Recognition of Shock
A systematic approach is required to identify a shocked patient. This starts with an overview of the injured player looking at their colour; are they well perfused or pale from vasoconstriction as the body tries to direct the remaining circulatory volume to the core organs. The standard approach of SABCDE should be used, with emphasis on the respiratory rate, heart rate, blood pressure and conscious level.
The normal circulatory volume is 7% of ideal body weight ~ 70mls per kg. A haemorrhaging patient will mount physiological responses to shock at increasing degrees of blood loss. These can be summarised in the below table:
| Class I | Class II | Class III | Class IV | |
|---|---|---|---|---|
| Blood loss (ml) | Up to 750 | 750-1500 | 1500-2000 | >2000 |
| Blood loss (%) | Up to 15% | 15-30% | 30-40% | >40% |
| Pulse rate | <100 | >100 | >120 | >140 |
| Respiratory rate | 14-20 | 20-30 | 30-40 | >35 |
| Pulse pressure | Normal or high | Low | Low | Low |
| Blood pressure | Normal | Normal | Low | Low |
| Mental state | Slightly anxious | Mildly anxious | Anxious, confused | Confused, lethergic |
During the assessment of a player’s circulation it is essential you take into consideration the fitness state of the player, as their normal resting heart rate may be around 50 beats per minute (bpm), then the parameters we use for normal population are shifted to lower values e.g. a player with a resting heart rate of 50 beats per minute is tachycardic if their heart rate is now 85 beats per minute. Also a fit player is likely to have a good cardiac reserve and therefore only display signs of shock at a late stage, when there is already significant blood loss or circulatory volume redistribution.