The myocardial protective effects of a moderate-potassium blood cardioplegia in pediatric cardiac surgery: a randomized controlled trial.
BACKGROUND
We investigated the myocardial protective effect of a moderate-potassium cold blood cardioplegic solution (K+, 10 mmol/L) in pediatric cardiac surgery.


METHODS
Sixty-eight pediatric patients with congenital heart disease and undergoing open heart surgery with cardiopulmonary bypass were randomly allocated to the high potassium (HP [K+, 20 mmol/L, n=31]) cold blood cardioplegia group or the moderate potassium (MP [K+, 10 mmol/L, n=37]) cold blood cardioplegia group. Heart arresting time, rhythm recovery time, mechanical ventilation time, inotropic drug use in the intensive care unit, perioperative serum cardiac troponin I concentrations, morbidities, and mortalities were compared between the two groups.


RESULTS
There were no differences in cardiopulmonary bypass time, aorta cross-clamping time, cardioplegia volume, lowest body temperature during cardiopulmonary bypass, total volume of cardioplegia delivered, hematocrit value, and fluid output during the operation between the two groups. However, there was a longer arresting time and a shorter rhythm recovery time in the MP group (35.6±2.4 s, and 30.8±3.1 s) when compared with that in the HP group (24.7±2.7 s, and 42.0±4.0 s, both p<0.05). The total mediastinal drainage volume, the length of stay in the intensive care unit, the postoperative inotropic drug use, and the postoperative hospital time were similar between the two groups, but the number of patients with a long postoperative mechanical ventilation time (>24 hours) in the MP group (6 of 36) was less than that in HP group (13 of 30; p<0.05). At 1 hour, 3 hours, and 6 hours after myocardium reperfusion, the serum concentration of cardiac troponin I significantly decreased in the MP group (in ng/mL: 15.18±3.57, 24.83±4.91, and 19.62±3.93, respectively) when compared with that in the HP group (in ng/mL: 32.67±5.31, 39.26±7.43, and 30.52±5.17, respectively, p<0.05).


CONCLUSIONS
The present study demonstrated that the M (10 mmol/L) cold blood cardioplegia formula is associated with better myocardial protective effects when compared with conventional HP cardioplegia in pediatric patients.
Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Yang
Y
Liu
Sheng-li
SL
Zhang
Wei-xun
WX
Duan
Lan-ping
LP
Lei
Shi-qiang
SQ
Yu
Xin-hong
XH
Qian
Zhen-xiao
ZX
Jin
D006348:Cardiac Surgical Procedures / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006324:Heart Arrest, Induced / Q000379:methods*; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods; D007223:Infant; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D017680:Potassium Compounds / Q000494:pharmacology*; D011446:Prospective Studies; D016037:Single-Blind Method; D016896:Treatment Outcome
D017680:Potassium Compounds; C018369:potassium cardioplegic solution