Fluid resuscitation.

Abstract

Contention over fluid resuscitation is not new. The issues however have changed considerably. The crystalloid/colloid debate has largely reached a stalemate with little to define clear differences between the two especially early in traumatic shock when increased capillary permeability is a minor issue. Blood, despite its difficulties and its cost is now safer than ever before and we will have to wait a number of years before routine use of blood substitutes becomes possible. Hypertonic saline and hypertonic saline dextran solutions used as an early bolus of 4-6 ml/kg and in conjunction with isotonic crystalloids and blood appear to be the new resuscitation fluids of first choice for haemorrhagic shock and there will be a progressive swing towards these fluids over the next 5 years. Application of the principles of minimal volume or delayed resuscitation requires the reconsideration of many entrenched attitudes and expectations present in the traditional management of haemorrhagic shock. Currently there is hard evidence to support its use only in ruptured AAA and penetrating truncal trauma but the application of the principles should be much more widespread. Minimal volume resuscitation emphasizes the need for urgent investigation and definitive management of uncontrollable haemorrhage reserving the early use of fluid resuscitation to maintain life only, until the integrity of the vascular circuit has been verified or restored. Thus it is the timing rather than the quantity of fluid which is the underlying issue. The questions which these new models of haemorrhage raise and the reconsideration of the physiology of haemorrhagic shock must be our focus. It would be foolish to replace the long-held dogma of aggressive fluid resuscitation in all situations with the new dogma of minimal volume resuscitation in all situations. Instead we must walk the tightrope attempting to understand the likely physiological mechanisms of our patients at an individual level. Fluid resuscitation has necessarily become more complex as the potential to do harm has been more clearly demonstrated. The use of resuscitation fluids must now receive as much care and consideration as is currently given to the prescription of potent drugs, weighing the potential benefits of a course of action against its possible side effects. Much research is required to clarify and refine the data on fluid resuscitation but there is little doubt that the conceptual changes which underlie this work on haemorrhagic shock offer the most exciting advances in fluid resuscitation seen in the past 30 years.