Similar to critical values (CVs) in clinical pathology, occasional diagnoses in surgical pathology and cytology could require immediate notification of the physician to rapidly initiate treatment. However, there are no established CV guidelines in anatomic pathology. A retrospective review of surgical pathology reports was recently conducted to study the incidence of CVs in surgical pathology and to survey the perceptions of pathologists and clinicians about CVs in surgical pathology, with a similar analysis of CVs performed in cytology. The results indicated that CVs in surgical pathology and cytology are uncommon but not rare and that there is a wide range of opinion among pathologists and between pathologists and clinicians about the need for an immediate telephone call and about the degree of urgency. It was obvious from the study that there is a lack of consensus in identifying what constitutes surgical pathology and cytology CV cases. Since the Institute of Medicine's report on medical errors, there has been an increasing number of initiatives to improve patient safety. Having guidelines for anatomic pathology CVs could enhance patient safety, in contrast to the current practice in which CV cases are managed based on common sense and on personal experience. Therefore, a discussion involving the pathology community might prove useful in an attempt to establish anatomic pathology CV guidelines that could represent a practice improvement.

The concept of critical values (CVs), first introduced by Lundberg,1 is defined as “a pathophysiologic derangement at such variance with normal as to be life threatening if therapy is not instituted immediately.” Following the 1972 publication of Lundberg's article, the Practice Assessment Committee and the Board of Directors of the American Society of Clinical Pathology presented practice parameter guidelines that included a generic CV list derived from interlaboratory surveys.2 They recommended that every laboratory customize its list to meet the needs of the organization and that an institutional committee approve and periodically review and revise this list. They also recommended that there should be strict semantic interpretation of CVs and a process for reporting by telephone or by alphanumeric page any laboratory test results with CVs.2 

The Clinical Laboratory Improvement Amendments of 1998, section 493.1109, states that “the laboratory must develop and follow written procedures for reporting eminent life-threatening laboratory results or panic values.”3 In addition, “the laboratory must immediately alert the individual or entity requesting the test or the individual responsible for utilizing the test results when any test results indicate an eminent life-threatening condition.”4 In the College of American Pathologists Laboratory Accreditation Program, the laboratory general checklist asks “does the laboratory have procedures for immediate notification of a physician when the results of certain tests are within established ‘critical’ ranges?”5 The Joint Commission on Accreditation of Healthcare Organizations' standard LD 3.2.1 notes that “approved criteria are established for the immediate notification of the responsible practitioner when critical limits of specified test results are exceeded.”6 In addition, a 2005 national patient safety goal of the Joint Commission on Accreditation of Healthcare Organizations is “improved effectiveness of communication among care givers.”6 The measure assesses and, if appropriate, takes action “to improve the timeliness of reporting, and the timeliness of receipt by a responsible licensed care giver, of critical test results and values.”6 

Following the introduction of the CV concept and these regulatory requirements, the practice of notifying physicians of CVs has become the standard of practice in clinical pathology, with well-established guidelines about which laboratory results require the technologist to immediately contact the clinician or the nurse responsible for the patient.7–12 An example of a CV would be a very low potassium level, because hypokalemia is associated with cardiac arrhythmia and sudden death. However, in surgical pathology and cytology, there are no guidelines and there is scant literature addressing the concept of CVs. In addition, anatomic pathology results are not measured in numbers, although there are certain diagnoses that could require immediate treatment or prompt evaluation of the patient, satisfying the Lundberg1 concept of CVs. An example of a possible CV in anatomic pathology is the presence of adipose tissue in an endometrial biopsy specimen, which almost always represents omentum or extrauterine pelvic soft tissue and indicates perforation of the uterus.13 

In surgical pathology and cytology, common sense and the personal experience of the pathologist determine when immediate notification of the physician is needed, because there are no established guidelines to help the pathologist. Therefore, to better evaluate the need for CVs in anatomic pathology, a study was conducted to determine the prevalence and the pathology management of CVs in surgical pathology and to survey the perceptions of pathologists and clinicians about CVs in anatomic pathology.14 The investigators in that study first undertook an analysis of the prevalence of CVs in surgical pathology by conducting a retrospective review of surgical pathology reports at Allegheny General Hospital, Pittsburgh, a large tertiary academic teaching hospital. They reviewed all surgical pathology reports during a 2-month period for possible CV cases and documented the telephone calls to clinicians, the dates of the telephone calls, the dates the specimens were received, and the dates the reports were signed out. In the cases without documentation of a telephone call, the clinical history provided on the surgical pathology requisition was reviewed for justification for the absence of a call (eg, the clinical history implied that the clinician already knew the diagnosis). The authors also analyzed and compared the perceptions about CV cases by conducting a survey among pathologists and clinicians of different specialties. The participants consisted of 11 pathologists (6 at Allegheny General Hospital and 5 expert senior surgical pathologists from other tertiary institutions), along with 5 senior physician specialists in surgical oncology, internal medicine, gynecology, medical oncology, and infectious disease at Allegheny General Hospital.14 Based on personal experience, the authors of the study identified 11 possible surgical pathology CV cases, including crescents in renal biopsy specimens, vasculitis, bacteria in heart valves or bone marrow, organisms in an immunocompromised patient, fat in an endometrial curettage, uterine contents without villi or trophoblasts in the workup of a patient suspected to be pregnant, mesothelial cells in a heart biopsy specimen, transplant rejections, malignancy in superior vena cava syndrome, neoplasms potentially causing paralysis, and large vessels in a core biopsy specimen, and listed them on the survey form. The participants were then asked to grade from 1 to 4 the need for an immediate telephone call for the 11 given diagnoses. The grading system was as follows: (1) There is no need for a telephone call, and this report can be sent within a standard time frame and in a routine manner. (2) A telephone call should be made, but the information in the report will not change the patient's treatment. (3) An immediate telephone call should be made, but it is uncertain whether the report will change the patient's treatment or management. (4) An immediate telephone call should be made because prompt treatment or immediate evaluation of the patient is needed. In addition, there was free text space for the participants to list any additional CV cases in which immediate telephone calls would be necessary.14 

During a 2-month period, 2659 consecutive surgical pathology reports were reviewed, and 13 CV cases (0.5%) were identified, including 2 cases of crescents in renal biopsy specimens, 3 cases of vasculitis, 4 cases of bacteria in tissue, 1 case of cytomegalovirus pneumonia in an immunosuppressed patient, 1 case of uterine contents without villi in a patient suspected to be pregnant, and 2 cases of transplant rejections.14 Only 4 documented telephone calls in 13 cases were noted in the surgical pathology reports, with 3 of the telephone calls placed at least 1 day before official sign-out. Two other cases had documented clinical histories in the requisitions that implied previous knowledge of the diagnosis. Most of the participants agreed that bacteria in heart valves or bone marrow and organisms in an immunocompromised patient represented surgical pathology CV cases. All participants agreed on the need for a telephone call when crescents in renal biopsy specimens, fat in an endometrial curettage, and malignancy in superior vena cava syndrome were identified but differed on the degree of urgency for notification. There was strong disagreement about listing vasculitis as a CV. Additional CV cases identified by clinicians included unexpected malignancy, change in diagnosis in inflammatory bowel disease, acid-fast organisms in tissue biopsy specimens, and invasive aspergillosis. Additional CV cases identified by pathologists included discordance between the frozen section and permanent section diagnosis, all fine-needle aspiration diagnoses, fat in snare colon biopsy specimens, polyomavirus, hydatiform mole, hemophagocytic syndrome, necrotizing fasciitis, and hematologic malignancies such as an acute leukemia.

The investigators concluded that CVs in surgical pathology are uncommon but not rare and that most surgical pathology CV cases had no documentation of telephone calls in the surgical pathology report and that a history was often not provided.14 There was also a range of opinion among pathologists and between pathologists and clinicians about the need for an immediate telephone call and about the degree of urgency. It was obvious from the study that there is a lack of consensus in identifying what constitutes surgical pathology CV cases.

Recently, a similar analysis of CVs in cytology was performed based on 2000 cytology reports from Allegheny General Hospital and from Mayo Clinic, Rochester, Minn, consisting of 200 gynecologic, 400 nongynecologic, and 400 fine-needle aspiration reports from each institution to identify the prevalence of cytology CVs.15 Critical value cases included unexpected malignancy, disagreement between preliminary and final fine-needle aspiration diagnoses, and organisms in nongynecologic and fine-needle aspiration specimens. Fifty-two CV cases (2.6%) were identified, including 1 (0.3%) of 400 gynecologic, 15 (1.9%) of 800 nongynecologic, and 36 (4.5%) of 800 fine-needle aspiration reports. Forty-two cases were unexpected malignancies, 5 were disagreements between preliminary and final fine-needle aspiration diagnoses, and 5 were organisms in nongynecologic fine-needle aspiration specimens. Thirty of 52 reports had documented telephone calls to the clinician. The researchers also undertook a survey among pathologists and clinicians about cytology CVs, including 13 pathologists and 13 clinicians at Allegheny General Hospital and Mayo Clinic and 9 national senior cytopathologists. The survey included 18 different CVs, with the grading of urgency for telephone calls ranging from (1) no telephone call needed, (2) no telephone call needed within 24 hours, and (3) notify as soon as possible. Most of the surveyed participants agreed that a new diagnosis of malignancy, especially an unexpected malignancy or one involving a critical site, required a telephone call. Other cytology CVs included microorganisms in immunosuppressed patients and disagreement between preliminary and final fine-needle aspiration diagnoses. There was a greater difference of opinion when a new metastasis was identified in a patient with a known primary and when an organism was identified in an immunocompetent patient. All participants agreed that no telephone call was needed when polyomavirus was identified in a urine specimen or when a new diagnosis of a high-grade squamous intraepithelial lesion was made. Additional CV cases suggested by the survey participants included herpes in a Pap smear in a pregnant patient, atypical glandular cells of uncertain significance in Pap smears, amended reports, very unusual tumors, disagreement with outside slide interpretation, infection or malignancy in orbital fine-needle aspiration samples, discrepancy between clinical expression and pathologic interpretation, and delay in signing out the cytology report. The investigators concluded from the study that CV cases are not uncommon in cytology (2.6%) but that pathologists often do not call in these cases or that a telephone call was not documented. Generally, good agreement was found among pathologists and clinicians about which situations would require notification of the clinician and about the degree of urgency, although there were still differences of opinion.

In the 2004 surgical pathology study, MEDLINE was searched from 1966 to mid June 2003 for the terms pathology/biopsy and critical/panic/alert values/limits or contact/contacted/called/phone calls/surgeon/clinician/physician/doctor/notifications/emergencies.14 The review identified no peer-reviewed articles specifically addressing CVs in surgical pathology, although Rosai and Ackerman's Surgical Pathology states that “when an urgent decision needs to be made on the basis of a pathologic finding, the clinician should not have to wait for the information to reach him by standard printed report.”16 However, there were no specific examples given of what would constitute a CV. In Diagnosis of Endometrial Biopsies and Curettings: A Practical Approach, Mazur and Kurman13 state that, when adipose tissue in an endometrial biopsy specimen is identified, it indicates that a perforation of the uterus has occurred and that the clinician should be immediately notified.

Since the Institute of Medicine's report on medical errors,17 several initiatives have been instituted to improve patient safety. We believe that having guidelines for anatomic pathology CVs can improve patient safety, in contrast to the current practice in surgical pathology and cytology, in which CV cases are managed based on common sense and on personal experience. Although some pathology laboratories have written policies addressing the communication of medically CVs in anatomic pathology,18 there are no established national guidelines, and our findings herein show substantial differences of opinion among pathologists and between pathologists and clinicians about what constitutes an anatomic pathology CV case and about the degree of urgency for notification. Therefore, establishing anatomic pathology guidelines for CV cases that would require immediate contact of the clinician could represent a practice improvement. It is also apparent that clinicians want quick notification of abnormal findings. Recently, the College of American Pathologists published the results of a Q-Probe study that assessed physician satisfaction with anatomic pathology laboratory services.18 Among the aspects that were evaluated, the item with the lowest satisfaction score was related to poor communication, including timeliness of reporting, communication of relevant information, and notification of significant abnormal results. In February 2005, at the 15th Annual Meeting of the Association of Directors of Anatomic and Surgical Pathology, in San Antonio, Tex, a committee was established in an attempt to formulate anatomic pathology CV guidelines.

Finally, LiVolsi19 has noted other issues that need to be addressed concerning CVs, including (1) whether we can arrive at a consensus for anatomic pathology CVs and (2) what obligations laboratories have to communicate CVs, how pathologists should communicate the critical information (ie, telephone call, e-mail, or other method), and whom pathologists should call. Although these are daunting challenges, we believe that establishing generic anatomic pathology CV guidelines is a good starting point, similar to what was done in clinical pathology. Using a generic list as a template, the types of CV cases can be customized at each hospital based on specific requests from clinicians and on institutional factors such as scope of services, case types, acuity levels, and protocols. Therefore, similar to the establishment of CVs in clinical pathology at individual institutions, consultations with relevant clinical services in the development of anatomic pathology CVs are important. Analogous to clinical pathology, it is important to avoid overuse of CVs and to clearly delineate non-CV cases.

In conclusion, we believe that this is a task that needs to be undertaken, because surgical pathology and cytology examinations identify abnormalities that can be at variance from normal findings, may be potentially life-threatening, and would require rapid corrective action for improved patient outcome. Finally, we concur with LiVolsi19 that “in order to avoid medical errors and to serve patients in an efficient and judicious manner, the discussion needs to be brought to the entire pathology community.”

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Presented in part at the annual meeting of the Association of Directors of Anatomic and Surgical Pathology, San Antonio, Tex, February 26, 2005, as part of a symposium entitled “Error Reduction and Critical Values in Anatomic Pathology.”

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

Author notes

Reprints: Jan F. Silverman, MD, Department of Pathology and Laboratory Medicine, Allegheny General Hospital, 320 E North Ave, Pittsburgh, PA 15212 (jsilverm@wpahs.org)