Anaesthesia for microvascular surgery. A physiological approach.

The anaesthetic management of patients for microvascular free transfer surgery requires a sound knowledge of circulatory physiology. It is important to maintain adequate arterial pressure and cardiac output. Hypervolaemic haemodilution to a haematocrit of about 35% increases the cardiac output and improves flow in the microcirculation. Systemic heat loss must be minimized and the transplant itself kept warm. Hypocapnia is to be avoided. Analgesia must be adequate. The degree of any induced vasodilatation must be balanced against the effect on the systemic arterial pressure. Measures instituted in theatre to produce optimum circulatory conditions must be maintained in the postoperative period.