How is EMLA (lidocaine and prilocaine) cream used for pain management before a circumcision procedure?

EMLA Cream for Pre-Procedure Pain Management in Circumcision

EMLA cream (lidocaine-prilocaine) should be applied to the penis under occlusive dressing 60-80 minutes before circumcision to provide effective topical anesthesia, though it provides inferior pain control compared to dorsal penile nerve block (DPNB). 1, 2

Application Protocol

Timing and Technique

• Apply 0.5-1.0 gram of EMLA cream to the penile skin 60-80 minutes before the procedure under an occlusive dressing to achieve adequate anesthetic effect 2
• EMLA requires the full 60-minute application time to reach effectiveness on intact skin, which is longer than newer alternatives 3
• The cream should be applied to intact skin only; non-intact skin is a contraindication 4

Age-Specific Considerations

• For infants under 7 months of age, EMLA provides effective anesthesia with 92.5% experiencing little or no pain during circumcision 5
• Reduce the dose for patients under 12 months old or weighing less than 10 kg 4, 3
• Infants over 7 months have more difficulty settling post-procedure, regardless of anesthetic method used 5

Efficacy Evidence

Pain Reduction Outcomes

• EMLA significantly reduces behavioral pain responses (facial activity, crying time) and physiologic responses (heart rate increases) compared to no anesthesia 2
• However, EMLA provides significantly inferior pain control compared to DPNB during circumcision (pain scores 4.8 vs 2.3, with heart rate increases of 49 vs 9 beats per minute) 1
• When used as an adjunct before DPNB, EMLA effectively eliminates needle penetration pain but does not reduce pain during local anesthetic infiltration 6, 7

Clinical Success Rates

• 99% of infants under 7 months fed immediately post-procedure, 96% settled rapidly, and 96.5% had no sleep disturbance when EMLA was used 5
• When EMLA is used prior to local anesthetic ring block in children aged 3-13 years, conversion to general anesthesia is significantly reduced (1/89 vs 7/82 in placebo group) 6

Safety Profile

Contraindications

• Allergy to amide anesthetics 4, 3
• Recent sulfonamide antibiotic use (trimethoprim-sulfamethoxazole, erythromycin-sulfisoxazole) 4, 3
• Congenital or idiopathic methemoglobinemia 4, 3
• Non-intact skin 4, 3
• Avoid in infants under 12 months receiving methemoglobin-inducing agents 4

Adverse Effects

• Methemoglobin levels remain safe (approximately 1.3% of hemoglobin concentration), similar to placebo 2
• Mild erythema may occur at application site in approximately 14% of cases 1
• Lidocaine and prilocaine are detectable in plasma in 55-61% of treated infants, but at safe levels 2
• No serious complications attributable to EMLA cream have been reported 5

Clinical Decision-Making Algorithm

For neonates and infants under 7 months:

• Use EMLA alone (0.5-1.0g for 60-80 minutes) if DPNB expertise is unavailable or parents prefer non-invasive anesthesia 5, 2
• Preferentially use DPNB over EMLA alone for superior pain control 1
• Consider EMLA as pre-treatment before DPNB to eliminate needle penetration pain 6, 7

For children over 7 months:

• EMLA alone is insufficient; use as adjunct to DPNB or ring block 6
• Apply EMLA 60 minutes before local anesthetic injection to reduce needle pain 6

Important Caveats

• EMLA does not provide complete pain relief and parents should be counseled accordingly 4, 3
• The cream only anesthetizes superficial skin layers and does not reach the dorsal penile nerves located under Buck's fascia 7
• Avoid mucous membrane contact or ingestion during application 4
• Acetaminophen should be used cautiously if concurrent EMLA application is planned, as both can contribute to methemoglobin formation 4