Hypokalemia
Hypokalemia
Established correctable cause of hypokalemia (medications, diarrhea etc)
Serum K+ <3.5 but >2.5
QTc < 550
Normal cranial nerve and cerebellar exam
No evidence of acute intracranial processes on CT head, if obtained.
Must be able to tolerate PO repletion (IV repletion is SLOW)
Pre-existing long QT syndrome
Prolonged PR interval, ST Depression, Formation of QU complex or QTc > 550
K+ <2.5
Serum Bicarb < 18 - especially if hypophosphatemic. That's probably a type 2 RTA and you wouldn't want to deprive an IM resident the opportunity to care for that
No clear cause of hypokalemia
Inability to tolerate PO repletion
Cardiac monitoring
BMP Q4-8hr depending on severity
Check serum Magnesium on admit. If < 1.2 mg/dl, then give Magnesium Sulfate (2 grams over 30 minutes) and recheck on next labs. Continue repletion (can repeat every 2 hours) until serum mag >2.2 mg/dl
Medication
Anti-emetics. Consider even if not vomiting, PO potassium can be a bit harsh
Loperamide if Diarrhea and no contra-indication (e.g. C. Diff)
IV Fluids - correcting dehydration is an important part of treating hypokalemia. Preferred fluid is 0.9% NS in this case
Oral Potassium Repletion
IF Serum CO2 (bicarb) is < 25
Potassium Citrate 40 meq Q4 hours (tastes like tang, better tolerated than other forms of K+)
IF Serum CO2 is > 25
Potassium Chloride (K-Dur) Tablet 20-40 Meq PO Q4 hours
IV Potassium Repletion
Generally only necessary for more severe hypokalemia (<2.8)
Patient's hate it (it burns) and it's slower than oral repletion
Should not be necessary for most CDU level patients
Can be given as an ADJUNCT to oral repletion while in CDU
Potassium Chloride 10 meq IVPB over 1 hour.
Can repeat PRN
Disposition
Serum K+ > 4.0
Cause of Hypokalemia identified and treated
DCIs for hypokalemia
Repeat outpatient labs / PCP visit in 1 week
Tolerating PO, Diarrhea controlled
Low dose oral potassium supplement as needed at time of discharge
Development of arrhythmia, worsening QTC prolongation, QRS prolongation, QU complex or ST depressions.
Serum K+ <3.0 after 18 hours of treatment in CDU
Not tolerating PO
Ongoing loss of K+ not controlled (Vomiting, Diarrhea etc)
Abnormal vitals, Altered Mental Status
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