71 y/o ESRD pt. on HD presenting with Hyperkalemia
Dr. Eric Siddall | Morning Report | 08/04/2016
Hyperkalemia - Can lead to muscle paralysis, Arrhythmia
ECG findings - peaked t-waves, loss of p-wave, pr-depression
Acuity of K change is more important than absolute number. Ex: someone chronically with with K of 6 now with K of 7 at lower risk than someone with K of 4 whose K is now 6.5.
Treat with Calcium Gluconate only if ECG changes (stabilizes cardiac membrane potential). Calcium gluconate will only last ~30 min. Sodium Bicarb less effective in HD patients (also is more effective when the Bicarb is low) Insulin works well to lower K+ but need to be cautious in HD patients as the Insulin is renally cleared (will not be cleared in ESRD) Kayexelate Only works in the colon, does not work in acidic environments (so takers a long time to act). Association with intestinal necrosis is uncertain.
Posted 08/04/16 10:35:46 AM by Adam Faye
Think of Rhabdo, TLS as possible causes
Stenosis of fistula can also decrease clearance during HD and lead to ineffective HD
**Digoxin inhibit Na/K ATPase - inhibition of the channel leads to hyperkalemia** --> In such instances, Digibind can improve hyperkalemia.
Posted 08/04/16 11:09:54 AM by Adam Faye
Immediate labs at the end of HD are not useful. Transiently the K shifts intracellularly so the K will appear lower than it actually is. Would have to check a BMP about 30 min. after HD
"Good" dialysis session - If urea decreases by more than 70%
Posted 08/04/16 11:28:56 AM by Adam Faye
Grafts can be used earlier than AVF for HD, but has the disadvantage of having a foreign object in place
Caution with ABGs in a arm with AVF. Any vascular damage can cause stenosis which can lead to additional steal from the artery (some of the flow is already been shunted towards the fistula) - can see cold hand, parasthesias etc.
Posted 08/04/16 11:30:21 AM by Adam Faye
ACEi/K-sparing diuretics can still increase K+ in ESRD patients since 30% of K is still excreted in the colon.