Pathology Consultation On Reporting of Critical Values [PDF]

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Pathology Consultation / Special Article



Pathology Consultation on Reporting of Critical Values Jonathan R. Genzen, MD, PhD,1 and Christopher A. Tormey, MD,2 for the Education Committee of the Academy of Clinical Laboratory Physicians and Scientists Key Words: Pathology consultation; Critical values; Critical results; Panic values; Laboratory results; Results reporting DOI: 10.1309/AJCP9IZT7BMBCJRS



The ASCP is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The ASCP designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit ™ per article. This activity qualifies as an American Board of Pathology Maintenance of Certification Part II Self-Assessment Module. The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose. Questions appear on p 643. Exam is located at www.ascp.org/ajcpcme.



Abstract



Case Scenario



Among the most important functions of a pathology or laboratory medicine service is the clear, accurate, and rapid communication of critical test results (critical values) to patient care providers. Pathologists and laboratory professionals are often confronted with many obstacles in the reporting of such critical values, including establishing clinically relevant criteria for critical values, resolving difficulties in locating an ordering provider when a critical value is obtained, and ensuring that the provider understands the severity and implications of a critical result when he or she has questions. This article presents a hypothetical (yet fairly common) clinical case scenario regarding critical values and then provides an up-to-date discussion and review of the literature on the reporting of critical results.



A patient with atrial fibrillation who is receiving warfarin has an afternoon cardiology appointment for routine care and anticoagulant monitoring. A basic metabolic profile and prothrombin time are ordered. The specimen is transported to the laboratory by courier, and laboratory testing is completed at 7:30 PM. All values are within normal limits except for an elevated potassium level (K+) of 6.9 mEq/L (6.9 mmol/L; reference range, 3.2-5.2 mEq/L [3.2-5.2 mmol/L]) and a prothrombin time of 64.7 seconds (reference range, 11.1-13.2 seconds), corresponding to an international normalized ratio of 7.4. These results qualify as critical values by your clinical laboratory policy, and the laboratory technologist attempts to contact the ordering clinician by telephone. Calls to the physician’s office are not forwarded to an answering service or covering clinician, but rather directed to an office answering machine. The ordering physician does not respond to pages or telephone calls made to the contact numbers listed in the hospital telephone directory or laboratory information system (LIS). The laboratory technologist contacts the on-call pathology resident and asks for assistance.



Questions 1. What are laboratory critical values? 2. What are the requirements for critical value reporting? 3. How should clinical laborattories establish critical value lists and determine appropriate thresholds? 4. Who should make and receive critical value notifications? 5. How might critical value reporting be improved? © American Society for Clinical Pathology



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Upon completion of this activity you will be able to: • define the terms “critical value” and “critical diagnosis.” • examine obstacles associated with reporting critical values and diagnoses in a laboratory setting. • discuss practical solutions for problems associated with critical value reporting.



Genzen and Tormey / Critical Values



6. What are the responsibilities of pathologists and laboratory directors in the critical value process?



Background



Regulations Critical value reporting is required by a variety of laws, regulations, and accreditation programs. In the United States, the Clinical Laboratory Improvement Amendments of 1988 (CLIA ’88) include requirements on critical value reporting. Current regulations specify that the laboratory manual must address critical values (when applicable to test procedures), along with protocols for reporting critical value results [see §493.1251 (b; 11 and 13); and §493.1291 (g)].6 The Joint Commission (TJC) National Patient Safety Goals also address critical value reporting. Specifically, Goal 2—improve the effectiveness of communication among caregivers—includes “report critical results of tests and diagnostic procedures in a timely basis.” This goal and its specific performance elements were updated in 2010 and are available online.4 Of note, the read-back requirement for results conveyed by telephone is being changed to a formal standard. Read-back is imperative 506 506



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Establishing a Critical Values List Although there are many regulations specifying that laboratories must define and communicate critical values, it may seem surprising that regulations do not state which laboratory tests require critical value limits and notification. Indeed, individual clinical laboratories face unique challenges that reflect institutional organization, clinical demand, patient population, instrumentation, and staffing. Such variations have hindered the development of universal standards for critical value reporting across laboratories. The idea of a universal critical value list is appealing to many laboratorians and clinicians. For example, many clinicians would likely consider a sodium (Na+) level of 168 mEq/L (168 mmol/L) a “critical” value regardless of which laboratory performs the test. Indeed, the practice of assigning the laboratory director responsibility for creating and refining the critical value list has led to similar overall inclusion of tests between laboratories without there being a universal mandate or requirement. As an example, virtually all laboratories include Na+ on their critical value list precisely because it is important for patient care. Furthermore, not communicating a critically elevated Na+ level could have medicolegal ramifications if an adverse clinical outcome occurred. Defining (and then mandating) a universal set of thresholds for tests, however, would be a daunting task given the scarcity of outcomes-based data on critical value thresholds. Inherent variability in assay-specific reference intervals between institutions is also a complicating factor. An individual laboratory director can account for this variability by defining critical ranges consistent with his or her own assays and instrumentation. How should a laboratory determine which tests to include on a critical value list? Moreover, how should the critical high and low thresholds be established? While ultimately, this determination is the responsibility of the laboratory director, it should be made in communication with the clinicians who use © American Society for Clinical Pathology



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Lundberg1 first outlined the fundamental components of critical value reporting in a Medical Laboratory Observer article, describing critical laboratory values as “values which reflect pathophysiological derangements at such variance with normal as to be life threatening if therapy is not instituted immediately.” They have more recently been described as “laboratory results that indicate a life-threatening situation for the patient. Because of their critical nature, urgent notification of a critical value to the appropriate healthcare professional is necessary.”2 Alternative terms for critical values include critical results, panic values, and alert values. The term panic values carries a suggestion of emotional stress and runs against the thoughtful and organized process of communicating important information clearly. Its use is therefore discouraged. Laboratories are required by numerous regulatory agencies to develop and put into practice critical value policies.3-6 Although the content of these policies varies according to institutional needs, the core components are often quite similar. This article begins by describing the current regulatory requirements for critical value reporting. This information will be followed by a detailed analysis of the fundamental components of critical value notification. Aspects of critical value reporting that have been evaluated in the literature are emphasized, as are current technological advances that may change the way in which critical value reporting takes place.



because significant error rates have been detected in the process of telephone result communications.7,8 Additional state, provincial, and local regulations regarding critical value reporting may also exist and can be relevant to an individual laboratory’s performance requirements. Critical value reporting is addressed by the College of American Pathologists (CAP) Laboratory Accreditation Program as part of several checklist components.3 These items delineate the specific requirements for critical value procedures, including documentation of reporting and read-back of verbally communicated results. Finally, the International Organization for Standardization also includes critical value reporting in its clinical laboratory standard ISO 15189:2007.5



Pathology Consultation / Special Article



Critical Value Notification Procedures The initial step in the critical value communication process involves identification of an abnormal result by someone in the laboratory.9 For automated assays, the instrument, middleware,



or LIS will notify the laboratory staff (usually the performing technologist) of the critical value. Laboratory policies must clearly indicate whether the assay should be verified and/or repeated before reporting and, if so, within what time frame. Repeat testing is not feasible in many circumstances (eg, blood culture results), and ongoing improvements in laboratory assays may decrease the clinical usefulness of routine repeat testing before reporting. This is a topic of continued clinical interest and debate. The National Patient Safety Goals state that laboratory procedures must indicate “by whom and to whom” critical results are reported, as well as “the acceptable length of time between the availability and reporting of critical results.”4 Documentation is required. The CAP checklist (component GEN.41330) specifies what information must be documented during critical value notifications, including “date, time, responsible laboratory individual, [and] person notified.”3 Laboratory personnel who perform the actual tests are currently responsible for making the vast majority of critical value notifications. A 2008 survey of 121 institutions found that approximately 90% of calls are made by medical technologists/technicians, 1% are made by client services or call center staff, and 9% are made by a combination of the two.26 A 2002 survey of 623 institutions showed similar results, with some differences between inpatient and outpatient notification.13 That study recommended that critical value notifications should be made by one of the “team members” involved in performing the procedure.13 A separate 2008 survey of laboratory professionals and pathologists (at >350 hospitals) revealed that nearly 18% of respondents were using a call center for critical value notifications.27 The workflow benefits of centralized call centers (and having a laboratory technologist or someone with laboratory expertise involved in the call center mechanism) are well described in the aforementioned survey and a separate 2008 CAP Today feature article.27,28 Laboratories face an ever-increasing dilemma in critical value notification—the overall volume of laboratory testing is increasing, but a continued shortage in the number of laboratory professionals means that fewer people are expected to do more. Shifting the task of critical value notification away from laboratory technologists may be inevitable at many institutions. Indeed, several hospitals have implemented the use of automated notification systems for critical value reporting. At one institution, critical values transmitted from the LIS to a hospital clinical information system trigger the generation of text messages directed to the responsible clinician’s mobile phone and computer.15 If the clinician does not confirm receipt in the clinical information system within 60 minutes, results are communicated by telephone. This approach improved the speed of communication and allowed for full electronic documentation of critical value reporting.



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laboratory services, as well as with a medical review board of the institution, if applicable.3,9 This task may include meeting with relevant physicians, medical and surgical section chiefs, hospital administrators, and/or nurse managers to discuss critical value policies and to determine if there are any tests that should be included (or omitted) and whether any thresholds should be adjusted according to clinical needs. Not every laboratory test should have critical values associated with it. Critical value lists are, by nature, limited to not hinder the clinical effectiveness of notification.1 Critical lists that are too inclusive (or that have critical value thresholds that require excessive notification) place an unnecessary burden on laboratory staff. Such lists annoy clinicians, foster a negative attitude toward important laboratory services, and, most important, provide uncertain additional benefit to patient care. At the other extreme, lists that are too exclusive (or with thresholds that are too high or low) might not prevent adverse clinical outcomes, as a delay in the recognition of lifethreatening laboratory results by clinicians can be disastrous. A balance must be achieved. The best place to start when establishing or modifying critical value lists is by comparison with previously published lists, practice parameters, and consensus documents because these sources have been refined with the benefit of time, institutional comparison, and clinical performance.2,9-18 Several published studies from CAP (Q-Probes and Q-Tracks) have compared critical value reporting across hundreds of institutions and are a valuable resource for critical value policy assessment. The 1997 American Society for Clinical Pathology “Critical Values Practice Parameter” (published in the Journal) is another outstanding resource.9 ❚Table 1❚ and ❚Table 2❚2,3,9,13,14,16-21 present lists of common tests that frequently have critical values defined. Although most published critical value lists do not include blood bank testing, we have included a number of transfusion medicine–related scenarios that may benefit from rapid communication and discussion with a responsible clinician. It should be noted that most published reports focus on critical value notifications in general laboratory testing, although several studies of critical diagnoses in surgical pathology and cytology have recently been published and will be discussed later in this article. Finally, many institutions place their laboratory policies (including critical value lists) online, facilitating comparison of lists between peer laboratories.22-25



Genzen and Tormey / Critical Values



❚Table 1❚ Examples of Possible Critical Laboratory Values for Chemistry, Hematology/Coagulation, and Pediatric-Specific Ranges* High Threshold



—



100 (35.7)



6.5 (1.6) 3.2 (0.8) 10 (10) 75 (75) — 45 (2.5) 40 (2.2) — 1.0 (0.4) 250 (250) 1.0 (0.3) 40 (5.3) 20 (2.7) 7.2 2.8 (2.8) 120 (120) — —



13 (3.3) 6.2 (1.6) 40 (40) 125 (125) 6.0 (530.4) 450 (25.0) 200 (11.1) 30.6 (3.4) 4.9 (2.0) 325 (325) 9.0 (2.9) — 70 (9.3) 7.6 6.2 (6.2) 160 (160) See comment† 13 (773)



— — 90 (2.6) 7 (70) 20 (0.2) 40 (40) 2 (2) — —



30‡ 80 800 (23.5) 20 (200) 60 (0.6) 1,000 (1,000) 40 (40) First observation First observation



—



First observation



— —



First observation 5



— — — — 30 (1.7) 40 (5.3) 20 (2.7) 2.8 (2.8) 121 (121) 10 (100) 33 (0.33) 50 (50)



154 (110.0) 15 (256.5) 55 (19.6) 3.8 (335.9) 325 (18.0) 100 (13.3) 63 (8.4) 7.8 (7.8) 156 (156) 22 (220) 71 (0.71) 900 (900)



30 (1.7) —



200 (11.1) 190 (1.9)



— — —



30 20 10



CSF, cerebrospinal fluid. * Information in this table is meant as a starting point for the evaluation of a laboratory’s critical value list and not as a strict guideline applicable to all clinical scenarios. The table incorporates critical value data from the literature, particularly the outstanding reports from Kost,16-18,20,21 the College of American Pathologists Q-Probes studies,13,14 the ASCP Practice Parameter,9 a pediatric study by Gong and Adeli,12 and critical values included in the Tietz Textbook of Clinical Chemistry and Molecular Diagnostics.2 Système International (SI) conversion factors can be found in textbooks.2 In many cases, SI values have been rounded to 1 decimal point for the purposes of clarity. Because the table integrates information from multiple studies, tests (and ranges) may vary from individual sources and may not be representative of the original authors’ opinions. The table is also not inclusive of all tests that may be considered critical. For example, it does not include toxicology and therapeutic drug monitoring owing to the diversity of tests performed between individual institutions. † First result observed above an assay or laboratory-defined cutoff for myocardial infarction. A discussion of one laboratory’s experience in establishing a troponin critical value cutoff (in collaboration with the emergency department) can be found in a 2008 CAP Today feature article.19 ‡ An international normalized ratio equivalent (eg, >5) may also be used.



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Chemistry Blood urea nitrogen, mg/dL (mmol/L) Calcium, mg/dL (mmol/L) Total Ionized Carbon dioxide, total, mEq/L (mmol/L) Chloride, mEq/L (mmol/L) Creatinine, mg/dL (μmol/L) Glucose, mg/dL (mmol/L) Glucose, CSF, mg/dL (mmol/L) Lactate, mg/dL (mmol/L) Magnesium, mg/dL (mmol/L) Osmolality, mOsm/kg (mmol/kg) Phosphate, mg/dL (mmol/L) PO2, mm Hg (kPa) PCO2, mm Hg (kPa) pH Potassium, mEq/L (mmol/L) Sodium, mEq/L (mmol/L) Troponin I or T Uric acid, mg/dL (μmol/L) Hematology/coagulation Prothrombin time, s Partial thromboplastin time, s Fibrinogen, mg/dL (μmol/L) Hemoglobin, g/dL (g/L) Hematocrit, % (proportion of 1) Platelet count, × 103/μL (× 109/L) WBC count, × 103/μL (× 109/L) Blasts Organisms/parasites detected on smear review (CSF, blood, or sterile body fluid) Smear review suggestive of microangiopathic hemolytic anemia (schistocytes and low platelet count) Urinalysis (pathologic crystals) WBC count, CSF (cells/μL) Pediatric-specific ranges Ammonia, μg/dL (μmol/L) Bilirubin, neonatal, mg/dL (μmol/L) Blood urea nitrogen, mg/dL (mmol/L) Creatinine, mg/dL (μmol/L) Glucose, neonatal, mg/dL (mmol/L) PO2, neonatal, mm Hg (kPa) PCO2, neonatal, mm Hg (kPa) Potassium, neonatal, mEq/L (mmol/L) Sodium, pediatric, mEq/L (mmol/L) Hemoglobin, neonatal, g/dL (g/L) Hematocrit, neonatal, % (proportion of 1) Platelet count, × 103/μL (× 109/L) CSF Glucose, mg/dL (mmol/L) Protein, mg/dL (g/L) WBC count, cells/μL 0-1 y 1-4 y 5-17 y



Low Threshold



Pathology Consultation / Special Article



❚Table 2❚ Examples of Possible Critical Laboratory Values for Microbiology and Transfusion Medicine* Microbiology Positive Gram, acid-fast bacillus, or mycology stains of smears (CSF, blood, or sterile body fluid) Positive blood cultures Positive CSF cultures Positive sterile body fluid cultures Positive stool culture for select organisms Positive bacterial antigen tests Transfusion medicine† Gross, visible hemolysis in a post–transfusion reaction specimen Positive direct antiglobulin test (IgG and/or C3) in a post–transfusion reaction specimen Evidence of crossmatch incompatibility with a post–transfusion reaction specimen Discrepancy in identifiers noted on a blood product label, tag, or container during transfusion reaction evaluation Positive blood cultures from a unit implicated in a transfusion reaction Discovery of a new alloantibody in a patient undergoing surgery CSF, cerebrospinal fluid. * Information in this table is meant as a starting point for the evaluation of a laboratory’s critical value list and not as a strict guideline applicable to all clinical scenarios. † We have included possible transfusion medicine scenarios that would benefit from prompt communication with a responsible clinician, although most published critical value lists do not specifically include blood bank testing.



clinical personnel responsible for patient care)” and the “appropriate clinical individual.”3 CLIA refers to “the individual or entity requesting the test and, if applicable, the individual responsible for using the test results” [§493.1291 (g)].6 A 2007 survey of 163 clinical laboratories asked the question “Who can receive critical values?” for the inpatient and outpatient settings.14 As expected, answers from virtually all facilities included any licensed caregiver, ordering physician, on-call physician, or resident.14 Many laboratories, however, also permitted administrative personnel (ward clerks or receptionists) to accept critical values for outpatients (48%) and inpatients (27%). A separate 2008 study showed that almost 18% of institutions authorized release to other staff (eg, ward clerks and/or unit secretaries).26 In that study, the calls made to “other providers” occurred slightly more quickly than those made to licensed caregivers. Any timesaving was lost, however, when factoring in the subsequent time it took this other provider to then contact a licensed caregiver. The “authorized agent” approach to critical value notification (calling someone whom a licensed caregiver specifies can receive critical value notifications but is not necessarily capable or authorized to act on them independently) should be discouraged. Many facilities allow for reporting of critical values directly to licensed nurses, who are then responsible for conveying these results to ordering and/or covering physicians. According to most regulatory agencies, this would also be an acceptable practice as long as there is documentation that the critical value was then conveyed by the nurse to the ordering physician and/or licensed caregiver. As an alternative, some hospital networks have adopted a policy of reporting all critical values generated from the



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At another institution, an automated paging system was developed for critical value notification.11 In that program, critical values transmitted from the LIS generate a page containing the patient name, medical record number, collection time, critical result, and reference range. The clinician must confirm receipt of the critical value by dialing a phone number listed in the message. If the clinician does not respond within 10 minutes (or rejects the notification), the call is escalated to a trained group of operators who proceed with telephone notification. Implementation of that system increased documentation of critical value receipt by physicians and decreased the median time for notification. Several other studies have also evaluated the role of automated paging systems in critical value reporting.29,30 It should be emphasized that automated solutions should allow for an escalation policy (see the next section) to ensure communication of critical results when clinicians do not acknowledge receipt.10 Laboratory contact information should also be available so that clinicians with additional questions can ask a laboratory professional or medical director as appropriate. Patient privacy requirements should also be considered with automated solutions because data conceivably might be transmitted and stored on nonencrypted devices. Finally, device compatibility with alphanumeric characters (particularly units) and character limits should also be evaluated because an inaccurate or incomplete notification could lead to medical error and adverse clinical outcome. To whom should critical values be reported? The rationale stated in the National Patient Safety Goals states that results are to be conveyed to the “responsible licensed caregiver.”4 The CAP checklists describe notification to a “physician (or other



Genzen and Tormey / Critical Values



outpatient setting during “off” hours to a hospital emergency department (ED) or triage center. For example, the standard operating procedure at many Veterans Administration hospitals is to report critical results to an ED attending physician, who can then decide whether to act on these results. This approach works well for Veterans Administration hospitals, particularly because of the extensive electronic medical record (EMR) available to all clinicians. Such a call reporting system may be of limited benefit, however, at institutions with less robust EMRs. Results would still need to be conveyed to the responsible clinician for long-term management.



about a patient’s medical history and the potential ramifications of the critical value. We ultimately advocate for active involvement of a pathology resident, an attending pathologist, and/or a medical director in difficult-to-convey critical value calls. It has been our experience that this involvement usually opens avenues (eg, investigations via the EMR) that are not readily available to bench technologists. Such interventions can ultimately result in more rapid communication to a clinician familiar with the patient involved.



Repeat Critical Values Escalation Policies



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What should a laboratory do when a technologist is not able to reach a responsible clinician with the critical value? In these circumstances, abandoning the call entirely is almost never an acceptable solution. An escalation policy or a failsafe mechanism can be beneficial in such circumstances. An escalation policy would direct the laboratory technologist to contact a supervisor, pathology resident, and/or medical director to assist in critical value notification.28 This policy allows the technologist to refocus on the important task of laboratory testing, and it transfers the responsibility for notification to people who may have greater access to an inpatient or outpatient EMR and who can put the finding in a broader clinical context. In our experience, the pathology and laboratory medicine residents are usually able to contact a covering physician and convey these critical results. Verification of clinician notification should be subsequently conveyed back to the laboratory technologist (and entered into the LIS) to comply with TJC and CAP requirements. A fail-safe mechanism (or safety net) can also be used in cases in which notification continues to be unsuccessful.13,31 For example, if a “physician representing the laboratory” determines that immediate care of the patient may be required, the laboratory result and patient information might be conveyed to a physician in the ED to contact the patient directly.13 An approach to dealing with unreachable clinicians was recently proposed in a 2010 article.32 The report included algorithms for the inpatient and outpatient settings. After trying to contact the ordering provider, the algorithms include attempting to identify and contact the patient’s primary care provider. If still unsuccessful, a chief of service or chief of staff would ultimately be notified. This system has an added benefit of bringing the issue of critical value reporting to the attention of a hospital or departmental administrator who might not otherwise be aware of problems associated with the process. However, as with other systems in which the ordering provider is not the physician ultimately receiving the call, this process involves clinicians who may know very little



Another common problem in critical value reporting is how a laboratory should handle repeat critical values, or subsequent critical values for a given assay on the same patient (but subsequent specimen). Approximately 70% of surveyed laboratories have a policy on repeat critical values.27 For those that do not, one is strongly recommended because it will clarify laboratory technologist responsibility and establish consistency in performance. There are only 3 options: (1) Call only the first critical value. (2) Call each critical value. (3) Call critical values once per interval of time. As clinicians become quickly annoyed by repetitive calls for critical values, and as such calls may have diminishing value over time, some advocate using interval criteria (for example, calling once every 24 hours).13 Determining whether critical results meet interval criteria might add additional tasks to laboratory technologists, although LIS or middleware-based rules can be used to perform comparisons automatically. Others have suggested that interval calling is appropriate for only select analytes.9 Of note, one study demonstrated that lower rates of undocumented critical value results in the medical record were associated with policies that require calling all critical results.33 Such an approach in high-volume laboratories, however, can be exceedingly burdensome to technologists and clinical staff, and there are minimal data to argue the clinical benefit of one approach vs the other. Critical value lists and procedures should include not just critical ranges but also the frequency of when to call for each given test. A laboratory may determine that some tests should be called with each critical value, while others (such as a markedly elevated blood urine nitrogen level) may be called using an interval approach. The laboratory policy should also clarify how to handle critical value notification after a subsequent normal result during the same interval (eg, 8 AM, critical high; 9 AM, normal; then 10 AM, critical high). In our policies, if a normal test result occurs after a critical result, a subsequent critical result is considered new and would be called again. The laboratory’s policy should be clear for such scenarios.



Pathology Consultation / Special Article



Critical Value Audits



Opt-Out and Specific Lists Physician “opt-out” of critical value notifications (or “no call hours”) were prohibited by more than 80% of programs surveyed in one study.14 Opt-out is also strongly discouraged in the CAP checklist.3 The laboratory has a clear mandate to convey critical values, and permitting physician opt-out runs counter to the overall patient care objective of the notification process. Physician- and/or location-specific critical value lists are another issue of controversy. For example, clinicians at a dialysis clinic may be concerned about a different range of electrolyte results than clinicians at an orthopedics rehabilitation unit. Maintaining multiple, separate lists in the laboratory can be challenging (if not impossible) at most institutions and would be prone to technologist error in underreporting and overreporting of critical results. Physician- and/or locationspecific lists are not in widespread use. Many laboratories, however, include some populationspecific critical values. Critical value lists often include unique limits for neonates, but these values are easily incorporated onto a single laboratory-wide critical value list and would not be maintained separately. Tables including pediatrics critical value limits are available,2,14,16 and one study on interlaboratory variability in pediatric critical values was recently published.12



Critical Diagnoses in Anatomic Pathology Anatomic pathologists evaluate organs, tissues, and cellular specimens and provide diagnoses when abnormal findings are observed. Preanalytic and analytic processes (eg,



gross examination, tissue slicing, staining, and immunohistochemical analysis) often mean that hours to days may pass before a diagnosis can be made. In certain circumstances, the diagnosis suggests that “immediate treatment or prompt evaluation of the patient” may be indicated.35 This concept of critical diagnoses in surgical pathology and cytology (analogous to critical values in the clinical laboratory) has received significant attention in recent years.35-43 For example, several retrospective reviews and multiinstitutional surveys led to the creation of a list of possible critical diagnoses in anatomic pathology and cytology ❚Table 3❚.35-39,42,44 Even though these conditions were suggested as being important for immediate communication, the authors found an overall lack of consensus from participants on what might actually be included on such lists.35-37 In fact, there are no specific national guidelines as to what types of diagnoses in surgical pathology should qualify as critical. The concept of critical diagnoses, however, has been endorsed by the Association of Directors of Anatomic and Surgical Pathology, and a generic list of possible diagnoses was published in 2006 based on the aforementioned studies, with the caveat that any such list “needs to be customized to each individual hospital based on specific requests from clinicians and institutional factors such as the scope of services provided, case mix, acuity level, and protocols.”38,42,44 Finally, there is no consensus on how to actually report these diagnoses nor on the appropriate time frame for communication.38,40,45,46 In the absence of specific guidelines, it will remain necessary for institutions to establish local, customized protocols for handling critical diagnoses.



❚Table 3❚ Examples of Possible Critical Diagnoses in Anatomic Pathology35-39,42,44 Surgical pathology Crescents in >50% of glomeruli in a kidney biopsy specimen Vasculitis Bacteria in a heart or bone marrow specimen Select organisms in immunocompromised patients Uterine contents without villi or trophoblast Fat in an endometrial curettage Mesothelial cells in a cardiac biopsy specimen Fat in colonic endoscopic polypectomy specimens Transplant rejection Malignancy in superior vena cava syndrome Neoplasms causing paralysis Significant disagreement between frozen section and final diagnoses Cytology Unexpected malignancy Malignancy in critical places that can cause spinal cord injury Disagreement between immediate and final interpretations of FNA specimens Fungi in an FNA specimen from an immunocompromised patient The finding of certain microorganisms in any patient FNA, fine-needle aspiration.



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The importance of using critical value data to better understand laboratory process and preanalytic error cannot be overemphasized. For example, one program identified a specimen transport issue that led to falsely elevated K+ results in some patients.27 Changing the transport requirements decreased the number of critical high K+ results. This change not only enhanced the quality of the laboratory’s performance but also eased the burden of unnecessary critical value calls. Analysis of critical value limits can also be used to estimate the impact on call frequency that would result from changing threshold requirements.10 Analysis can reveal differences in critical value patterns by patient location (eg, falling hematocrit values on surgical services vs low K+ values on medical services).30 This information could be used, for example, in the evaluation of new point-of-care programs. Others have used critical values analysis in studies of adverse events and clinical activity at discrete hospital locations.34 Critical value audits provide tremendous information on laboratory processes, and they are a great starting point for quality improvement initiatives.



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Conclusion



Case Summary After being unable to contact a covering physician, the laboratory technologist paged the on-call pathology resident. The resident had access to the outpatient EMR and noticed that a cardiology fellow (and not the patient’s primary attending physician) wrote the clinic notes. The on-call cardiology fellow was paged by the resident and stated that she was familiar with the patient. She accepted the critical results, performed appropriate read-back, and contacted the patient for clinical follow-up. The resident called back the laboratory technologist and provided necessary information for documentation of the critical value notification. On investigation the next day, it was determined that a new member of the outpatient office staff did not know how to set the telephone system appropriately to forward calls to the answering service. The telephone (and pager) directory was updated for all physicians at this clinic. From the 1Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, Cornell University, and New York-Presbyterian Hospital, New York, NY; and 2Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT, and the Pathology and Laboratory Medicine Service, VA Connecticut Healthcare System, West Haven. Address reprint requests to Dr Genzen: Weill Cornell Medical College, 525 E 68th St, F-705, New York, NY 10065.



References 1. Lundberg G. When to panic over an abnormal value. Med Lab Obs. 1972;4:47-54.



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2. Burtis C, Ashwood E, Bruns D, eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 4th ed. St Louis, MO: Elsevier Saunders; 2006. 3. College of American Pathologists. Laboratory General Checklist [components GEN.41320, GEN.41330, and GEN.41340]. Available at www.cap.org. Accessed August 6, 2010. 4. The Joint Commission. Accreditation Program: Laboratory, National Patient Safety Goals (NPSG.02.03.01). http://www. jointcommission.org/. Accessed July 12, 2010. 5. International Organization for Standardization. ISO 15189:2007: medical laboratories: particular requirements for quality and competence [items 5.5.3n, 5.8.7, and 5.8.8]. Available at www.iso.org. Accessed August 7, 2009. 6. Medicare, Medicaid, and CLIA Programs: laboratory requirements relating to quality systems and certain personnel qualifications. Fed Regist. 2003;68:3639-3714. Codified at 42 CFR §493. 7. Barenfanger J, Sautter RL, Lang DL, et al. Improving patient safety by repeating (read-back) telephone reports of critical information. Am J Clin Pathol. 2004;121:801-803. 8. Rensburg MA, Nutt L, Zemlin AE, et al. An audit on the reporting of critical results in a tertiary institute. Ann Clin Biochem. 2009;46:162-164. 9. Emancipator K. Critical values: ASCP practice parameter. Am J Clin Pathol. 1997;108:247-253. 10. Dighe AS, Rao A, Coakley AB, et al. Analysis of laboratory critical value reporting at a large academic medical center. Am J Clin Pathol. 2006;125:758-764. 11. Parl FF, O’Leary MF, Kaiser AB, et al. Implementation of a closed-loop reporting system for critical values and clinical communication in compliance with goals of the Joint Commission. Clin Chem. 2010;56:417-423. 12. Gong Y, Adeli K. A national survey on pediatric critical values used in clinical laboratories across Canada. Clin Biochem. 2009;42:1610-1615. 13. Howanitz PJ, Steindel SJ, Heard NV. Laboratory critical values policies and procedures: a college of American Pathologists Q-Probes study in 623 institutions. Arch Pathol Lab Med. 2002;126:663-669. 14. Wagar EA, Friedberg RC, Souers R, et al. Critical values comparison: a College of American Pathologists Q-Probes survey of 163 clinical laboratories. Arch Pathol Lab Med. 2007;131:1769-1775. 15. Piva E, Sciacovelli L, Zaninotto M, et al. Evaluation of effectiveness of a computerized notification system for reporting critical values. Am J Clin Pathol. 2009;131:432-441. 16. Kost GJ. Table of critical limits. MLO Med Lab Obs. 2004;36(13 suppl):6-7. 17. Kost GJ. Critical limits for urgent clinician notification at US medical centers. JAMA. 1990;263:704-707. 18. Kost GJ. Clinical and professional reference guides: table of critical limits. MLO Med Lab Obs. 2001;33:12-13. 19. Lusky K. Critical values: looking more closely at calls, cutoffs. CAP Today. November 2008:80. 20. Kost GJ. Critical limits for emergency clinician notification at United States children’s hospitals. Pediatrics. 1991;88:597-603. 21. Kost GJ. The significance of ionized calcium in cardiac and critical care: availability and critical limits at US medical centers and children’s hospitals. Arch Pathol Lab Med. 1993;117:890-896.



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Along with the entire team of personnel involved in critical value notifications, pathologists and/or laboratory directors have an important role in many aspects of critical value reporting. They are involved in establishing and updating the critical value lists and policies (in consultation with clinicians and institutional medical boards), they assist in critical value escalation and interpretations, they are responsible for ensuring compliance with TJC- and CAP-required documentation, and they can use critical values audits to improve overall laboratory performance. Technological advancements will certainly alter the way in which critical value notifications are made, but these will not change the overall responsibility of pathologists and laboratory directors for ensuring compliance with critical value notification requirements. A recent CAP Today Q&A discussion on critical value notification concluded by stating that “a focus on building a patient-centric system requires strong pathologist leadership to ensure a safe and reliable system.”31 As such, a strong commitment to the critical value notification process can enhance overall patient care and should be a focus of ongoing quality improvement.



Pathology Consultation / Special Article



35. Pereira TC, Liu Y, and Silverman JF. Critical values in surgical pathology. Am J Clin Pathol. 2004;122:201-205. 36. Pereira TC, Clayton AC, Tazelaar HD, et al. Critical values in cytology. Diagn Cytopathol. 2006;34:447-451. 37. Pereira TC, Silverman JF, LiVolsi V, et al. A multiinstitutional survey of critical diagnoses (critical values) in surgical pathology and cytology. Am J Clin Pathol. 2008;130:731-735. 38. Silverman JF. Critical diagnoses (critical values) in anatomic pathology. Am J Clin Pathol. 2006;125:815-817. 39. Silverman JF, Pereira TC. Critical values in anatomic pathology. Arch Pathol Lab Med. 2006;130:638-640. 40. Visscher DW. What values are critical [editorial]? Am J Clin Pathol. 2008;130:681-682. 41. Huang EC, Kuo FC, Fletcher CD, et al. Critical diagnoses in surgical pathology: a retrospective single-institution study to monitor guidelines for communication of urgent results. Am J Surg Pathol. 2009;33:1098-1102. 42. Silverman JF, LiVolsi VA, Fletcher CD, et al. Critical diagnoses (critical values) in anatomic pathology. Am J Surg Pathol. 2006;30:897-899. 43. Allen TC. Critical values in anatomic pathology? Arch Pathol Lab Med. 2007;131:684-687. 44. Silverman JF, Fletcher CD, Frable WJ, et al. Critical diagnoses (critical values) in anatomic pathology. Hum Pathol. 2006;37:982-984. 45. LiVolsi VA, Leung S. Communicating critical values in anatomic pathology. Arch Pathol Lab Med. 2006;130:641-644. 46. LiVolsi VA. Critical values in anatomic pathology: how do we communicate [editorial]? Am J Clin Pathol. 2004;122:171-172.



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22. Massachusetts General Hospital Pathology Service. Laboratory Handbook. http://mghlabtest.partners.org/ CriticalValues.htm. Accessed September 27, 2010. 23. Brigham and Women’s Hospital. Clinical Laboratory Manual. http://www.brighamandwomens.org/clinicallabs/medical/ resources.aspx. Accessed October 3, 2010. 24. Mayo Medical Laboratories. Critical Values and Semi-Urgent Results. http://www.mayomedicallaboratories.com/articles/ criticalvalues/index.html. Accessed October 2, 2010. 25. Yale-New Haven Hospital. Laboratory Manual. https:// labmanual.ynhh.org/. Accessed October 1, 2010. 26. Valenstein PN, Wagar EA, Stankovic AK, et al. Notification of critical results: a College of American Pathologists Q-Probes study of 121 institutions. Arch Pathol Lab Med. 2008;132:1862-1867. 27. Dighe AS, Jones JB, Parham S, et al. Survey of critical value reporting and reduction of false-positive critical value results. Arch Pathol Lab Med. 2008;132:1666-1671. 28. Dighe AS. Making the right calls on critical values, tests. CAP Today. August 2008:12. 29. Etchells E, Adhikari NK, Cheung C, et al. Real-time clinical alerting: effect of an automated paging system on response time to critical laboratory values: a randomised controlled trial. Qual Saf Health Care. 2010;19:99-102. 30. Kuperman GJ, Teich JM, Tanasijevic MJ, et al. Improving response to critical laboratory results with automation: results of a randomized controlled trial. J Am Med Inform Assoc. 1999;6:512-522. 31. Hernandez JS. Q & A. CAP Today. May 2010:94. 32. Singh H, Vij MS. Eight recommendations for policies for communicating abnormal test results. Jt Comm J Qual Patient Saf. 2010;36:226-232. 33. Wagar EA, Stankovic AK, Wilkinson DS, et al. Assessment monitoring of laboratory critical values: a College of American Pathologists Q-Tracks study of 180 institutions. Arch Pathol Lab Med. 2007;131:44-49. 34. Jenkins JJ, Crawford JM, Bissell MG. Studying critical values: adverse event identification following a critical laboratory values study at the Ohio State University Medical Center. Am J Clin Pathol. 2007;128:604-609.