Pain Management & Anesthesia

Pain control for the circumcision is achieved by injecting a small amount of local anesthetic (usually 1 mL of 0.25% Bupivacaine with 1:200,000 epinephrine) in the area where the nerves are located that provide sensation to the end of the penis and the foreskin (penile nerve ring nerve block).

• Injection is done with an extremely thin 27-gauge needle.
• Needle insertion causes minimal pain; however, the medication stings as it enters the body.
• The best analogy for most parents is that the feeling is like the injection that dentists use in the gums prior to a dental procedure.
• To maximize the baby's comfort during the injection, drops of sucrose (sugar water) are given on a pacifier or gloved finger with therapeutic suck to help soothe the baby.

Note: Some parents are concerned that babies should not be drinking sugary liquids. This is correct. We are not feeding the child sucrose; rather, we are flavouring the pacifier or gloved finger with a few drops to encourage the suck and take advantage of the reflex to relax. The babies are not consuming meaningful amounts of liquid.

Bupivacaine is a long-acting local anesthetic and theoretically there should be complete block of any pain sensation for the first 3–6 hours after injection. The local anesthetic doesn't turn off at the 3–6 hour mark. The effects slowly fade away for up to 12 hours, meaning there is some degree of decreased pain for 12–18 hours after injection.

What is normal to see at the injection sites:

• It is normal to see swelling or fullness in the area around the injection sites where the local anesthetic is infiltrated / injected underneath the skin.
• It is normal to see some evidence of bleeding or bruising at the injection sites that will resolve as the circumcision wound heals – over the course of 1–2 weeks.
• It is normal to see blanching (pale colour) in the area around the injection sites (this is from the epinephrine causing slightly reduced blood flow in the area).

The local anesthetic comes pre-mixed with a low concentration of epinephrine. The addition of epinephrine helps in several ways:

• It causes constriction of the small capillaries in the area where the medication is deposited. This means the medication is not cleared away from this area by the blood flow as quickly, increasing the duration of the block.
• Because the medication is not cleared away in the bloodstream as quickly, it lowers the chance of spiking a high concentration of local anesthetic in the blood, thereby lowering the chance of a systemic toxicity.
• The capillary constriction reduces the amount of bleeding during and after the procedure.

Below is a video of one of our doctors administering the penile nerve ring injection while talking through his approach:

Anesthetic creams like EMLA only partially numb the area and wear off quickly. An injectable nerve block provides a complete block of pain sensation for several hours.

Some doctors perform circumcision after application of a topical anesthetic cream (such as EMLA) instead of an injectable nerve block.

• Creams are only partially effective at reducing the sensation of the circumcision and cannot achieve a complete block.
• The duration of action of the cream is much shorter than the injectable medication.
• An injection offers a total block of any pain sensation during and after the procedure for several hours.
• The cream is ultimately absorbed into the bloodstream and processed by the body. So using a cream does not necessarily lower the risk of a drug reaction. In fact, there are some specific drug reactions such as the development of methemoglobinemia which are more likely after use of some topical anesthetic creams due to some specific ingredients which are not as common with use of an injectable anesthetic.

We used to recommend EMLA before the injection, but found it didn't reduce the pain response, the sting comes from a layer the cream can't reach, so we stopped recommending it.

When the clinic first opened, we went through a period of time when we instructed parents to apply a topical anesthetic cream (such as EMLA) over the area where the needle would enter the skin for the nerve block injection. The idea was that we could further improve the pain experience by numbing the skin's sensation of the needle entry and injection.

We found that despite the application of the anesthetic cream, the injection would cause a pain reaction during the injection of the local anesthetic deep to the skin, in the layer that is not reached by the topical cream.

The needle that we use to inject the local anesthetic is very thin, similar to an acupuncture needle. Even without the use of a topical anesthetic cream, we don't see a significant reaction to the needle passing through the skin in most of our patients. In fact, many patients don't react at all to the needle entering the skin (in part because we give sucrose by mouth prior to injection).

Based on these consistent observations, we decided that the application of the cream is not improving the pain experience. Furthermore, even topical creams are absorbed into the bloodstream and can theoretically result in adverse medication reactions. We decided that, on balance, the risks of asking our families to apply a topical cream (theoretical reaction to the medication in the creams) outweighed the benefit (minimal- to no-reduction in the pain response). As such, we have since stopped recommending that parents apply an anesthetic cream prior to arrival.

We pinch a small area of the foreskin before starting. If the baby reacts, that tells us the block isn't complete, we inject more anesthetic and wait.

• Before we begin the procedure, we test by pinching a small area of the foreskin.
• If the baby reacts to this pinch, this is evidence of an inadequate block: we inject more local anesthetic and wait.
• Sometimes we witness discomfort and suspect it may be from other reasons. Babies don't like the experience of lying flat on their backs; they may be gassy, hungry or tired.
• We gauge whether fussiness is due to pain based on whether the crying is in keeping with the surgical manipulation, or independent.
• Though pain sensation is blocked by the local anesthetic, pushing and pulling are still perceived and can also lead to the baby reacting.
• Fussiness and movement will not interfere with the technical success of the procedure.
• The procedure is designed to be safe even with relatively large movements by the baby.

We believe we are doing the maximum to improve the pain experience that can safely be achieved in a clinic setting.

Sucrose is sugar water (a 24% concentration). Tasting it triggers a well-researched calming reflex in newborns, the same technique used in pediatric hospitals during heel-prick blood draws.

• Sucrose is the chemical name for table sugar.
• The use of sucrose is established and used routinely in pediatric hospitals due to a well-researched reflex where newborns relax upon tasting.
• Many parents might have seen sucrose used to help calm their newborns during the heel-prick blood draw or vitamin K injection shortly after birth.
• The concentration we use is shown in the medical literature to maximize the baby's comfort during procedures (24% sucrose in water).
• We apply the sucrose on a pacifier or gloved finger before and during injection and again during the actual circumcision procedure.

There is more to calming babies than the taste of sucrose alone – the staff that give the sucrose have a special skill for calming the babies with gentle touch, shushing and soothing. The entire package is what helps keep babies calm. This is a skill gained through experience.

Even though the penis is completely numbed from the nerve block injection prior to starting the circumcision procedure, we give sucrose to help babies feel relaxed while their legs are gently restrained with Velcro straps, and they are lying flat on their backs.

It is the taste of the sucrose that leads to the reflex to relax. Therefore, we are not feeding the sucrose like you would feed milk. We use a dropper to flavour the pacifier or gloved finger and only use 1–5 mL throughout the entire clinic visit. This is not enough sugar to impact blood sugar or metabolism in a harmful way.

Some parents are concerned that babies should not be drinking sugary liquids. This is correct. We are not feeding the child sucrose; rather, we are flavouring the pacifier or gloved finger with a few drops to encourage the suck and take advantage of the reflex to relax. The babies are not consuming meaningful amounts of liquid.