Acute Kidney Injury and Kidney Replacement Therapy in the Critically Ill Patient
Patient Case
Questions 4β6 pertain to the previous case.
F.B. is a 68-year-old man (weight 70 kg) admitted to your ICU with fever, elevated WBC, respiratory failure requir-
ing mechanical ventilation, and norepinephrine to support his blood pressure. His medical history is significant
for chronic back pain, diabetes, and hypertension. He takes both enalapril and glipizide once daily, as well as
acetaminophen as needed. Before this admission, he had otherwise been healthy, seeing his primary care provider
about 1 week ago. At that time, his blood pressure was 140/80 mm Hg, and his A1C was 5.2%. His laboratory
workup was also unremarkable: WBC 5.0 x 103 cells/mm3, BUN 7 mg/dL, and SCr 0.9 mg/dL. Today, his WBC is
24 x 103 cells/mm3, BUN 38 mg/dL, and SCr 3.2 mg/dL, with 325 mL of UOP since his admission 24 hours ago. It
is determined that F.B. needs KRT to manage his volume and control his metabolic derangements. He is currently
receiving norepinephrine with a mean arterial pressure of 65 mm Hg.
Which renal replacement mode will most likely be chosen?
F.B. will be initiated on a new extended-spectrum cephalosporin with limited information available for its
use during continuous KRT. Given the following parameters, estimate the drugβs SC: MW 480 Da, positively
charged drug, Vd 1.9 L/kg, protein binding 12%.
Given the calculated SC, estimate the new cephalosporinβs clearance during continuous KRT if the prescrip-
tion is CVVH, blood flow 200 mL/minute, ultrafiltration rate 2000 mL/hour, 100% pre-filter replacement
fluids, and use of a high-flux, high-efficiency dialyzer.