Dialysis is used to control the fluid balance and metabolic state of patients with kidney disease. Control of the metabolic state, via electrolytes, can be monitored using labs that are routinely drawn from patients undergoing continuous hemodialysis. Control of fluid removal is much more difficult. This study aims to determine whether changes in the blood pressure associated with breathing correlate with or predict intolerance to fluid responsiveness with continuous dialysis.

We hypothesize that a measurement of changes in blood pressure with breathing called arterial pulse pressure variation may be able to predict the ability to remove fluid during continuous renal replacement therapy.

Inclusion Criteria:

• age > 17 years old
• CVVHD renal replacement therapy
• indwelling arterial line

Exclusion Criteria:

• age < 18 years old
• pregnancy
• temperature < 34°C
• severe mechanical ventilator dyssynchrony
• cardiac arrhythmias precluding automated PPV measurement by ICU monitors
• non-pulsatile cardiac flow
• open thoracic cavity

Adult ICU patients requiring CVVHD who have an indwelling arterial line.