HTKCustodiol

HTKCustodiol is a crystalloid cardioplegia solution used to protect the heart during cardiac surgery and to preserve donor organs in transplantation. It is based on the histidine-tryptophan-ketoglutarate (HTK) formulation, commonly referred to as Custodiol. The solution is designed to induce myocardial arrest while reducing ischemic injury by providing a buffered, low-calcium environment and supplying metabolic substrates. Mannitol helps limit edema, and ketoglutarate serves as an energy substrate during preservation.

The solution is typically cooled to about 4°C for administration. It may be delivered as a single initial dose or, in some protocols, in multiple doses depending on the procedure and institutional preference. Delivery methods include antegrade infusion via the aorta or coronary ostia, and in some cases retrograde infusion through the coronary sinus. Dosing varies by patient and procedure, with common ranges roughly in the order of 10–30 milliliters per kilogram, depending on the protocol and planned duration of protection.

Clinical considerations and evidence: HTKCustodiol is valued for providing myocardial protection with limited hemodilution and, often, reduced need for repeated dosing. Compared with blood-based cardioplegia, outcomes are broadly similar across many studies, though results can vary by patient population and surgical context. Potential drawbacks include electrolyte disturbances, risks of hypotension during delivery, and variable protection in certain high-risk conditions; monitoring and adherence to protocol are important.

See also: Custodiol, HTK solution, cardioplegia, organ preservation.