PATIENT SAFETY DIAGNOSTIC ERROR SURGICAL PATHOLOGY

Transcription

1 PATIENT SAFETY & DIAGNOSTIC ERROR in SURGICAL PATHOLOGY Richard J. Zarbo, M.D., D.M.D. Rita D Angelo, M.S., ASQE, SSBB Pathology and Laboratory Medicine Henry Ford Health System Detroit, Michigan

2 Zarbo-D Angelo page 2 Objectives 1. Identify improvement opportunities that improve patient safety. 2. Appreciate the magnitude and importance of preanalytic patient identification errors. 3. Understand a framework for classifying surgical pathology errors that translates into standardized, documented and issued amended reports. 4. Identify mechanisms for timely communication and documentation of significant or unexpected surgical pathology diagnoses. 5. Appreciate the next Cultural Revolution in quality improvement Henry Ford Production System. Introduction The topic of patient safety became an important subject in medicine with the publication in 1999 of the United States Institute of Medicine s report on medical error and its subsequent report on the general state of quality of health care in This focus on error reduction also extends to the laboratory where patient s safety can be summarized as doing the right thing, at the right time, for the right patient. The patient safety movement builds on, and is an evolution of previous quality movements, such as quality control, quality assurance and quality improvement, but necessarily focuses on that portion of the Hippocratic oath calling us above all, to do no unnecessary harm. Unfortunately, humans err often and therefore, error is a common fact of life. Approaches to patient safety take this fact to heart, focusing not on the human, but instead on the redesign of systems to minimize the consequences of inevitable human error. The most common causes of error from root cause analyses are those of mis-communication, poorly defined connections between individuals, inappropriate pathways of action, low cultural expectations, and poor teamwork. Clearly, the quest for improved quality and patient safety is never ending, given the current design of systems and human nature. The College of American Pathologists elaborated on its laboratory patient safety goals in late Those four goals which each laboratory must document that it has addressed by evaluation and monitoring of the processes involved include the following: 1. Patient and sample identification at specimen collection, analysis and resulting. 2. Timely identification, communication and correction of errors. 3. Verification and communication of life threatening, life altering information. 4. Coordination of the patient safety role in health care organizations. Identification Errors Defects in the pre-analytic phase of testing, namely that of specimen labeling and lab tag requisition accuracy, are fairly common. In the 1993 Q-Probes study of over one million case accessions from 417 laboratories, the overall specimen defect (deficiency) rate was 6%. The most common defect was that of incorrect or missing information or no clinical history provided with the specimen. Fewer cases had defects in handling or were lost in transportation. However, notably 9.6% of specimens had defects in patient identification and, in fact, 1.8% had no label on the specimen container at all. So how does the magnitude of these defects translate into the Six Sigma world of defects? Placed on that scale where a defect rate of Six Sigma translates to 3.4 defects per million, the aggregate percentage of defective surgical pathology cases would equate to a 2-3 Sigma performance or roughly 60,000 defects per million. To put this in context, the safety of the American Space Shuttle Program, recognizably flawed, would be 20,000 defects per million, or roughly 2% error (two shuttles lost per 103 flights). So, more importantly, what proportion of defects in surgical pathology are related to mis-identification or lack of identification of the patient? In our own examination of 430 amended surgical pathology reports from three years of practice, misidentification was the second most common defect that resulted in an amended report. Interestingly, non-diagnostic report defects were far and away the most common deficiency and frank misinterpretation defects ran third, close in frequency to the mis-identification rate. But is this method of surveillance from amended reports a true reflection of identification error? If we make use of our experience in the blood bank where we have previous blood types on record, we can extrapolate a blood collection mis-identification rate of roughly 1,000 per million. Similarly, using morphologic recognition of tissues that do not match the anatomic site or are from patients known not to have been biopsied, the surgical pathology defect rate is about 240 per million mis-identified specimens processed per year. Clearly, there is a very wide range of mis-identification taking place under our watch, the true magnitude of which can only be crudely estimated at this point in time.

3 Zarbo-D Angelo page 3 These identification errors may arise anywhere in the test cycle. Although we often impugn the preanalytic component of testing, that is a specimen with defective identification submitted to the laboratory, in fact, a significant number of misidentifications take place within the laboratory: in accessioning, tissue and slide processing, at the pathologist s microscope and at transcription. Further, additional opportunities for mis-identification take place in the post-analytic phase of paper or computer reporting. All these aspects of process involve humans, multiple handoffs, and inevitable slip errors whereby we often form the appropriate goal but go about the action in an inappropriate manner. These mis-identification errors may be further compounded by quick and superficial fixes to relabel specimens in the absence of assured identification. To minimize the chance for this type medical disaster, regulatory agencies currently require two forms of patient identification on each specimen container and requisition. It is also suggested that the addition of a barcode be employed and that handwritten or manual specimen label identification and/or reentry of identifying numbers at accession be avoided. For those of us who design the systems in which we work, simplification of lab processes and built-in redundant checks can be extremely helpful in avoiding mis-identification errors throughout the surgical pathology process. More recent molecular techniques may also allow us to verify tissue identity at the DNA level, rather than making identification reassignments based on clinical assumptions. A quality monitor of defined surveillance for and documentation of identification errors is a very useful continuous monitor. It can capture not only errors that have escaped the laboratory but also those common near-misses that have been caught and corrected in process. This is useful information that may be used to focus education of personnel on proper labeling and identification, both within and outside the boundaries of the laboratory. Efforts to establish continuous education, directed communication and standardized protocols in processes are all helpful in reducing identification error. Adoption and implementation of a specimen labeling and rejection policy with defined opportunities for specimen rehabilitation and/or relabeling are also appropriate. In our own institution, implementation of such a specimen labeling and acceptability policy dramatically reduced the number of specimens with identification defects by over 98% in a few short months. Surgical Pathology Errors and Amended Reports Through our ongoing Agency for Healthcare Research and Quality grant funded investigation of anatomic pathology error, we have developed a taxonomy of report defects from the analysis of amended reports. That taxonomy includes four categories of defective interpretation, defective identification, defective specimen and defective report. Using this four-part taxonomy we have retrospectively reviewed all amended reports generated for three years, spanning nearly 150,000 surgical pathology cases. We find that the amended report frequency ranges from amended reports per 1,000 issued. This has been a fairly consistent rate in our practice, over a period with no major process changes. Using this taxonomy, report defects are the most common, 28-44%. These include reports with erroneous or missing nondiagnostic information, dictation or typing error, report delivery error or computer format, transmission or upload error. The second most common defect is that of specimen or patient misidentification which ranges from 27-38% of the amended reports. These identification defects can be further classified as those at the patient level, tissue, laterality (right vs. left) or anatomic location specification. The third most common error is that of mis-interpretation, ranging from 23-28% of amended reports issued. Interpretation errors can be classified as microscopic false-negatives (undercall), microscopic false-positive (overcall), or microscopic misclassification. The undercalls and overcalls may be further classified as those dealing with primary diagnoses (positive-negative or benign-malignant) or secondary diagnostic characteristics such as tumor grade, stage, and margin. And lastly, defects related to the specimen itself or its handling are the fourth most common root cause of amended reports, counting for 4-10%. Defective specimens include those that are lost, of inadequate volume, size, gross description, erroneous measurement or extraneous tissue. This category also includes inadequate representativeness, sampling at the tissue block or slide level and those cases in which pertinent ancillary diagnostic studies are not initially done. From this analysis of these amended surgical pathology reports over a three year period, we conclude that the overall amended report defect rate is 2.9 per 1,000 surgical pathology cases. Roughly 5%, or 1 in 20 reports, had multiple errors using the taxonomy presented % of the amended reports were generated from tumor boards and the remainder from quality assurance review activities and clinician-initiated reviews. The high value of tumor board review is reflected in the significant

4 Zarbo-D Angelo page 4 percentage of the interpretative errors (52-73%) that this process detected. However, the question of the timing of the discovery of these interpretative defects, in relation to subsequent patient diagnostic and therapeutic efforts awaits a true outcome analysis. Clearly, errors commonly occur and they provide rich material for pathologists to track, trend, present for educational purposes and stimulate thinking about process and system redesign. The CAP inspection checklists call for documented systems to ensure that all revised reports for previously reported incorrect (erroneous) patient results are identified as revised, corrected or amended on all forms of patient reports and that when revised results are reported that the revised and original data are clearly identified as such and that the original data are accessible to the user for comparison. The current state of amended reports is that there is no standardization of terminology such that terms revised, corrected, amended, supplemental, addendum and additional may be appended to these reports with mixed meaning. Further, there are system limitations pertaining to whether a laboratory issues paper or electronic reports or both. Consideration should be given to whether these paper reports need to be withdrawn everywhere they have been issued or retrieved, then left in place, stamped disregard issued in error. Or, in the case of electronic reports, one should know whether the electronic report remains within the computer system or is overlaid with one that will require specific wording retaining the original erroneous diagnosis in some form. Other considerations are specific to laboratory information systems which may dictate what that second issued report is called and how the original information is presented, if at all. In addition, it is useful to document how amended reports are subsequently presented in the hospital information system and the sequence in which those second reports are presented to the caregiver. We have found in our own environment that creation of an amendment dictionary menu aligned with the error taxonomy previously presented has been helpful in standardizing the approach to amended reports, the documentation of the cause of the error and the subsequent root cause analysis. We classify our amended reports as interpretation (diagnosis), identification (mis-identification), specimen, report and information technology (computer) reasons for amendment. Further, for the issuance of amended reports for diagnosis or mis-identification, there is a requirement that the licensed caregiver notified be documented within the body of the amended report, as well as the date and time. Critical Values in Anatomic Pathology The CAP patient safety goal, calling for verification and communication of life threatening or life altering information such as malignancy, HIV, serious infections, and critical values is one that can met in a variety of ways. Specific checklist language calls for laboratories to have procedures for immediate notification of a physician or other clinical personnel responsible for patient care when results of certain tests falls in established alert or critical ranges. Further, there is a call for documentation of notification of the appropriate clinical individual of all critical values and for the laboratory to have a verifying read-back of critical values that are communicated verbally or by phone. These regulations are those to which the clinical laboratories that report critical values adhere in the United States. The specific regulation addressing anatomic pathology results calls for a policy regarding timely communication and documentation thereof of significant or unexpected surgical pathology findings. Further, the regulation specifies that diagnoses defined as significant or unexpected, if any, should be determined by the pathology department in cooperation with the local clinical medical staff, affording a certain degree of local autonomy. It also states that consideration should be given to assuring, with reasonable effort, prompt communication of such results by telephone, pager or other system and that there should be documentation of date and time of such special notification which may be included in the pathology report or laboratory files. We believe that the last requirement should include the documentation of the person notified for all cases in which the diagnosis or identification of any part of the case has been changed. In dealing with these regulatory requirements, we have clarified in our AP policy that the vast majority of anatomic pathology significant values are, in fact, not critical values and do not require a read-back as performed in the clinical pathology laboratories. We have designated these priority diagnoses as action-alert diagnoses in anatomic pathology. This signifies diagnoses that are elevated to an enhanced notification and documentation status. In fact, in our last AP customer satisfaction survey, this was the number one physician request for more effective communication of abnormal results. We have taken the approach that these notifications may be made either by phone call with documentation of who, what and when or by use of our electronic medical record in-box notification whereby results so posted

5 Zarbo-D Angelo page 5 require physician closure and subsequent documentation or after a certain period of time, transmission of that notification to a back-up caregiver. Currently, our list of action-alert diagnoses includes: 1. Giant cell arteritis in temporal artery biopsy (positive value) 2. Significant microorganisms e.g. CMV, significant fungi including angioinvasive fungi, and organisms in physiologically sterile body sites. 3. Gestational endometrium without placenta or fetal tissue. 4. Completely unexpected or first time diagnosis of malignancy. 5. Evidence of perforated uterus or other viscus. 6. Cytopathology non-gynecological and fine needle aspiration biopsies that are suspicious or positive for malignancy. 7. Cytopathology Pap smear diagnoses of HSIL, suspicious or positive result. 8. Amended reports issued for patient misidentification or changed diagnosis. Henry Ford Production System For a long time quality assurance and improvement activities in anatomic pathology have focused on the identification of benchmarks of performance that describe current practice and attempted to satisfy accreditation requirements for continuous monitoring. This has often meant striving to perform at the median or mean benchmark performance level. These peer derived goals set the bar too low. For over fifteen years this focus on quality has resulted in no significant performance improvements. For instance, in 1993 the 525 laboratories participating in a Q-Probes study completed 79% of routine biopsies in one day. That turnaround time has not improved significantly since. The new paradigm in quality improvement is that of applying lean production principles to the laboratory. In its ultimate form, applications like the Toyota Production System will change the underlying culture of the laboratory to that of a continuously learning workforce, continually making scientifically based rapid process improvements while striving toward the ideal performance level. Whereas in the old paradigm decision-making about improvements was top-down from management, in the new lean paradigm for improvement, ideas and decision-making are derived from the bench level up. Whereas in the old paradigm the laboratory service or product was offered when we got to it, in the new paradigm the product is produced when and how the customer wants it. In the old paradigm we would gear up for increased production with more staff but in the new model we often find that less staff is needed to do more. Our laboratory-wide effort to implement the Toyota Production Principles to perfecting processes and patient safety is known as the Henry Ford Production System. Our goal is to become best in class for defect reduction and elimination of waste, thereby globally increasing quality. It is our goal to change our culture to that of one that continually improves quality, with our employees incrementally moving to the ideal condition, continuously in a self-directed fashion. Here we share our early successes in implementing the production redesign principles, goals and quality organizational structure of the HFPS, as well as the lessons learned from people, leadership and operational challenges. In the Henry Ford Production System we have built on the original Henry Ford approach to mass production melded with automation and elimination of waste and time, to include the Toyota Production Principles that go beyond mass production. The latter refinements include continuous production flow based on demand, pull production, autonomation and an empowered workforce incrementally innovating to move toward the ideal condition, continuously. There are numerous improvement opportunities that now arise from these adopted production and redesign principles that include standardized tasks and workstations, continuous process flow based on pull rather than push, workload leveling, visual controls and change decision making based on careful, scientific study and data proof of effectiveness. As an example, from our previous experience in over 16 years of studying opportunities in improvement of quality in defining benchmarks of performance and errors in anatomic pathology processes through the College s Q-Probes and Q- Tracks Programs, we had come to appreciate the majority of errors occurred in the pre-analytic and post-analytic phase of testing, rather than within the laboratory (the analytic aspect of testing). This impression we now recognize, was an artifact of the tools and measures employed in those multiinstitutional studies. In the Henry Ford Production System, we have attempted to define the true magnitude of defects that arise within the surgical pathology process from pre-analytic through post-analytic phases. We began by polling all AP professional, technical and secretarial staff, asking them to list the top ten defects they commonly encounter that required them to accept less than standard work, to stop work, to

6 Zarbo-D Angelo page 6 fix an error or to return work to the sender. From this information we created 100 indicators of potential defects in surgical pathology. Nine data collection posters were created and posted in each work unit, such that 57 personnel in anatomic pathology could identify defective cases in real time in a public display. Using this methodology, we found that the majority of defects arise within the analytic phase of testing rather than the pre- and post-analytic phases as previously thought. The top four analytic defects related to histology slides, defects at accessioning, defects in the gross examination of tissues and in recuts. Over a span of two weeks, comprising 1690 surgical pathology cases, we encountered a collective defect rate of nearly 28%. Clearly, this magnitude of error that takes place within our complex processes on a daily basis provides us with great opportunities for improvement. References 1. College of American Pathologists Commission on Laboratory Accreditation: Laboratory General and Anatomic Pathology Checklists, College of American Pathologists: Northfield, IL, Kohn LT, Corrigan JM, Donaldson MS, eds. For the Committee on Quality Health Care in American. To Err is Human: Building a Safer Health System. Washington, DC: Institute of Medicine National Academy Press; Nov. 1, Liker JK: The Toyota Way. 14 Management Principles from the World s Greatest Manufacturer. New York: McGraw Hill, Meier FA, Varney R, Bansal M, Zarbo AJ, Schultz D, Raab S, Zarbo RJ: Validation of an error taxonomy system for anatomic pathology. Abstract Mod Pathol 18:1506, Nakhleh RE, Zarbo RJ: Amended reports in surgical pathology and implications for diagnostic error detection and avoidance: a College of American Pathologists Q-Probes study of 1,667,547 accessioned cases in 359 laboratories. Arch Pathol Lab Med, 122: , Nakhleh RE, Fitzgibbons PL (eds): Quality Management in Anatomic Pathology. Promoting Patient Safety through Systems Improvement and Error Reduction. College of American Pathologists: Northfield, IL, Ohno T: Toyota Production System. Beyond Large-Scale Production. Portland, OR: Productivity Press, Raab SS, Nakhleh RE, Ruby SG: Patient safety in anatomic pathology. Measuring discrepancy frequencies and causes. Arch Pathol Lab Med 2005;129: Schifman RB, Howanitz PF, Zarbo RJ: Q- Probes: A College of American Pathologists Benchmarking Program for Quality Management in Pathology and Laboratory Medicine. In: Weinstein RS (ed): Advances in Pathology and Laboratory Medicine. Vol. 9. Mosby-Yearbook, Inc., Chicago, 1996, pp Zarbo RJ, Gephardt GN, Howanitz PJ: Intralaboratory Timeliness of Surgical Pathology Reports: Results of Two College of American Pathologists Q-Probes Studies of Biopsies and Complex Specimens. Arch Pathol Lab Med 1996;120: Zarbo RJ, Rickert RR: Quality Control, Quality Assurance and Quality Improvement in Anatomic Pathology. In Silverberg S, DeLellis R, Frable J (eds.): Principles and Practice of Surgical Pathology and Cytopathology. 3 rd Edition. New York: Churchill Livingstone, Zarbo RJ: Monitoring Anatomic Pathlogy Practice Through Quality Assurance Measures. In: Raab SS (ed.): Pathology Outcomes, Clinics in Laboratory Medicine. Philadelphia: W.B. Saunders, CO., December 1999, pp Zarbo RJ, Jones, BA, Friedberg RC, et al: Q- Tracks: A College of American Pathologists Program of Continuous Monitoring and Longitudinal Performance Tracking. Arch Pathol Lab Med 2002;126: Zarbo RJ, Meier FA, Raab SS: Error reduction in anatomic pathology. Arch Pathol Lab Med 2005;129: