Table 1.

Indications for blood transfusion in horses [8].

• Tachycardia

○ The higher the heart rate (HR) the more urgent

○ Severe bleeding may be accompanied by HR > 100 beats/min

• Tachypnoea

○ As above

• Decreased pulse quality

○ Thready pulses

○ Hard or impossible to palpate

• Cool extremities

• Pale mucus membranes

• Mentation changes

○ Anxiety

○ Distress

○ Depression

○ Compulsive thirst

• Hyperlactatemia

○ Serial sampling most helpful

○  Progressive increase indicates decreasing perfusion

• Decreased PCV

○ Acute drop of 10%

○ Absolute PCV < 12–15% usually requires

○ ±Decreased TS