little from the ideal position to present a problem. As a result, the
misaligned label must be removed and replaced with a properly placed label,
which creates the possibility for an identification error to occur.
Transport of urine specimens : Improper
transport of urine specimens can impact sample quality directly. Increased
length of time between specimen collection and analysis, lack of temperature
control, and use of non-preserved specimens that will not be analyzed within
two hours of collection (e.g., samples that come from satellite locations or
are collected during a 24-hour collection) contribute to overgrowth of
bacteria in the specimen. This can, in turn, impact urinalysis, and culture
and sensitivity test results. To prevent this from happening, the College of
American Pathologists’ accreditation program requires examination of
non-preserved, non-refrigerated urine within one to two hours of collection
and defines non-compliance with this standard as a phase II deficiency that
requires immediate and documented improvement before accreditation is
granted.8,9
If a laboratory cannot analyze a non-refrigerated,
non-preserved specimen within the recommended time frame, however, other
acceptable options can ensure optimal specimen quality. One of them is the
use of non-refrigerated, preserved urine specimens that can be analyzed up
to 48 hours after collection for culture and sensitivity and up to 72 hours
for urinalysis (manufacturers’ recommendations should be reviewed for
product-specific guidance).10 Clinical and Laboratory Standards
Institute (CLSI) recommends that refrigerated, unpreserved specimens be
maintained at 2^0C to 8^0C. When preparing for analysis, it becomes equally
important to allow refrigerated specimens to return to room temperature in
order to enable temperature-dependent enzymatic reactions to occur during
analysis6 and to prevent any false signals from crystals formed
during refrigeration. When preserving specimens for transport and analysis,
use of an evacuated container helps to ensure that the proper preservative:
specimen ratio is adhered to, because evacuated tubes are designed to draw a
specific sample volume.5
Specimen processing : Variables in
specimen processing, such as centrifugation, impact the quality of results.
Variation of speed and time can change the cellular elements obtained in the
sediment.
Additional factors : The chronic
struggle of laboratories to address ongoing labor shortages, budget
reductions, and increasing test volumes within their own walls can impact
the quality of the results the laboratory is able to generate and the
revenue or reimbursement that the laboratory is able to capture.
Specifically, high turnover and lack of training and education on how to
properly collect and handle urine specimens can result in higher specimen
contamination rates.
Opportunities for preanalytical process improvement
The various methods through which a urine
specimen can be obtained and their manual nature can contribute
significantly to preanalytical errors. The fact that many of the steps
in the preanalytical phase are performed outside the walls of the
laboratory and often by personnel not managed by the laboratory creates
further challenges for the laboratory in controlling the steps that
contribute to preanalytical variability. The laboratory is often
accountable for the outcome (clinical and financial) of this phase and
for resolving — if not overcoming — the preanalytical challenges. At the
same time, clinical laboratories are constantly faced with pressures to
continually increase productivity, lower costs, and improve quality. To
address these challenges, the laboratories can use several
cost-effective tools designed to standardize and optimize urine
collection and handling and positively impact the quality of urine
specimen results.
Application of LEAN management methodologies
: To meet the increasing pressures that the clinical laboratories are
currently facing, many laboratory administrators and pathologists are faced
with the fact that radical increases in quality, productivity, and error
reduction cannot be achieved using the traditional management models. ”By
contrast, the pioneering laboratories in the United States that use LEAN and
Six Sigma to redesign workflow in their high-volume core chemistry and
hematology labs found that these quality management systems — in a 12- to
16-week project —could lead to a 50% reduction in average test turnaround
time for a hospital lab, a 40% to 50% improvement in labor productivity and
a comparable improvement in quality of results.11 When
considering the more highly manual processes involved in urine specimen
collection and handling, one also could hope to achieve similar benefits
from application of LEAN and Six Sigma principles to the urine collection,
handling, and processing areas. LEAN management centers on reducing waste
and offers a set of tools that do not require significant capital
investments to be effective and can have immediate and recognizable impact
when applied properly. Six Sigma is a metric and a methodology that focuses
on reducing variability (i.e., counting and decreasing the number of defects
in a process). A process that performs at a Six Sigma level realizes defects
at a rate of 3.4 occurrences per million opportunities. Used in combination
with LEAN tools, Six Sigma methodology can enable an organization to monitor
and improve its quality performance based on the elimination of errors where
possible (i.e., LEAN) and reduce or manage them in parts of a process that
cannot be eliminated (i.e., Six Sigma). For the purposes of this discussion,
we focus specifically on the application of LEAN principles to the
preanalytical process in urine specimen collection.
Simply put, the fundamental principles of LEAN
management emphasize reduction of unnecessary and non-value-added activities
to reduce total production time and effort. LEAN tools focus on identifying
steps that are error prone and must be controlled if they cannot be
eliminated altogether. LEAN management principles challenge doing things the
way they always have been done in favor of simplified and standardized
methods of performing tasks that support getting things done right the first
time with minimal wasted time and effort. One highly effective tool in
applying LEAN thinking is the process map, which is constructed by recording
all steps in a current process or subprocess and illustrating the current
state (i.e., ”as is”). LEAN tools, such as process mapping, enable
organizations to take a critical inventory of the activities taking place
within their laboratories and activities external to the clinical laboratory
but relevant to testing processes. Armed with knowledge of what is actually
taking place, as represented by a process map, laboratory management is
better equipped to identify how the process should look (i.e., the ”to be”
process) in order to obtain better and more productive outcomes.
”To be” processes are streamlined processes that
are flexible, reduce waste, optimize the process, improve process control,
and improve use of resources. For the clinical laboratory, improved use of
limited resources is a continuous quest, and the benefits to the laboratory
of application of process mapping and LEAN thinking becomes clear. Figure 2
provides a simplified example of a current state process workflow analysis,
focused on the subprocess within the laboratory from urine specimen
accessioning to specimen disposal, at a hospital before a LEAN workflow
implementation. All of the major process steps are captured, regardless of
whether they support good practice or whether they represent value-added
activities or contribute to delays in providing results. Steps that
represent potential for error and steps that do not contribute value to the
target end product, or result, but consume time or resources are indicated
as such.
Figure 2. This process map shows 17 steps for urine specimen
transport and handling in the laboratory; 11 steps can be eliminated to
implement a LEAN process.
The Xs in Figure 2 illustrate the impact of applying
LEAN management principles to the urine specimen collection and handling
process shown. Non-value-added or error-prone steps are either removed or
controlled in the revised process, resulting in a more efficient, timely,
and standardized process. Specifically, by changing the method of urine
specimen collection, 11 steps were removed from the process. All three of
the error-prone steps were eliminated, two of them in the preanalytical
phase, including the open transfer of specimens into tubes from cups and the
relabeling of specimens. This change created a safer environment for the
laboratory staff and decreased the risk of testing errors for the patient.
Five non-value-added steps were eliminated, three from the preanalytical
phase, which increased the efficiency and reduced the waste of the
laboratory staff and materials. Overall, the eliminated steps represented
64% of all steps in the process.
This example illustrates how the use of a simple
tool, which does not require significant capital investment to execute, can
lead to visible quality improvements by simplifying the preanalytical
process in the lab and eliminate opportunities for errors.
Additional LEAN tools, such as value-stream mapping,
also can be applied. This tool determines the amount of time taken for
completion of the entire process, as well as each step in a process flow,
and categorizes those activities into value-added and non-value-added
activities. The total time to perform value-added and non-value-added
activities is then quantified in the pre- and post-LEAN implementation flow
charts. The reduction in non-value-added time can be quantified as potential
savings based on the wage data of laboratory and other hospital personnel
involved in performing those steps. Based on the resulting total time
indicated from collection to analysis, tools and products can be applied to
the new process flow, such as the introduction of tubes with urine
preservative. For example, if unpreserved, unrefrigerated urine specimens
are not analyzed within two hours of collection, then the laboratory can
further reduce its specimen errors and improve quality of results in the
first attempt by refrigerating the specimen at 2^0C to 8^0C or preserving
specimens until the specimen can be analyzed appropriately.10
Additional tools : Additional tools are
available to aid in standardizing work across various collection settings
and among various individuals involved in performing urine collections.
Devices : Devices are available to
provide further support to the laboratory in ensuring quality urine
specimens. In manual and automated analytical settings, urine containers
with preservative enable the laboratory to balance the flow of specimens
requiring analysis that come into the laboratory with the available
resources to complete the analysis in a timely manner. For organizations
that currently face staffing challenges without adequate volume to justify
automation, using preservatives with urine specimens enables the analytical
workload to be balanced over the peaks and troughs during a longer time
frame — up to 72 hours for urinalysis and up to 48 hours for culture and
sensitivity testing — without refrigerating specimens.
Closed systems for transfer and transport of
specimens :
Closed systems reduce the risk of exposure of healthcare workers to
contaminated specimens and the exposure of specimens to contaminants during
transfer and transport. Amber-colored urine containers protect specimens
from light sensitivity for certain urine tests (e.g., bilirubin).
Instructions for clean, midstream catch :
Instructions posted in areas where patients are voiding into urine
containers — translated to languages other than English, if necessary — can
reduce the risk of contamination of specimens and mitigate insufficient
training caused by high turnover in staff.
Impact of preanalytical process workflow on automation
Opportunities for automation of urine specimen
analysis continue to improve, including the ability to perform
urinalysis and microscopy of urine sediment on a single platform.
Further opportunities include autoverification of results, which can
eliminate the need for medical technologists to review thousands of
normal test results before releasing them. Automation of urinalysis
enables the clinical laboratories to absorb substantial volume increases
without adding staff.
Implementation of automation without improvement of
the preceding preanalytical processes often creates a new set of issues for
the laboratory to resolve. Experience shows that automating a bad process
only serves to speed up problems, and potentially magnifies the problem and
its associated cost. The value of investing effort in streamlining or
redesigning current preanalytical processes before implementation of
automation should not be underestimated. LEAN management and Six Sigma are
only two examples of quality-management methods that can be used to improve
processes before investing in automation.
Business case for preanalytical process improvement
Before determining the appropriate steps that
will lead to the reduction of preanalytical variability in urine
specimen collection and handling, an institution must understand what
factors impact the preanalytical phase of urine testing the most, in
order to determine the true causes for preanalytical errors and apply
the right solutions to get optimal results the first time.
The business case for reducing preanalytical
variables can be as simple as measuring the number of urine tests that do
not get reimbursed because of preanalytical quality issues, such as urine
culture contamination or urine bacterial overgrowth. At its most
conservative, the lowest urine test reimbursement rate could be used, such
as the Medicare rate for manual urinalysis without microscopy. At the higher
end, the Medicare reimbursement for urine bacterial culture could be used.12
These figures represent the billable charges that a laboratory could capture
but did not because of lack of a result. This does not begin to factor in
the lost productivity of employees who are already challenged in a
resource-constrained laboratory environment. Whether viewed as a revenue
opportunity or a cost-avoidance opportunity, a laboratory can do a simple
calculation to qualify the value of controlling preanalytical variability.
Simple principles such as LEAN — eliminating
unnecessary activities and getting it right the first time — can be applied
easily without sophisticated technology when the right focus and tools are
applied. Given the pressures prevalent in the modern laboratory environment,
laboratory management cannot afford to ignore the options available to
control processes, drive efficiencies, and gain improved charge capture for
urine specimens.
Primary constraints that laboratories currently face
are personnel shortages and lack of financial resources. The business case
for quality improvement is a critical component for justifying the resources
required to implement change in the preanalytical process. Fortunately for
laboratorians, cost-effective external resources are available to conduct
the required analyses to identify an organization’s specific areas for
improvement and implement the required changes and process controls.
Laboratory success stories exist that support the cost justifications to
pursue quality improvement, whether through LEAN and Six Sigma applications,
use of readily available devices, or other similar approaches.
Summary
In the past, laboratories have addressed issues
of preanalytical variability in an opportunistic way, addressing
discrete parts of the preanalytical process, such as patient
identification, specimen rejection, and blood/urine culture
contamination. To obtain needed quality improvements and error
reduction, it is necessary to look at the preanalytical process as a
whole — from test ordering to the moment the specimen is processed by
the analyzer and apply process improvement methodologies, such as LEAN
and Six Sigma. To achieve this, laboratories should map the
preanalytical phase in its entirety, identify steps that are potential
causes of unnecessary variability that lead can to laboratory errors,
and find ways either to remove them or error proof them. At the same
time, by using this approach it is possible to reduce unnecessary waste
and obtain needed process efficiencies.
The authors — Ana K. Stankovic, MD, PhD, MSPH,
Medical and Clinical Affairs, and Elizabeth DiLauri, MBA, Alternate
Specimen Management — work with BD Diagnostics, Preanalytical Systems in
Franklin Lakes, NJ. The views expressed in this article are those of the
authors and not of Becton, Dickinson and Company.
Reprinted from Clinics in Laboratory Medicine, Vol. 28/Issue 2; Ana
K. Stanovic, MD, PhD, MSPH, and Elizabeth DiLauri, MBA; Quality Improvement
in the Preanalytical Phase: Focus on Urine Specimen Workflow/pp. 339-350;
Copyright 2008, with permission from Elsevier.
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