Acute pain after cesarean section (SC) can be variable. Untreated pain can affect patients' life quality. Currently regional nerve blocks are frequently used as a part of multimodal analgesia. Erector spina plane block (ESPB), a recently defined interfacial plane block, provides multisegmental analgesia by spreading to both ventral and dorsal branches of the spinal nerve roots in the cranio-caudal plane with a single injection. The aim of this study is to evaluate the effects of ESPB on postoperative pain, analgesic use and patient satisfaction in patients delivered by CS under spinal anesthesia.

Cesarean section (CS) is one of the most common surgical procedures in the world. Acute pain intensity after cesarean section can be variable, making difficult to predict pain severity. Untreated pain can affect patients' life quality. Currently regional nerve blocks are frequently used as a part of multimodal analgesia. Erector spina plane block (ESPB) is a recently defined interfascial plane block. As a result of ultrasound (USG) guided local anesthetic drug injection into the fascial plane between erector spina muscle and vertebral transverse process, multisegmental analgesia provided by spreading to the both ventral and dorsal branches of the spinal nerve roots in cranio-caudal plane with a single injection. The primary aim of this study was to evaluate the effects of bilateral ESPB on postoperative pain, using the visual analog scale (VAS) in patients delivered by CS under spinal anesthesia. The secondary aims of the study are to evaluate the effects of ESPB on analgesic drug use and patient satisfaction in the postoperative period.

116 pregnants, aged between 18-45 years, delivered by CS from May 2020 to June 2021 included the prospective, randomised, single centre study. Exclusion criteria were age under 18 years, over 45 years, body mass index (BMI) over 35 kg/m2, ASA status over III, multiple pregnancy, preeclampsia, bleeding diathesis, opioid use and allergy to drugs to be used in the study. Spinal anesthesia was administered with 0.5% bupivacaine and fentanyl 12.5mcg at the level of L4-5 interspace with 26G quincke spinal needle in the sitting position. At the end of the surgery, in ESPB group, patients were given a sitting position with the help of 2 people for USG-guided ESPB. The high-frequency linear USG probe was placed in the midline at T12 level, after the spinous process visualized, the transverse process was visualized by moving probe 3-4cm laterally. After confirming the location of the needle tip with 1-2ml hydrodissection, 10 ml bupivacaine + 10 ml salin was applied both right and left sides. At the postoperative 2, 4, 6, 12 and 24th hours, patients' rest, cough, movement, low back and headache VAS values, analgesic drug use, first analgesic use time and satisfaction were evaluated. ESPB spread level was evaluated with pin-prick at the 4-6th hours. The SPSS 11.5 program was used for statistical analysis.

Inclusion Criteria:

• between 18-45 years, pregnants delivered by CS from May 2020 to June 2021

Exclusion Criteria:

• age under 18 years, over 45 years, body mass index (BMI) over 35 kg/m2, ASA status over III, multiple pregnancy, preeclampsia, bleeding diathesis, opioid use and allergy to drugs to be used in the study