{"id":5122,"date":"2011-07-14T20:23:39","date_gmt":"2011-07-14T20:23:39","guid":{"rendered":"http:\/\/crashtext.org\/misc\/5122.htm\/"},"modified":"2013-12-01T12:34:10","modified_gmt":"2013-12-01T17:34:10","slug":"renal-failure","status":"publish","type":"post","link":"https:\/\/crashingpatient.com\/medical-surgical\/renal\/renal-failure.htm\/","title":{"rendered":"Renal Failure"},"content":{"rendered":"

FeNa and FeUrea<\/a><\/p>\n

<\/span>Risk, Injury, Failure, Loss, End-Stage Renal Disease (RIFLE) Classification for the Definition of ARF<\/span><\/h2>\n

GFR Criteria Urine Output Criteria Risk Serum creatinine level increased 1.5 times or decrease in GFR of > 25% < 0.5 mL\/kg\/h for 6 h Injury Serum creatinine level increased 2.0 times or GFR decreased by > 50% < 0.5 mL\/kg\/h for 12 h \u00a0 Failure Serum creatinine level increased 3.0 times, GFR decreased by > 75%, or serum creatinine level decreased by > 4 mg\/dL < 0.3 mL\/kg\/h for 24 h or anuria for 12 h Loss Persistent acute renal failure, complete loss of kidney function for > 4 wk \u00a0 End-stage renal disease End-stage renal disease for > 3 mo<\/p>\n

* From Bellomo et al.12 GFR = glomerular filtration rate. The classification system includes separate criteria for creatinine and urine output. The criteria that lead to the worst possible classification should be used.<\/p>\n

Go to source>><\/p>\n

\"\"<\/a><\/h4>\n

<\/span>Urea Cycle<\/span><\/h2>\n

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<\/span>UA<\/span><\/h2>\n

Heme-detects free Hb better than RBCs<\/p>\n

Protein-doesn\u0092t pick up Bence-Jone\u0092s<\/p>\n

Casts-hyaline in dehydration, red is glomerulus, white is parenchymal<\/p>\n

Proteinuria->3.5 g\/24 hrs=nephrosis (glomerular process), also c edema and Hypercoaguable state<\/p>\n

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Minimum urinary output in adults is 0.5 cc\/kg\/hour, in kiddies 1 cc<\/p>\n

Table 1: Evaluation Of Oliguria (Neligan)<\/b><\/p>\n

Pre-Renal<\/b> Renal (ATN)<\/b> Post-Renal<\/b> Specific Gravity >1.02 1.012 1.012 Urine Osm >400 300 \u00b1 20 300 \u00b1 40<\/p>\n

U:P Osmolality<\/p>\n

>1.5<\/p>\n

1<\/p>\n

1<\/p>\n

U:P Creatinine<\/p>\n

>40<\/p>\n

<20<\/p>\n

<20<\/p>\n

Urine Na (mEq\/L)<\/p>\n

<20<\/p>\n

>30<\/p>\n

<30<\/p>\n

FENa (%)<\/p>\n

<1<\/p>\n

>3<\/p>\n

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RFI %<\/p>\n

<1%<\/p>\n

>1%<\/p>\n

<1%<\/p>\n

CCR (mL\/min)<\/p>\n

15-20<\/p>\n

<10<\/p>\n

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BUN\/Cr<\/p>\n

>20<\/p>\n

<10<\/p>\n

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ATN = acute tubular necrosis; CCR = creatinine clearance; FENa = fractional excretion of sodium; Na = sodium; U:P = urine:plasma. RFI = Renal Failure Index, calculated as Urinary Sodium \/ (Urinary Creatinine \/ Serum Creatinine)<\/p>\n

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Anuria is postrenal obstruction until proven otherwise. Consider abdominal compartment syndrome<\/p>\n

<\/span>Acute Renal Failure (ARF)<\/span><\/h2>\n

Get CBC, Lytes, Ca, Phos, Albumin, Mg.\u00a0 UA, U Lytes, U creatinine, If new, get renal UTS.<\/p>\n

creatinine is from creatine breakdown; without GFR, it increases 1-2 mg\/dl\/day<\/p>\n

<\/span>Prerenal<\/span><\/h3>\n

Azotemia<\/p>\n

caused by extracellular fluid loss \/ sequestration or impaired cardiac function<\/p>\n

afferent arteriolar constriction<\/p>\n

Can result in ATN<\/p>\n

prostoglandins allow renal vasculature dilation so can also result from NSAIDs<\/p>\n

ACEIs can also cause this state as they reduce perfusion pressure and allow dilation of efferent arteriole<\/p>\n

FENa = (UNa \/ PlasmaNa) \/ (U creatnine \/ Plasma creatnine) x 100<\/p>\n

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UNa<30, FENa<1.0% with normal UA or scant hyaline casts in urine<\/p>\n

<\/span>Intrarenal Azotemia<\/span><\/h3>\n

Glomerular-red cell casts are diagnostic, proteinuria, hematuria<\/p>\n

Interstitial-drugs (PCN, ASA) or infection, pyuria, WBC casts, eosinophils<\/p>\n

Vascular-glomerular perfusion is interrupted by processes such as thrombosis, hypertension, HUS, TTP, and vasculitis<\/p>\n

ATN<\/h4>\n

ischemia:\u00a0 prolonged prerenal<\/p>\n

nephrotoxins:\u00a0 aminoglycosides, , contrast media (Always hydrate before, can also give lasix+benadryl).<\/p>\n

pigmenturia:\u00a0 rhabdomyolysis<\/p>\n

UNa>30, FENa>1%<\/p>\n

 <\/p>\n

pigmented granular casts, renal tubular epithelial cells, granular casts<\/p>\n

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If oliguric, has a higher mortality.\u00a0\u00a0 Other organs effected:\u00a0 can give pericardial effusion, Qualitative PLT defect.<\/p>\n

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<\/span>Postrenal Azotemia<\/span><\/h3>\n

<\/span>Renal Replacement Therapy (HD)<\/span><\/h3>\n

consider when BUN>100-120 and\/or creatinine>10<\/p>\n

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(Inten Care Med 2001;27:1685)<\/p>\n

GFR is all that matters<\/p>\n

 <\/p>\n

Normal UO>800 cc\/24 hrs<\/p>\n

ARI Cr>1.4, Bun>22, <800 cc\/24 hours or <200\/6<\/p>\n

ARF Cr>2.8, Bun>44, <400\/24 or <100\/6<\/p>\n

Severe is ARF that requires RRT<\/p>\n

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<\/span>Chronic Renal Failure<\/span><\/h2>\n

Cockcroft and Gault Creatinine Clearance=(((140-age) x Kg) \/ 72 x serum Cr), multiply by 0.85 if female or fat<\/p>\n

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Diabetes, HTN, HIV, Glomerular<\/p>\n

Uremia, dementia, restless legs syndrome, anemia<\/p>\n

Emergent Dialysis-APE, Severe HTN, HyperK, Acidemia, Pericarditis<\/p>\n

Dialysis Complications-call surg immediately if shunt thrill is not present<\/p>\n

Use dDAVP to reverse qualitative plt defect.<\/p>\n

CAPD (peritoneal dialysis)->100 WBC=SBP, Remove cath if fungal.<\/p>\n

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Management<\/h4>\n

Tight blood pressure control to maintain renal perfusion (MAP 90-140)<\/p>\n

Sodium balance as damaged kidneys can not retain sodium as well as healthy<\/p>\n

Free water balance<\/p>\n

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<\/span>Hemodialysis Emergencies<\/span><\/h2>\n

Access Emergencies<\/p>\n

How to tell fistula from graft<\/p>\n

Fistula 1 scar soft to touch<\/p>\n

Graft 2 scars feels artificial\/hard to touch<\/p>\n

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Potential Causes of Intradialytic Hypotension (IDH)<\/p>\n

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