Continuous Renal Replacement Therapy

1 Continuous Renal Replacement Therapy Jai Radhakrishnan, MD, MS. History of the CRRT program 1988. Open heart program Active transplant program Deep dissatisfaction with peritoneal dialysis in hemodynamically unstable patients Objectives Physiologic principles Patient Selection for CRRT. Modality Selection Prescription Variables Fluid Composition Management of Fluid and Electrolyte problems Controversies Basic Concepts Pressure Convection (Plasma water moves along pressure gradients). Continuous Renal Replacement Therapy SCUF. CVVH. CVVHD. CVVHDF. Therapy Options Access Return SCUF: Slow P. R. I. S. Continuous M. A. Ultra Filtration Maximum Patient Fluid Removal Effluent Rate = 2000 ml/hr Therapy Options Access Return CVVH.

2 Continuous P. R. Veno-Venous I. S. M. A. Replacement HemoFiltration Effluent Maximum Patient Fluid Removal Rate = 1000 ml/hr Therapy Options Access Dialysate Return CVVHD. P. Continuous R. I. S. M. Veno-Venous A. HemoDialysis Maximum Patient Fluid Removal Effluent Rate = 1000 ml/hr Therapy Options Access Dialysate Return CVVHDF P. R. Continuous I. S. M Replacement A. Veno-Venous HemoDiafiltration Maximum Pt. fluid Effluent removal rate = 1000 ml/hr A Case 35 year old female is s/p OHT, POD#1. Remains intubated, MAP 65 on Levo 20, Pit 3, Milrinone Urine output 10 (Intake 150ml/h). PAD 20. FiO2 ABG BMP 132 (Baseline ). Indications for Renal Replacement Standard indications Volume overload Hyperkalemia Metabolic Acidosis Uremic Platelet Dysfunction Uremic Encephalopathy Modality Selection Volume only SCUF.

3 CVVH. Solutes +/- Volume CVVHD. CVVHDF. Hypercatabolic CVVHDF. +/- Volume Prescription Variables Dialysate Access Blood Flow Up to 180 ml/min Return Replacement Up to 4500 ml/hr P. R. Dialysate I. S. up to 2500 ml/hr M. A. Replacement Patient Fluid Removal Up to 2000 ml/hr Effluent Fluid Composition: Dialysate Prismasate 5000mL Premixed Dialysate . Na+ = 140 mEq/L 5000mL. K+ = 0 mEq/L Na+ = 140 mEq/L. K = mEq/L. Cl- = mEq/L +. Cl = 117 mEq/L. Ca2+ = mEq/L - Ca Mg2+ = 1 mEq/L 2+ = mEq/L. Mg Lactate = 3 mEq/L 2+ = mEq/L. HCO3 = 32 mEq/L Lactate = 30 mEq/L. Glucose = 0 mg/dL Glucose = 100 mg/dL. Peripheral Electrolyte Replacement In the event of high volume Bicarbonate solutions, if Ca free: Peripheral CaCl2/MgSO4.

4 In the event of high clearance: prn Na phosphate Solutes: Azotemia Azotemia Increase Replacement fluid and/or dialysate flow rate Solutes: Sodium Hyponatremia Add 3% NaCl to dialysate @70 cc/5L bag Hypernatremia Increase peripheral IV D5W (1L) or 1/2 NS. Solutes: K. 1 L bag 5 L bag Serum Potassium Add 0 mEq / Liter None None > mEq / Liter Add 3 mEq / Liter mL mL > mEq /. Liter Add 4 mEq / Liter 10 mL 50 mL < mEq / Liter Hyperkalemia Zero K+, increase Replacement and/or dialysate flow rate Solutes: pH. Metabolic Acidosis NaHCO3 (50%) 100 cc over 1 hour IVSS, prn Change Replacement to D5W (1L) + 3 amps NaHCO3. Metabolic Alkalosis Change Replacement solution to NS + sliding scale KCl Solutes: Calcium z Hypercalcemia Change to HCO3 dialysate (Ca2+ free).

5 Increase HCO3 dialysate or Replacement flow rate z Hypocalcemia CaCl2 (10%) 10 cc/100 cc NS or D5W over one hour, prn Premixed calcium drip Solute: Mg and Phospate Hypomagnesemia MgSO4 (50%) 2 ml in 100 cc NS or D5W over one hour, prn Premixed magnesium drip Hypermagnesemia Same as Rx for hypercalcemia Hypophosphatemia Na Phosphate (3 mmol/ml) 5cc in 100cc NS IVSS over 2 hours, prn (repeat x 1 if PO4 < mg/dl). Hyperphosphatemia Same as Rx for hypercalcemia Anticoagulation Heparin 250 - 500 U/hr HIT: Argatroban - 1 mg/hr Bleeding risk: Citrate No anticoagulation Argatroban CRRT Anticoagulation Protocol 1. Call Hematology for approval. 2. In a 20 cc syringe (1000 mcg/mL): 30 microgram/kg/hr ( microgram/kg/min).

6 Rate: _____ microgram/hr = ____ mL / hr (Range 5 mL/hr). Use lower dose with liver failure. (15 mcg/kg/hr). Disconnect: Flush lumen with _____ mL of 1000 microgram/mL argatroban in each port (use internal volume as stated on catheter). Reconnection: Aspirate 5 mL from each port before re-connecting. 3. Write argatroban order separately. 4. Check PTT q 12 hours Citrate Regional Anticoagulation Cointault Nephrol Dial Transplant. 2004 Jan;19(1):171-8. CRRT in LVAD circuit CRRT. LVAD. CRRT- Controversial Issues HCO3- vs lactate solutions High vs standard delivered dose Convection vs diffusion Cost of CRRT vs HD. Does CRRT improve outcome (vs HD)? CRRT to prevent contrast nephropathy Lactate vs HCO3 Replacement N=117.

7 Open-label trial randomized to Replacement Fluid: HCO3. Lactate Kidney International 58 (4), 1751-1757. Effects of different doses of CVVH on outcomes of ARF. 425 patients with ARF. Patients were randomly assigned ultrafiltration at 20 mL/kg/h (Gr 1, n=146). 35 mL/kg/h (Gr 2, n=139). 45 mL/kg/h (Gr 3, n=140). Primary endpoint: survival at 15 days after stopping haemofiltration. Lancet. 2000 Jul 1;356(9223):26-30. Intensity of Renal Support in Critically Ill Patients with Acute Kidney Injury N Engl J Med. 2008 Jul 3;359(1):7-20. Diffusion vs. Convection 160. Diffusive transport Clearance (ml/min). 120 Convective transport 80. 40. 0 Urea, 60 D. 10 102 103 104 105 106. Creatinine, 113 D.

8 Molecular Weight Vit. B12, 1355 D. Inulin, 5200 D. Albumin, 55-60 kD. Cost of acute Renal failure requiring dialysis in the intensive care unit: clinical and resource implications of Renal recovery. Design Retrospective cohort study Patients with ARF needing dialysis April 1, 1996, - March 31, 1999. Setting: Two tertiary care intensive care units in Calgary, Canada. Patients: 261 critically ill patients. Outcomes: in-hospital and subsequent survival and Renal recovery The immediate and potential long-term costs Manns: Crit Care Med, 31(2). Impact of dialytic modality on mortality (HD vs CRRT). Am J Kidney Dis. 2002 Nov;40(5):875-85. Impact of dialytic modality on Renal recovery.

9 Efficacy and cardiovascular tolerability of extended dialysis in critically ill patients: A randomized controlled study Genius single-pass dialysis machine Kielstein J Kidney Dis. 2004 Feb;43(2):342-9. Clearances Hemodynamic Parameters MAP HR. CO SVR. The Prevention of Radiocontrast-Agent Induced Nephropathy by Hemofiltration CVVH 1000 ml/h, 4-8 hours pre and 18-24 hours after angiogram. N Engl J Med 2003; 349:1333-1340, Outcome: Renal Function Outcomes OUTCOME CONTROLS CVVH. 25% increase in 50% 5%. Serum Creatinine Renal Replacement : (Oliganuria 25% 3%. for >48 h despite 1 g IV furosemide). Mortality In hospital 14% 2%. One-year 30% 10%. Complications