A pulse oximeter is a non-invasive medical device used to measure the oxygen saturation level (SpO₂) in your blood and your pulse rate. It’s widely used in hospitals, clinics, and even at home for monitoring respiratory or cardiac conditions.
🔧 How It Works
- Clips onto Finger, Toe, or Earlobe
- Emits Red (660 nm) and Infrared (940 nm) Light
- Light Passes Through Tissue
- Photodetector Measures Light Absorption
- Calculates Ratio of Oxygenated to Deoxygenated Hemoglobin
- Displays SpO₂ % and Pulse Rate
📊 Normal SpO₂ Reading
- 95% – 100%: Normal
- 91% – 94%: Mild hypoxemia (monitor closely)
- Below 90%: Medical attention required (possible hypoxia)
✅ Common Uses
- Monitoring patients with respiratory conditions (e.g., COPD, asthma, COVID-19)
- During anesthesia or surgery
- High-altitude sports or activities
- Sleep apnea assessments
- Health tracking in smartwatches & fitness bands
⚠️ Limitations / Accuracy Factors
- Cold fingers
- Nail polish (especially dark colors)
- Movement or shaking
- Poor circulation
- Skin pigmentation
- Low perfusion
📦 Types of Pulse Oximeters
| Type | Description |
|---|---|
| Fingertip | Most common for home use |
| Handheld | Used in hospitals (with probe & screen) |
| Wrist-worn | Used for continuous monitoring |
| Smartwatch-based | For fitness and casual tracking only |
🛒 Popular Pulse Oximeter Brands (India)
- Dr. Trust
- BPL Medical
- Beurer
- Choicemmed
- HealthSense
- Omron