---

---

---

---

Science Current Events and Science News RSS Feeds

---

---

Email a Friend Printer Friendly

A new and safer technique in heart surgery

May 17, 2004

The new technique of SELECTIVE CEREBRAL PERFUSION has been successfully applied for the first time in the Basque Autonomous Community (B.A.C.).

Surgeons keep a patient in a state of hibernation at 15 degrees centigrade, without brain activity and with heart circulation and respiratory activity at a standstill for one hour while an aorta implant is fitted.

The technique enables operations involving aorta pathologies to take place in greater conditions of safety, thus avoiding possible brain damage which can occur in this type of operation.

Last week the Heart Surgery Service at the Policl'­nica San José in the Basque Country capital of Vitoria-Gasteiz applied this pioneering technique of Selective Cerebral Perfusion when operating on a patient to have an aorta replacement.

The main advantage of this new technique is that it provides greater cerebral protection during this type of operation, enabling the patient to be kept in a state of hibernation (15ºC) and with the brain, blood circulation and respiration at a standstill, for more than an hour, compared with the 30 minutes that hibernation techniques used to date have allowed.

The technique is one more step in Heart Surgery advances, given that, to date, this type of operation has been carried out in a state of hibernation and with perfusion through the cerebral veins. Using a technique involving selective arterial perfusion of the brain provides a greater margin of safety and thus avoid brain damage and posterior neurological consequences.

At the Policl'­nica San José in Vitoria, the team led by Dr. Ignacio Gallo has applied the technique in a patient who had a saccular aneurysm of the aortic cavity (thickening of the aortic artery wall which grows due to blood pressure) of up to 8 x 8 centimetres.

During the operation, the patient is kept for 60 minutes in hibernation at a temperature of 15 degrees, with the heart and the blood circulation system halted. During this time, the brain is maintained and protected with the brain Perfusion System, the main novelty in this class of operation. Thanks to this system, the patient's brain receives a small quantity of blood via a canula installed in the subclavian artery (axillary), while the rest of the circulatory system is halted.

Apart from the use of the Brain Perfusion System during the operation, the Heart Surgery Service at the Policl'­nica San José used - also in a pioneering way - a Dacron tube connected to the axillary artery in order to carry out the perfusion, in place of perfusion via the femoral artery which has taken place up to now.

The technique step by step

In order to carry out an aorta aneurysm operation and, as is usual in these cases, it is necessary to cool the patient (deep hypothermia) to 15 degrees centigrade in order to halt circulatory, respiratory and cerebral activity, assuring that no damage occurs to the brain and other vital organs (this process lasts 35 minutes). The blood cools by means of an oxigenator with an external heat exchanger through which the extracorporeal circulation circuit passes. Likewise, the patient's brain is protected in ice.

The main novelty of the technique being applied by Dr. Gallo in this case is that, once the heart, circulatory system and respiratory and cerebral activity have been halted, a SYSTEM OF SELECTIVE CEREBRAL PERFUSION was established which perfuses by means of a canula placed in the axillary artery. In this way, the brain receives blood while the rest of the circulatory system is kept on hold.

Once the patient is in a state of hibernation and perfusion is being carried out on the brain, the operation can start. Here, the heart surgeons at the Policl'­nica San José have substituted the tract of the defective aorta (aneurysmal-dilated) with an implant using a synthetic prothesis suture of Dacron, which carries out the functions of the new aorta. The new prothesis is connected to the blood vessels to the brain (this process lasts an hour).

Once the prothesis is implanted, the blood circulation system is re-established and the process of warming up the body is (this process lasts 50 minutes). After checking on the correct functioning of the heart, any tubes and perfusion circuits are removed and the operation can be terminated.

Elhuyar Fundazioa