for people ages 18-65 (full criteria)
at San Francisco, California
study started
estimated completion
Principal Investigator
by Esther Kim, MD



Despite recent advancements with regional and local anesthesia, postoperative pain continues to be a major concern for patients undergoing breast surgery. Opioids, often in combination with NSAIDS and/or gabapentioids, have been the main pharmacologic pain control strategy in the postoperative period. The pectoral nerve block is a regional anesthetic technique, which is effective at providing postoperative anesthesia in breast surgeries. However, this has only been studied in oncologic-related breast operations. It is our aim to study the effects of pectoral regional nerve blocks in patients undergoing breast reduction for gender affirmation. The overall goal is to establish an effective pain control regimen utilizing regional anesthetic techniques in this patient population. The specific objective of this proposal is to evaluate the effectiveness of these blocks on perioperative and postoperative analgesia. The hypothesis is that participants undergoing gender-affirmation breast surgery who receive a pectoral nerve block will have less perioperative and postoperative pain as well as reduced opioid consumption compared to those receiving a placebo. Participants who are undergoing gender affirmation breast reduction surgery will be randomized to either receive a preoperative nerve block or to receive a placebo. Intraoperative and postoperative opioid requirements will be compared in addition to post-operative pain scores. Participants will be asked to fill out a pain diary during their first week postoperatively. They will also be asked to document if, and when, narcotic pain medication was required for pain control. The two groups will be compared to determine if there was any difference in pain scores as well as narcotic medication requirements.

Official Title

The Effect of Pectoral Blocks on Perioperative Pain in Simple Mastectomy and Breast Reduction in Gender Affirmation Surgery


All participants will be seen in clinic with the attending surgeon anywhere from two weeks to a few months prior to the date of surgery. Participants will also have a pre-op visit with anesthesia a few weeks before surgery. They will undergo a standard anesthesia preoperative evaluation, which will include a medical chart review, physical exam, and appropriate laboratory studies. The preoperative evaluation will be identical for those participating in the study and those who do not. If no contraindications to the Pectoralis Nerve Block (PECS I and II block) are identified by the surgeon and/or anesthesiologist, participants will be approved to participate. The participants will be introduced to the study either during their clinic visit prior to surgery or over the telephone a few days prior to surgery. All questions will be answered by one of the study investigators. A study consent will be obtained from the participants and they will then will be randomized into either control (sham block) or experimental (PECS I and II block) group. On the day of surgery, as per standard of care, each participant will undergo a general anesthetic in the same manner with conventional perioperative management. During induction of anesthesia, up to 2mg of midazolam and/or up to 100mcg of fentanyl will be given. The above protocol will be followed regardless of study participation and study group (if participating). After induction of anesthesia, the nerve blocks, or control blocks, will be performed. The regional anesthesia team will be involved in all patients, whether in the control or intervention group. All patients will be come and go regardless of group. Group 1 (control) will receive an injection of 20ml of saline between the pectoralis minor and serratus anterior muscles bilaterally and 10ml of saline between the pectoralis minor and pectoralis major muscles bilaterally. Group 2 (treatment) will receive an injection of 20ml of 0.2% Ropivacaine between the pectoralis minor and serratus anterior muscles bilaterally and 10ml of 0.2% Ropivacaine between the pectoralis minor and pectoralis major muscles bilaterally. (Not to exceed 225mg or 3.5mg/kg). PECS I and II Block Technique: Performed in the supine position with the arms abducted 90 degrees at the shoulder. Using an ultrasound transducer in the parasagittal plane, the axillary artery and vein are identified just inferior to clavicle and medial to coracoid process. Additionally, the 2nd rib is identified and the transducer is slid inferiorly until the 3rd and 4th rib are identified. At this point the pectoralis major, minor, and serratus anterior muscles are seen. Then the block needle is inserted through the skin and advanced into the fascial plane between pectoralis minor and serratus anterior muscles. After negative aspiration, the anesthetic is injected into the plane watching for hydrodissection of the muscles. A total volume of 20ml is injected. Then the needed is withdrawn until the tip is located in the fascial plane between the pectoralis major and minor muscles. 10ml of anesthetic is injected into this plane. General anesthesia is maintained in the standard fashion. The anesthesiologist will administer Fentanyl as he or she feels necessary during the operation. Post operatively, in the PACU, participants will be given IV hydromorphone as needed for pain. Pain scales will be documented at set time points post operatively and participants will be given pain diaries to document these pain scores as well as their opioid consumption. All patients will be sent home with a prescription for 20 tablets of Norco 5mg/325mg. Participants will be asked to document their pain scores at the following post op time points: 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24 hours, 48 hours, 72 hours, 1 week. Participants will return their pain diaries at the 1 week post operative visit. This visit is a standard of care follow up visit.


Gender Dysphoria Opioid Use Pain, Postoperative Ropivacaine Ropivacaine 0.2% Injectable Solution Saline (0.9%) Saline


You can join if…

Open to people ages 18-65

  • American Society of Anesthesiologists (ASA) class I-III
  • Ages 18-65
  • Undergoing gender confirmation breast reduction surgery by a single surgeon at a single center

You CAN'T join if...

  • Previous breast surgeries
  • Current breast cancer or history of treatment for breast cancer
  • Current chronic pain syndromes
  • Coagulopathy
  • Allergy to local anesthetics
  • Infection at the injection site


  • University of California, San Francisco
    San Francisco California 94143 United States

Lead Scientist at UCSF


accepting new patients by invitation only
Start Date
Completion Date
University of California, San Francisco
Phase 4
Study Type
Last Updated