Defined as a symptomatic episode of delirium, coma, nausea, vomiting, constipation, muscle weakness, hypertension, bradycardia, deemed attributable to hypercalcemia with a confirmed systemic ionized calcium \> 1.5mmol/L.

Arterial pH \> 7.55 and bicarbonate \> 30 mmol/L in the absence of exogenous bicarbonate administered

Serum sodium (Na) level \> 150 mmol/L and \> 5 mmol/L rise in systemic Na above the prescribed CRRT fluids. Na level in the absence of hypertonic intravenous Na infusion

Bleeding resulting in more than 2 g/dL drop in hemoglobin (Hgb) in 24-hour period or need for transfusion

Patients with impaired citrate metabolism or citrate overdose can exhibit citrate accumulation. Symptomatic citrate accumulation presents with symptoms of tetany/spasms, seizures, systemic hypocoagulability, hypotension, or cardiac events; and should be confirmed with: 1. A total-to-ionized calcium ratio \> 2.5; OR 2. A total-to-ionized calcium ratio greater than 2.25 together with one or more of the following criteria: 1. an increase in calcium supplementation, 2. decreasing systemic ionized calcium, and 3. metabolic acidosis. When a clinical presentation is possibly associated with an abnormal concentration of systemic ionized calcium or an altered acid-base balance, the labs ({Calcium: systemic ionized calcium, post-filter ionized calcium and total calcium}, bicarbonate, sodium, potassium, magnesium, phosphate) should be checked immediately.