Title
Establishing an Evidence Base for Critical Laboratory Value Thresholds
Publication Date
2014
Journal Title
Am J Clin Pathol
Abstract
Objectives: Critical values denote laboratory test results indicating a life-threatening situation. The outcomes of this premise have not been rigorously evaluated. Methods: Five years of inpatient admissions were examined for critical or "near-critical" results (total admissions = 165,066; total test results = 872,503). In-hospital mortality was examined as a fitnction of time and degree of test result abnormality. Results: Some critical value thresholds appropriately identified patients at risk for death (eg, elevated potassium). Other thresholds were too conservative (elevated hematocrit, hemoglobin) or not conservative enough (elevated lactate). Mortality risk for most critical values was time dependent, but some critical values showed no temporal effect on mortality (elevated activated partial thromboplastin time [APTT], international normalized ratio [INR], and glucose). Following an initial critical result, further worsening was associated with increased mortality. Prior hospital admission within 30 days was a predictor of lower mortality for some (elevated APTT, INR, potassium, and sodium; low glucose, hem atocrit, hemoglobin, and potassium) but not other critical values (elevated lactate, glucose, hematocrit, and hemoglobin; low sodium). Conclusions: Only a subset of laboratory critical value thresholds was optimally chosen for increased risk of in-hospital mortality, with a time urgency for most but not all critical values. For many tests, a prior hospital admission imparted a decreased risk of in-hospital death.
Volume Number
142
Issue Number
5
Pages
617-628
Document Type
Article
EPub Date
2014/10/17
Status
Faculty, Northwell Resident
Facility
School of Medicine; Northwell Health
Primary Department
Pathology and Laboratory Medicine
PMID
DOI
10.1309/ajcpdi0fyz4unweq