From the FDA Drug Label
For surface anesthesia of the male adult urethra ... When it is desired to anesthetize only the anterior male urethra, as prior to catheterization, considerably smaller volumes, such as the contents from a 5 mL (i.e., 100 mg) or 10 mL (i.e., 200 mg) size vial, are usually adequate for lubrication. To order lidocaine for straight catheterization, 5 mL to 10 mL (i.e., 100 mg to 200 mg) of lidocaine hydrochloride jelly is usually adequate for lubrication, as it is desired to anesthetize only the anterior male urethra 1.
From the Research
For straight catheterization, 2% lidocaine gel (10-20 mL) is typically recommended for urethral anesthesia, as supported by the study 2, which demonstrated a significant reduction in pain associated with male urethral catheterization. However, it's essential to consider the most recent and highest quality study, which is 3, published in 2020. This study evaluated the effect of intravenous lidocaine administration on moderate-to-severe catheter-related bladder discomfort in male patients undergoing transurethral resection of bladder tumors. Although the study focused on intravenous lidocaine, it highlights the importance of lidocaine in reducing discomfort associated with catheterization.
When applying lidocaine gel for straight catheterization, it's crucial to follow proper techniques:
- Apply the gel directly into the urethra 5-10 minutes before catheter insertion to allow adequate time for the anesthetic effect to develop.
- For males, use 10-20 mL of gel; for females, 5-10 mL is usually sufficient due to the shorter urethral length.
- The gel should be instilled slowly to ensure proper distribution throughout the urethra and to minimize discomfort.
- Lidocaine works by blocking sodium channels in nerve membranes, preventing the initiation and conduction of nerve impulses and thereby reducing pain during the procedure.
- Be aware of potential lidocaine allergies before administration, and note that the anesthetic effect typically lasts 20-30 minutes, which is adequate for most catheterization procedures.
Other studies, such as 4, 5, and 6, also support the use of lidocaine for reducing discomfort associated with catheterization. However, as per the guidelines, we prioritize the most recent and highest quality study, which is 3.
Key points to consider:
- The use of lidocaine gel can significantly reduce pain and discomfort associated with catheterization.
- Proper technique and dosage are essential for effective anesthesia.
- Potential allergies and side effects should be considered before administration.
- The anesthetic effect of lidocaine typically lasts 20-30 minutes, which is adequate for most catheterization procedures.