Visualization of Critical Limits and Critical Values Facilitates Interpretation

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Medical Diagnostics

Background:

• Critical limit and critical value testing are essential components of patient safety in healthcare.
• Monitoring changes in these laboratory thresholds is crucial for adapting clinical practice.

Purpose of the Study:

• To analyze critical limit and critical value lists from major US medical centers.
• To identify changes in quantitative critical limit thresholds since 1990.
• To document notification priorities and visualize data alongside clinical thresholds.

Main Methods:

• Systematic search and acquisition of 50 critical limit lists from US university hospitals and trauma centers.
• Statistical analysis using Kruskal-Wallis and Student's t-test to compare 1990 and 2024 data.
• Evaluation of notification priorities for qualitative and new listings.

Main Results:

• Significant differences found in critical limits for glucose, calcium, magnesium, CO2, blood gases, hematology, and coagulation tests between 1990 and 2024.
• Narrowed critical limit ranges and addition of new measurands observed.
• Cardiac biomarkers infrequently listed; point-of-care testing (POCT) data showed significant differences from main laboratory values.

Conclusions:

• Visualizing critical limit data enhances interpretation, potentially improving patient care.
• Standardizing and updating critical limits can reduce inconsistencies in healthcare delivery.
• The study highlights the evolving landscape of laboratory diagnostics and their clinical impact.