Intravenous fluids for abdominal aortic surgery

Surgery on the abdominal aorta, for aneurysmal and occlusive disease is a major undertaking which requires intensive support and fluid management. Blood products are often used, but the major fluid replacement is with crystalloids or colloids. There has been controversy for many years over which fluid is optimal and a number of studies have examined this subject, without any systematic review.

The objective of this review was to determine the effectiveness of different non-blood replacement fluids used in surgery on the abdominal aorta with a view to identifying the optimal fluid for use in such surgery.

All publications describing (or which might describe) randomised controlled trials of non-blood replacement fluids in abdominal aortic surgery were sought using the search strategy described by the Cochrane Review Group on Peripheral Vascular Diseases. This strategy includes hand searching of relevant medical journals and extensive MEDLINE and EMBASE searches. In addition, trials have been identified from searches of references included in those trials already retrieved.

Randomised controlled trials assessing the effects of one or more specific non-blood fluids used for replacement therapy in operations on, and confined to, the abdominal aorta.

Data were extracted to pre-prepared tables and then entered into the Review Manager software where statistical analysis and descriptive subjective analysis were performed.

Nine trials, involving 412 patients were included. Patients undergoing aortic surgery had various physiological parameters measured before and after their operation (cardiac, respiratory, biochemical, haematological and protein). Ten fluids were studied: Ringer lactate, 5% dextrose in Ringer lactate, 5% dextrose in 0.45% saline, 5% dextrose in water, 1.8% saline, human albumin solution in Ringer lactate, human albumin solution in water, 5% dextrose with human albumin solution, Dextran 60, Hetastarch. Patients were randomised to fluid type. This review demonstrates that no single fluid has been shown to affect any outcome measure significantly more than any other across a range of outcome measures. However, each trial compared different fluids, and each fluid has not been compared against all others. The death rate in these studies was 2.9% (12 patients).

Further studies are required, with sufficient sample size and power, to draw any further conclusions. There are no studies examining the effects of combination fluid therapy.