Definition, Validation, and Defining Characteristics of "Impaired Gas Exchange" Nursing Diagnosis: A Systematic Review and Meta-Analysis.

Background"Impaired Gas Exchange" (NANDA-I 00030) is a prevalent respiratory nursing diagnosis, yet individual validation studies report conflicting findings regarding the frequency and diagnostic accuracy of its defining characteristics (DCs).ObjectiveTo synthesize evidence on the frequency and diagnostic accuracy of the DCs of the nursing diagnosis "Impaired Gas Exchange".MethodsA systematic review and meta-analysis was conducted in accordance with PRISMA 2020 guidelines. A systematic search was performed across six databases, including PubMed, CINAHL, Scopus, Web of Science, Embase, and ProQuest, from each database's start date through December 14, 2025, to find relevant studies. Keywords covered "Impaired Gas Exchange," "Pulmonary Gas Exchange," "Nursing Terminologies," "NANDA-International," and "Nursing Diagnosis." Methodological quality was assessed using QUADAS-2. Diagnostic accuracy parameters were pooled using bivariate random-effects models in Meta-DiSc 1.4.ResultsThirteen studies (n = 2,346) were included. Pooled frequencies were calculable for 12 of 19 NANDA-I DCs; the most prevalent were hypoxia (96%; 95% CI: 94-98%), tachypnea (48%; 95% CI: 43-53%), hypercapnia (44%; 95% CI: 15-100%), and tachycardia (42%; 95% CI: 4-80%). Three studies were eligible for diagnostic accuracy meta-analysis across seven DCs. Hypoxemia had the highest sensitivity (0.94). Irritable mood had the highest specificity (0.95). Dyspnea performed poorly (DOR = 0.46).ConclusionObjective physiological indicators, particularly hypoxemia, hypoxia, and hypercapnia, were the most frequent and diagnostically accurate DCs. Future multicentre studies using standardized definitions and objective reference standards are needed to refine the diagnostic profile of "Impaired Gas Exchange".