Electrolytes

Question 1

5 Causes of Hyperkalemia

Answer 1

1) Not! ( hemolyzed)
2) Renal failure
3) acidosis
4) cell death (rhabdo, tumor lysis, crush, burns)
5) drugs ( NSAIDS, ace + Arbs, bactrim)

Question 2

EKG changes with hyperkalemia

Answer 2

1) Peaked T ( 5.5-6.5)
2) Prolonged PR
3) Flat P wave
4) Widening of QRS
5) Sine wave ( 7.5-8)

Question 3

5 things to get when diagnosing Hyperk

Answer 3

1) K level
2) prior K level
3) history
4) physical exam
5) EKG

Question 4

Treatment of HyperK

Answer 4

1) Stabilize the electrical gradient with calcium ONLY in emergencies
- Widened QRS
- Sine Wave
- Heartblock/ Brady
2) Drive K into cell
- glucose + insulin
- beta agonist ( cont alb)
- saline
- bicarb ( only if acidotic)
3) Get K out
- dialysis or lasix

Question 5

Dosing of Calcium in HyperK

Answer 5

1) Calcium Chloride: only give in EMERGENCIES as its highly sclerosing and very concentrated
- 1 Amp = 10 cc
- give a max of 2 amps
2) Calcium gluconate
- give as an infusion

Question 6

Dosing glucose and insulin in hyperk

Answer 6

2 amps of D 50 , 10 unites IV insulin bolus

Question 7

What is the most common and second most common predictor of decompensation in hyperK?

Answer 7

Widened QRS
Brady is the second most common
- this is when you start calcium, dont start calcium with peaked Ts!

Question 8

EKG findings in Hypokalemia

Answer 8

1) Flat T wave
2) U wave
3) Long QT interval ( this is what puts you at risk for vtach, fvib and torsades)
4) Vtach/ vfib
5) non specific T waves

Question 9

What is one thing you ALWAYS give in hypok?

Answer 9

Magnesium

Question 10

Treatment of hypok

Answer 10

1) 10 meq/k/hr in an IV, dont go more than 20 ( 10 in each arm)
2) for a big deficit you can give oral potassium 40-60 ever hour and high potassium and mag foods ( avo, guac, potats, black beans, bananas)
3) 1-2 grams in first hour then .5g/hour maintenance
4) keep treating until QT is normalized - decrease less than 500 and get K in the 3s

Question 11

Causes of hypok

Answer 11

1) Low intake due to diet
2) Excretion via Urine ( diuretics)
3) GI losses ( emesis)
4) transcellular migration

Question 12

How much can you increase sodium in hyponatremia over a 24 hour time period?

Answer 12

8meq

Question 13

Causes of severe hyponatremia

Answer 13

1) SIADH
2) Water excess
3) psychogenic polydipsia
4) Beer potomania
5) hypothyroid

Question 14

Treatment of hyponatremia

Answer 14

100 cc of 3% hypertonic saline, check in 10 minutes and see if asymptomatic ( no seizures, focal findings, AMS)

Question 15

5 reasons for prolonged QT interval

Answer 15

1) hereditary
2) Drugs ( antipsych, anti depressant, antibiotics, Anti epileptics, antifungal, antiarrhythmics
3) electrolytes ( hypok, hypomag, hypocalcemia)
4) structural: subdurals, epidural, MI
5) hypos: hypothermia, hypothyroid
6) bradycardia