When and how to start RRT in critically ill patients? Intensive Care Training Program Radboud University Medical Centre Nijmegen

When and how to start RRT in critically ill patients? Intensive Care Training Program Radboud University Medical Centre Nijmegen

Case history (1) 64 Hypertension 2004 AVR 2009 Paravalvular leak - dilated LV - PHT 2009 Redo AVR

Case history (2) 2010 Infected pacemaker pocket and leads 2010 Infected ICD pocket and leads 19/09 Prosthetic valve endocarditis with connection between aortic sinus and LA 23/09 Aortic valve and root replacement, mitral valve plasty, closure fistula, patch on LA

Creatinine 200 BUN 21.9 Lactate 2.4 Lactate 12.7 SvO2 81% Lactate 6.4 SvO2 72% MAP Milrinone NE Dobutamine/10 Epinephrine Vasopressin 0.04 E/min 80 OR CO 6.48 3.19 Methylene blue CO 7.29 3.54 CO 5.86 2.89 1,1 70 0,825 mm Hg 60 0,55 μg/kg/min 50 0,275 40 22/9-20.00 24/09 25/09 Diuresis 0-5 cc/hr 0 Creatinine 282 BUN 18.5 Potassium 2.9 ph 7.3 CVVH

Postoperative Day 1 ICU fellow raises two simple questions 1. Does early RRT improve outcome in this particular patient? 2. Would CVVH be helpful in stabilising hemodynamics?

28-D mortality (%) 40 30 20 10 0 Early RRT and outcome Start 7 hours 48.2 ml/kg/hr N = 106 - MV - Inotropic support P = 0.80 P = 0.25 8 Start 7 hours 20.1 ml/kg/hr Start 42 hours 19.0 ml/kg/hr Early HV Early LV Late LV N = 35 N = 35 N = 36 Median duration of RF in survivors (D) 6 4 2 0 Early HV Early LV Late LV > 50% of patients after cardiac surgery Bouman CS. Crit Care Med 2002;30:2205-2211

How should we explain this? Fluid Therapy Glomerulonephritis and other intrinsic disorders Systemic disorders (sepsis, rhabdomyolysis etc etc) AKI

Dogma Persistent renal ischemia and concentration of filtered toxins Prerenal failure Acute tubular necrosis Keep the patient well filled Most patients end up with a massively positive fluid balance

Renal blood flow Prowle JR. Blood Purif 2009;28:216-225

AKI

Glomerular hemodynamics

Decreased GFR in AKI

Encapsulated organs

Case history (3) Decision for early RRT (24/09) Mode CVVHDF - 25 ml/kg/hr (2000 cc) No anticoagulants ICU fellow raises simple question 1. Is there evidence that this RRT dose is to low?

Critically ill Age 18 Acute Kidney Injury CVVHDF Blood flow > 150 ml/min 40 ml/kg/hr 25 ml/kg/hr N = 721 N = 743 No differences in baseline characteristics 50 Low dose High dose Mortality (%) 40 30 20 10 0 44,7 44,7 36,9 38,5 90 D mortality 28 D mortality 0 46,2% 47,6% 1 35,4% 35,2% 2 14,7% 13,9% 3 3,4% 3,2% 4 0,4% 0,1% No. of nonrenal organ failures (%) No differences in need for RRT in survivors at day 28 and day 90 RENAL Replacement Therapy Study Investigators. N Engl J Med 2009;361:1627-1638

Case history (4) Diuresis (ml/day) 3000 2250 1500 750 25/09 vasopressin stop - rapid decrease NE Stop CVVH Start Furosemide 0 24/09 25/09 26/09 27/09 28/09 30/09 01/10 02/10 03/10 04/10 05/10 Discharge 11/10 - BUN 62.9, creatinine 252

Case history (5) After stopping CVVHDF creatinine increases > 250 μmol/l and urea increases > 60 mmol/l No bleeding diathesis or pericarditis ICU fellow raises simple question 1. Was this the right time to stop RRT?

When to stop RRT? Relative paucity of data about the process of discontinuation of RRT No standardised criteria Risk factors for resuming RRT after stopping > 50% cardiovascular surgery Wu VC. Intensive Care Med 2008;34:101-108

When to stop RRT? ROC 0.880 Non-oliguria Oliguria Wu VC. Intensive Care Med 2008;34:101-108

Case history (6) Risk factors - high SOFA score, prolonged dialysis duration, oliguria Despite these risk factors - no redialysis 11/10 transfer to MC Readmission ICU for sputum stasis - tracheostomy Prolonged but uncomplicated course

Questions 1. What is the ideal timing for starting RRT in patients with MODS? 2. Does CVVH improve hemodynamic stability? 3. What is the optimal RRT dose in patients with MODS? 4. What is the optimal timing for stopping RRT in patients with MODS?

N = 618 AKI - fluid overload and survival Bouchard J. Kidney International 2009;76:422-427

Renal recovery and fluid overload Fluid overload No fluid overload Cpmplete renal recovery (%) 60 45 30 15 0 P = 0.24 At time of AKI diagnosis P < 0.001 At time of peak serum creatinine Bouchard J. Kidney International 2009;76:422-427

Discussion

Discussion RRT started late is associated with longer duration of RRT RRT started late is associated with a longer hospital stay RRT started late is associated with reduced renal recovery Temporal delay in RRT after ICU admission is associated with increased hospital death

Bagshaw SM. Crit Care 2009;13:317

RCT of hemofiltration in septic shock 35 ml/kg/hr 65 ml/kg/hr Boussekey N. Intensive Care Med 2008;34:1646-1653

Boussekey N. Intensive Care Med 2008;34:1646-1653

RRT dose Total 3490 patients No evidence that high dose RRT improves survival No differences in renal recovery, ICU LOS and adverse effects Zhang Zhonghen. J Crit Care 2010

High-dose RRT Survival Dose dependent region Inflection point Dose independent region Hypotension Electrolyte disorders Micro-nutrient depletion Hypothermia Changes in acid-base status Error in drugs RRT dose Schiffl H. Int Urol Nephrol 2010;42:435-440

When do physicians stop RRT? BEST Kidney study 1006 patients needing CRRT 529 survived 313 successfully weaned 216 needed redialysis Uchino S. Crit Care Med 2009;37:2576-2582

At the time of stopping CRRT

Successful discontinuation

The effect of diuretics Diuretics (-) 436 ml Diuretics (+) 2330 ml 80% change of successful weaning if: Diuresis > 400 ml/day without diuretics or > 2300 ml/day with diuretics Uchino S. Crit Care Med 2009;37:2576-2582