The effects of body mass index on postoperative pain in patients undergoing thoracic paravertebral block after video-assisted thoracoscopic surgery: A retrospective analysis

Abstract

Aim: Postoperative pain is an important problem in patients undergoing video-assisted thoracic surgery (VATS). Thoracic paravertebral block (TPVB) is among the commonly used techniques for pain control after VATS. Despite the analgesic methods applied, the desired level of pain control can not be achieved in all patients. Therefore, clinicians and researchers are interested in factors affecting postoperative pain. One factor is the relationship between postoperative pain and body mass index (BMI). Although it has been reported that acute or chronic pain is more common in the general population with a BMI, the relationship between postoperative pain and BMI is still controversial. This study aims to investigate the effects of BMI on postoperative pain in patients who underwent TPVB in the treatment of pain after VATS.
 Material and Method: Patients who had elective VATS and TPVB were included in the study. Patients who underwent TPVB with ultrasonography (USG) and postoperative intravenous (iv) morphine patient-control-analgesia (PCA) for postoperative analgesia were divided into three groups according to BMI. Group-I BMI: 18-24.99 kg/m2, Group-II BMI: 25-29.9 kg/m2, Group-III BMI: 30-40 kg/m2.
 Results: 146 patients were included in the study. There was no significant difference between the postoperative 30th minute, 1st hour, 6th hour, 12th hour, and 24th-hour VAS values of the patients in Group-I, Group-II, and Group-III. There was no statistically significant difference in terms of morphine consumption, additional analgesic requirement, and complications in all three groups.
 Conclusion: It was determined that there was no relationship between BMI and postoperative pain scores in the first 24 hours in patients who underwent TPVB after VATS. In addition, it was determined that postoperative morphine consumption and additional analgesic needs were not associated with BMI. Effective pain control can be achieved in all patients, regardless of BMI, with effective peripheral nerve blocks and analgesics using practical imaging techniques such as USG.