Systemic ropivacaine diminishes pain sensitization processes: a randomized, double-blinded, placebo-controlled, crossover study in healthy volunteers

Erector spinae plane versus fascia iliaca block after total hip arthroplasty: a randomized clinical trial comparing analgesic effectiveness and motor block

BACKGROUND

Ultrasound-guided supra-inguinal fascia iliaca block (FIB) provides effective analgesia after total hip arthroplasty (THA) but is complicated by high rates of motor block. The erector spinae plane block (ESPB) is a promising motor-sparing technique. In this study, we tested the analgesic superiority of the FIB over ESPB and associated motor impairment.

METHODS

In this randomized, observer-blinded clinical trial, patients scheduled for THA under spinal anesthesia were randomly assigned to preoperatively receive either the ultrasound-guided FIB or ESPB. The primary outcome was morphine consumption 24 h after surgery. The secondary outcomes were pain scores, assessment of sensory and motor block, incidence of postoperative nausea and vomiting and other complications, and development of chronic post-surgical pain.

RESULTS

A total of 60 patients completed the study. No statistically significant differences in morphine consumption at 24 h (P = 0.676) or pain scores were seen at any time point. The FIB produced more reliable sensory block in the femoral nerve (P = 0.001) and lateral femoral cutaneous nerve (P = 0.018) distributions. However, quadriceps motor strength was better preserved in the ESPB group than in the FIB group (P = 0.002). No differences in hip adduction motor strength (P = 0.253), side effects, or incidence of chronic pain were seen between the groups.

CONCLUSIONS

ESPBs may be a promising alternative to FIBs for postoperative analgesia after THA. The ESPB and FIB offer similar opioid-sparing benefits in the first 24 h after surgery; however, ESPBs result in less quadriceps motor impairment.

Effect of ropivacaine on peripheral neuropathy in streptozocin diabetes-induced rats through TRPV1-CGRP pathway

Objective To determine the effect of ropivacaine on peripheral neuropathy in diabetic rats and its possible mechanism.

Methods Forty-eight Sprague–Dawley rats were randomly divided into six groups: nondiabetic control group, nondiabetic group A (0.25% ropivacaine), nondiabetic group B (0.75% ropivacaine), diabetic control group (diabetic peripheral neuropathy (DPN) +artificial cerebrospinal fluid), diabetic group A (DPN+0.25% ropivacaine), and diabetic group B (DPN + 0.75% ropivacaine), with eight rats in each group. Within an hour of the last administration, the sciatic motor nerve conduction velocity (MNCV) of each group was measured, and the morphological changes of rat sciatic nerve were observed by HE, Weil’s staining and electron microscopy. The expression of transient receptor potential vanilloid (TRPV1) in the spinal cord dorsal horn of rats was analyzed by immunohistochemistry, and the expression of Calcitonin gene-related peptide (CGRP) protein in the spinal cord was analyzed by Western blot.

Results Compared with the nondiabetic control group, elevated blood glucose, decreased weight and reduced average mechanical withdrawal threshold (MWT), additionally, the sciatic nerves showed significantly slowed conduction velocity (both P<0.001) and damaged pathological structure, the expression of TRPV1 and CGRP were decreased (both P<0.001) in the diabetic groups. Compared with the diabetic control group, down-regulation of TRPV1 and CGRP in spinal cord was significant for the diabetic groups A and B treated with 0.25 and 0.75% ropivacaine, the higher concentration of ropivacaine correlated with a greater change.

Conclusion Ropivacaine can significantly block sciatic nerve conduction velocity in DPN rats in a concentration-dependent manner, which may be related to the expression of the TRPV1-CGRP pathway.

Intraperitoneal ropivacaine and early postoperative pain and postsurgical outcomes after laparoscopic herniorrhaphy in toddlers: a randomized clinical trial

BACKGROUND

Postoperative pain can cause physiological distress, postoperative complications, and extended lengths of hospitalized stay. In children, management of postoperative pain is still recognized as being inadequate.

OBJECTIVE

The aim of this trial was to investigate the effects of intraperitoneal ropivacaine on postoperative pain, and recovery of bowel function and emetic events after laparoscopic herniorrhaphy in toddlers.

METHODS

Seventy-six children aged from 9 months to 3 years were recruited between August 2013 and June 2014 at Tongji Hospital and randomly assigned into two groups. One group received intraperitoneal ropivacaine right before surgery and the control group received intraperitoneal saline. A standard combined general anesthesia procedure was performed under regular monitoring. Postoperative pain was assessed by the FLACC scale. Postoperative analgesic consumption, time to flatus, time to first stool, and postoperative emetic events were also recorded.

RESULTS

When compared with the control group, children who received intraperitoneal ropivacaine experienced less pain 0-4 h after surgery [P < 0.001, difference in median FLACC (95% CI) for 2 h time point is 2.00 (0.87-3.13), for 4 h time point is 1.00 (0.55-1.45)]. In addition, the number of toddlers who received analgesia 0-24 h after surgery in the ropivacaine group was lower than that in the control group [P < 0.001, difference in proportions (95% CI) is 0.575 (0.3865-0.7638)]. Compared with the control group, time to flatus in ropivacaine group was also much shorter [21.1 h vs 16.7 h, P = 0.04, difference in mean (95% CI) is 4.4 (1.49-7.28)], and the time to first stool after surgery was earlier in the ropivacaine group [30.7 h vs 25.6 h, P = 0.003, difference in mean (95% CI) is 5.1 (1.78-8.45)]. Furthermore, the incidence of emetic events in the ropivacaine group was significantly lower than the control group [32.4% vs 11.1%, P = 0.03, difference in proportions (95% CI) is 0.212 (0.0246-0.4002)].

CONCLUSION

The present results indicate that intraperitoneal ropivacaine reduces early postoperative pain and improves recovery after laparoscopic herniorrhaphy in toddlers. Therefore, IPLA is a good stratagem for postoperative pain management after laparoscopic surgery in toddlers.