Local anesthesia involves injecting medication (the local anesthetic) into tissue to make it numb. The medication works so that no pain is felt by the patient but the patient can still feel touch.
The most common medication used as a local anesthetic is Lidocaine. Lidocaine is effective for the majority of patients, but not for all patients. Marcaine, another local anesthetic, may be used for those patients in whom Lidocaine does not work. Because Lidocaine is acidic compared to tissue, doctors may add sodium bicarbonate to Lidocaine so that it will not “burn” when injected into tissue.
Local anesthesia is used when minor surgery is performed. It cannot be used as a sole agent for large surgeries because there is a limit to the amount of local anesthesia that can be used at one time. Local anesthesia is commonly used for minimally invasive breast biopsies, such as ultrasound guided core biopsies and stereotactic breast biopsies, as well as open breast biopsies.
Local anesthesia can also be delivered through a thin tube attached to a reservoir (bulb) that is placed at the time of surgery. This bulb system allows delivery of local anesthesia into a surgical site, such as the site of a mastectomy. The tubing can easily be removed when the bulb containing the anesthesia is empty (typically several days after the surgery).
Regional anesthesia involves injecting medications near nerves, referred to as a nerve block. Regional anesthesia will cause the area to which specific nerves supply sensation to become numb. Regional anesthesia for breast surgery typically involves a paravertebral block or an epidural block. A more recent update to these regional blocks include subpectoral blocks.
With a paravertebral block for breast surgery, the anesthesiologist will inject anesthetic medication near the nerves as the nerves come out of the spinal cord. Typically 4-5 thoracic nerves are targeted, as these nerves provide the sensation to the area of the breast surgery. Bupivacaine is the medication most commonly used for regional anesthesia in breast surgery. Often a paravertebral block will last for 24 hours, delivering pain control both during surgery and after surgery.
An epidural block is what is given to many women during labor. The epidural blocks used for breast surgery target the thoracic nerves which provide sensation to the area of breast surgery, as compared to the lumbar nerves for a “labor epidural”. Epidural blocks involve placing a thin tube (catheter) into the epidural space. This will allow the delivery of the medication to the nerves so that they are bathed in medication and provide continuous anesthesia. Epidural blocks are commonly used for larger breast cases, including patients who undergo mastectomy with immediate reconstruction. The medication delivery system involves a pump so that precise amounts of medication can be delivered.
Subpectoral blocks are also given by specially trained anesthesiologists who administer similar local anesthetics using a needle and ultrasound to various points under the pectoral muscle (chest wall muscle) for pain control.
Paravertebral, epidural blocks and subpectoral blocks are given by specially trained anesthesiologists. Not all facilities have these services available. Also not all patients are candidates to receive these special blocks. Patients who have bleeding problems and patients who are on blood thinners are not able to have these blocks.
General anesthesia involves medication that will make the patient “go to sleep”. The anesthesia provider will give medications (anesthetics) by intravenous injection (IV) that will make the patient unaware of the operation. Frequently the anesthesia provider will “breath for the patient” by placing a tube into the patient’s airway to allow for providing oxygen (breathe in, inhale) and if needed anesthesia gases as well as removing the patient’s carbon dioxide (breathe out, exhale).
LMA intubation, or laryngeal mask airway intubation, is when a tube is placed in the back of the throat to allow this oxygen and gas exchange. This special tube covers the larynx. ET intubation or endotracheal intubation, is when the anesthesia provider places a tube directly into the trachea beyond the vocal cords. The anesthesia provider will choose the method that is best for the individual patient.
General anesthesia is not one medication, but a combination of medications. Anesthesia providers tailor the best combination of medications needed for each individual patient, keeping in mind which operation they will have.
It is important that patients give their anesthesia provider an accurate history of previous anesthetics. No matter what anesthesia is used for an individual, the anesthesia provider and surgeon have many options available to help keep their patient comfortable during surgery.