Termination of cardiopulmonary bypass is a critical step in any cardiac surgical procedure
and requires a thorough planning. Debate about rationale of calcium administration during
weaning of cardiopulmonary bypass has been conducted for several decades; however, a
consensus has not been yet reached.
Perioperative hypocalcemia can develop because of haemodilution or calcium binding from
heparin, albumin and citrate. Perioperative hypocalcemia is often complicated by development
of arrhythmias, especially QT interval prolongation. Furthermore, low content of calcium can
lead to vascular tone disorders, violation of neuromuscular transmission, altered hemostasis
and heart failure, resistant to inotropic agents, especially in patients with concomitant
cardiomyopathy.
On the other hand, hypercalcaemia is a dangerous complication in cardiac surgery. Among the
fatal, but rather rare complications, there are acute pancreatitis and the phenomenon of the
"stone heart", which is essentially a reperfusion injury of the myocardium caused by rapid
calcium overload. Hypercalcaemia can also trigger rhythm disturbances, hypertension, increase
systemic vascular resistance, reduce diastolic compliance and impair relaxation of the
myocardium due to excessive calcium intake into the cardiomyocytes, cause coronary vasospasm
and aggravate ischaemic myocardial damage, impair arterial graft blood flow during
aortocoronary and mammary coronary bypass surgery.
To date, there is a lack of data indicating clinical efficacy of calcium administration
before separation from CPB. Therefore, we designed this randomized controlled trial to test
the hypothesis whether calcium administration at termination of CPB will reduce the need for
inotropic support at the end of surgery.
Phase:
Phase 4
Details
Lead Sponsor:
Meshalkin Research Institute of Pathology of Circulation