Acute Diarrhea and Severe Dehydration in Children: Does Non-anion Gap Component of Severe Metabolic Acidemia Need More Attention?

Background: Despite significant loss of bicarbonate during acute diarrhea, pediatric data are scarce with acute diarrhea/severe dehydration (ADSD) and severe non-anion-gap metabolic acidemia (sNAGMA). We planned to study their clinical profile, critical care needs, and outcome. Patients: Children (1 month-12 years) with ADSD and sNAGMA (pH <7.2 and/or bicarbonate <15 mEq/L, and normal/mixed anion gap) admitted in Pediatric Emergency Department from January 2016 to December 2018 were enrolled. Children with pure high-anion-gap metabolic acidemia were excluded. Methods: Medical records were reviewed retrospectively. The primary outcome was time taken to resolve acidemia. Secondary outcomes were acute care area free days in 5 days (ACAFD(5)), and adverse outcome as composite of Pediatric Intensive Care Unit (PICU) admission and/or death. Results:Out of 929 diarrhea patients admitted for intravenous therapy, 121 (13%; median age, 4 months) had ADSD and sNAGMA. Median (IQR) pH was 7.11 (7.01-7.22); 21% patients had pH <7.00. Hyperchloremia (96%) and hypernatremia (45%) were common. About 12% patients each required inotropes and ventilation, while 58% had acute kidney injury (AKI). Median (IQR) time for resolution of acidemia among survivors was 24 (12, 24) hours. Thirty-two patients had adverse outcome. Higher grades of sNAGMA were associated with shock, AKI, coma, hypernatremia, hyperkalemia, adverse outcome, and lesser ACAFD5. Shock, ventilation, renal replacement therapy (RRT), and higher grades of sNAGMA were predictors of adverse outcome, with former two being independent predictors. Conclusions: Severe non-anion-gap metabolic acidemia in children with ADSD is associated with organ dysfunctions, dyselectrolytemias, and lesser ACAFDs. Resolution of acidemia took unacceptably longer time. Higher grades of sNAGMA were a predictor of adverse outcomes. Trials are suggested to assess the role of additional bicarbonate therapy.