Presentation on theme: "ACUTE RENAL FAILURE IN PREGNANCY"— Presentation transcript:
1ACUTE RENAL FAILURE IN PREGNANCY Dr. Mona Shroff, M.D.(O&G)Asst.Prof;SMIMER; SURATEMOC Advanced Trainer (FOGSI,GOI,JHPIEGO EmOC project)Diploma in O & G Ultrasound (Ian Donald)
2This presentation covers BASIC OUTLINEInvestigationsMANAGEMENT PRINCIPLESPrerenal Vs ATN Vs ACNROLE OFNutritionVolume & metabolic controlDiuretics : helpful or harmful ??Dopamine : helpful or harmful ??Dialysis : when & which ??Renal biopsy ??DeliveryConditions specific to pregnancy
3DEFINITIONS OF ARFThe syndrome is characterised by a sudden in parenchymal function (UOP<400ml/d;30ml/hr) which is usually but not always reversibleThis produces disturbance of water, electrolyte, acid base balance and nitrogenous waste products & blood pressure.
4Physiological changes in normal gestation Kidney weight and size increaseDilation of renal calyces, pelves, and uretersUrinary stasisGlomerular filtration, effective renal plasma flow, fractional clearance of urate increaseBicarbonate reabsorption threshold decreases
5Clinical relevanceConcentrations of serum creatinine, urea N, and uric acid of 0.9, 14, and 5.6 mg/dl, normal in nonpregnant subjects, are already suspiciously high in gravid women.Asymptomatic bacteriuria - frank pyelonephritis.PP reduction in size should not be mistaken for parenchymal lossPost renal failure difficult to diagnoseS.bicarb lower,PCO2 10 mmHg lower
6CausesBimodal distribution -peaks in the first trimester (related to unregulated and/or septic abortion,hyperemesis) and the late third trimester (related to obstetric complications APH,PPH,Preeclampsia, Chorioamnionitis,AFE etc).
9Loss (L) - Persistent ARF, complete loss of kidney function >4 wk The RIFLE classification (ADQI group) of ARF:Risk (R) - Increase in serum creatinine level X 1.5 or decrease in GFR by 25%, or UO <0.5 mL/kg/h for 6 hoursInjury (I) - Increase in serum creatinine level X 2.0 or decrease in GFR by 50%, or UO <0.5 mL/kg/h for 12 hoursFailure (F) - Increase in serum creatinine level X 3.0, decrease in GFR by 75%, or serum creatinine level > 4 mg/dL; UO <0.3 mL/kg/h for 24 hours, or anuria for 12 hoursLoss (L) - Persistent ARF, complete loss of kidney function >4 wkEnd-stage kidney disease (E) - Loss of kidney function >3 months
12Management Restore or maintain fluid balance The maintenance of electrolytes and acid base balanceThe maintenance of nutritional supportPrevention of infectionAvoid renal toxins (including NSAIDS)Instigate renal replacement therapies
13Prerenal failure Adequately replace blood & fluid losses,maintain BP. Control continuing blood lossMannitol (100ml, 25%) trial to d/d b/w reversible prerenal failure & established ATN (provided oliguria <48 hrs & U:P osmolality > 1.05)If diuresis (>50ml/hr or doubling) established within 3 hrs,maintain NS infusion acc to UOP & replace electrolytes acc to urinary loss estimations.If unsuccessful –objective is to support the functionally anephric pt till kidneys recover.
14Volume control IP/OP charting daily State of hydration-wt,hct,protein Input = Output/24hrs + 500ml(nonfebrile)+ 200 ml/ deg C of inc. in TemBalance : kg wt loss/dAvoid overhydration : Rx diuretics,dialysisCVP monitoring (b/w 10-15cm H2O)
15DiureticsDiuretics commonly have been given in an attempt to convert the oliguric state to a nonoliguric state. However, diuretics have not been shown to be beneficial, and they may worsen outcomes.In the absence of compelling contradictory data from a randomized, blinded clinical trial, the widespread use of diuretics in critically ill patients with acute renal failure should be discouraged.Useful only in management of fluid-overloaded patientsCantarovich F, Rangoonwala B, Lorenz H, Verho M, Esnault VL. High-dose furosemide for established ARF: a prospective, randomized, double-blind, placebo-controlled, multicenter trial. Am J Kidney Dis 2004;44:402-9.Kellum JA. Systematic review: The use of diuretics and dopamine in acute renal failure: a systematic review of the evidence. Critical Care1997;1(2):53–9.
16DOPAMINEDopamine traditionally has been used to promote renal perfusion(1-5 mcg/kg/min )However, systematic reviews of dopamine treatment in critically ill patients and in patients with sepsis do not support the use of dopamine to prevent renal insufficiency, morbidity, or mortality. In the majority of ARF studies, dopamine was associated only with an increase in urine output.Kellum JA, Decker MJ. Use of dopamine in acute renal failure: a meta-analysis. Crit Care Med 2001;29:Denton MD, Chertow GM, Brady HR. "Renal-dose" dopamine for the treatment of acute renal failure: scientific rationale, experimental studies and clinical trials. Kidney Int 1996;50:4-14.
17NutritionINTAKE 1500 cal (protein free) Oral/parenteral If vol limitation-50%D via central vein Essential L-aminoacids: K,Mg,P:Improve wound healing, hasten recovery Protein intake of 0.6 g per kg per day
18Electrolyte & acid-base correction Hyperkalemia, which can be life-threatening, should be treated bydecreasing the intake of potassium,delaying the absorption of potassium,exchanging potassium across the gut lumen using potassium-binding resins,controlling intracellular shiftsdialysis.Acidosis- sodabicarb ,dialysis
19Treat coagulopathy with FFP for a prolonged aPTT, cryoprecipitate for a fibrinogen level less than 100 mg/dL, and transfuse platelets for platelet counts less than 20,000/mm3Timely identification of UTI, proper treatment & prevention using prophylactic antibiotics
20Indications for Kidney Replacement Therapy Acidosis unresponsive to medical therapyAcute, severe, refractory electrolyte changes (e.g., hyperkalemia)EncephalopathySignificant azotemia (blood urea nitrogen level >100 mg per dL [36 mmol per L])Significant bleedingUremic pericarditisVolume overload
21Early “Prophylactic” Dialysis Allows more liberal fluid, protein & salt intake.Prevent hyperkalemic emergencies.infectious Cx.Improves comfort & survival
22Hemodialysis Vs Peritoneal dialysis Limited usefulness if hypotensionC/I in actively bleeding pt.Controlled anticoagulation reqdVolume shifts-carefulFaster correctionCan be used in preg/PP pt.Easily availableSimple,inexpensiveLower Cx rateMinimises rapid metabolic pertubations & fluid shiftsInsert cath high direct vision
23DeliveryDevelopment of ARF in obs pt is indication of delivery in majority cases.Deliver if UOP<20 ml/>2hrs despite adequate vol expansion & immediate delivery not expectedRedistribution of CO – better renal perfusion.Remove fetus from hostile environment.Neonate urea –osmotis diuresis -dehydration
24Renal biopsy Potentially v.risky in pregnancy Defer until postpartum even if ACN( for prognostication).Rare indication sudden renal failure before 32 wks with no obvious cause.
25PreeclampsiaA decrease in the GFR occurs secondary to intrarenal vasospasm. This may manifest as a "prerenal" picture. Acute renal failure (ARF) may develop, and acute tubular necrosis (ATN) may ensue if this hypoperfusion persists.
26Pre-eclampsia: Management Renal problems Hyperuricaemia and proteinuria are NOT indications for delivery per seConsider delivery for progressive renal impairment (creatinine >0.09 mmol/L)Care with fluids (pulmonary oedema can kill!)Kidney Function is Critical for Drug Elimination
27Pre-eclampsia Invasive monitoring CVP monitoring may NOT be helpful!poor correlation between CVP and PCWPPA catheters have risks!rare indications:pulmonary oedema resistant to diureticsoliguric renal failure despite volume expansion
28Idiopathic postpartum renal failure Associated primarily with microangiopathic processesPostpartum hemolytic-uremic syndrome.These were often irreversible and were associated with substantial mortality.Now improved outcome with plasma exchange,dialysis,prostacyclin infusion, correcting coagulopathy
29ACUTE FATTY LIVER OF PREGNANCY Associated with acute renal failure in up to 60 percent of cases.The diagnosis should be suspected in a woman with preeclampsia who has jaundice,hypoglycemia, hypofibrinogenemia, and a prolonged PTT in the absence of abruptio placentae.
30KEY RECOMMENDATIONS FOR PRACTICE Identify & prevent at prerenal phase as early as possibleDopamine should not be used to preventacute renal failure. (Evidence level A)Diuretics should not be used to treat oliguria in patients with acute renal failure unless volume overload (Evidence level B)Early prophylactic dialysis should be strongly considered.The maintenance of electrolytes,acid base balance & nutritional support plays vital role.