- Turkish Journal of Thoracic and Cardiovascular Surgery

New Method for Delivering Contiuous Normothermic Blood Cardioplegia

Belli E. MD, Le Houerou D. MD, Romano M. MD, Lessana A. MD.

Department of Cardiovascular Surgery Hopital Europeen de Peris L Roserae, Aubervillies, France

To avoid the pitfalls of the Fremes solution with a 4:1 ratio, we describe an undiluted cardioplegia delivery method aiming to optimize the oxygen delivery and reduce the systemic hemodilution or potassium (K) overload. Arresting agents,potassium chloride (KCI) and magnesium sulfate (MgSO4), are; directly injected via two syringe drivers in the cardioplegia line withdrawn rom the arterial line. Cardioplegic K level (p, hgh=25 mmol/l, low=12 mmol/l) needs to remain constant. The KCI infusion rate (q1, ml/h) depends on cardioplegia blood flow (Q ml/mn), patients serum K level (k, mmol/l) and injected KCI concentration (K mmol/l); this rate is derived from the following equation:

q1= 60.Q.(p-k)/K-p

The flow rate of MgSO4 (10%) is function of Q (q2=0.48.Q) in order to obtain a Mg2+ concentration of 6 mmol/I.
We have now operated on more 2000 patients. We compared results in 300 consecutive patients with those obtained in 300 provious patients receiving the Fremes solution. Our method avoided an overload of KCI (4.8+0.7 vs 5.5±1.5 mmol/l, p<0.05), resulted in a better myocardial oxygen delivery (hemoglobin=9.1±0.4 vs 6.8±0.4 g/dl p<0.05) and necessitted lower volmes of cristaloid inisuon (80±29 vs 1717±88 ml, p<0.001). diluted hyponatremia an hyperglycemia indued by the Fremes solution and related consequences were not observed.

Viewed : 1471

Downloaded : 0