What needle gauge is recommended for a PSA block with an adjusted depth of penetration?

• A. 27 gauge short needle
• B. 25 gauge long needle
• C. 30 gauge short needle
• D. 27 gauge long needle

Answer: (A)

When placing a PSA block, having precise control over how deep the needle goes is crucial because you’re aiming for a relatively shallow target near the posterior maxilla. A fine, short needle gives you the best balance of tactile feel, control, and safety. The 27-gauge short needle is thin enough to minimize tissue trauma and pain while still being sturdy enough to aspirate and inject the anesthetic effectively. The short length helps you stay within the intended depth and reduces the risk of over-penetration or hitting deeper structures. A longer needle could lead you past the target, and a thicker gauge would create more resistance and potential discomfort. So, the 27-gauge short needle is the best fit for achieving the adjusted depth with good control and safety.