What technique reduces pain on injection of lidocaine?

What technique reduces pain on injection of lidocaine?

• A. Warming the Solution
• B. Buffering With Sodium Bicarbonate
• C. Using a Smaller Needle
• D. Slow Injection

Answer: (B)

Pain on injection from lidocaine mainly comes from the acidity of the solution, which irritates tissues as it’s injected. Buffing the lidocaine with sodium bicarbonate raises the pH toward normal tissue pH, increasing the portion of lidocaine in the non-ionized form that readily crosses nerve membranes. This reduces the burning sensation and often allows for a faster onset of anesthesia. In practice, a small amount of sodium bicarbonate is added to the lidocaine (eg, mixing a small volume of 8.4% bicarbonate with lidocaine with epinephrine) and the mixture is used promptly. The idea is to neutralize the acidity surrounding the anesthetic, making the injection more tolerable. Other methods like warming the solution, using a smaller needle, or injecting slowly can help with pain, but buffering directly targets the chemical cause of the sting and provides the most consistent reduction in injection pain.

Pain on injection from lidocaine mainly comes from the acidity of the solution, which irritates tissues as it’s injected. Buffing the lidocaine with sodium bicarbonate raises the pH toward normal tissue pH, increasing the portion of lidocaine in the non-ionized form that readily crosses nerve membranes. This reduces the burning sensation and often allows for a faster onset of anesthesia.

In practice, a small amount of sodium bicarbonate is added to the lidocaine (eg, mixing a small volume of 8.4% bicarbonate with lidocaine with epinephrine) and the mixture is used promptly. The idea is to neutralize the acidity surrounding the anesthetic, making the injection more tolerable. Other methods like warming the solution, using a smaller needle, or injecting slowly can help with pain, but buffering directly targets the chemical cause of the sting and provides the most consistent reduction in injection pain.