The Analgesic Efficacy of Erector Spinae Block in Comparison to Thoracic Epidural Anesthesia in Patients Having Transthoracic Oesophygeal Surgical Procedures

The patients will randomised into 2 groups. There are 2 groups of patients: TEA combined with GA or bilateral erector spinae block combined with G. In TEA group, patients will receive TEA, an epidural catheter will be placed at the T7-8 interspace after positioning of the patient in the sitting position then standard technique of application will be applied, then a test dose consists of 3 ml of 1.5% preservative free lidocaine with 1:200,000 epinephrine will be injected followed by 5-6 ml of bupivacaine 0.25%. Anaesthesia will be standardised. A left-sided, double-lumen thoracostomy tube will be inserted and confirmed by bronchofiberoscopy. In the TEA group, an additional 4-5mL epidural doses of bupivacaine 0.25% will be administered at 1 h intervals. In the second group, patients will receive bilateral ESP block which will be performed as follows. The patient will be placed in a lateral position and a high-frequency linear ultrasound transducer (GE LOGIQe, Wauwatosa, Wisconsin) will be placed in a longitudinal orientation 3 cm lateral to the T7 spinous process. Three muscles will be identified superficial to the hyperechoic transverse process shadow as follows: trapezius, rhomboid major, and erector spinae. An 8-cm 22-gauge block needle (EchoStim; Benlan Inc, Oakville, Canada) will be inserted in a cephalad-to-caudad direction until the tip lay in the interfascial plane between rhomboid major and erector spinae muscles, as evidenced by visualization of local anesthetic spreading in a linear pattern between erector spinae and the bony acoustic shadows of the transverse processes. A total of 20 mL of 0.25% bupivacaine will be injected then it will be repeated on the other side and preformed in the same way without changing the position of the patient to achieve sensory block T5-T10 .

Hemodynamics as heart rate, arterial blood pressure, central venous pressure and oxygen saturation will be monitored intraoperatively. The heart rate and arterial blood pressure will be maintained within 20% of the preoperative values.

At the end of the procedure, in both groups, anesthesia will be discontinued and neuromuscular blockade will be antagonized with neostigmine, intravenous (0.05 mg/kg) and atropine intravenous (0.03 mg/kg) at appropriate doses.

The patients will be transported postoperatively to the intensive care unit. if VAS > 5 , Patient-controlled analgesia using elastomeric pump will be established with IV doses of morphine in the erector group (basal rate about 0.5mg/h to 1 mg/h and bolus dose of 2 mg , 300 mL maximum dose) and epidural analgesia in the TEA group (top up doses of about 4 ml of bupivacaine 0.125% + morphine 20 μg/mL, bolus doses 2 mL to 3 mL, 300 ml maximum dose). The patients will be monitored in the postanaesthesia care unit (PACU)