Question
The names Brechner and Bethune are associated with which of the following devices?
| A. |
Precordial Doppler |
| B. |
Transesophageal echocardiography |
| C. |
Plethysmography |
| D. |
End tidal capnography |
Show Answer
|
Correct Answer » D Explanation |
 |
- Brechner and Bethune pioneered end-tidal carbon dioxide (ETCO₂) monitoring, which forms the basis of capnography.
- Capnometry is the measurement of carbon dioxide (CO₂) concentration in expired gas.
- Capnography is the continuous graphical recording of CO₂ concentration throughout the respiratory cycle (capnogram).
- ETCO₂ monitoring is now a standard monitor during general anesthesia, intensive care, and cardiopulmonary resuscitation (CPR).
Why Other Options are Incorrect
A. Precordial Doppler ultrasound
- Used for detecting venous air embolism.
- It is not associated with Brechner and Bethune.
B. Transesophageal echocardiography (TEE)
- Most sensitive investigation for detecting venous air embolism.
- Not pioneered by Brechner and Bethune.
C. Plethysmography
- Measures changes in volume (e.g., blood flow or lung volumes).
- Not related to Brechner and Bethune.