Improving diagnostic accuracy of 72-hour supervised fasting test for hypoglycemia evaluation: A quality improvement project

Abstract

The 72-hour supervised fasting test (72-HSFT) remains the gold standard for investigating fasting hypoglycemia in patients without diabetes, which is a rare but potentially fatal clinical condition. However, testing inaccuracies often lead to diagnostic ambiguities and unnecessary healthcare expenditures. Baseline data collection over 1 year revealed that 66% of 72-HSFT tests at our institution were performed incorrectly, with dynamic hormones such as C-peptide being ordered four times per patient. The goal of this quality improvement project (QIP) was to reduce the frequency of unnecessary or incorrect 72-HSFT for hypoglycemia from 66% to 25% within 24 months. To achieve the goals of the QIP, educational interventions targeting patients, nurses, physicians, and laboratory staff on accurate 72-HSFT were implemented. Further interventions included the introduction of an auto-text protocol in Cerner^®, standardization of lab testing via a bundle order set for 72-HSFT, and multiple different models of interactive educational sessions. The project was conducted in the emergency department and the inpatient wards of the medicine department. In a plan-do-study-act 1 cycle, testing inaccuracy was reduced from 66% to 20%, with C-peptide orders reducing from 4 tests to 1.2 tests per patient. In plan-do-study-act 2, testing inaccuracy dropped to 0% with one C-peptide test ordered per patient. This QIP demonstrates that system-level changes, combined with conventional interventions such as targeted education and advanced technology-based interventions like clinical decision support tools, can significantly improve test accuracy and reduce unnecessary resource utilization in endocrinological diagnostics.

Keywords: Hypoglycemia; Fasting hypoglycemia; Quality improvement; 72-hour supervised fast; C-Peptide; Insulin

Core Tip: The 72-hour supervised fasting test is the cornerstone in evaluating fasting hypoglycemia, but remains vulnerable to procedural inconsistencies. This quality improvement project improved the diagnostic accuracy of the 72-hour supervised fasting test from 33.3% to 100% within two plan-do-study-act cycles. Key interventions included protocol standardization, an electronic medical records-integrated order bundle, targeted clinician and nursing education, and real-time clinical decision support prompts. These improvements were achieved without extending the length of stay, thus preserving patient flow. This project demonstrated promising sustainability and reproducibility in improving hypoglycemia evaluation, with multimodal effects on healthcare, including enhanced clinical outcomes, improved patient experiences, and potential cost reductions.