Thoracic Paravertebral Nerve Block with Ropivacaine and Adjuvant Dexmedetomidine Produced Longer Analgesia in Patients Undergoing Video-Assisted Thoracoscopic Lobectomy: A Randomized Trial

Effect of dexmedetomidine on postoperative nausea and vomiting in female patients undergoing radical thoracoscopic lung cancer resection

Introduction: Postoperative nausea and vomiting (PONV) is a prevalent postsurgical complication. The objective of our study was to compare the effect of different doses of dexmedetomidine on PONV in female patients undergoing radical thoracoscopic lung cancer resection. Methods: A total of 164 female patients undergoing elective thoracoscopic radical lung cancer surgery were enrolled and assigned to one of four groups. Patients received 0.2 μg/kg/h, 0.4 μg/kg/h, 0.8 μg/kg/h dexmedetomidine and normal saline in the Dex1, Dex2, Dex3 and Control groups, respectively. The primary outcome was the incidence of PONV during 48 h postoperatively. The second outcomes included the incidence of PONV and postoperative vomiting (POV) at four time points postoperatively (T1: PACU retention period; T2: PACU discharge to postoperative 12 h; T3: postoperative 12 h-postoperative 24 h; T4: postoperative 24 h-postoperative 48 h), the area under the curve of PONV grade (PONVAUC), PONV grade, POV grade and other postoperative recovery indicators. Results: The incidence of PONV differed among the four groups. The Dex2 group (29.27%) was lower than that in the Dex1 group (61.90%) and Control group (72.50%). The incidence of PONV at T2 in the Dex1 group (11.90%) and Dex2 group (9.76%) was lower than that in the Control group (42.50%). The incidence of PONV at T3 in the Dex2 group (29.27%) was lower than that in the Dex1 group (61.90%) and Control group (62.50%). The PONVAUC was lower in the Dex2 group than in the Control group. The incidence of POV at T3 in the Dex2 and Dex3 groups was lower than that in the Control group. The consumption of remifentanil, norepinephrine, PACU dwell time, VAS scores, postoperative PCA press frequency, and the time for the first postoperative oral intake were different among the four groups. The regression model shows that the Dex2 group is a protective factor for PONV. Conclusion: Dexmedetomidine can reduce the incidence of PONV and accelerate postoperative recovery in female patients undergoing radical thoracoscopic lung cancer resection. Compared with the other two dosages, 0.4 μg/kg/h dexmedetomidine is preferable. Clinical Trial Registration: chictr.org.cn, identifier ChiCTR2300071831.

Effect of ultrasound-guided femoral nerve block with dexmedetomidine and ropivacaine on postoperative analgesia in patients undergoing total knee arthroplasty: a randomized controlled trial

Background

Dexmedetomidine, a potent and highly selective α2-adrenoreceptor agonist, has become a popular adjuvant to local anesthetics. This study was designed to investigate the effect of dexmedetomidine with ropivacaine for femoral nerve block on postoperative analgesia after total knee arthroplasty.

Methods

Forty-six patients after total knee arthroplasty received ultrasound-guided femoral nerve block with either 0.3% ropivacaine alone (group R) or 0.3% ropivacaine with 0.5 μg/kg dexmedetomidine (group RD). Total 24-h sufentanil consumption, visual analogue scale (VAS) pain scores, frequency of patient-controlled analgesia (PCA) pressed, Ramsay sedation score, the incidence of bradycardia and hypotension, and incidence of postoperative nausea and vomiting (PONV) were recorded.

Results

Compared to group R, the total 24-h sufentanil consumption was significantly reduced (110.76 ± 11.56 vs. 99.09 ± 13.31; P<0.05), the VAS scores were lower at 10 and 12 h postoperatively [3(2-3) vs. 2(1-2) and 3(2-3) vs. 2(1-3), respectively; P<0.05], the frequency of PCA pressed was lower at 8-12 and 12-16-h time intervals [(5(3-6) vs. 2(1-3) and 4(3-4) vs. 2(1-3), respectively; P<0.05]. However, there were no differences in Ramsay's sedation score and the incidence of PONV. Also, no patient experienced bradycardia and hypotension.

Conclusions

0.5 μg/kg dexmedetomidine with 0.3% ropivacaine for femoral nerve block significantly decreased the total 24-h sufentanil consumption, prolonged and enhanced the analgesic efficacy of ropivacaine, without clinically relevant cardiovascular depression or over-sedation in patients undergoing total knee arthroplasty.

Effects of Subcostal Anterior Quadratus Lumborum Block with and without Dexmedetomidine on Postoperative Rehabilitation in Patients Undergoing Laparoscopic Renal Surgery: A Prospective Double-Blinded Randomized Controlled Study

Background

The combination of different anesthesia techniques or adjuvant drugs can relieve the stress response to surgery, reduce adverse reactions and improve the clinical outcome. We investigated the effects of subcostal anterior quadratus lumborum block (SQLB) with and without dexmedetomidine (DEX) on postoperative rehabilitation for laparoscopic renal surgery (LRS).

Methods

We included 90 patients in this single-center study. All were scheduled for elective laparoscopic radical or partial nephrectomy under general anesthesia (GA). We randomly and evenly assigned them to three groups: Group GA (GA alone), Group QG (SQLB with 30 mL of 0.25% ropivacaine and GA), and Group DQG (SQLB with 30 mL of 0.25% ropivacaine plus 1 μg/kg DEX and GA). The primary outcomes were serum creatinine (Cr) and blood urea nitrogen (BUN) levels; the secondary outcomes included the average numeric rating scale (NRS) scores at rest and during activity within 48 h postoperatively; perioperative opioid consumption; the time to first ambulation, exhaust, and fluid intake, and postoperative adverse reactions.

Results

The serum Cr and BUN levels in Group DQG decreased significantly compared with Group GA (P < 0.05). The average NRS scores in Group DQG were significantly lower than other two groups (P < 0.05). Furthermore, the indexes reduced significantly in Group QG compared with Group GA (P < 0.05). Groups DQG and QG had lower consumption of opioid compared with Group GA (P < 0.05). The recovery indicators in Groups DQG and QG were higher quality than Group GA (P < 0.05). The incidences of adverse reactions in Group DQG was significantly lower than the other groups (P < 0.05).

Conclusion

SQLB with and without DEX could attenuate postoperative pain, reduce opioids requirement and side effects, as well as facilitate postoperative early rehabilitation. More interesting, SQLB with DEX could confer kidney protection.

Clinical Trial Registration Number

The Chinese Clinical Trial Registry (ChiCTR2200061554).

Perineural dexmedetomidine in femoral nerve blocks increases the duration of postoperative analgesia for anterolateral thigh flap donor sites in patients with oral cancer

Although the duration of analgesia provided by a single-shot nerve block is limited, perineural dexmedetomidine significantly enhances nerve blocks during extremity surgery. This study aimed to investigate the role of dexmedetomidine added to ropivacaine in femoral nerve blocks for postoperative analgesia of the anterolateral thigh (ALT) flap donor site in patients with oral cancer. Fifty-two participants scheduled for maxillofacial tumor resection and reconstruction using an anterolateral thigh flap were randomly allocated to either the Ropi group (femoral nerve block with ropivacaine) or the Ropi + Dex group (femoral nerve block with ropivacaine plus dexmedetomidine). The primary outcome was the duration of the sensory block, while the secondary outcomes were 24 h postoperative sufentanil use, number of patients using rescue analgesics, vital signs, postoperative pain score, incidence of agitation, and presence of adverse effects. Dexmedetomidine plus ropivacaine significantly prolonged the duration of sensory block compared with ropivacaine alone (10.4 ± 0.9 h vs 14.0 ± 1.3 h; P < 0.001). Age was positively correlated with increased duration of sensory block (r = 0.300; P = 0.033). Postoperative pain scores at the donor sites were lower in the Ropi + Dex group than in the Ropi group, at 12 h after surgery (P < 0.001). Although there were no statistically significant differences in the incidence of bradycardia between the two groups, four patients treated with dexmedetomidine experienced episodes of bradycardia. Perineural dexmedetomidine prolonged the duration of femoral nerve block and reduced postoperative pain scores at the ALT flap donor sites in patients with oral cancer.

Dexmedetomidine as an Adjuvant in Peripheral Nerve Block

Peripheral nerve block technology is important to balanced anesthesia technology. It can effectively reduce opioid usage. It is the key to enhance clinical rehabilitation as an important part of the multimodal analgesia scheme. The emergence of ultrasound technology has accelerated peripheral nerve block technology development. It can directly observe the nerve shape, surrounding tissue, and diffusion path of drugs. It can also reduce the dosage of local anesthetics by improving positioning accuracy while enhancing the block's efficacy. Dexmedetomidine is a highly selective drug α₂-adrenergic receptor agonist. Dexmedetomidine has the characteristics of sedation, analgesia, anti-anxiety, inhibition of sympathetic activity, mild respiratory inhibition, and stable hemodynamics. Numerous studies have revealed that dexmedetomidine in peripheral nerve blocks can shorten the onset time of anesthesia and prolong the time of sensory and motor nerve blocks. Although dexmedetomidine was approved by the European Drug Administration for sedation and analgesia in 2017, it has not yet been approved by the US Food and Drug Administration (FDA). It is used as a non-label drug as an adjuvant. Therefore, the risk-benefit ratio must be evaluated when using these drugs as adjuvants. This review explains the pharmacology and mechanism of dexmedetomidine, the effect of dexmedetomidine on various peripheral nerve block as an adjuvant, and compare it with other types of adjuvants. We summarized and reviewed the application progress of dexmedetomidine as an adjuvant in nerve block and look forward to its future research direction.

Evidence basis for using dexmedetomidine to enhance the quality of paravertebral block: A systematic review and meta-analysis of randomized controlled trials

Background: Dexmedetomidine is considered an adjunct to local anaesthesia (LA) to prolong peripheral nerve block time. However, the results from a previous meta-analysis were not sufficient to support its use in paravertebral block (PVB). Therefore, we performed an updated meta-analysis to evaluate the efficacy of dexmedetomidine combined with LA in PVB.

Methods: We performed an electronic database search from the date of establishment to April 2022. Randomized controlled trials (RCTs) investigating the combination of dexmedetomidine and LA compared with LA alone for PVB in adult patients were included. Postoperative pain scores, analgesic consumption, and adverse reactions were analyzed.

Results: We identified 12 trials (701 patients) and found that the application of dexmedetomidine as a PVB adjunct reduced the postoperative pain severity of patients 12 and 24 h after surgery compared to a control group. Expressed as mean difference (MD) (95% CI), the results were −1.03 (−1.18, −0.88) (p < 0.00001, I² = 79%) for 12 h and −1.08 (−1.24, −0.92) (p < 0.00001, I² = 72%) for 24 h. Dexmedetomidine prolonged the duration of analgesia by at least 173.27 min (115.61, 230.93) (p < 0.00001, I² = 81%) and reduced postoperative oral morphine consumption by 18.01 mg (−22.10, 13.92) (p < 0.00001, I² = 19%). We also found no statistically significant differences in hemodynamic complications between the two groups. According to the GRADE system, we found that the level of evidence for postoperative pain scores at 12 and 24 h was rated as moderate.

Conclusion: Our study shows that dexmedetomidine as an adjunct to LA improves the postoperative pain severity of patients after surgery and prolongs the duration of analgesia in PVB without increasing the incidence of adverse effects.