Since the 90's, the quality of the post operative pain relief is a main concern in most of the healthcare systems in the world. An efficient pain relief improves the quality of recovery after surgery [Level 1A], reduces the risk of persistent pain [level 1A] and makes the patients satisfied.

Continuous regional anesthesia/analgesia promotes a level 1A in quality of postoperative pain relief, reduction in opioids consumption in opioid sparing/free analgesia programs, time to recover and the reduction of hospital stay. However in the postoperative period, breakthrough pain episodes due to mobilization or activity are not well covered by regional analgesia. Furthermore, after removal of the catheter of regional anesthesia, patients may face an unpleasant rebound pain effect.

At VinMec, the technique of regional anesthesia chosen to provide regional analgesia after hysterectomy is a bilateral erector spinae plane block .

Traditional Medicine relieves pain by non-pharmacological methods, especially by acupuncture which bring positive results. Acupuncture has been proven to provide pain relief according to the mechanism of traditional and modern medicine, safe for patients and with few side effects. The acupunture point formula is used by VinMec Sao Phuong Dong Traditional Medicine Center in conjunction with the department of Anesthesiology and Pain management in VinMec Times City International General Hospital to relieve pain after hysterectomy including: Three Yin Intersection (SP-6), Leg Three Miles (ST-36), Taichong (LR-3), Xuehai (SP-10).

The study is to observe the effect of combining acupuncture with regional anesthesia on pain relief and postoperative recovery in patients undergoing hysterectomy.

There is no published study regarding the effects of combining the 2 techniques above as multimodal approach for post operative analgesia after hysterectomy.

Design A single center, open label, prospective randomized controlled trial to study the benefits of combining acupuncture with bilateral continuous ESPB compared to bilateral ESPB alone in patients scheduled for an hysterectomy .

Patient selection At the pre-anesthetic consultation or performed at least 24h before the surgery.

Enrollment and allocation During the pre-anesthetic consultation, if the patient accepts the proven benefits to have surgery performed under combined general anesthesia and regional anesthesia, the anesthesiologist will offer her to participate in the study comparing these two bundles of care using regional anesthesia.

Patients will be assigned via a random number generator into one of two study groups (1 Or 2) by the physician/nurse who obtained consent which is prescribed in the nurse preparation file.

Surgical technique Elective hysterectomy by laparoscopic or Pfannenstiel incision

GROUP 1: ESPB

The ESPB will be performed after the induction of general anesthesia (Décris ton régime d'anesthésie générale). (Kit epidural for adult Tuohy needle 19 G Catheter 20G, Name company). Once hemodynamically stable, the patient will be placed on right lateral decubitus. Right and left side level of puncture is on transverse process of T8 in cephalo-caudal direction. The tip of the catheter should be on the transverse process of T9.

During the ultrasound-guided procedure, the ESP space was located by injecting dextrose 5% to lift up the fascia of the erector spinae muscles off the transverse process. There should be a visible spread of fluid in both cephalad and caudal directions and demonstration of a breathing sign. The catheter 20G will be inserted into this space under US guidance, visualizing the tip of the catheter on the top of the next transverse process, as described above. The catheter placement will be tested by injecting dextrose 5% and demonstrating a cephalo-caudal spread of the liquid in the inter-fascial plane anterior to the ESP muscle. Induction of ESP block will be done 30 min before incision with ropivacaine 0.5% with loading dose as follows:

Patient height (cm) Volume of LA (mL) LEFT RIGHT 140-149 8 6 150-159 10 8 160-169 12 10 170-180 14 12 >180 16 14

Group 2: ESPB combined to Acupuncture Patient will have ESP bilateral catheter as per group 1

Three hours after the surgery, acupuncture will be performed as per the following protocol:

Acupuncture point formula

1. Three Yin Intersection (SP-6): 3 cun above the the highest point of the ankle bone, one finger's breatdth from the posterior border of the tibia
2. Leg Three Miles (ST-36): 3 cun below the knee crease, and approximately one finger's breadth lateral to the tibial crest. It is located near the anterior shin bone muscle, and in a depression between the the fibula and tibia..
3. Taichong (LR-3): put the foot flat on the floor, on the dorsum of the foot, find the point in a depression distal to the junctions of the 1st and 2nd metatarsal bones.
4. Xuehai (SP-10): on the medial border of the patella, in the middle of vastus medialis and sartorius muscle.

Material Acupuncture needle, diameter = 0.25mm, 4cm long, needle material: SUS 304; manufactured by Van Long Medical Equipment Co., Ltd, Wujiang City, China.

Sessions of Acupuncture The patient lies in supine position, with two legs exposed. Acupuncture for 30 minutes,

• At Day 0 The first session will be 3 hours after arrival time in post operative care unit
• At day 1 2 and 3, 2 sessions per day, at 8 am and 3 pm (acupuncture done before the patient starts to do exercises).

Acupuncture performed on both legs. Order of acupuncture points: Three Yin Intersection (SP-6), Leg Three Miles (ST-36), Taichong (LR-3), Xuehai (SP-10)

Acupuncture performed in 2 steps:

• Step 1: needles puncture through the skin at the acupuncture points quickly and decisively.
• Step 2: When needle depth is about 0.5-1cm, manipulate the needle every 10 minutes counterclockwise. At Taichong (LR-3), manipulate the needle every 10 minutes counter-clockwise

Statistical consideration Statistical analysis The study is a superior comparative trial. Patients scheduled for hysterectomy will be randomized into 2 groups: a group receiving standard of care ESPB and a group receiving ESPB + acupuncture. Comparison between groups done for primary and secondary outcomes.

Sample size Assuming the difference in VAS score between two group is 1, variance of VAS score is 2 and equal between two groups, for 95% CI and power of 80%, 32 participants are needed for each group. Assuming loss of follow-up is 10%, a total of 72 participants (36 for each group) is needed.

Analysis plan For primary outcome (VAS score), t-test will be used for the comparison between group. For secondary outcomes, Mann-Whitney test will be used for continuous outcomes and Fisher's exact test will be used for categorical outcomes. All statistical tests are 2 sided with significant level of 0.05.

All analysis will be done with latest version of R statistical software.

Data collection For the first 3 postoperative days, data will be recorded during routine patient rounds done by the anesthesia team in the ICU and surgical ward. Another set of data will be recorded after one month, during routine patient follow-up.

All data will be retrieved from the patient records except for opioid consumption which will be obtained from the PCA pumps. Opioid consumption will be recalculated to morphine milligram equivalents (MMEs).

For pain evaluation, VAS score will be assessed every 2 hours after extubation for 3 consecutive times, and every 8 hours thereafter. Please see table below.

A dedicated anesthesia nurse trained for data collection will follow the patient and collect the data

V. ETHICS Independent Ethics Committee or Institutional Review Board Approval will be obtained from VinMec ethical committee (IRB) and signed by the IRB/IEC chairman or designee before human participants participate in research studies. Before study onset, the protocol, informed consent, advertisements to be used for the recruitment of study participants, and any other written information regarding this study to be provided to the participant or the participant's legal guardian must be approved by the IRB/IEC. Good Clinical Practice (GCP) will be maintained and will be available for review by the Sponsor or its designee.

The investigator is responsible for providing written summaries of the progress and status of the study and written reports on any changes significantly affecting the conduct of the study or increasing the risk to participants.

The study will be performed in accordance with the ethical principles that originated from the Declaration of Helsinki, ICH GCP, and all applicable regulations.

Participant Information and Consent A written informed consent shall be obtained from each participant before entering the study or performing any unusual or nonroutine procedure that involves risk to the participant.

Before recruitment and enrollment, each prospective participant or his or her legal guardian will be given a full explanation of the study, allowed to read the approved ICF, and allowed to have any questions answered. Once the investigator is assured that the participant/legal guardian understands the implications of participating in the study, the participant/legal guardian will be asked to give consent to participate in the study by signing the ICF. The authorized person obtaining the informed consent will also sign the ICF.

Inclusion Criteria:

• female
• elective hysterectomy
• accept ton participate
• signed consent

Exclusion Criteria:

• patient refusal
• allergy to local anesthetics
• complex congenital malformation
• mental deficit
• substance abuse(alcohol, drugs, opioids)
• renal insufficiency

Patients listed for hysterectomy