11 - Electrolyte Imbalance Flashcards
Potassium imbalances
- Extra-cellular K rises as pH decreases
- Medicines, GI issues, renal problems and pH changes are primary causes of imbalances
Hypokalemia causes
- Diuretics
- GI losses (diarrhea)
- Alkalosis
- Low magnesium
Hypokalemia signs and symptoms
- Cramps or fatigue
- Paresthesias
- Dysrhythmias, flat t waves, ST depression
- She has never been able to see flat T waves or high T waves from high or low potassium
- Ileus (belly ache, nausea)
Hypokalemia treatment
- ***Replace slowly (PO or IV)
- ***If you give it fast, heart problems, burning IV and arrhythmias
- 3.5 – 5 is normal; admit if below 2.5
- Oral replacement is usually adequate and less risky (20 -40 meq K in a liter ok…more IV and nurses get very nervous plus burns)
Hyperkalemia causes
- Hemolysis - #1 cause of high K result ***
- Meds
- Metabolic Acidosis
- As the acidosis is corrected, K will go back into the cell leading to hypokalemia
- Renal failure #1 true medical reason ***
- Rhabdomyolsis
Hyperkalemia signs and symptoms
- Hyper-reflexia, paresthesia, weakness
- Tented T waves***
- V-fib, heart block, death
Hyperkalemia treatment
- Albuterol
- Lasix
- Insulin + glu
- Calcium gluconate, calcium chloride
- Kayexalate (not so much anymore)
When does one check potassium?
- Often before surgery (not always)
- Renal issues
- Meds
- Part of BMP(chem 7)
- Rhabdo concerns
- GI issues
Hypoglycemia
- BS
Treatment of hypoglycemia
- Sugar
- Glucagon (IM or IV) - Hypoglycemia, Cocaine overdose, Food caught in the throat (smooth muscle relaxer)
- This one you can treat quickly…don’t give them oral if they can’t swallow (hard candy)
- If known diabetic and don’t know BS – give sugar
Hyperglycemia
- Reasons beyond diabetes (steroids, stress, infection)
- Increased glucose levels cause delay in healing/decreased mortality in hospital if managed
- Very high sugar – feel cruddy for days, panting
- Serious consequence is DKA
DKA
- Acute, deadly consequence of DM (usually type I)
- Frequently follows GI illness (or is GI illness part of DKA?)
- Give fluids, fluids and more fluids
- Then give insulin; when BS hits 250, give glucose
- Add potassium (starts high, decreases with rx)
**How do you know if it is DKA? **
- Clinically – tachypnic…trying to blow off acids by panting and getting rid of CO2 - Patient will be PANTING ***
- Sweaty and vomiting
- Confused or anxious or combative or nonresponsive
- ABGs will show low pH, low CO2, low bicarb
- Blood/urine + ketones
Hyperosmotic hyperglycemic state (HHS)
- Type II diabetic equivalent to DKA
- Sugars not as high – treatment the same
- People can be just as sick as in DKA
- Glu >600, Osmo>320, ph >7.3, bicarb >15, not many ketones
- “I don’t see this as much, not as common, but the treatment is the same”
When do you check sugars?
- Screens (FMH, age, surgery)
- Acutely- confusion, N/V
- Part of BPM
- Chronically, vision changes, wt loss, polydipsia, neuropathy
Calcium imbalances
- Regulated by PTH, vitamin D and calcitonin
- Need liver, kidney, skin and GI system for balance
- Phosphorus and calcium inversely related
Hypocalcemia causes
- Meds
- Metabolic disorders
- Surgical mishap (parathyroid glands)
- Pancreatitis (low Ca bad sign), CA
- Renal/liver problems (via vitamin D)
Hypocalcemia signs and symptoms
- ***Tetany/muscle spasm
- Seizures
- Fractures
- Decreased cardiac output
- ***Chvostek sign (tap facial nerve)
- ***Trousseau sign (inflate BP cuff/carpal spasm)
- LOW calcium = spasms
Hypocalcemia
- ***Always check an albumin prior to saying someone is hypocalcemia
- ***If they have a low albumin, it causes the calcium to be low
- Add .8 of Ca to every 1.0 decrease in albumin
- Albumin of 2, calcium of 7
- (4 – 2) X 8 = 1.6 add to 7 = 8.6 real calcium level
Hypocalcemia treatment
- Treat underlying cause
- Replace slowly (tums works)
- HCTZ
Hypercalcemia causes
- PTH
- Meds (thiazides)
- Cancers
- Metabolic (high thyroid, low phos)
- Immobilization
- PTH and CA account for 90%
Hypercalcemia signs and symptoms
- Muscle weakness
- Fatigue
- Nausea
- Bone pain
- Anorexia
- Has to be pretty high to get symptoms
Hypercalcemia treatment
- Calcitonin
- IV phosphorus
- Lasix
- Bisphosphonates
- IVF
- Dialysis
When does one check Ca+?
- Osteoporosis
- Part of most BMPs now
- Concern of parathyroid disease
- Cardiac arrhythmias
Sodium imbalances
- Essential in water/volume balance
- Influenced by thirst, ADH, renal-angiotensin
- Increased osmo (280-300) stimulates thirst and ADH
- Hypovolemia stimulated Na absorption
Hyponatremia signs and symptoms ***
- Confusion***
- Nausea/vomiting*
- Cramps*
- Often no s/s (especially if chronic)*
3 types of hyponatremia
- Hypovolemic
- Euvolemic
- Hypervolemic
Hypovolemic hyponatremia
Easiest to figure out – pt is dehydrated, but has lost salt > water o GI losses o Exercise o Burns o Pancreatitis o Meds
Hyponatremia treatment
- Correcting the fluid loss usually takes care of it – give isotonic saline (NS)
Euvolemic hyponatremia
- HARDEST to figure out
- Volume is ok, sodium low
- Psychogenic (or drinking too much H2O)
- Hypertriglycerides
- Hyperglycemia
- SIADH
- Meds
- Infection
- Adrenal or thyroid disorders
Pseudohyponatremia
- Low Na secondary to increase in lipids
Transitional hyponatremia
- Secondary to hyperglycemia (Na goes into cells to equalize osmolality)
- Na decreases 1.6 meq for every 100 mg/dl increase in glucose
- Na will correct when glucose does
SIADH
- Syndrome of inappropriate antidiuretic hormone secretion
- A big cause of euvolemic hyponatremia (1/3 of low sodium)
- Low plasma osmolality, high urine osmolality, plus high urine Na
Causes of SIADH
- Cancers (oat cell, small cell, ovarian, lymphoma) can secrete ADH
- Infection
- Trauma
- Meds (prozac, TCAs, anti-seizure, chronic alcohol)
SIADH treatment
- Fluid restriction
- Oral Na
- Democlocycline
New treatment option
- Vaptans – ADH receptor antagonists
- Works because fixing SAIDH is a slow process, this speeds it up
- All you need to know is that it is an ADH receptor antagonist ***
Hypervolemic hyponatremia
- Caused by CHF, renal disorders or liver cirrhosis
- Treat with water restriction – tough to fix because they often have fluid but not in vessels – some add loops + fluids
- With these, often have to improve the underlying cause
Replacing sodium
- If you replace sodium too quickly, can get central pontine myelinolysis**** (irreversible)
- Use NS unless having acute neurological symptoms like seizures
- If critical symptoms, then can use 3% saline – Oral better bet
- KNOW THIS – BOARD QUESTION
- Two things to correct very slowly = potassium and sodium
Hypernatremia
- Not common
- Can be from fluid loss, meds, renal impairment, burns
- See anxiety, tremor, spasticity, seizure
Diabetes insipidus
- ADH failure
- Either central or renal
- Water wasting – get hypotonic urine
- Meds (lithium, demeclocycline)
- Note: Opposite of SAIDH – you’re peeing out a lot of water
Treatment of diabetes insipidus
- Central – DDVAP
- Nephrogenic – thiazide diuretics
Hypernatremia
- Treat with fluids
- If replace too quickly, can get brain swelling***
When to check sodium
- Part of BMP
- Confusion
- Muscle cramps, burns, illness
Magnesium
Increased levels cause N/V, weakness, hypotension, diminished DTR
o Renal, iatrogenic (pre-eclampsia, asthma, torsades de pointes), rhabdo
o Read on your own
Decreased levels causes muscle cramps, hyper reflexes, psychosis, arrhythmias
o Illness, renal issues, malnutrition, EtOH can lead to decreased levels
Giving a fluid bolus
- ***Done for clinical dehydration or to correct vital signs
- ***Always use isotonic (NS or LR)
- ***A bolus is only a bolus if it is given quickly (wide open does not equal bolus)
- A bolus is squeezing the bag until it is all in – Within 20 minutes
How much to bolus?
- ***In children, it is 20 ml/kg
- May repeat 3 times, rarely worry about CHF
- Adults – more eyeball the volume
Maintenance fluid needs
- Weight Volume/hr
- 1st 10 kg 4 ml/kg/hr
- 2nd 10 kg +2 ml/kg/hr
- Any above +1 ml/kg/hr
Urine output
- In children, want 1-2 ml/kg/hr
- In adults, .5-1 ml/hr (
Buzz words for boards
- Hyperkalemia – Tented t waves, cardiac issues
- Hyponatremia – confusion, central pontine myelinolysis
- Hypocalcemia – tetany (physical tests that cause spasms) 9
Case study 1 – Edith
Patient presentation
o Elderly woman with confusion
o Recently started Prozac
Deadly causes of confusion
o Stroke
o Sepsis
o Trauma
Common causes of confusion o Infection (UTI, pneumonia, cellulitis) o Electrolyte (hyponatremia) o Medication (changing 4-5 meds)
Case study ROS
ROS
o Dizzy, loss of appetite
o Nausea, no vomiting
o Urinary “problems” (incontinence, has to go all the time, no blood)
o No fever or chills
o Last time she ate was yesterday
o She has not had this before
o She has not had falls, but feels unsteady
o No chest pain, no SOB, no recent weight loss
Medications o Lisinopril (get basic labs - BMP) o Levothyroxine (order TSH) o Prozac (can cause confusion, can cause sodium issues)
Physical exam
o Neuro exam (no signs of stroke)
Case study labs
EKG = Normal
CBC (WBC = 14.2, Hbg = 12, Hct = 36, Platelets = 350)
o UA (Positive nitrites, Positive leukocytes, Positive blood, Ketones) o BMP (with liver enzymes = CMP) - Sodium = 123 (135-145) o TSH = 1.2 o Lactic acid (shows if they’re septic) = 0.6
Case stud cause
o Likely UTI caused the hyponatremia o Serum osmolality = 253 (low) o Urine osmolality = 980 o Urine Na = 99 o This means all the sodium is going from the serum into the urine (called SIADH)
Hyperkalemia case
- Patient skipped dialysis - Potassium is not pulled off, so they are hyperkalemia
Potassium
o 3.5-5.1 mEq/L (she said 3.5 to 5.5)
o Even if potassium is just a little high, we get concerned
Dialysis
o Best thing for her
o But not always possible at rural hospitals
Other treatment
o Diuretics
o Calcium gluconate
o Glucose and insulin, which puts potassium back into the cell
o Albuterol puts potassium back into the cell = short term fix, but still helpful
Fluids
o Give fluids (low BP) – first priority to get her BP up and keep her alive
o Give diuretics (to get rid of the fluids)
