A Comparative Study of the Haemodynamic Effects of Urapidil and Sodium Nitroprusside In Deliberate Hypotension During General Anaestheia

Abstract

Deliberate hypotension is the elective lowering of arterial blood pressure, provided that tissue perfusion is preserved. The primary advantages of the ideal technique are minimization of blood loss during surgery to reduce the need for blood transfusion and lower the risk of its complications, and better wound visualization in some types of surgery as in microsurgery, cancer surgery or head and neck surgery. It may also have advantages in vascular and plastic surgery.

The minimum effective level of deliberate hypotension should be provided, to avoid possible complications. In general, a decrease of MAP to 50-65 mm Hg at the surgical site is believed to decrease blood loss significantly.

The contraindications to deliberate hypotension have relaxed over the years. However, limitations to the use of deliberate hypotension are present in patients with uncontrolled hypertension, myocardial ischaemia, cerebrovascular disease, respiratory disease, renal, hepatic or heart failure, anaelllia, hypovolemia, and pregnancy.

The ideal hypotensive technique doesn't exist yet. Thus many techniques for deliberate hypotension have been suggested, each having its advantages and disadvantages.