A 58-year-old male presents with septic shock secondary to a perforated bowel. He is intubated, on vasopressor support, and started on continuous renal replacement therapy (CRRT) due to acute kidney injury and fluid overload. Citrate is being used as the anticoagulant for CRRT. Over the past 24 hours, his arterial blood gas shows worsening metabolic acidosis (pH 7.15, HCO3 16), with a recent ionized calcium (iCa) level of 0.85 mmol/L (low). Despite adequate calcium replacement, his blood pressure remains unstable, requiring escalating doses of vasopressors.