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 Continuous Ultra Filtration P R I S M A Maximum Patient Fluid Removal Rate = 2000 ml/hr Effluent
Therapy Options Access CVVH Continuous Veno-Venous HemoFiltration P R I S M A Return Replacement Maximum Patient Fluid Removal Rate = 1000 ml/hr Effluent
Therapy Options Access Dialysate Return CVVHD Continuous Veno-Venous HemoDialysis P R I S M A Maximum Patient Fluid Removal Rate = 1000 ml/hr Effluent
Therapy Options Access Dialysate Return CVVHDF Continuous Veno-Venous HemoDiafiltration P R I S M A Replacement Maximum Pt. fluid removal rate = 1000 ml/hr Effluent
A Case 35 year old female is s/p OHT, POD#1. Remains intubated, MAP 65 on Levo 20, Pit 3, Milrinone 0.25 Urine output 10 ml.hour (Intake 150ml/h) PAD 20 FiO2 0.60- ABG 7.45/35/102 BMP 132/4.6/103/18/25/1.3 (Baseline 1.0)
Indications for Renal Replacement Standard indications Volume overload Hyperkalemia Metabolic Acidosis Uremic Platelet Dysfunction Uremic Encephalopathy
Modality Selection Volume only SCUF Solutes +/- Volume CVVH CVVHD CVVHDF Hypercatabolic +/- Volume CVVHDF
Prescription Variables Dialysate Blood Flow Up to 180 ml/min Access Return Replacement Up to 4500 ml/hr Dialysate up to 2500 ml/hr Patient Fluid Removal Up to 2000 ml/hr P R I S M A Replacement Effluent
Fluid Composition: Dialysate Prismasate 5000mL Na + = 140 meq/l K + = 0 meq/l Cl - = 109.5 meq/l Ca 2+ = 3.5 meq/l Mg 2+ = 1 meq/l Lactate = 3 meq/l HCO 3 = 32 meq/l Glucose = 0 mg/dl Premixed Dialysate 5000mL Na + = 140 meq/l K + = 2.0 meq/l Cl - = 117 meq/l Ca 2+ = 3.5 meq/l Mg 2+ = 1.5 meq/l Lactate = 30 meq/l Glucose = 100 mg/dl
Peripheral Electrolyte Replacement In the event of high volume Bicarbonate solutions, if Ca free: Peripheral CaCl 2 /MgSO 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 D 5 W (1L) or 1/2 NS
Solutes: K 1 L bag 5 L bag Serum Potassium Add 0 meq / Liter None None > 5.5 meq / Liter Add 3 meq / Liter 7.5 ml 37.5 ml > 4.5 5.5 meq / Liter Add 4 meq / Liter 10 ml 50 ml < 4.5 meq / Liter Hyperkalemia Zero K +, increase replacement and/or dialysate flow rate
Solutes: ph Metabolic Acidosis NaHCO 3 (50%) 100 cc over 1 hour IVSS, prn Change replacement to D 5 W (1L) + 3 amps NaHCO 3 Metabolic Alkalosis Change replacement solution to NS + sliding scale KCl
Solutes: Calcium Hypercalcemia Change to HCO 3 dialysate (Ca 2+ free) Increase HCO 3 dialysate or replacement flow rate Hypocalcemia CaCl 2 (10%) 10 cc/100 cc NS or D 5 W over one hour, prn Premixed calcium drip
Solute: Mg and Phospate Hypomagnesemia MgSO 4 (50%) 2 ml in 100 cc NS or D 5 W 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 PO 4 <1.0 mg/dl) Hyperphosphatemia Same as Rx for hypercalcemia
Anticoagulation Heparin 250-500 U/hr HIT: Argatroban 0.5-1 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 (0.5 microgram/kg/min) Rate: microgram/hr = ml / hr (Range 0.5 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 O.. Nephrol Dial Transplant. 2004 Jan;19(1):171-8.
CRRT in LVAD circuit CRRT LVAD
CRRT- Controversial Issues HCO - 3 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 HCO 3 Replacement N=117 Open-label trial randomized to Replacement Fluid: HCO 3 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 Clearance (ml/min) 160 120 80 40 Diffusive transport Convective transport 0 10 10 2 10 3 10 4 10 5 10 6 Urea, 60 D Creatinine, 113 D Molecular Weight Vit. B 12, 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). 2003.449-455
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.
Efficacy and cardiovascular tolerability of extended dialysis in critically ill patients: A randomized controlled study Genius single-pass dialysis machine Kielstein JT..Am 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 Serum Creatinine Renal replacement: (Oliganuria for >48 h despite 1 g IV furosemide) 50% 5% 25% 3% Mortality In hospital One-year 14% 30% 2% 10%
Complications