The patient is a gravida 6, para 1. She is admitted after a cesarean section after an amniotic embolus. Her heart rate (HR) is more than 150 beats/min with a systolic BP less than 80 mm Hg

Question

Her temperature is 38 °C, and her condition has caused her to develop prerenal azotemia. The patient was fluid resuscitated through a double-lumen catheter, which was placed into her right femoral access, and started on vasopressors with a fair response (BP, 80/50 mm Hg; HR, 122 beats/min). Because of her diagnosis and a concern regarding fulminating sepsis, the patient was begun on CVVH. Which of the statements best describes CVVH?

a. Complete renal replacement therapy requiring large volumes of ultrafiltrate and filter replacement
b. Complete renal replacement therapy that allows removal of solutes and modification of the volume and composition of extracellular fluid to occur evenly over time
c. Involves the introduction of sterile dialyzing fluid through an implanted catheter into the abdominal cavity, which relies on osmosis, diffusion, and active transport to help remove waste from the body
d. Complete renal replacement therapy that allows an exchange of fluid, solutes, and solvents across a semipermeable membrane at 100 to 300 mL/hr

Answer 1

B
Continuous venovenous hemodialysis is indicated when the patient's clinical condition warrants removal of significant volumes of fluid and solutes. Fluid is removed by ultrafiltration in volumes of 5 to 20 mL/min or up to 7 to 30 L/24 hr. Removal of solutes such as urea, creatinine, and other small non-protein-bound toxins is accomplished by convection. The replacement fluid rate of flow through the continuous renal replacement therapy circuit can be altered to achieve desired fluid and solute removal without causing hemodynamic instability.