Ultrasound-guided Thoracic Mid-Point Transverse Process to Pleural Block Versus Thoracic Paravertebral Block for Post Thoracotomy Analgesia

A posterolateral thoracotomy provides good access to the lung, middle and posterior mediastinum, hilum, endothoracic trachea, and endothoracic esophagus, while also allowing for safe control of pulmonary blood vessels during pulmonary resection. There are two potential disadvantages to the posterolateral thoracotomy; they are that it is painful aid that it may disturb the respiratory mechanics through division of respiratory muscles and decreased mobility of the chest wall. Respiratory distress may ensue because of chest muscular contraction, which hinders the capacity of the lungs to expand and contract. Thoracic spine and chest wall pain is less prevalent than lumbar or cervical area pain, but it has been reported to affect 13% to 15% of the total population. Moreover, persistent thoracic spine and chest wall pain could impair activities of daily living and cause decline in the quality of life Many patients may develop post-operative thoracotomy pain syndrome defined as "pain that recurs or continues along a thoracotomy scar at least 2 months after the surgery" because of insufficient postoperative pain treatment . In lung surgery, acute postoperative pain prevents deep breathing and coughing, with a strong relationship between pain and respiratory problems such as pneumonia and atelectasis Multimodal pain management has been suggested, including opioids with their known side effect .

Though Thoracic epidural analgesia was considered as the gold standard for post-thoracotomy pain management, it is not used nowadays for thoracotomy pain because it is associated with high potential risks of dural puncture, nerve lesions, epidural hematoma, and hypotension .

Paravertebral block has gained more popularity than other regional analgesic techniques including caudal and epidural for perioperative analgesia in thoracic surgery. Thoracic paravertebral block provides adequate postoperative analgesia with favorable adverse effects.

The use of thoracic Paravertebral block in thoracic surgery is associated with decreased pain severity and opioid consumption in both adults and children. TPVB alone has previously been compared with GA alone, much of the literature is heterogeneous and includes landmark techniques at multiple thoracic levels which are time consuming, uncomfortable, and expose the patient to risk with each needle pass. A block from T1-T6 is required for most breast cancer surgeries.

Recently, a newer technique "midpoint transverse process to pleura" block has been described in which the tip of the needle is placed at the midpoint between the transverse process and pleura. Injections of local analgesia are made between the transverse process and the pleura. The local analgesia travels via the fenestrations in the superior costotransverse ligament at the injection level and frequently to adjacent levels, reaching the dorsal and ventral rami in the paravertebral region.

The aim of the study is to compare the analgesic efficacy and safety of midpoint transverse process to pleura to pleural block versus Paravertebral block for post thoracic surgery analgesia.