Objective: 

Platelets are essential for producing a blood clot. However, there is a high individual variability in the Plt count. This study evaluated the importance of the initial Plt count on oxygen uptake and survival time following a liver trauma in anaesthetized pigs.

Methods: 

A laceration liver injury was inflicted in 19 pigs (34±3 kg; mean±SD). The animals were separated into two groups according to Plt count (Plt_200–350, n=7, and Plt_350–500, n=12). To simulate a pre-hospital setting, the fluid resuscitation was delayed by 7 min. The initial resuscitation fluid was by lactated Ringer's solution, but after 30 min, it was changed to hydroxyethyl starch 130/0.4 to enhance the circulating blood volume.

Results: 

The injury was similar between the two groups of pigs and after 7 min the decrease in arterial pressure (by ~40 mm Hg) and oxygen delivery (by ~50%) did not differ. Although the bleeding rate and the survival time were similar for the two groups (Fig 1), the oxygen uptake was maintained for 60 min in the Plt_350–500 group compared to 50 min in the Plt_200–350 group (P=0.002; Fig. 2). Also, the arterial pressure was maintained at a higher level in the Plt_350–500 group (P<0.001). While the Plt count differed at baseline, the Plt count was similar at 70 min (Fig. 3).

Conclusions: 

Following the liver trauma, the survival time and the bleeding rate were similar for the two groups of pigs. However, the pigs with the highest Plt count were those for whom oxygen uptake was maintained for long enough to secure transport to where surgery might take place.