Outcome and complications of intraoperative hemodialysis during cardiopulmonary bypass with potassium-rich cardioplegia.
BACKGROUND
Potassium-rich cardioplegia has advantages over other cardioplegic solutions in preserving the myocardium during cardiopulmonary bypass, but it is avoided in patients with renal failure because of hyperkalemia.


METHODS
We first determined the ability of intraoperative hemodialysis (IHD) to remove potassium during cardiopulmonary bypass with potassium-rich cardioplegia in 9 patients by measuring potassium levels in all dialysate and urine. We then studied 24 patients with renal failure, grouped with the 9 previous patients, to assess safety, rebound hyperkalemia, and patient outcome with this technique.


RESULTS
In the first phase, 9 patients were administered 128 +/- 11 mmol of potassium in potassium-rich cardioplegia, and IHD removed 157 +/- 23 mmol. Urinary potassium excretion was only 10 +/- 3 mmol. Potassium removal occurred at a rate of 1.25 mmol/min with 0-mEq/L (mmol/L) potassium dialysate and a rate of 0.75 mmol/min with 3.0-mEq/L (mmol/L) potassium dialysate. In all 33 patients, successful initiation of cardiac rhythm occurred after cardiopulmonary bypass, and 5 patients had cardiac arrhythmias possibly from hypokalemia. In the next 24 hours, 5 dialysis-dependent patients developed hyperkalemia (potassium > 5.2 mEq/L [mmol/L]) requiring hemodialysis. Postoperative hemodialysis was delayed 2 to 3 days in the other patients. The overall death rate was 24% at 30 days.


CONCLUSIONS
IHD effectively and safely removes potassium administered during potassium-rich cardioplegia during cardiopulmonary bypass in patients with renal failure and prevents postoperative hyperkalemia in the majority of patients. Overall mortality in patients with acute and chronic renal failure undergoing cardiac surgery is high irrespective of control of potassium balance in these patients.
Khoo
Michelle S C
MS
Department of Medicine, Baystate Medical Center, Springfield, MA 01199, USA.
Braden
Gregory L
GL
Deaton
David
D
Owen
Susan
S
Germain
Michael
M
O'Shea
Michael
M
Mulhern
Jeffrey
J
Rousou
John
J
Flack
Joseph
J
Engleman
Richard
R
D000368:Aged; D002314:Cardioplegic Solutions / Q000494:pharmacology*; D002315:Cardiopulmonary Bypass / Q000295:instrumentation; D000077324:Crystalloid Solutions; D004867:Equipment Design; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods*; D006331:Heart Diseases / Q000150:complications / Q000601:surgery; D006801:Humans; D006947:Hyperkalemia / Q000139:chemically induced / Q000517:prevention & control; D007430:Intraoperative Care; D007431:Intraoperative Complications / Q000139:chemically induced / Q000517:prevention & control; D007552:Isotonic Solutions; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control; D010952:Plasma Substitutes / Q000008:administration & dosage; D011183:Postoperative Complications / Q000517:prevention & control; D011188:Potassium / Q000008:administration & dosage / Q000494:pharmacology* / Q000652:urine; D006435:Renal Dialysis / Q000295:instrumentation; D051437:Renal Insufficiency / Q000097:blood / Q000150:complications / Q000628:therapy; D016896:Treatment Outcome
D002314:Cardioplegic Solutions; D000077324:Crystalloid Solutions; D007552:Isotonic Solutions; D010952:Plasma Substitutes; D011188:Potassium