Stroke Volume Index Calculator
The Stroke Volume Index Calculator estimates SVI based on stroke volume, height, and weight. This tool helps medical professionals assess cardiac function and monitor hemodynamic status in patients. Whether you are evaluating heart failure, managing sepsis, or guiding fluid therapy, this calculator provides accurate data to support critical treatment decisions.
How Stroke Volume Index Is Calculated
SVI = Stroke Volume (SV) / Body Surface Area (BSA)
Where:
- BSA = √(Height (cm) × Weight (kg) / 3600)
The Stroke Volume Index (SVI) represents the volume of blood the heart pumps per heartbeat, normalized for body surface area. This adjustment is crucial because it allows doctors to compare heart function fairly across patients of different sizes. First, the calculator determines the Body Surface Area (BSA) using the trusted Mosteller formula. Then, it divides the stroke volume by the BSA to find the final index. Using this specific method ensures high accuracy and standardization, helping clinicians reliably identify abnormal cardiac function in critically ill patients.
What Your Stroke Volume Index Means
Your SVI result provides a clear picture of how efficiently the heart is pumping blood relative to the patient's body size.
| SVI Range (mL/m²) | Status | Clinical Implication |
|---|---|---|
| < 33 | Low | May indicate hypovolemia, heart failure, or cardiogenic shock. |
| 33 - 47 | Normal | Indicates optimal cardiac function and adequate perfusion. |
| > 47 | High | May suggest sepsis, anemia, or other hyperdynamic states. |
Important: SVI is a dynamic measurement, so trends are often more valuable than single readings. Sudden changes can signal patient deterioration or improvement before other vital signs shift.
This tool is for educational purposes only and should not be used for clinical decision-making. It is not a substitute for professional medical advice. Always consult a qualified healthcare provider for diagnosis and treatment.
Monitor SVI trends over time rather than relying on a single snapshot to effectively guide fluid management and drug therapy.