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Worried that your laboratory doesn't measure up?

After reading the article "Inaccurate Doses of Rh Immune Globulin After Rh-Incompatible Fetomaternal Hemorrhage: Survey of Laboratory Practice," were you immediately concerned about the findings? The frequency (20%-30%) with which patients in the 21st century would have received an underdose during rhesus (Rh) immune globulin (RhIG) therapy (1) should be nothing short of shocking to pathologists and clinicians alike. It should serve as a "wake-up call" that there is much room for improvement in this area and perhaps with any process requiring manual calculations. In today's world of ever-tightening budgets, diminishing pools of medical technologists, and expanding responsibilities for staff, it is our job as administrators and managers to hand our employees the tools that will enable them to perform their jobs in a way that reduces errors and enhances patient care.

The report demonstrates the inherent risk of calculation errors in situations in which a formula is used manually to calculate therapeutic doses. Since first coming to the US market in 1968, RhIG therapy has become a standard of care for the prevention of hemolytic disease of the fetus and newborn (HDFN) (2) and has been primarily responsible for the dramatic reduction in the mortality from this disease. (3) Shortly after the introduction of RhIG, the rate of Rh(D) HDFN dropped from an estimated 45:10 000 to 20.6:10 000 births. (4) In 1991, it was shown that antenatal prophylaxis reduces the incidence of anti-D alloimmunization (0.1%-1.8%),5 but the rates have not continued to decline.

In 2003, the US National Center for Health Statistics published data on demographically variable Rh(D) sensitization and reported a rate of 6.8 cases of Rh(D) alloimmunization per 1000 live births (0.68%). (6) With more than 4.1 million births per year, (7) the Unites States reports approximately 28 000 cases of rhesus alloimmunization annually. Failure to prevent Rh(D) alloimmunization has several root causes, (1) but underdosing of RhIG because of a calculation error should never be one of them. In response to the frequency of misdosing mishaps with RhIG, as reported in the College of American Pathologists (CAP) proficiency surveys--and presumably after the committee's realization that all too few tools were generally available--the CAP Transfusion Medicine Resource Committee developed a freely downloadable spreadsheet calculator based on Microsoft Excel (Redmond, Washington) (; found under References and Resources/ Clinical Pathology/Transfusion Medicine/Resources/ RhIG Dose Calculator; accessed October 20, 2008).

In general, is the necessary equipment (eg, personal computers [PCs], programmable calculators, job aids, or hospital or laboratory information systems with the capability to perform programmable calculations) available for clinical care staff to treat patients effectively in your hospital? The simplest solution would be to use functionality already present in a corporate information system, if available. Fortunately, newer hospital and laboratory information systems allow greater functionality, hospitalwide integration and access, and automation of calculations that bypass traditionally manual steps. (8) The need for additional calculations after a laboratory result is obtained is not limited to RhIG dosing or the blood bank. For example, estimating the glomerular filtration rate for some patients is complicated and may require the use of several equations and several laboratory results to meet all of the patient's needs. (9,10) Older information systems may not be able to perform result-based calculations or may do so only after additional patches and/or complicated programs are installed.

See also p 465.

In the absence of automated solutions in the corporate information system, other solutions can be used. There is an increasing interest and need to adopt best practices, (11) including initiatives such as the US Biovigilance Network (12) and the Joint Commission's interest in Blood Management Performance Measures. (13) Although calculations and other imbedded logic are making their way into health care information systems, few have made their way into routine laboratory practice, for a variety of reasons. (14) Third-party resources, therefore, will likely serve a needed function in helping laboratories work around the limits of their information systems to improve patient outcomes, reduce waste, and decrease errors. This editorial seeks to dispel, or at least to acknowledge, some of the obstacles that may prevent laboratories from using third-party tools for calculations, such as a PC-based programmable calculator. There are several likely obstacles that supervisors and staff will face, including potential technologic or logistic hurdles and validation requirements.


Let's face it, many laboratorians are simply not comfortable using third-party job aids and applications such as Microsoft Excel for operational issues beyond budgeting and administrative reports. A common reaction to using spreadsheets in the laboratory may be something along the lines of "my staff already has too much to do ... I can't think of adding another thing for them to learn ... besides, they do not even like spreadsheets and can perform the calculations just fine by using a calculator. ..." The author of the report cited previously (1) demonstrates quite effectively that the last point is not entirely correct. How many more laboratories would have failed to appropriately calculate RhIG doses if every staff member had been asked to perform the calculations?

Laboratory staff members are required to learn all manner of new techniques, technologies, and computer systems to keep up with changing processes and technologic advances. They can learn to use any tool, if properly trained. A mini-tutorial or job aid that gives a "walkthrough" of the tool's application would be very helpful. Administration of RhIG is relatively safe, but not without side effects. (15) Accounting for the number of vials of RhIG, the dollars saved per year, and the number of patients receiving correct dosages should be enough to convince your administrative office to purchase outside training software if none is available inside your institution. If not, the needs of a whole laboratory, seeking cost- or time-saving measures, can be used to justify your request.

Do not underestimate the power of the spreadsheet alone in making an impact on your laboratory's operations. After being exposed to the use of spreadsheets, the laboratory staff can use other published spreadsheet tools16 or create its own tools to perform additional tasks, such as standardizing repetitive calculations or scanning bar code blood unit numbers to prevent typographic errors. Spreadsheets also have more advanced features, which can be set up to flag suspect entries or abnormal results. The use of spreadsheets as part of general operations, and not just as a budgeting tool, has had a very positive impact in the authors' institution, eliminating variation in approaches to calculation, greatly reducing errors, speeding up the analysis of data, and enhancing the appearance and clarity of the resulting records. The investment in technology, training, and validation is easily justified.


A laboratory without a PC made readily accessible to the staff will find it difficult to implement software-based tools that are not already part of its hospital or laboratory information systems. Institutional policies may also make it difficult to get access to the appropriate software tools. While staff may not have access to PCs at their workstation, one PC could be placed in a readily accessible part of the laboratory. Such access is increasingly necessary to use corporate applications such as e-mail and electronic medical records. Hopefully, the lack of a computer is no longer an obstacle to using PC-based or Internet-based tools. In the authors' opinion, restricting frontline staff from accessing a PC because of perceived concerns about computer viruses, the viewing of unacceptable Web sites, or the potential for playing online games, undervalues laboratory professionals and will hinder efforts to retain Internet-savvy, younger staff members who have grown up learning about and working with computers.


You validated your new piece of automated testing equipment and your new refrigerator and temperature monitoring system, and you did so successfully. But a third-party software solution such as a spreadsheet? The validation process is straightforward. Validation is essentially a confidence-building exercise, but its formal definition can be found in a number of resources. (17) Other resources discuss the validation processes in much greater detail. (18,19) There can be a number of reasons for performing a validation, driven by regulatory, business, legal, or clinical requirements. Transfusion Services should be familiar with Clinical Laboratory Improvement Amendments, CAP, and US Food and Drug Administration expectations for validation, just to name a few. At the 50 000-foot level of commitment, a validation consists of the following:

* A description of the intended use of the item

* An inventory of requirements

* A list of tasks that will establish if the item performs as expected

* An analysis of things that might go wrong with the use of the item and how to mitigate or control these risks

As an example, consider the CAP's RhIG dose calculator. An individual should take no more than 2 to 4 hours to complete the validation, including finding cases to help validate the calculations. After applying some critical thinking to the problem, the authors of this editorial rapidly assembled a straightforward approach for validating this simple spreadsheet tool. The basic tasks needed to establish the validity of this tool can be broken down into 4 steps.

* Have someone familiar with Excel review the formulas in the spreadsheet against the calculations in the technical manual. A quick review will confirm that they match.

* Pick a few sets of data, real or artificial, and show that the application gives the same result as a correctly performed manual calculation.

* Verify that the spreadsheet is locked and protected (it is), such that formulas cannot be changed without unprotecting the spreadsheet. For greater protection, you might consider adding a password that would be required to unprotect the worksheet.

* To mitigate input error potential, consider establishing a standard procedure requiring personnel to print and verify their entries with each use.


Laboratory managers and supervisors commonly complain that they lack the additional resources to implement changes or new technologies, yet are increasingly required to justify dollars spent on health care. (20) Publications, including the Institute of Medicine's To Err is Human, (21) point out the preventable errors in the health care system that impact patient safety. To improve patient safety, some systemwide changes will be required to how health care is currently delivered. Not all fixes, however, will require such drastic changes. (22) Third-party, PC-based software solutions provide simple, inexpensive tools that can improve accuracy, tracking/trending, and consistency while decreasing manual calculations, preventable errors, and procedural complexity when local information systems lack the necessary functionality. Tools such as the CAP's RhIG dose calculator would appear to offer a pragmatic solution, offering uniform interpretation, accurate calculation, and readily printable or electronic documentation of the input data and results.

Accepted for publication November 10, 2008.


(1.) Ramsey G; for the College of American Pathologists Transfusion Medicine Resource Committee. Inaccurate doses of Rh immune globulin after Rh-incompatible fetomaternal hemorrhage: survey of laboratory practice. Arch Pathol Lab Med. 2009;133(3):465-469.

(2.) American College of Obstetrics and Gynecology, Committee on Practice Bulletins-Obstetrics. ACOG practice bulletin. Prevention of Rh D alloimmunization. Int J Gynaecol Obstet. 1999;66:63-70.

(3.) Joseph K, Kramer M. The decline of Rh hemolytic disease: should Rh prophylaxis get all the credit? Am J Public Health. 1998;88:209-215.

(4.) Chavez GF, Mulinare J, Edmonds LD. Epidemiology of Rh haemolytic disease of the newborn in the United States. JAMA. 1991;265:3270-3274.

(5.) Bowman JM. Antenatal suppression of Rh alloimmunization. Clin Obstet Gynecol. 1991;34(2):296-303.

(6.) Martin JA, Hamilton BE, Sutton PD. Ventura SJ, Menacker F, Munson ML. Births: final data for 2003. Natl Vital Stat Rep. 2005;54(2):1-116.

(7.) Martin JA, Hamilton BE, Sutton PD, et al; for the Centers for Disease Control and Prevention National Center for Health Statistics National Vital Statistics System. Births: final data for 2005. Natl Vital Stat Rep. 2007;56(6):1-103.

(8.) Su L, Land KJ. Information systems: expanding the reach of biovigilance. AABB News. May/June 2007.

(9.) Prigent A. Monitoring renal function and limitations of renal function tests. Semin Nucl Med. 2008;38(1):32-46.

(10.) Fontsere N, Bonal J, Navarro M, et al. A comparison of prediction equations for estimating glomerular filtration rate in adult patients with chronic kidney disease stages 4-5: effect of nutritional status and age. Nephron Clin Pract. 2006; 104(4):160c-168c.

(11.) Bachner P. Patient outcomes and pathology practice--an introduction to the College of American Pathologists Conference XXXIV on Molecular Pathology: role in improving patient outcome. Arch Pathol Lab Med. 1999;123(11):996-999.

(12.) AABB. U.S. Biovigilance Network. Programs_d_Services/Data_Center/US_Biovigilance_Network. Accessed August 17, 2008.

(13.) The Joint Commission. Blood Management Performance Measures Project. Blood+Management+-+Utilization.htm. Accessed August 17, 2008.

(14.) Edwards GA. Expert systems for clinical pathology reporting. Clin Biochem Rev. 2008;29(suppl 1):105S-109S.

(15.) Hirose TG, Mays DA. The safety of RhIG in the prevention of haemolytic disease of the newborn. J Obstet Gynaecol. 2007;27(6):545-557.

(16.) Dzik WS, Beckman N, Selleng K, et al. Errors in patient specimen collection: application of statistical process control. Transfusion. 48(10):2143-2151.

(17.) U.S. Food and Drug Administration. General Principles of Software Validation: Final Guidance for Industry and FDA Staff. Rockville, MD: Centers for Devices and Radiological Health and Center for Biologics Evaluation and Research. January 2002.

(18.) Association for the Advancement of Technical Instrumentation. Technical Information Report: Validation of Software for Regulated Processes; April 2008. AAMI TIR36:2007.

(19.) Vogel DA. Validating software for manufacturing processes. Med Dev Diag Indus. 2006;28:122-135.

(20.) Hernandez JS. Cost-effectiveness of laboratory testing. Arch Pathol Lab Med. 2003;127:440-445.

(21.) Committee on Quality of Health Care in America, Institute of Medicine. To Err Is Human. Washington, DC: National Academies Press; 1999.

(22.) Morris JA Jr, Carrillo Y, Jenkins JM, et al. Surgical adverse events, risk management, and malpractice outcome: morbidity and mortality review is not enough [discussion in: Ann Surg. 2003;237(6):851-852]. Ann Surg. 2003;237(6):844-851.

From Bonfils Blood Center, Denver, Colorado.

Kevin J. Land, MD; Monica LaSarre, MT(ASCP), SBB; Marty Straley, BS, MS

The authors have no relevant financial interest in the products or companies described in this article.

Reprints: Kevin J. Land, MD, Bonfils Blood Center, 717 Yosemite St, Denver, CO 80230-6918 (e-mail:
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Author:Land, Kevin J.; LaSarre, Monica; Straley, Marty
Publication:Archives of Pathology & Laboratory Medicine
Article Type:Editorial
Geographic Code:1USA
Date:Mar 1, 2009
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