| Blood loss, % (mL) | Systolic blood pressure, mmHg | Signs and symptoms |
| 10 to 15 (500 to 1000) | normal and ≥90 | Palpitations, lightheadedness, no or mild increase in heart rate |
| 15 to 25 (1000 to 1500) | 80 to 90 | Weakness, sweating, tachycardia (100 to 120 beats/minute), tachypnea (respiratory rate of 20 to 24) |
| 25 to 35 (1500 to 2000) | 70 to 80 | Restlessness, confusion, pallor, oliguria, tachycardia (120 to 140 beats/minute), cool and clammy skin |
| 35 to 45 (2000 to 3000) | 50 to 70 | Lethargy, air hunger, anuria, collapse, tachycardia (>140 beats/minute) |
