Comparison of the analgesic effect of ultrasound-guided paravertebral block and ultrasound-guided retrolaminar block in Uniportal video-assisted Thoracoscopic surgery: a prospective, randomized study

Abstract

Background: The optimal modality for postoperative analgesia after uniportal video-assisted thoracoscopic surgery (UVATS) for the treatment of lung cancer has not yet been determined. Both ultrasound-guided paravertebral block (PVB) and retrolaminar block (RLB) have been reported to be successful in providing analgesia after UVATS. However, which block technique provides superior analgesia after UVATS is still unclear. This randomized study was designed to compare the postoperative analgesic effects and adverse events associated with ultrasound-guided PVB and RLB after UVATS.

Methods: Sixty patients with lung cancer were randomized to undergo ultrasound-guided PVB (group P) or ultrasound-guided RLB (group R). In group P, 30 mL of 0.5% ropivacaine was injected at the T3 and T5 levels via ultrasound-guided PVB (15 mL at each level on the operative side). In group R, 30 mL of 0.5% ropivacaine was injected at the T3 and T5 levels via ultrasound-guided RLB (15 mL at each level on the operative side). The primary outcome was the numerical rating scale (NRS) score within 48 h after surgery. The secondary outcomes were total postoperative sufentanil consumption, time to first analgesic request and adverse events.

Results: At 3, 6, 12, 24, 36 and 48 h postoperatively, the NRS score at rest in group P was lower than that in group R (p < 0.05). At 3, 6, 12, 24 and 36 h postoperatively, the NRS score while coughing in group P was lower than that in group R (p < 0.05). The total postoperative sufentanil consumption in group P was significantly lower than that in group R (p < 0.001). Additionally, the time to first analgesic request was longer in group R than in group P (p < 0.0001). The incidence of nausea in group R was higher than that in group P (p < 0.05).

Conclusions: In patients with lung cancer undergoing UVATS, ultrasound-guided PVB with 0.5% ropivacaine provides better analgesia and results in less nausea than ultrasound-guided RLB. Compared with ultrasound-guided RLB, ultrasound-guided PVB seems to be a better technique for analgesia in UVATS.

Trial registration: The name of this study is the Effect And Mechanism Of Ultrasound-guided Multimodal Regional Nerve Block On Acute And Chronic Pain After Thoracic Surgery. This study was registered in the Chinese Clinical Trial Registry ( ChiCTR2100044060 ). The date of registration was March 9, 2021.

Keywords: Adverse events; Lung cancer; Pain; Ultrasound-guided paravertebral block; Ultrasound-guided retrolaminar block; Uniportal video-assisted thoracoscopic surgery.

Fig. 1

Patient inclusion and exclusion process. PCIA, patient-controlled intravenous analgesia

Fig. 2

The T3 and T5 spinal segments where ultrasound-guided PVB or RLB was to be performed

Fig. 3

Ultrasound images of PVB and RLB. A shows an ultrasound image of the paravertebral space before the injection of ropivacaine. B shows that the paravertebral space widened after the injection of 15 ml of ropivacaine. C shows an ultrasound image of the thoracic lamina before the injection of ropivacaine. D shows the hypoechoic area formed by the injection of ropivacaine above the lamina

Fig. 4

The 5-cm-long surgical incision was made in the fourth intercostal space at the anterior axillary line (A). B shows the surgical field of thoracoscopic lobectomy. A chest drain was placed at the edge of the incision at the end of the surgery (C). D shows the chest drainage system

Fig. 5

Postoperative pain severity NRS score at rest (in cm) at 3, 6, 12, 24, 36 and 48 h postoperatively. P, paravertebral block; R, retrolaminar block; NRS, numerical rating scale. ^*P < 0.05

Fig. 6

Postoperative pain severity NRS score during coughing (in cm) at 3, 6, 12, 24, 36 and 48 h postoperatively. P, paravertebral block; R, retrolaminar block; NRS, numerical rating scale. ^*P < 0.05

Fig. 7

A shows the mean arterial pressure (MAP) changes at different times in each group. In both groups, the MAP showed significant changes over time, with ^*P < 0.001. B shows the heart rate (HR) changes at different times in each group. In both groups, the HR showed significant changes over time, with ^*P < 0.05. P, paravertebral block; R, retrolaminar block