Lumbar ESPB in Hip Replacement Surgery

Before the beginning of surgery, all patients will be anesthetized with 0.5 % hyperbaric bupivacaine (Marcaine Heavy), 1.5 - 2.5 mL solution. A pencil point spinal needle will be used.

Investigators will perform the lumbar ESPB under ultrasound control at the L3 level on the ipsilateral site of the surgery. After dissection with 0.9 NaCl, we will leave a catheter in the ESP. Then, we used 0.25% bupivacaine with epinephrine (5mcg/mL), 0.4 mL per kg, up to 40 mL.

After identifying the epidural space and spinal anesthesia (combined technique), a catheter will be placed in the epidural space. Investigators will give an epidural catheter a test dose of 2% lidocaine (2 mL). At the end of the surgery, the patient will receive 5 mL of a mixture containing 0.1% bupivacaine with fentanyl (2 mcg/mL).

Each participant will receive a pump with oxycodone (1mg/ml) using a patient-controlled analgesia (PCA) technique, a bolus of 1 mL, and a lockout of 5 minutes for the first postoperative day.

Investigators will measure the time the patient took to rise from a chair, walk three meters, turn around 180 degrees, walk back to the chair, and sit down while rotating 180 degrees. We will assess the patient before the surgery and 24 and 48 hours after hip replacement.

The Neuropathic Pain Symptom Inventory (0-100; 0 denotes no pain, 100 the most severe pain) will be evaluated before the surgery and three and six months following the procedure.

A physiotherapist will use the six-grade Lovett scale to measure muscle strength, in which 0 denotes no muscle contractility, and 5 denotes the complete range of motion against gravity, with full resistance. We will test this before the surgery, 24 and 48 hours after the operation.

Investigators will measure pain intensity with VAS (0-10; 0 denotes no pain, 10 maximal pain) before and after the surgery. Pain will be evaluated at rest and upon the activity.

Investigators will assess the quality of recovery with QoR-40 a day after the surgery, a month, and three months following the procedure. The minimal score is 40, and the maximal is 200. The higher the result, the better the quality of recovery is.

A physiotherapist will evaluate the patient's ability to sit, stand upright, and walk at planned times.