A comparative study of respiratory effects of erector spinae plane block versus paravertebral plane block for women undergoing modified radical mastectomy

BackgroundInadequate acute postoperative pain control after modified radical mastectomy (MRM) can compromise pulmonary function. This work aimed to assess the postoperative pulmonary effects of a single-shot thoracic paravertebral block (TPVB) and erector spinae plane block (ESPB) in female patients undergoing MRM.MethodsThis prospective, randomized comparative trial was conducted on 40 female American Society of Anesthesiologists (ASA) II-III, aged 18 to 50 years undergoing MRM under general anesthesia (GA). Patients were divided into two equal groups (20 in each group): Group I received ESPB and Group II received TPVB. Each group received a single shot with 20 ml volume of 0.5% bupivacaine.ResultsRespiratory function tests showed a comparable decrease in forced vital capacity (FVC) and forced expiratory volume (FEV1) from the baseline in the two groups. Group I had a lower FEV1/FVC ratio than Group II after 6 h. Both groups were comparable regarding duration for the first postoperative analgesic request (P value = 0.088), comparable postoperative analgesic consumption (P value = 0.855), and stable hemodynamics with no reported side effects.ConclusionBoth ultrasound guided ESPB and TPVB appeared to be effective in preserving pulmonary function during the first 24 h after MRM. This is thought to be due to their pain-relieving effects, as evidenced by decreased postoperative analgesic consumption and prolonged time to postoperative analgesic request in both groups.ClinicalTrials.gov IDNCT03614091 registration date on 13/7/2018.