Anesthesia Technologist Practice Exam

For deeper blocks, which ultrasound probe frequency is recommended?

1. 1-2 MHz

2. 2-3 MHz

3. 3-5 MHz

4. 5-7 MHz

The correct answer is: 3-5 MHz

The recommended ultrasound probe frequency for deeper blocks is in the range of 3-5 MHz. This frequency strikes a balance between tissue penetration and image resolution. Lower frequencies, such as those found in the 1-2 MHz range, penetrate deeper into the body but provide lower resolution images, making it harder to visualize smaller anatomical structures. Conversely, higher frequencies, such as 5-7 MHz, offer much better resolution and detail, which is beneficial for superficial structures but is less effective for deeper tissues due to their limited penetration. In the context of deeper blocks, having adequate visualization of deeper nerves and surrounding structures is crucial for effective anesthesia delivery. Therefore, the 3-5 MHz range is optimal for achieving this goal, allowing for better identification of deeper nerves while still maintaining enough resolution to ensure accurate placement and assessment.