Trial Information

IRB-HSR# 13957: IV Lidocaine for Patients Undergoing Primary Breast Cancer Surgery: Effects on Postoperative Recovery and Cancer Recurrence

Pain after breast surgery is usually treated with narcotics; however, these are associated
with a high incidence of side effects such as itching, nausea and vomiting, constipation,
urinary retention and dizziness. Another modality for pain control is regional anesthesia;
thoracic paravertebral blocks [TPVB] using local anesthetics are particularly appealing for
breast surgery. They provide good pain control, possibly blunting surgical stress response,
and decrease the need for anesthetic agent. However, TPVB are not widely used, and the
inherent risk associated with their placement, such as pneumothorax, nerve injury, bleeding
and infection, makes them less appealing to patients. From a pain management point of view,
paravertebral blocks may be the optimal approach for reducing pain and opiate consumption
after breast cancer surgery. In addition, retrospective data suggest a reduction in cancer
recurrence if this technique is used. Unfortunately, this effective technique is not widely
performed because of the risk of pneumothorax and is only used in some centers. Our intent
is to study an alternative approach with fewer risks.

In this study, we will test the ability of intravenous lidocaine to provide pain relief
after breast surgery. We base our hypothesis on a number of previous trials showing
significant benefits of intravenous local anesthetics in the setting of abdominal
surgery1-4.

Approximately 30 to 50% of patients will develop chronic pain following mastectomy5,6. It
has been suggested that adequately treating pain in the immediate perioperative period will
prevent chronic pain. Specifically, application of EMLA (local anesthetic) cream
perioperatively during breast surgery has been shown to reduce the incidence of chronic pain
development7. Perioperative administration of intravenous lidocaine may offer similar
benefits. Therefore, we will study the incidence of chronic pain in our population after 6
months.

Finally, anesthetic choice during primary surgical intervention for cancer may affect
recurrence and metastasis. A recent retrospective study suggests a profound reduction in
recurrence in breast cancer patients receiving regional + general anesthesia as compared
with general alone9. Similar data have been published in abstract form regarding recurrence
after prostate surgery10. Also, Christopherson et al studied the long-term survival of 177
patients after resection of colon cancer in a trial of general anesthesia with and without
epidural anesthesia and analgesia supplementation for resection of colon cancer. Epidural
supplementation was associated with enhanced survival among patients without metastases
before 1.46 years8. Although the mechanisms of this beneficial effect are unclear,
attenuation of the surgical stress response, modulation of the inflammatory system, and/or
decreased requirement for volatile anesthetics and opiates by regional anesthesia are
possible mechanisms11. For example, the neural inputs activated during surgical stress may
result in activation of promalignant pathways. Morphine has been shown to promote
angiogenesis in a model of breast cancer, a key step in tumor development12. In addition,
opiates interfere with natural killer cell function13. It is conceivable that the beneficial
effect on recurrence might derive from low systemic level of local anesthetics attained
during regional anesthesia. A number of studies have demonstrated significant reduction in
opiate requirements and a decrease in the magnitude of stress response when local
anesthetics are used intravenously1,3,4. If so, systemic administration would be a safer and
a simpler way to reach the same goal. We therefore will compare the effect of local
anesthetics given intravenously as compared with placebo on cancer recurrence rate.