Transversus abdominis plane (TAP) block with levobupivacaine versus levobupivacaine with dexmedetomidine for postoperative analgesia following cesarean delivery

Long-Acting Bupivacaine for Pain Control After Cesarean Birth

OBJECTIVE

To evaluate women's postcesarean pain levels and total opioid use for standard opioid pain management compared with local anesthetic with patient-requested opioids.

DESIGN

Retrospective cohort study.

SETTING/LOCAL PROBLEM

Rural southeast Ohio. Ohio had a higher rate of opioid use disorder (1.4%) than both the regional average (0.8%) and the national average (0.7%).

PARTICIPANTS

We performed a retrospective study of 402 medical records of women who gave birth by caesarean.

INTERVENTION

Women were provided one of three types of perioperative anesthesia: routine spinal (standard of care group), wound infiltration with liposomal bupivacaine (LB INF), and transversus abdominis plane (TAP) block with liposomal bupivacaine (LB TAP).Data were collected on the amount of opioids taken postoperatively (measured as morphine milligram equivalents [MME]), pain scores, and history of opioid use.

RESULTS

The LB INF and LB TAP groups had significantly lower total and average MME per day than the standard of care group (p < .001). Pain scores for the LB INF group were lower on postoperative day (POD) 0 and POD1, whereas LB TAP pain scores were lower than standard of care pain scores on POD1 (p < .004). Women with a prior history of substance use disorders reported higher pain scores, took more total opioids. and stayed in the hospital longer regardless of type of anesthesia received (p < .001).

CONCLUSION

LB INF and LB TAP were associated with lower amounts of opioids used and with lower postcesarean pain scores compared with the standard of care.

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.

Comparative study of dexmedetomidine versus fentanyl as adjuvants to bupivacaine in ultrasound-guided transversus abdominis plane block in patients undergoing radical cystectomy: a prospective randomised study

Background

Transversus abdominis plane (TAP) block is beneficial for pain management after conducting abdominal surgery.

Objective

To compare the outcomes of dexmedetomidine and fentanyl, as adjuvants to bupivacaine, for ultrasound-guided TAP block analgesia among patients undergoing radical cystectomy for postoperative pain management.

Methods

This prospective, randomised, comparative study included a total of 60 patients, who underwent radical cystectomy. Participants were randomly divided into three categories with 20 subjects each; group B had patients who received a single shot US-guided TAP block on each side with 20 ml of 0.25% bupivacaine + 2 ml normal saline; group BF had patients who received a single shot US-guided TAP block on each side with 20 ml of 0.25% bupivacaine + 1 µg/kg fentanyl dissolved in 2 ml normal saline and group BD had patients who received a single shot US-guided TAP block on each side with 20 ml of 0.25% bupivacaine + 1 µg/kg dexmedetomidine dissolved in 2 ml normal saline.The researchers recorded the time taken for first rescue analgesia, total analgesic dose in the first 24 h after surgery, patient satisfaction, sedation score, and postoperative complications.

Results

The time taken for first rescue analgesia was significantly lengthier in group (BD) (8.90 ± 2.47) than (BF) (6.50 ± 1.43) and (B) (4.40 ± 1.05) groups. The total nalbuphine consumption, during the first 24 h, was significantly lower in (BD) (0.15 ± 0.00) group compared to (BF) (0.20 ± 0.07) and (B) (0.24 ± 0.08) groups.

Conclusion

In comparison with fentanyl, as an adjuvant to bupivacaine, dexmedetomidine was found to be associated with prolonged postoperative analgesia, less postoperative pain scores and low opioid consumption.

Trial registration

This study was registered at Clinical Trials.gov on 23 March 2020 (registration number: NCT04318158).

Efficacy of dexmedetomidine as an adjunct to ropivacaine in bilateral dual-transversus abdominis plane blocks in patients with ovarian cancer who underwent cytoreductive surgery

OBJECTIVE

We sought to evaluate the postoperative control of pain and recovery in patients with ovarian cancer who underwent cytoreductive surgery by adding dexmedetomidine to ropivacaine in bilateral dual-transversus abdominis plane (Bd-TAP) blocks.

METHODS

We enrolled 90 patients with an American Society of Anesthesiologists physical status I to III undergoing open abdominal cytoreductive surgery in this study. Patients were randomized and assigned into three groups (TAP-R, TAP-DR, or CON) of 30 participants each. All of the patients received standardized general anesthesia, and postoperative Bd-TAP blocks were performed. The TAP-R, TAP-DR, and CON groups received Bd-TAP blocks with 0.3% ropivacaine, 0.3% ropivacaine and 0.5 μg/kg of dexmedetomidine, and 0.9% normal saline, respectively. All of the patients received patient-controlled analgesia (PCA) (formula, 100 μg of sufentanil and 16 mg of ondansetron diluted with normal saline to 100 mL). Flurbiprofen axetil was used as a rescue drug if the visual analog scale (VAS) score was more than four points. The first request time for PCA bolus; the VAS scores at 0, 6, 12, 24, and 48 h after operation; and the cumulative sufentanil consumption within 24 and 48 h, respectively, were compared. Pulmonary function was evaluated preoperatively and at 24 h after the operation. The use of the rescue drug was recorded. Postoperative functional recovery, including time to stand, time to walk, time to return of bowel function, time to readiness for discharge, and postoperative complications, were recorded.

RESULTS

Median values of the first request time for PCA of the TAP-R group was significantly prolonged compared to that of the CON group (median [interquartile range], 7.3 [6.5-8.0] hours vs. 3.0 [2.3-3.5] hours) (P < .001), while the TAP-DR group has the longest request time among the three groups (median [interquartile range], 13.5 [12.4-14.5] hours) (P < .001). The VAS scores at rest and upon coughing of the TAP-R group in the first 12 h were significantly lower than those of the CON group (P < 0.05), but showed no significant difference compared to those of the TAP-DR group. The VAS scores at rest and upon coughing were lower in the TAP-DR group at each time point compared to those of the CON group (P < .05). The cumulative sufentanil consumption in the TAP-DR group was significantly lower at 48 h (P = .04) after surgery than in the CON group, while there was no significant difference compared to that in the TAP-R group (P > .05). Less rescue analgesic was required by patients in the TAP-DR group than in the CON group (P < .05). Postoperative mean measured forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity values in the TAP-DR group were significantly higher than those of the CON group (P = .009), while there was no significant difference compared to those of the TAP-R group (P = .10). There was no significantly difference in postoperative functional recovery between TAP-DR and CON group (P > 0.05).

CONCLUSION

TAP blocks can provide effective pain relief up to 12 h postoperatively without a significant improvement in postoperative pulmonary function. The addition of dexmedetomidine to ropivacaine for Bd-TAP block prolonged the first bolus time of PCA when compared to that in the TAP-R group and decreased sufentanil consumption and the need of rescue analgesia relative to in the CON group at 48 h postoperative. The procedure provided better postoperative analgesia and improved postoperative pulmonary function relative to the CON group. Our results indicate that dexmedetomidine as an adjuvant of Bd-TAP can provide effective pain relief up to 48 h.

Efficacy of regional blocks or local anaesthetic infiltration for analgesia after caesarean delivery: a network meta-analysis of randomised controlled trials

Caesarean delivery is common and can cause severe postoperative pain but injection of local anaesthetic at various sites for regional blocks or local anaesthetic infiltration may reduce this. We aimed to compare and rank these sites. We searched PubMed, Google Scholar, EMBASE and CENTRAL to June 2021 for randomised controlled trials and performed a random-effects Bayesian model network meta-analysis. The primary outcome was dose of parenteral morphine equivalents in the first 24 postoperative hours. We used surface under cumulative ranking probabilities to order techniques. We analysed 114 trials (8730 participants). The ordered mean (95% credible interval) reduction in morphine equivalents, from 34 mg with placebo, were as follows: ilio-inguinal 15 (1-32) mg; ilio-inguinal-iliohypogastric 13 (6-19) mg; transversalis fascia 11 (4-26) mg; erector spinae 11 (10-32); transverse abdominis 9 (4-13) mg; wound catheter infusion 8 (2-15) mg; quadratus lumborum 8 (1-15) mg; wound infiltration 8 (2-13) mg; and no intervention -4 (-10 to 2) mg. Ordered efficacies for injection sites were different for other relevant outcomes, including pain (to 4-6 h and to 24 h) and time to rescue analgesia: there was no single preferred route of injection. The ordered mean (95% credible interval) reduction in dynamic pain scores (0-10 scale) at 24 h compared with placebo were as follows: wound infusion 1.2 (0.2-2.1); erector spinae 1.3 (-0.5 to 3.1); quadratus lumborum 1.0 (0.1-1.8); ilio-inguinal-iliohypogastric 0.6 (-0.5 to 1.8); transverse abdominis 0.6 (-0.1 to 1.2); wound infiltration 0.5 (-0.3 to 1.3); transversalis fascia -0.8 (-3.4 to 1.9); ilio-inguinal -0.9 (-3.6 to 1.7); and no intervention -0.8 (-1.8 to 0.2). We categorised our confidence in effect sizes as low or very low.

Dexmedetomidine and levobupivacaine co-loaded, transcriptional transactivator peptide modified nanostructured lipid carriers or lipid-polymer hybrid nanoparticles, which performed better for local anesthetic therapy?

Local anesthetics (LAs) have been widely applied in clinic for regional anesthesia, postoperative analgesia, and management of acute and chronic pain. Nanostructured lipid carriers (NLCs) and lipid–polymer hybrid nanoparticles (LPNs) are reported as good choices for LA therapy. Transactivated transcriptional activator (TAT) was reported as a modifier for the topical delivery of drugs. In the present study, TAT modified, levobupivacaine (LEV) and dexmedetomidine (DEX) co-delivered NLCs (TAT-LEV&DEX-NLCs, T-L&D-N) and LPNs (TAT-LEV&DEX-LPNs, T-L&D-L) were designed and compared for the LA therapy. T-L&D-L exhibited better efficiency in improving the skin permeation, analgesic time, and pain control intensity than T-L&D-N both in vitro and in vivo. On the other side, T-L&D-N also improved the therapeutic effect of drugs to a large extent. These two systems both exhibited superiority in some respects. TAT modified LPNs are more promising platform for the long-term local anesthesia.

Analgesic efficacy of ultrasound-guided transversus abdominis plane block after cesarean delivery: A systematic review and meta-analysis

PURPOSE

The meta-analysis is aimed to further access the analgesic efficacy of ultrasound-guided transversus abdominis plane (USG-TAP) block after cesarean section (CS).

METHODS

Electronic databases were searched for eligible studies. Primary objectives were pain-related outcomes. Weighted mean differences (WMDs) or standardized mean differences (SMDs), as well as risk ratios (RRs) with 95% confidence intervals (CIs), were used to calculate estimates. Subgroup analyses were done based on whether USG-TAP blocks were performed with long-acting intrathecal opioids (ITO).

RESULTS

A total of 17 studies were included. When compared with control groups (placebo or no blocks), USG-TAP block resulted in lower cumulative opioid consumption at 6 h (WMD: -8.32; 95% CI: -14.86, -1.79), 12 h (WMD: -10.75; 95% CI: -20.93, -0.57), and 24 h (WMD: -12.71, 95% CI: -21.28, -4.14). No significant differences were demonstrated among dynamic or resting pain scores. Patients in USG-TAP groups needed longer time to request first analgesic (WMD: 3.56; 95% CI: 1.43, 5.68) and showed a lower requirement of opioid rescue analgesia for breakthrough severe pain during 24 h (RR: 0.40; 95% CI: 0.18, 0.86). Subgroup analyses showed USG-TAP blocks did not afford additional benefit in the presence of intrathecal morphine. Also, reduced need for antiemetics after CS and higher maternal satisfaction were provided by USG-TAP blocks.

CONCLUSION

USG-TAP block can provide significantly effective analgesia for patients who underwent CS in the absence of long-acting ITO and therefore are worth promoting in the setting of long-acting ITO being unfeasible.