From “panic” to “critical” values: which path toward harmonization?

In the conventional “brain-to-brain loop” model, a body of evidence demonstrates that the risk of errors and patient harm is significantly decreased in processes that strictly develop inside the laboratory, whereas it remains relatively high at the beginning and at the end of the total testing process, which generally lie outside of the traditional laboratory environment [1, 2]. An increasing awareness of the need for standardizing and monitoring preanalytical activities has indeed generated positive revenues in terms of improved quality and decreased risk of errors [3]. Conversely, postanalytical processes are still more vulnerable to human error(s), noncompliance, and lack of harmonization, thus jeopardizing the quality of testing and – rather inevitably – posing serious risks for patient safety. Information technology (IT) has virtually eliminated the errors of manual data transcription, thus improving both efficiency and turnaround time between clinical laboratories and stakeholders. However, information overload can generate communication breakdowns, with delayed missed or even wrong diagnoses [4]. In postanalytical activities, critical values notification represents one of the main issues, but the complexity and importance of timely and safe delivery of this vital information require further efforts to improve harmonization throughout the process. In this issue of the journal, Zeng et al. [5] describe the results of a national survey on critical values notification in 599 Chinese institutions. The authors observed significant differences among laboratories, especially for limits and lists of the critical values as well as procedures for implementation. This reinforces the need for developing harmonization projects and developing best practice recommendations, which take into account correct definitions and terms [6, 7]. This should be achieved through projects based on consensus committees, professional groups (e.g., the ad hoc EFLM Working Group), published resources, or clinical studies. In particular, we need a general agreement on which tests and values should be considered “life-threatening”, and if – and how – we should harmonize decision levels and measurement units. Contextually, the harmonization of critical values may represent a cornerstone of educational and training process aimed to promote the culture of patient safety at medical schools. The genuine concept of “critical value”, originally described by George Lundberg [8, 9], has continued to be virtually unmodified for more than 40 years but merits some considerations.

First, critical values, as already defined by Lundberg [8], identify some laboratory results that are so “extremely” abnormal and are considered life threatening because they may be associated with a significant dangerous event unless a medical action is promptly established. The term “panic value” should likewise be definitively abandoned, as Lundberg himself reasonably criticized this term because “physicians are not supposed to panic over anything” [10].

Second, “critical value” should be distinguished from “critical test”. The latter term, according to the Joint Commission, identifies all tests that require rapid communication of results, irrespective of being normal, abnormal, or critical [11]. Because this is a novel and poorly explained concept, it deserves some further explanatory discussion. A “critical test” (e.g., troponin, D-dimer, hemoglobin) implies an immediate impact on clinical decision making independently of result. Laboratory results for such tests may not be associated with a serious risk for the patient’s safety, but they require timely and safe reporting. From this point of view, although current technological equipments and IT may provide timely laboratory results with improved performances, there is the need to better define mutual duties and responsibilities. In particular, the physician who requests a critical test has the responsibility to verify the availability of the result within consensually defined times, whereas the laboratory professionals must ensure appropriate and timely reporting.

Therefore, a consensus should be achieved by requesting physicians (namely those from emergency departments and intensive care units) on the reciprocal responsibilities to adopt when critical laboratory tests are requested and notified, although the list of critical tests and the notification/acknowledgment procedures may vary according to specific clinical settings and operational frameworks. The notification of critical tests should hence be considered as the procedure of promptly reporting results, thus avoiding delays that might potentially cause patient harm and the overload of alarms and calls, which can distract the activities of increasingly busy medical teams and emergency physicians.

Third, according to the National Goals of the Joint Commission, the leading target should aim to report critical results of tests and diagnostic procedures on an established time frame to the responsible licensed caregiver so that the patient can be promptly treated. In this context, a key point and still largely debated issue is the notification policies, in particular, the advantages of call centers vs. automated notification [12]. From a personal viewpoint, the main disadvantages of the call center option are the difficulties in performing audits and clinical outcomes evaluation, thus missing the final part of the cycle [13]. Because the ultimate goal of critical values notification is to improve the quality of patient care and safety, the missing link between notification and outcomes should be perceived as a dangerous breakdown. Nevertheless, the Laboratory Medicine Best Practices Workgroup of the Centers for Disease Control and Prevention (CDC), in its report, failed to formulate any kind of suggestion for or against the use of call centers or automated notification systems, and the debate is still ongoing [14]. The certification/accreditation programs, along with national or local regulatory legislations, have established standards that laboratories must comply with in order to support the basic quality for critical values notification in their institutions. Therefore, the possible harmonization of existing policies should not be based only on existing best practices but also on a benchmark regarding the “acceptable” time between the availability of critical values and their receipt by the responsible caregiver. Timeliness should be always correlated with clinical effectiveness, and procedures should provide the best clinical outcomes at the lowest reasonable cost. IT plays an increasingly dominant role in health care, is safer and more reliable than ever, and can support the clinician with rapid notification of a critical value, but information overload should be prevented.

The identification of suitable and reliable limits for the different parameters, which may inherently consider a kaleidoscope of biological (i.e., age, gender, ethnic origin, health status) and analytical issues (measuring principle, type of analyzer, etc.), is another important issue [15]. Here, the harmonization of thresholds seems ideal, and the use of longitudinal comparison of patient data appears to be a much more reasonable and clinically valid approach [16]. Finally, harmonization is expected to develop quality indicators regarding the policies of critical values communication and monitoring the timeliness of reporting critical values, and the need to evaluate the effectiveness of these procedures to provide evidence of improved notification assures good clinical outcomes. The postanalytical phase of the testing cycle still faces challenges and opportunities [17, 18].