Discussion
postoperative pain, coagulation disorders, nausea and vomiting, nausea and dizziness, pain, hypotension, respiratory depression
COAGULATION DISORDERS, CHRONIC POSTTHORACOTOMY PAIN, MORBID OBESITY, ADVERSE EVENTS, THORACIC, SECONDARY, RESPIRATORY DEPRESSION
In this study, we examined the effectiveness of ESP blocks and TEA as postoperative analgesics in patients undergoing VATS. Continuous ESP block provided inferior postoperative analgesia to TEA regarding analgesic efficacy in the immediate post-operative period following VATS, as shown by the NRS score at rest and during coughing for 48 hours postoperatively. Furthermore, ESP block needed more opioid consumption than the TEA group. However, the NRS score difference between groups was smaller than 2/10, and the TEA group had a greater incidence of overall adverse events than the ESP block group.Forero et alPrevious research has suggested that the ESP block may function by blocking the dorsal and ventral rami of the thoracic spinal nerves as well as sympathetic nerve fibers.Thoracic epidural analgesia and TPVB represent the gold standards for both open thoracotomy and VATS. Recently, these regional anesthetic techniques, as adjuncts to anesthesia, are considered one of the critical components in a thoracic enhanced recovery after surgery (ERAS) program because of the benefit for acute postoperative pain management.However, continuous TEA has been our institution’s 1st regional analgesic option for thoracic surgery. In addition, it could reduce chronic postthoracotomy pain and provide effective acute pain relief.The analgesic effect of the ESP block may be comparable to or less than that of a TPVB. Turhan et alAlthough ESP block patients had more morphine consumption than TEA patients (6 mg versus [vs.] 3 mg), the overall incidence of adverse events in TEA patients was higher than in ESP block patients in our study. Postoperative opioid use can increase the incidence of nausea and vomiting. However, the amount of morphine consumed in both groups was relatively low because all participants took multimodal analgesia, including regional analgesic techniques, regular parenteral analgesics, and rescue opioids. In addition, the high thoracic epidural blockade could cause hypotension and related symptoms, including nausea and dizziness. Furthermore, nausea and vomiting could be related to hyperperistalsis secondary to unopposed vagal activity after TEA.An ESP block might be a simpler and safer option to standard techniques since the key structure (the tip of the transverse process) is easily identified with ultrasound, and the needle can be inserted using the in-plane method. Additionally, the injection site is distant from the spinal cord, pleura, and major vascular structures. It may be performed at any time during the perioperative period on prone or lateral patients. Therefore, this block could provide better analgesia in patients with morbid obesity, spinal deformities, or decreased respiratory depression and could reduce the risk for patients with coagulation disorders or current anticoagulation therapy.Previous literature described spreading across 5 to 9 dermatomes when the ESP block was performed at the T5 level, and 20 mL of continuous local anesthetic infusion was administered at 8 mL/h.We used different methods to deliver local anesthetics to each group. In the ESP block group, a background PIBI with PCA was administered, whereas in the TEA group, PCA was administered continuously. The difference in the delivery method might affect the analgesic efficacy between groups. However, we expected the PIBI to result in a more extensive spread of local anesthetic and to show a better analgesic profile than continuous infusion in the ESP group. These issues have been controversial, but recently TPVB with PIBI showed a superior analgesic profile compared to continuous infusion in patients undergoing VATS.Furthermore, PIBI with TEA increased hypotension incidence, although it reduced local anesthetic consumption in patients undergoing thoracic surgery.