TLIP Block and ESP Block For Perioperative Analgesia In Patients With Lumbar Spine Fusion Surgery

Background: Pain relief for lumbar spine surgery is being updated to help improve the quality of post-operative recovery, especially ultrasound-guided pain relief anesthesia methods, including two anesthesia methods. Thoracolumbar interfascial plane block (TLIP block) and erector spinae plane block (ESP block) are increasingly commonly applied. Objective: compare the pain relief effectiveness of TLIP block with ESP block for lumbar spine surgery.

Methods: Randomized prospective intervention study conducted at Hanoi Medical University Hospital from October 2021 to October 2022 including 100 lumbar spine surgery patients randomly divided into three groups: group control, TLIP group and ESP group. Outcomes regarding perioperative pain score (ANIm, VAS), the effectiveness of 2 ultrasound-guided methods, the complications and the side effects were recorded.

* All research patients were divided into 3 groups by random drawing: control group, TLIP group and ESP group.
* TLIP group: patients were anesthetized before surgery using TLIP lumbar block (L3) under ultrasound with 20ml of ropivacaine 0.25% anesthetic on each side. After that, the patient was given endotracheal anesthesia for surgery.
* ESP group: patients were anesthetized before surgery with lumbar (L3) ESP block method under ultrasound with 20ml of Ropivacaine 0.25% anesthetic on each side. After that, the patient was given endotracheal anesthesia for surgery.
* Control group: patients received regular endotracheal anesthesia, then the incision was anesthetized with 15ml of 1% lidocaine mixed with 1/200,000 adrenaline on each side before surgery.
* Anesthesia and monitoring process: all patients in all 3 groups were anesthetized using general anesthesia:

  * Install monitoring to monitor pulse parameters, blood pressure, SpO2, EtCO2.
  * Install an Analgesia Nociception Index (ANI) meter and monitor the ANI index continuously during surgery. Monitor ANI monitor V2 during surgery, maintain ANIm within the range of 50-70.
  * Induction of anesthesia: fentanyl 2mcg/kg slow intravenous injection, wait 3 minutes then inject propofol 2-3mg/kg, rocuronium 0.6mg/kg (when eyelid reflex is lost). Proceed with endotracheal intubation and artificial ventilation at a frequency of 12 times/minute, Vt = 6-8ml/kg, FiO2 50%, I:E = 1:2, PEEP = 5cmH2O, EtCO2 = 35-45mmHg, sevoflurane Install until MAC reaches 0.8-1.
  * Maintain anesthesia with sevofluran, maintain 1 MAC.
  * Using fentanyl during surgery: when ANIm index is less than 50: 50mcg fentanyl bolus, repeat after 5 minutes until ANIm greater than 50. Record the amount of fentanyl used during surgery. Record the ANIm index at the time of the study: when skin incision (T0) and every 10 minutes until the end of surgery.
  * Release of anesthesia: Patients are extubated when they meet the criteria: awake, following orders, breathing rate 12-20 times/minute, SpO2 \> 95% with FiO2 ≤ 40%, Vt \> 5ml/kg, EtCO2 \< 45 mmHg , good cough and swallow reflex and TOF ≥ 90%. After extubation, monitor the patient, record pulse index, blood pressure and VAS score and transfer the patient to the hospital room if it reaches 10/10 points according to Aldrete.
* Pain relief: both groups received paracetamol 1g and ketorolac 30mg at the end of skin closure and every 8 hours thereafter. When the patient has postoperative pain (VAS score ≥ 4), they are titrated with intravenous morphine 1mg/time every 10 minutes until reaching a VAS score \< 4. At the same time, an intravenous morphine pain relief machine is installed. Patient controlled analgesia (PCA) with bolus setting 1ml = 1mg, lockout time 10 minutes, maximum dose 20mg/4 hours, no background infusion dose.

Eligibility Criteria:
Inclusion Criteria:

* American Society of Anesthesiologists (ASA) physical status I-III.
* Patients had lumbar spinal fusion surgery.

Exclusion Criteria:

* The patient does not agree to participate in the study.
* Patients with severe chronic diseases: liver failure, kidney failure, heart failure, arrhythmia, neuromuscular disease.
* Patients are using drugs that affect the autonomic nervous system such as beta blockers, parasympathomimetic drugs.
* history of mental disorders, difficulty in communication.
* Patients with acute lumbar spine injury or a history of lumbar spine surgery, injections, abscesses, and lumbar infections.