Dehydration: A Dangerous Consequence

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Yet more evidence of the importance of rehydration after exercise comes from a rather terrifying British case report of three young sportsmen who developed the potentially fatal trauma complication, fat embolism syndrome (FES) after sustaining tibial shaft fractures while playing football.

On presentation at the hospital, none of the men showed signs of shock; their fractures were immobilised immediately and they were kept on a nil-by-mouth régime, without intravenous fluids, until the following afternoon, when their fractures were fixed.

All three patients developed FES post-operatively and, although two made a full recovery with supportive oxygen therapy, the third died.

FES is a poorly-understood condition, complicating up to 3.5% of isolated fractures of the long bones, with mortality rates of up to 15%. What seems to happen is that fat droplets from the bone marrow enter the circulation via ruptured veins at the fracture site and are then carried in the blood to the lungs, causing a severe inflammatory reaction.

Since animal studies have shown dehydration to increase the risk of FES after trauma, the authors of the report, based at Hillingdon Hospital in Middlesex, set out to test the hypothesis that mild dehydration was a factor in these cases. They did this by measuring the specific gravity of the urine of 20 patients presenting to accident and emergency on a weekend after sustaining musculoskeletal injuries during sport and comparing the results with tests carried out on ten members of staff.



Their suspicions were confirmed when they found a significant difference between mean values for the two groups, confirming that the sportsmen and women were relatively dehydrated.

‘The importance of adequate resuscitation from shock is universally accepted in trauma management,’ comment the authors. ‘However, the potential role of dehydration in the development of FES in the absence of shock is less well appreciated. We postulate that patients sustaining injuries during sport are likely to have some degree of dehydration on presentation. These patients will be unlikely to drink large volumes when being admitted and settled on a ward and when being given strong analgesics with sedative effects.’

Patients kept nil-by-mouth without intravenous fluids pre-operatively are then likely to develop further dehydration, they point out. ‘Thus patients who, by the nature of their injury, are already at risk of developing FES may be being placed further at risk by a failure to correct dehydration.’

The authors suggest that particular attention should be paid in future towards hydration of patients with long bone fractures requiring surgical treatment – particularly if their injuries were sustained during heavy exercise. Giving them intravenous fluids when on a nil-by-mouth régime pre-operatively might reduce their risk of developing FES.

Injury 2002 Nov;33(9):757-759