1. What is Blood Flow Rate?

Definition: Blood flow rate (Q_b) is the volume of blood that passes through a given cross-section of a blood vessel per unit time.

Purpose: This measurement is crucial in cardiovascular physiology, helping assess circulatory function and diagnose vascular conditions.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q_b \) — Blood flow rate (mL/min)
• \( V_b \) — Blood velocity (cm/s)
• \( A_v \) — Vessel cross-sectional area (cm²)

Explanation: The product of blood velocity and vessel cross-sectional area gives the volumetric flow rate.

3. Importance of Blood Flow Rate

Details: Proper blood flow ensures adequate oxygen and nutrient delivery to tissues and organs. Abnormal flow rates may indicate cardiovascular diseases.

4. Using the Calculator

Tips: Enter the blood velocity in cm/s and vessel cross-sectional area in cm². Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a normal blood flow rate?
A: Varies by vessel: ~5 L/min for cardiac output, ~84 mL/min for renal arteries, ~50 mL/min for common carotid arteries.

Q2: How is blood velocity measured?
A: Clinically measured using Doppler ultrasound or other imaging techniques.

Q3: Why is vessel area important?
A: Flow rate is directly proportional to cross-sectional area - narrower vessels require higher velocity for same flow.

Q4: Does this account for pulsatile flow?
A: No, this calculates mean flow rate. Actual flow varies during cardiac cycle.

Q5: How does viscosity affect flow?
A: This simple formula doesn't include viscosity. Poiseuille's Law would be needed for more precise calculations.