Efficacy of local anaesthetic and steroid combination in prevention of post-herpetic neuralgia: A meta-analysis

Objective: The objective was to provide synthesized evidence on the efficacy of local anaesthetics and steroid injections for prevention and management of PHN, compared to the standard treatment using anti-viral and analgesic medications. The primary outcomes of interest were incidence of PHN and duration of neuralgic pain. Methods: Comprehensive searches were done systematically through PubMed, Scopus, Cochrane Central Register of Controlled Trials and Google scholar databases. Randomized controlled trials that compared the efficacy of local anaesthetics and steroid injections for preventing and managing PHN were included for this meta-analysis. A comprehensive search was done for papers published until 15th July 2021. Results: A total of 10 RCTs were included in the meta-analysis. In the overall pooled analyses, compared to standard care/placebo, those receiving a combination of local anaesthetic and steroid injection had 55% lower risk of PHN at 3 months from onset of rash (RR 0.45; 95% CI, 0.29; 0.70). Out of the different modes of intervention delivery i.e., intravenous, subcutaneous and nerve block, maximum beneficial effect in reducing the incidence of PHN was noted in nerve block (RR 0.55; 95% CI, 0.34, 0.89). Conclusions: The meta-analysis provides some evidence to support the use of combined local anaesthetic and steroids in reducing risk of post-herpetic neuralgia and duration of neuralgic pain in patients with herpes zoster rash. doi: https://doi.org/10.12669/pjms.38.3.5140 How to cite this:Zhang X, Wang Z, Xian Y. Efficacy of local anaesthetic and steroid combination in prevention of post-herpetic neuralgia: A meta-analysis. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.5140 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Pain control according to the periprostatic nerve block site in magnetic resonance imaging/transrectal targeted prostate biopsy

We analyzed the intensity of pain at each site of systemic prostate biopsy (SBx) and compared the intensity of pain among magnetic resonance (MRI)-targeted transrectal biopsies according to the periprostatic nerve block (PNB) site. We collected data from 229 consecutive patients who had undergone MRI-targeted biopsy. Patients were stratified into two groups according to the site of PNB (base versus base and apex PNB). Pain was quantified at the following time points: probe insertion, injection at the prostate base, injection at the prostate apex, MRI cognitive biopsy (CBx), MRI/transrectal ultrasound fusion biopsy (FBx), SBx, and 15 min after biopsy. For all biopsy methods, the average pain were significantly higher in the base PNB group than in the base and apex PNB group (CBx, p < 0.001; FBx, p = 0.015; SBx, p < 0.001). In the base and apex PNB group, FBx was significantly more painful than SBx (p = 0.024). Overall, regardless of the PNB site, pain at the anterior sites was more than that at the posterior sites in FBx (p = 0.039). Base and apex PNB provided better overall pain control than base-only PNB in all biopsy methods. In the base and apex PNB group, FBx was more painful than CBx and SBx.

The Global Publication Trend and Research Development of Nerve Block: A Visualisation Analysis Between 1997 and 2021

Background: Nerve block is used as a clinical technique for relieving pain during the surgical period as well as in postoperative analgesia and chronic pain. Although great progress has been recently made regarding nerve block techniques, there is still room for further medical and technical improvement. Here, we analysed the trends in nerve block research and compared contributions from different countries, institutions, journals, and authors. Methods: We extracted all studies concerning nerve block published between 1997 and 2021 from the Web of Science database. Microsoft Excel and VOSviewer were employed to collect publication data, analyse publication trends, and visualize relevant results. Results: A total of 6,437 publications with 111,612 citations were identified between 1997 and 2021. The United States contributed the greatest number of publications (2010), whereas China ranked second (518). The Regional Anesthesia & Pain Medicine journal had published the most papers concerning nerve block. Harvard University and Mariano ER were the most productive institution and author, respectively, in the field. Keywords were categorized into five clusters: the association between nerve block and anaesthesia or analgesia, local anaesthetic drugs for nerve block, nerve block techniques, nerve block for postoperative analgesia, and nerve block for oral local anaesthesia. Management-related research was a heavily researched topic in the field. Conclusions: We concluded that the United States contributed the most studies, and developing countries, led by China, are also encouraging study in this area. The exploration of new drugs in the fields of nerve block, multi-modal analgesia after surgery, treatment of chronic pain, analgesia for thoracic and abdominal surgeries, and analgesic interventions in oral therapy is considered as a potential focus for future research.

A randomized trial to determine the minimum effective lidocaine volume for median nerve block using hydrodissection

Ultrasound-guided hydrodissection with 5% dextrose in water (DW5) creates a peri-nervous compartment, separating the nerve from the neighboring anatomical structures. The aim of this randomized study was to determine the minimum volume of lidocaine 2% with epinephrine 1:200,000 required when using this technique to achieve an effective median nerve block at the elbow in 95% of patients (MEAV95). Fifty-two patients scheduled for elective hand surgery received an ultrasound-guided circumferential perineural injection of 4 ml DW5 and an injection of local anesthetic (LA) following a biased coin up-and-down sequential allocation method. A successful block was defined as a light touch completely suppressed on the two distal phalanges of the index finger within a 30-min evaluation period. The MEAV95 of lidocaine 2% with epinephrine was 4 ml [IQR 3.5–4.0]. Successful median nerve block was obtained in 38 cases (82.6%) with median onset time of 20.0 [10.0–21.2] minutes (95% CI 15–20). The analgesia duration was 248 [208–286] minutes (95% CI 222–276). Using an ultrasound-guided hydrodissection technique with DW5, the MEAV95 to block the median nerve at the elbow with 2% lidocaine with epinephrine was 4 ml [IQR 3.5–4.0]. This volume is close to that usually recommended in clinical practice.Trial registration clinicaltrials.gov. NCT02438657, Date of registration: May 8, 2015.

Reduction of leakage from insertion site during continuous femoral nerve block with catheter-through-needle versus catheter-over-needle technique for postoperative analgesia after total knee arthroplasty: a randomized controlled trial

Background Continuous femoral nerve block (CFNB) is a common procedure used for postoperative analgesia in total knee arthroplasty. Continuous nerve block using a conventional needle (catheter-through-needle/CTN) is complicated by leakage of the anesthetic from the catheter insertion site. A different type of needle (catheter-over-needle/ CON) is now available, which is believed to reduce leakage as the diameter of the catheter is larger than that of the needle. The purpose of this study was to compare the incidence of leakage from the catheter insertion site during CFNB while using CTN and CON for postoperative analgesia after total knee arthroplasty (TKA). Methods This prospective, randomized, single-blinded controlled study included 60 patients who were scheduled for TKA at our facility between May 2016 and November 2017. Patients were randomly allocated to the CTN or CON groups. All patients in both groups received CFNB and sciatic nerve block for postoperative analgesia. The administration of 0.16% levobupivacaine mixed with 6 mg of indigo carmine (a dye added to easily identify leakage) was started at 6 ml/h at the end of surgery. The primary outcome was the incidence of leakage from the catheter insertion site. We further investigated the degree of leakage, the incidence of catheter migration, pain scores using the numerical rating scale at 48 h postoperatively, and the number of days until the operated knee could be flexed 120 degrees postoperatively in both groups. Results The CON group had a significantly lower incidence and degree of leakage from the catheter insertion site. There were no significant differences in other measurement outcomes. Conclusions Use of CON reduces the incidence of leakage from the catheter insertion site during CFNB in the use of postoperative analgesia for total knee arthroplasty. Future research is needed to determine additional benefits of using CON related to decreased leakage. Trial registration The study was registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000021537), prospectively registered on 18 March 2016.