Acid Base Review Flashcards
Normal pH
7.35-7.44
normal bicarb
24
normal paco
40
normal anion gap
12
normal osmolar gap
10
What does GOLD MARK stand for?
glycols 5-oxoproline L lactate D lactate methanol aspirin renal failure ketoacidosis
Winter’s formula
1.5xBicarb +8 +/- 2
Anion gap formula
Na - (HCO3+Cl)
Osmolar gap fomula
measured - calculated osmolarity
Osmolarity equation
2*Na + glucose/18 + BUN/2.8
Delta-delta gap equation
delta gap: Calculated anion gap - normal anion gap
delta bicarb: 24 - delta gap
if the measured bicarb was greater than what we calculated here, then theres metabolic alkalosis as well
if the measured bicarb was less than what we calculated here, then there’s NAGMA as well
Diagnosis of osmolar gap mnemonic
ME DIE methanol ethanol diethylene glycol isopropyl alcohol ethylene glycol
NAGMA diagnosis mnemonic
DURHAMM diarrhea ureteral diversion renal tubular acidosis hyperalimentation acetazolamide addisons disease miscellaneous
What is the effect of acidosis and alkalosis on potassium levels?
acidosis - hyperkalemia
alkalosis - hypokalemia
What is the difference in presentation between glomerular and non glomerular hematuria?
glomerular will have RBC casts, new proteinuria, elevated serum creatinine
non glomerular: more likely to have visible blood clots
What is the first thing to consider in work-up of hematuria?
urine culture
What are the features of IgA nephropathy?
IgA deposits in mesangium
hematuria associated with a viral infection
1-2 days after infection present with dark urine
What are the clinical features of Renal Cell Carcinoma
gross hematuria
flank pain
mass
fever and weight loss
What is the next step for imaging of RCC?
CT or MRI
When is PSA and DRE not recommended for screening of prostate cancer?
when the man is asymptomatic
what increases a patient’s risk for prostate cancer?
primary degree relative
If you suspect urinary tract stone disease, what is the primary concern?
concomitant infection (surgical concern)
How do you diagnose urinary tract stone disease?
flank pain, frequent UTIs, nausea/vomiting, stone on imaging
What are the considerations in transient urinary incontinence?
DIAPPERS delirium infection atrophic vaginitis pharmaceuticals psychosocial/psychiatric excess urine stool impaction
What are the common causes of fever?
infection
autoimmune disease
CNS disease (head trauma, mass lesion)
malignancy (lymphoma, leukemia, RCC, liver cancer)
How do you calculate urine anion gap?
(urine Na + Urine K) - Urine Cl
What does it mean if UAG is positive?
the distal nephron is unable to acidify the urine.
What does it mean if UAG is negative?
distal nephron is able to acidify the urine
What is the etiology of proximal RTA Type 2?
primary - idiopathic/heriditary
secondary - cystinosis in children and fanconi syndrome in adults
What are the clinical manifestations of proximal RTA?
NAGMA hypokalemia (mild compared to distal RTA type 1)
How to diagnose proximal RTA?
urine pH can be high or low depending on serum bicarb. can have urine pH <5.5
UAG can be positive or negative
What is the pathophysiology of Distal RTA type 1? 2 causes?
decreased secretion of H+ ions in distal nephron so distal RTA is unable to acidify the urine.
- H/K ATPase and H ATPase
- gradient defect - H flows back into tubular cell
What is the etiology of Distal RTA type I?
- primary - idiopathic or hereditary
- secondary - sjogrens syndrome, or glue sniffing
What is the clinical manifestation of distal RTA type I?
nephrolithiasis or nephrocalcinosis
How can you diagnose distal RTA type I? (4 things)
- NAGMA
- patients are unable to acidify their urine pH <5.5
- hypokalemia (severe)
- UAG is positive
What is hyperkalemic RTA type 4?
distal nephron dysfunction from impaired renal excretion of H and K causing a NAGMA and hyperkalemia
What are the two etiologies of RTA type 4?
deficiency of circulating aldosterone
- diabetes mellitis
-drugs such as NSAIDS, ACEI
aldosterone resistence in collecting ducts
- interstitial renal disease (sickle cell nephropathy, obstructive uropathy, lupus)
-drugs such as amiloride, triamterene, spironolactone
What is the pathophysiology of hyperkalemic RTA type 4?
impaired Na reabsorption by principle cells leading to decrease in luminal negativity of CD, which impairs acidification as a result of decreased driving force of H secretion.
What are the clinical manifestations of hyperkalemic RTA type 4? (theres 4)
asymptomatic
NAGMA
hyperkalemia
history of diabetes or CKD
Diagnosis of hyperkalemic RTA type 4?
Variable urine pH, usually >5.5
UAG is positive
