Lecture 10 - Glomerular Disease --------------------------
Lecture 10 - Glomerular Disease --------------------------
Where do transitional cells come from?
Bladder
In a male patient that presents with increased frequency of urination you will want to rule out
Prostate cancer and BPH
What will be included in your work up for a patient that will present with dysuria?
Genital and rectal examUA, urine culture, urine cytologyBUN/CrRenal USCT abdomen/pelvisCystoscopyPSA
What type of protein is tested on urine dipstick?
Albumin
What does WBC in the urine mean?
Renal parenchymal inflammation/infection
What will nitrites in the urine suggest?
Gram negative rod infection
What patient population will you always treat for a bacterial UTI without the presence of white blood cells on urinalysis
Pregnant patients
What are the different types of casts in the urine on urinalysis
RBC, WBC, Granular, Tubular, Hyaline, Waxy/Broad
What crystals could you have present on the microscopic exam of urinalysi
Calcium oxalate monohydrate, calcium oxalate dehydrate, uric acid, cysteine, struvite
T/f if you have a high specific gravity on urine dipstick this will correlate with heavy proteinuria
False
What is normal specific gravity of urine
1.003 - 1.030
What is a physiological cause of blood and heavy proteinuria in a urinanalysis
Heavy exercise
What diagnostic test is the best to be order in a patient that you suspect is a renal stone
CT scan
What would be the cause of Waxy/broad looking casts?
Chronic renal failure, dialysis use
What would be the value for microalbuminuria?
30 - 300 mg/24 hours
What does a spot urine test?
Protein/creatinine ratio
What is the underlying problem with a patient that has glomerular disease?
Filtering substances back into blood stream (losing them in the urine)
What is the underlying problem with Tubular disease?
Problems with Resorption/secretion
Abnormal glomerular podocyte permeability to protein
Nephrotic syndrome
Intraglomerular inflammation
Glomerulonephritis
What does a patient with Glomerulonephritis present with?
Sudden onset of hematuria, proteinuria, and dysmorphic RBCs or RBC casts
What will a patient that has nephrotic syndrome present with?
Hyperproteinuria (>3.5 g/24 hrs)Hypoproteinemia (albumin < 3.5 g/dL)HyperlipidemiaEdema (include periorbital)
What is the most common cause of nephrotic syndrome
DM and HTN
Why do patients with nephrotic syndrome also have a prothrombotic state?
Urinary losses of protein C, protein S and antithrombin
What is the best initial test to diagnosis nephrotic syndrome
Urinalysis
What may you see on urinalysis of a patient with nephrotic syndrome?
Maltese crosses (oval fat bodies)
After a urinalysis what will you want to perform on a patient with nephrotic syndrome
Protein/creatinine ratio
What is the most accurate test to diagnose nephrotic syndrome
Biopsy
What is the treatment for a patient with nephrotic syndrome
Prednisone x 12 weeks. Add cyclophosphamide if no response. ACEI for protein loss. Statins
Spike and dome subepithelial deposits
Membranous Nephropathy
Subendothelial deposits that result in nephrotic syndrome
Membranoproliferative
What are some causes of membranoproliferative nephrotic syndrome
Immune complex mediated, infection (HCV, HBV), SLE, cryoglobuliemia, Sjogren's, lymphomas, dysproteinemia, idiopathic
What is the most common cause of nephrotic syndrome
Focal segmental
What are the causes of focal segmental nephrotic syndrome
HIV, NSAIDs, lymphomas, IV heroin, pamidronate, congenital, obesity, anabolic steroids
NSAIDs can cause what different types of nephrotic syndrome?
Minimal change disease, Membranous, Focal segmental
On light microscopy will you be able to tell pathology of minimal change disease
No
What will you see on electron microscopy of a patient with minimal change disease?
Widespread fusion of epithelial cell foot processes
What will you see on light microscopy of membranous nephropathy
Diffuse thickening of the glomerular basement membrane with essentially normal cellularity (subepithelial deposits)
Where are the subepithelial deposits at in the glomerulus of a patient with membranous nephropathy
Basement membrane
What will you see on light microscopy of a patient with focal segmental glomerulosclerosis?
Moderately large segmental area of sclerosis with capillary collapse
What is the most likely pathology of a patient with diabetes mellitus that also has nephrotic syndrome
Nodular glomerulosclerosis (kimmelsteil wilson)
What pathologies will cause larger kidneys?
Diabetes mellitus, amyloidosis, polycystic kidney disease, hydronephrosis, HIV
What systemic disease could be the cause of nephrotic syndrome?
Diabetes mellitusAmyloidosis SLECryoglobulinemia
What will you see of a kidney biopsy in a patient with amyloidosis?
Apple green birefringence with Congo red stain
On electron microscopy you see subepithelial deposits and intraendothelial tubuloreticular inclusions resulting in hyperproteinuria; what is the most likely systemic disease causing this nephrotic syndrome
SLE
What type of nephrotic syndrome will SLE present with
Membranous GN to glomerulosclerosis
What is the treatment for a patient with SLE and membranous glomerulonephropathy
Steroids, mycophenolate mofetil, cyclophosphamide
How do you treat hemorrhagic cystitis
Mensa
What are the different types of glomerulonephropathy in patients with lupus?
Class I - minimal mesangial lupusClass II - Mesangial proliferative LGNClass III - Focal LGN (<50% glomeruli) Class IV - diffuse LGN (>50%) Class V - Membranous LGNClass VI - Advanced sclerotic LGN (>90% sclerotic glomeruli)
What will be present with nephritic syndrome?
HypertensionHematuriaOliguriaAzotemia
Coca Cola colored urine, occurs in 1-3 weeks, periorbital edema, HTN, oliguria
Post infectious glomerulonephritis
What is the best initial test for a patient that presents with Coca Cola colored urine
Urinalysis
What would be the next best test for diagnosis of post infectious glomerulonephritis?
ASO and anti-DNAse Ab titer
T/f management of strep infection will reverse GN
False
What would be the treatment for a patient that has post infectious glomerulonephritis?
Antibiotics, diuretics if hypervolemic
What will the subepithelial deposits look like on electron microscopy of a patient with postinfectious glomulonephritis?
Hump-shaped appearance (there will also be hematuria and neutrophils attached to the denuded GBM)
What is the most common cause of acute glomerulonephritis in the US?
IgA nephropathy (Berger disease)
What is IgA nephropathy associated with?
RA, HIV, Celiac disease, AS, Reactive arthritis and liver failure
What is the most accurate test for diagnosing berger's disease?
Kidney biopsy
What are the different types of membranoproliferative
Type 1 - tram trackType 2 - ribbon like
How can you tell the difference between membranoproliferative and fibrillary - immunotactoid glomerulonephritis
Membranoproliferative will have a decreased complement C3Fibrillary and Immunotactoid - will have normal C 3
Anti-GBM glomerulonephritis is also called
Goodpastures syndrome
What are the characteristics of Anti-GBM glomerulonephritis
GN and pulmonary hemorrhage
What is the best initial test for Anti-GBM Glomerulonephritis
Antiglomerular basement membrane antibodies
What is the treatment for goodpastures syndrome
Plasmapheresis, steroids, cyclophosphamide
Renal and pulmonary disease + c-ANCA/anti PR3 in 90%
Wegener's (granulomatosis with polyangiitis)
Renal and pulmonary disease (mostly) + asthma + p-ANCA/anti MPO in 50%
Chung Strauss (eosinophilia granulomatosis with polyangiitis
How do you diagnose polyarteritis nodosa
Angiography of renal (or mesenteric or hepatic) arteries shows aneurysmal dilation
What is the most accurate test for polyarteritis nodosa
Biopsy of symptomatic site
What is the treatment for polyarteritis nodosa
Prednisone, then cyclophosphamide
Congenital defect of type 4 collagen
Alpert syndrome
Glomerular disease with sensorineural hearing loss and visual disturbances
Alport syndrome
What will you find on a skin biopsy of a patient with Alport syndrome
Alpha 5 antibodies
Lecture 7 - AKI & CKD -------------------------------------
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what is the general problem with a patient that has pre-renal AKI
kidneys are not getting enough blood
which kidney will most likely be given to a donor
left kidney because the left renal vein is longer
What would be considered acute kidney injury (AKI)
urine output < 0.5 ml/kg/hr for > 6 hours or abrupt increase in creatinine > 0.03 mg/dl (occurs in less than 48 hours) ORincrease in creatinine > 50%
ACUTE KIDNEY INJURY (AKI) =• Urine output <______ mll* /kg/hr for > 6 hrs or abrupt increase in creatinine > 0.03 mg/dl (occurs in less than 48 hours) OR•Increase in creatinine > 50%
0.5
what are the most common findings on physical exam for a patient with acute kidney injury (AKI)
weight gain and edema
what are emergency scenarios of a patient with acute kidney injury?
hyperkalemia, metabolic acidosis, percarditis, fluid overload, encephalopathy
increased BUN and creatinine
azotemia
What is the AKI Rifle Criteria?
Risk - GFR decrease by 25% (1.5 fold increase in creatinine)Injury - GFR decrease by 50% (2 fold increase in creatinine) Failure - GFR decrease by 75% (3 fold increase in creatinine) Loss - complete loss of kidney function requiring dialysis for > 4 weeksESRD - complete loss of kidney function requiring dialysis for > 3 months
what is the most common cause of death in patients with AKI
infection
what would be the diagnostic approach to a patient with AKI
1) history and physical 2) Determine the duration (look for a baseline creatinine) 3) determine pre-renal, intrarenal or postrenal4) Medication review5) Labs and imaging
What will you want to monitor in a patient with AKI?
daily weights (best way)ins and outsBP serum electrolytesHg and Hctsigns of infection
What are the most important causes of prerenal AKI for a podiatrist to know?
SepsisDehydrated (elderly)CHF (decreased cardiac output)NSAIDsRenal artery stenosis(ANYTHING that decreases perfusion can cause AKI. There's nothing wrong with the kidney...yet)
what are the causes of prerenal AKI
hypotension: anaphylaxis, sepsis, blood loss, dehydrationHypoolemia: burns, diuretics, pancreatitis, CHF (decreased CO), hypoalbuminemia, cirrhosisrenal artery stenosis, vasculitis
what medications could cause prerenal AKI
NSAIDs, ACE inhibitors, IV contrast, hypercalcemia, calcineurin inhibitors
what labs would be significant for Prerenal AKI
BUN/Cr: >20:1Urine Na: <20 mEq/LFractional excretion of Na: < 1% Urine osmolarity > 500 mOsm/kg
(**) What type of casts will you see with prerenal AKI
transparent hyaline casts (Tamm Horsfall proteins)
Tamm Horsfall proteins are found in
prerenal AKI
(**) what are the treatment options of prerenal AKI
(correct the cause)IV NS (not to volume overloaded patients).
what medications will you want to stop in pre-renal AKI
ACE inhibitors, metformin, NSAIDs
A 67 YO DIABETIC MALE PRESENTS WITH A MALODOROUS FOOT ULCER. HE IS TAKING LISINOPRIL FOR HTN, METFORMIN FOR DIABETES AND AN NSAID FOR PAIN. HIS HR 100, T 100.7F, RR 22. PHYSICAL EXAM REVEALS DRY MOUTH, SKIN TENTING. BUN = 80, CR = 3. TRANSPARENT HYALINE CASTS ARE FOUND IN HIS URINE.WHAT'S YOUR DIAGNOSIS?•A. Sepsis with prerenal AKI•B. Sepsis with acute tubular necrosis•C. Sepsis with allergic interstitial nephritis•D. Sepsis with postrenalAKI•E. Sepsis with rhambodmyolysis
•A. Sepsis with prerenal AKI(PRErenal = sepsis, dehydration, CHF, Renal Artery Stenosis, NSAIDs, BUN/Cr > 20:1, Hyaline casts)
A 67 YO DIABETIC MALE PRESENTS WITH A MALODOROUS FOOT ULCER. HE IS TAKING LISINOPRIL FOR HTN, METFORMIN FOR DIABETES AND AN NSAID FOR PAIN. HIS HR 100, T 100.7F, RR 22. PHYSICAL EXAM REVEALS DRY MOUTH, SKIN TENTING. BUN = 80, CR = 3. TRANSPARENT HYALINE CASTS ARE FOUND IN HIS URINE.You diagnose Sepsis with prerenal AKI, how do you treat this patient?
IV Normal Saline Stop meds like ACEI, Metformin, NSAIDs
(**) INTRINSIC RENAL INJURY: - Acute Tubular Necrosis (ATN)What is the most common cause of ATN?
prolonged ischemia (progression of prerenal disease/ hypoperfusion)
(**) what type of casts would you see with Acute Tubular Necrosis
Pigmented granular muddy brown casts
How long does it take for DRUG-induced ATN to occur?
5 to 10 days
what are the causes that could cause ATN?
NSAIDs, aminoglycosides, amphotericin, cisplatin, cyclosporine, hemoglobin, myoglobin, Ig Light chains, Uric acid crystals
What is the treatment for ATN
stop toxin exposure and hydration
what are the lab values of a patient that would have intrinsic renal injury like ATN?
BUN/Cr ratio: 10:1 Urine Na > 20 mEq/LFractional Excretion of Na > 1%Urine Osmolality < 300 mOsm
A 67 YO MALE PRESENTS WITH A MALODOROUS FOOT ULCER. HR 100, T 100.7F, RR 22. PE REVEALS DRY MOUTH, SKIN TENTING. BUN = 60, CR = 5. WHAT'S YOUR DIAGNOSIS?•A. Sepsis with prerenal AKI•B. Sepsis with acute tubular necrosis•C. Sepsis with allergic interstitial nephritis•D. Sepsis with postrenalAKI•E. Sepsis with rhambodmyolysis
•B. Sepsis with acute tubular necrosis(BUN/Cr is 60:5)
what are the risk factors for constast induced AKI
DM, CKD, CHF, Hypotension, increased contrast volume
Contast induced AKI has what action on the kidney resulting in pathology
spasm of the afferent arteriole
how fast can you expect to have contrast induced AKI?
immediate toxicity in 24 to 48 hours
how do you prevent contrast induced AKI
1-2 liters NS prior and during and 6 hours after angiography N acetylcysteine 1200 mg po bid on day prior and day of contrast administration
what are the causes of Rhabdomyolysis
trauma, prolonged immobility, snake bite, seizures, crush injury
what is the best initial test for Rhabdomyolysis
urinalysis (dipstick and microscopic) - dipstick will be + for blood, but no RBCs will be seen on the microscopic
what is the most specific lab test for Rhabdomyolysis?
Urine Myoglobin
What will be the important next best step after IV hydration of a patient with Rhabdomyolysis?
EKG
what is the treatment for Rhabdomyolysis
Saline hydration (200-300 ml/hr) Mannitol (osmotic diuretic)Bicarbonate (drives K+ back into cells)
Antibodies and eosinophils attack tubular cells
Allergic interstitial nephritis
What will patients with allergic interstitial nephritis present with
Fever (80%), arthralgias, eosinophilia (80%), rash (50%)
What is the most accurate test to rule out allergic interstitial nephritis?
urine eosinohphils (Wright Hansel stain)
what would be the cause of intrinsic renal injury from small vessel/atheroembolic causes
cholesterol emboli, thrombotic (HUS/TTP, DIC, preclampsia, scleroderma), PAN
What are some causes of intrinsic renal injury
glomerular disease (goodpasture, wegener's, Poststrep)
CHRONIC KIDNEY DISEASE:Stage 3 CKD is a GFR from ____-____GFR below ___ is stage 4 and below ___ is stage 5 which needs dialysis
30-593015
what could you see with patients that have stage IV CKD?
Nephrogenic systemic fibrosis
fibrosis of skin, joints, eyes and internal organs 2-4 weeks post exposure to gadolinium
Nephrogenic systemic fibrosis
what is the most common cause of urethral obstruction?
Benign prostatic hyperplasia
how do you confirm the diagnosis of post renal obstruction?
palpate the bladderultrasound (hydronephrosis, obstruction/stones) Foley catheter for BPH results in high urine volume
what lab values would you see in a patient that has postrenal obstruction?
BUN/Cr ratio > 20:1Urine Na > 40 mEq/L (variable) Fractional excretion of Na > 4% (variable)Urine osmolality < 350 mOsm
what do you have to take into consideration when you have a patient with labs values that correlate with Post renal vs. prerenal causes of pathology
Post renal will have a more significant physical exam
what is the best initial test for AKI
BUN/creatinine ratio
what are the next best tests to run for AKI
urinalysis, urine sodium, fractional excretion of sodium, urine osmalality, urine output, sediment, electrolytes
what is the best initial imaging test for AKI
renal sonogram
what are the complications of AKI
metabolic acidosishypocalcemiahyponatremiahyperphosphatemiahyperuricemia uremia
accumulation of toxic end products from protein metabolism
Uremia
what are some characteristics that would warrant an extremely high risk of developing AKI
Pre-existing CKDElderly with significant co-morbidity Was being treated with ACE inhibitors Poor oral intakeTrimethoprim
what is an adequate treatment for AKI
achieve an adequate BP (MAP > 65 mmHg; better indicator of perfusion to vital organs than SBP)
Sudden onset of flank pain and fever, hematuria2/2 NSAIDs or sudden vascular insufficiency
Papillary necrosis
what does papillary necrosis occur with?
underlying kidney disease seen with DM, sickle cell disease, chronic pyelonephritis
what is the more accurate test for diagnosing papillary necrosis
CT scan (bumpy contour)
what is the treatment for pyelonephritis?
Ampicillin/Gentamicin or Quinolone
What is the difference of the CT scan of a patient with papillary necrosis vs. Pyelonephritis?
Papillary necrosis - bumpy pyelonephritis - diffuse swollen
What types of nephropathy can be caused by NSAIDs
ATN - direct toxicity to tubulesSINMembranous glomerulonephritisPapillary necrosis
Cirrhosis/severe liver disease causes new onset renal failure; looks prerenal (BUN/Cr > 20:1, very low urine Na+, FeNa+ <1%)
Hepatorenal syndrome
what is the treatment for Hepatorenal syndrome
albumin, midodrine, Octreotide
>3 months of reduced GFR (<60 mL/min)
chronic kidney disease
what are some symptoms of chronic kidney disease?
N/V, anorexia, malaise, fetor uremicus, metallic tasteUremic frost, pruritus, calciphylaxis (calcium and phosphate precipitate) encephalopathy, seizures, neuropathy, RLSpericarditis, accelerated atherosclerosis, HTN, HLD, volume overload, CHF, cardiomyopathyAnemia, bleeding
what are the metabolic pathologies associated with CKD
hyperkalemia, hyperphosphatemia, acidosis, hypocalcemia, secondary hyperparathyroidism, osteodystrophy
What will need to be ordered in order to determine CKD diagnosis
UrinalysisCreatinine clearanceCBC (anemia, thrombocytopenia) serum electrolytesRenal US
when would you send a patient with CKD for a nephrology referral?
when GFR <30
how would you correct normocytic, normochromic anemia in a patient with CKD?
epoetin or darbepoetin and iron supplementation
how would you correct hypocalcemia in a patient with CKD
replace Vitamin D and Calcium
How would you correct Hyperphosphatemia in a patient with CKD?
oral phosphate binders (calcium acetate, sevelamer)
how would you correct hypermagnesemia in a patient with CKD?
restrict high Mg+ foods, laxatives, antacids
What would you give to a patient that is suffering from Uremic bleeding
desmopressin (3 mcg/kg intranasally)
what are the major indications for dialysis?
hyperkalemia, metabolic acidosis, volume overload, encephalopathy, pericarditis
what are the different ways to have vascular access in a patient with dialysis?
AV fistula AV graftCentral venous line/catheter
what is the Seldinger technique for central venous line/catheter
subclavian or jugular vein
what are the problems of hemodialysis?
patient may become hypotensive - rapid removal of intravascular volume causing rapid shifts of fluid from the extravascular space into cellshypoosmolality due to solute removal (N/V/HA, seizures)
What type of fistula would a patient have for dialysis if the patient has a scar at the wrist?
forearm radiocephalic
what type of fistula would a patient have for dialysis if the patient has a scar at the elbow
upper arm brachiocephalic
what type of fistula would a patient have for dialysis if the patient has a scar from axilla to elbow
upper arm transposed basilica
where are the transplanted kidneys placed in a patient
iliac fossa; usually the recipient's bad kidney is left in place and the new one is just added.
END LECTURE 7 --------------------------------------------
END LECTURE 7 --------------------------------------------
LECTURE 8 Acid Base --------------------------------------
LECTURE 8 Acid Base --------------------------------------
What will you want to order if a patient has a low bicarbonate
ABG
What is the only anion in our body that we cannot measure
Albumin
How would you treat DKA in the ED
1 Liter NS bolus and drip started6 units regular insulin Sc900 mg Clindamycin IV + 6 million units of PCN G IV Patient admitted to ICU
If you have a patient that is suffering from DKA with a high or normal serum sodium you will give what type of IV fluids
1/2 NS at 250 ml/hr
If you have a patient that is suffering from DKA and you measure the serum sodium to be very low you will want to give what type of IV fluids
NS at 250 ml/hr
When you have a patient that is suffering from DKA and have been treating him with NS at 250 ml/hr. You check glucose which is now at 200 what will you want to do
Change to d5 1/2 NS at 150 cc/hr
How much insulin will you give a patient that is suffering from DKA
0.1 U/kg Regular insulin as IV bolusThen 0.1 U/kg/hr IV drip
T/f if a patient is suffering from DKA you will want to hold off on giving potassium until the patient poops
False(pees)
If a patient is suffering from DKA and the potassium is < 3.3 what will you do
Hold insulin and give 20 K+ until > 3.3
If you have a patient that is suffering from DKA and the serum potassium measures > 5.3 what will you do
Check K+ q2h
If you have a patient that is suffering from DKA and the potassium levels are between 3.3 and 5.3 what will you want to give?
20 K+ in each liter of IV fluid to keep between 4-5
When would you give Hc03 to a patient with DKA
If pH is < 6.9
What are the normal values for pH?
7.34 - 7.45
What are the normal values for pC02?
35 - 45
What are the normal values of HCO3?
22 - 26
PH 7.28, HCO3 = 17, CO2 = 33
Metabolic acidosis
PH = 7.62, HCO3 = 28, co2 = 46
Metabolic alkalosis
Ph = 7.33, Hc03 = 27, co2 = 55
Respiratory acidosis
Ph = 7.55, Hc03 = 21, co2 = 31
Respiratory alkalosis
What are the causes of increase anion gap metabolic acidosis?
MethanolUremia (increase p04, sulfate, rates)DKA, alcoholic or starvationParacetamolIron, isoniazid, Inborn errors of metabolismLactic acidEthylene glycolSalicylatesHypotension/hypoperfusion
What is normal serum anion gap
~ 8-16 mEq/L
What is a pure metabolic acidosis
1-2
If you have an increased anion gap metabolic acidosis what is a good way to determine the anion gap
Value of albumin x 2.5
If you have an increased anion gap what will you want to check for accuracy?
Change in anion gap/ change in bicarb (Calculated AG - expected AG divided by the (24 - Hco3))
If the delta/delta is < 1 what does this mean
Simultaneous AG metabolic acidosis and non AG metabolic acidosis
If the delta/delta is > 2 what does this mean?
Simultaneous AG metabolic acidosis and metabolic alkalosis
With a patient that comes to the ED in DKA and you have been treating them as protocol is established. What will you do with IV fluids if their serum glucose reaches 200
D5 1/2 NS at 150 cc/hr
if serum potassium is < 3.3 wha twill you do
hold insulin and give 20 K+ until > 3.3
what are normal levels of pC02
35 -45
what is normal levels of Hc03?
22 - 26
What are the causes of a increased AG metabolic acidosis?
Methanol UremiaDKA, alcoholic or starvationParacetamolIron, isoniazidLactic acidethylene glycolSalicylateshypotension/hypoperfusion
what is normal serum anion gap
8 - 16 mEq/L
How do you determine the expected anion ga
albumin x 2.5
what is the most common cause of an elevated serum osmol gap
ethanol
if you have an anion gap increased and an osmol gap that is normal what is the most likely cause
acetaminophen and aspirin
how do you measure the calculated osmoles
(2xNa) + (glucose/18) + (BUN/2.8)
if you have an increased anion gap and an increase osmole gap what could this potentially be
Ethanol, methanol, ethylene glycol
if you have a normal anion gap but an increase osmole gap what will this most likely be?
isopropyl alcohol
what is the most common cause of an elevated serum osmol gap?
Ethanol intoxication
If there is normal pH but PCO2 and HcO3- are elevated then you will have?
mixed respiratory acidosis and metabolic alkalosis
If there is normal Ph but Pco2 and Hco3- are decreased then you will have?
mixed respiratory alkalosis and metabolic acidosis
What is the expected compensation for metabolic acidosis?
decrease in Pc02 = 1.2 x the change in HC03-
What is the expected compensation of metabolic alkalosis?
increased in Pc02 = 0.7 x the change in Hco3-
What is the expected compensation for acute respiratory acidosis?
increase in HCo3 = 0.1 x the change in Pc02
What is the expected compensation for chronic respiratory acidosis?
increase in HCO3 = 0.35 x the change in PCO2
What is the expected compensation for acute respiratory alkalosis?
decrease in HC03 = 0.2 x the change in Pc02
What is the expected compensation for chronic respiratory alkalosis?
decrease in HCO3 = 0.4 x the change in PcO2
Where is the pathology of type I renal tubular acidosis
distal convuluted tubule
what is the best initial test if you are worried about type I RTA
urine pH (> 5.5)
what is the most accurate test for type I RTA
infuse IV ammonium chloride
What is the treatment for Distal RTA (type 1)
oral bicarbonate
what are the causes of distal RTA?
SLE, amphotericin, sjogrens
what is the mechanism behind RTA type 2
inability to absorb filtered bicarbonate
what are the etiologies of Proximal RTA
amyloidosis, multiple myeloma, Fanconi's syndrome, acetazolamide, heavy metal poisoning
what is the best initial test for RTA
pH of urine
what is the most accurate test for proximal RTA
administer bicarbonate
what is the treatment of RTA type 2
thiazide diuretics
What type of RTA is hyporeninemic hypoaldosteronism
type 4
where is the pathology in hyporeninemic hypoaldosteronism
distal nephron
what are the causes of RTA type 4
DM
Which RTA will have hypokalemia
proximal RTA
what is the most accurate test for determining type 4 RTA
start low salt diet (oral salt restriction) and monitor effect on sodium lost in urine (still high in type 4)
what is the treatment for Type 4 RTA
Fludricortisone
which urine will be basic in terms of the different types of RTA?
type 1
what are the saline responsive metabolic alkalosis
GI loss of H+ (vomiting)Diuretic uselaxativescystic fibrosis
What are the saline resistant Metabolic alkalosis?
Conn's syndromerenovascular diseaseCushing's syndromeLiddle's syndromeLicoriceBartter's synromeGitelman's syndromeSevere hypokalemia
What does licorice contain
aldosterone
what are the cardiac consequences of severe acid disturbances?
arrhythmias, decreased contractility
what are the respiratory consequences of severe acid disturbances
hyperventilation, decreased respiratory muscle strength
what are the neurologic consequences of severe acid disturbances
AMS
what does hypernatremia mean?
loss of free water
if urine osmolarity comes back < 700 this would be diagnosed as
diabetes insipidus, osmotic diuresis
if urine osmolarity > 800 what is the cause of hypernatremia
vomiting, osmotic diarrhea, fever, seizures, exercise
what are the signs of diabetes insipidus
increased urine volume, decreased urine osmolality, decreased urine Na+
what is the best initial test for diabetes Insipidus
water deprivation test (r/o psychogenic polydipsia)
what is the most accurate test of diabetes insipidus
serum ADH level
what will happen if you decrease the hypernatremia too rapidly
cerebral edema; demyelination of the pontine
what is the rule of thumb for fluid replacement with a patient that presents with hypernatremia?
for every 3 mEq/L > 140 Na+ = 1 liter pure water lost
what are the causes of hypervolemic hyponatremia
CHF, cirrhosis or nephrotic syndrome
what are the causes of euvolemic hyponatremia
pseudohyponatremia, psychogenic polydipsia, SIADH, hypothyroidism
what are the causes of hypovolemic hyponatremia?
fever, burns, pneumonia, sweating, diarrhea, diuretics after chronic replacement with free water
what is the treatment for moderate hyponatremia
NS + loop diuretics
what is the treatment for severe hyponatremia?
3% hypertonic saline, conivaptan
what is the goal for treatment of hyponatremia
increase Na+ 0.5 - 1.0 mEq per hour (12 - 24 mEq/day)
what is the most urgent test for hyperkalemia?
EKG (pealed T, wide QRS, prolonged PR)
if there are EKG changes on a patient that has hyperkalemia what will you do?
calcium gluconate (1-2 amps IV)
If a patient presents with hyperkalemia without EKG changes what is the treatment of choice
Kayexalate (30-90 grams po or pr - sodium polystyrene), Furosemide (>40 mg IV)
what will a patient with hypokalemia present with?
arrhythmia, weakness, paralysis, loss of DTRs
what will you see on EKG of a patient with hypokalemia?
U waves, ventricular ectopy (PVCs), flat T waves and ST depression
what is the treatment for hypokalemia?
oral potassium or IV potassium
what do you want to be sure to check with a patient that has hypokalemia?
magnesium (IV 1-2 grams q 2h)
what are the most common patients for hypomagnesemia?
alcoholics
END Lecture 8 ---------------------------------------------
END Lecture 8 ---------------------------------------------