Arterial–venous blood gas correlation and prognostic significance in critically ill pediatric patients


Altun I., AYGÜN F. D., AYGÜN F.

Pediatrics International, cilt.68, sa.1, 2026 (SCI-Expanded, Scopus) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 68 Sayı: 1
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1111/ped.70383
  • Dergi Adı: Pediatrics International
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CINAHL, EMBASE, MEDLINE
  • Anahtar Kelimeler: blood gas analysis, intensive care units, pediatric, prognosis
  • İstanbul Üniversitesi-Cerrahpaşa Adresli: Evet

Özet

Background: This study aimed to evaluate the correlation between arterial and venous blood gas parameters in critically ill pediatric patients and to assess their association with prognostic indicators and clinical outcomes. The feasibility of using venous blood gas analysis as a less invasive alternative to arterial sampling was also explored. Methods: A prospective observational study was conducted in the PICU. Simultaneous arterial and venous blood gas samples were collected on the first and second days of admission. Associations with PRISM and PELOD, mortality, and the need for critical care interventions were investigated using correlation analyses and ROC curves. Results: Among 104 patients, arterial and venous pH, pCO2, HCO3, and base excess showed strong correlations (r > 0.8), while lactate levels showed moderate agreement. Venous PCO2 and lactate were significantly higher in nonsurvivors and correlated with PRISM and PELOD scores. On both days, lactate levels and venous PCO2 were predictive of mortality (AUCs: 0.660–0.744). The Pv–aCO2 difference was significantly elevated in nonsurvivors on the first day. Oxygenation parameters (SpO2, PaO2, O2Hb) showed weak correlation, indicating the continued need for arterial sampling in hypoxemic conditions. Conclusions: Venous blood gas analysis reliably reflects acid–base status and may be an alternative to arterial sampling for selected parameters in critically ill pediatric patients. Venous PCO2, lactate levels, and Pv–aCO2 may be useful for risk stratification and longitudinal monitoring in the PICU. However, arterial analysis remains essential for oxygenation, and venous sampling should not substitute arterial measurements when evaluating hypoxemia.