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Wen Jun Liu¹Dong Milan²Jing Li^1*Guoying Zhang³Ju Chen³Jianyu Jiang⁴Ling Duan⁴Daoxue Xiong⁴Bo Huang⁵Yingbo Zou⁵Fuyan Liu⁵Hong-Min Fu⁶Kai Yu⁶

• ¹Children‘s Hospital of Chongqing Medical University, Chongqing, China
• ²Chongqing Health Center for Women and Children, Chongqing, Chongqing, China
• ³Chengdu Women and Children’s Central Hospital, Chengdu, Sichuan Province, China
• ⁴Chongqing Three Gorges Central Hospital, Chongqing, China
• ⁵First People’s Hospital of Zunyi, Zunyi, Guizhou Province, China
• ⁶Kunming Children's Hospital, Kunming, Yunnan Province, China

The available evidence on tight glycemic control is conflicting, while the interaction between glucose and lactate in critically ill children remains unclear.Objective: To explore the potential role of hyperlactatemia (HL) in modulating the relationship between stress hyperglycemia (SHG) and poor outcomes, aiming to establish tailored glucose targets in critically ill children.This was a secondary analysis of a prospective observational cohort study conducted in five Pediatric Intensive Care Units (PICU) in southwestern China (ChiCTR2000030846). The interaction effect between glucose and lactate metrics concerning outcomes and subsequent subgroup regression analysis was conducted. SHG was defined as glucose > 150 mg/dL(8.3mmol/L) and HL as lactate > 2 mmol/L.A cohort of 433 pediatric patients with 4885 arterial blood gas measurements were finally enrolled. 90 (20.8%) cases died within 28 days of PICU admission. Significant interaction effects between SHG and HL on outcomes were observed (p < 0.05). In the non-HL group, SHG was not an independent predictor of 28-day mortality (p = 0.656) and was not correlated with either 28-day ventilator-free days (p = 0.916) or 28-day ICU-free days (p = 0.914). In contrast, in the HL group, SHG was independently associated with 28-day mortality (OR 3.55, 95% CI 1.62~7.80, p = 0.002) and correlated with a reduction of 5.04 28day ventilator-free days (p = 0.003) and 4.10 28-day ICU-free days (p = 0.004).Conclusions: HL potentially modulates the correlation between SHG and poor outcomes in pediatric critically ill patients. Combined SHG and HL are associated with poor outcomes, whereas SHG without HL is not.