Intrathecal ropivacaine 5 mg/ml for outpatient knee arthroscopy: a comparison with lidocaine 10 mg/ml

Lidocaine vs. Other Local Anesthetics in the Development of Transient Neurologic Symptoms (TNS) Following Spinal Anesthesia: A Meta-Analysis of Randomized Controlled Trials

The use of lidocaine in spinal anesthesia may increase the risk of transient neurological symptoms (TNS) according to previous meta-analyses. However, the previous meta-analyses lacked data on some other local anesthetics and thus, more evaluations are still needed to compare the effect of lidocaine on the development of TNS. The objective of this study was to compare the risk of TNS according to lidocaine versus other local anesthetics in patients undergoing spinal anesthesia. A total of 39 randomized controlled trials with 4733 patients were analyzed. The incidence of TNS was 10.8% in the lidocaine group and was 2.2% in the control groups (risk ratio (RR) 4.12, 95% confidence interval (CI) 3.13 to 5.43, p < 0.001). In subgroup analysis, lidocaine increased the incidence of TNS compared with other local anesthetics except mepivacaine, ropivacaine or sameridine. The risk of TNS was higher in the hyperbaric (p < 0.001) or isobaric lidocaine (p < 0.001) group compared with the control group, but there were no differences found between the two groups when hypobaric lidocaine was administered (p = 1.00). This study confirmed that lidocaine for spinal anesthesia still causes TNS more frequently than most other local anesthetics, especially when hyperbaric or isobaric lidocaine was used.

Transient neurological symptoms (TNS) following spinal anaesthesia with lidocaine versus other local anaesthetics in adult surgical patients: a network meta-analysis

BACKGROUND

Spinal anaesthesia has been implicated as one of the possible causes of neurological complications following surgical procedures. This painful condition, occurring during the immediate postoperative period, is termed transient neurological symptoms (TNS) and is typically observed after the use of spinal lidocaine. Alternatives to lidocaine that can provide high-quality anaesthesia without TNS development are needed. This review was originally published in 2005, and last updated in 2009.

OBJECTIVES

To determine the frequency of TNS after spinal anaesthesia with lidocaine and compare it with other types of local anaesthetics by performing a meta-analysis for all pair-wise comparisons, and conducting network meta-analysis (NMA) to rank interventions.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Elsevier Embase, and LILACS on 25 November 2018. We searched clinical trial registries and handsearched the reference lists of trials and review articles.

SELECTION CRITERIA

We included randomized and quasi-randomized controlled trials comparing the frequency of TNS after spinal anaesthesia with lidocaine to other local anaesthetics. Studies had to have two or more arms that used distinct local anaesthetics (irrespective of the concentration and baricity of the solution) for spinal anaesthesia in preparation for surgery. We included adults who received spinal anaesthesia and considered all pregnant participants as a subgroup. The follow-up period for TNS was at least 24 hours.

DATA COLLECTION AND ANALYSIS

Four review authors independently assessed studies for inclusion. Three review authors independently evaluated the quality of the relevant studies and extracted the data from the included studies. We performed meta-analysis for all pair-wise comparisons of local anaesthetics, as well as NMA. We used an inverse variance weighting for summary statistics and a random-effects model as we expected methodological and clinical heterogeneity across the included studies resulting in varying effect sizes between studies of pair-wise comparisons. The NMA used all included studies based on a graph theoretical approach within a frequentist framework. Finally, we ranked the competing treatments by P scores.

MAIN RESULTS

The analysis included 24 trials reporting on 2226 participants of whom 239 developed TNS. Two studies are awaiting classification and one is ongoing. Included studies mostly had unclear to high risk of bias. The NMA included 24 studies and eight different local anaesthetics; the number of pair-wise comparisons was 32 and the number of different pair-wise comparisons was 11. This analysis showed that, compared to lidocaine, the risk ratio (RR) of TNS was lower for bupivacaine, levobupivacaine, prilocaine, procaine, and ropivacaine with RRs in the range of 0.10 to 0.23 while 2-chloroprocaine and mepivacaine did not differ in terms of RR of TNS development compared to lidocaine. Pair-wise meta-analysis showed that compared with lidocaine, most local anaesthetics were associated with a reduced risk of TNS development (except 2-chloroprocaine and mepivacaine) (bupivacaine: RR 0.16, 95% confidence interval (CI) 0.09 to 0.28; 12 studies; moderate-quality evidence; 2-chloroprocaine: RR 0.09, 95% CI 0.01 to 1.51; 2 studies; low-quality evidence; levobupivacaine: RR 0.13, 95% CI 0.02 to 0.69; 2 studies; low-quality evidence; mepivacaine: RR 1.01, 95% CI 0.18 to 5.82; 4 studies; very low-quality evidence; prilocaine: RR 0.18, 95% CI 0.07 to 0.49; 4 studies; moderate-quality evidence; procaine: RR 0.14, 95% CI 0.04 to 0.52; 2 studies; moderate-quality evidence; ropivacaine: RR 0.10, 95% CI 0.01 to 0.78; 2 studies; low-quality evidence). We were unable to perform any of our planned subgroup analyses due to the low number of TNS events.

AUTHORS' CONCLUSIONS

Results from both NMA and pair-wise meta-analysis indicate that the risk of developing TNS after spinal anaesthesia is lower when bupivacaine, levobupivacaine, prilocaine, procaine, and ropivacaine are used compared to lidocaine. The use of 2-chloroprocaine and mepivacaine had a similar risk to lidocaine in terms of TNS development after spinal anaesthesia. Patients should be informed of TNS as a possible adverse effect of local anaesthesia with lidocaine and the choice of anaesthetic agent should be based on the specific clinical context and parameters such as the expected duration of the procedure and the quality of anaesthesia. Due to the very low- to moderate-quality evidence (GRADE), future research efforts in this field are required to assess alternatives to lidocaine that would be able to provide high-quality anaesthesia without TNS development. The two studies awaiting classification and one ongoing study may alter the conclusions of the review once assessed.

Revealing oxidative damage to enzymes of carbohydrate metabolism in yeast: An integration of 2D DIGE, quantitative proteomics, and bioinformatics

Clinical usage of lidocaine, a pro-oxidant has been linked with severe, mostly neurological complications. The mechanism(s) causing these complications is independent of the blockade of voltage-gated sodium channels. The budding yeast Saccharomyces cerevisiae lacks voltage-gated sodium channels, thus provides an ideal system to investigate lidocaine-induced protein and pathway alterations. Whole-proteome alterations leading to these complications have not been identified. To address this, S. cerevisiae was grown to stationary phase and exposed to an LC50 dose of lidocaine. The differential proteomes of lidocaine treatment and control were resolved 6 h post exposure using 2D DIGE. Amine reactive dyes and carbonyl reactive dyes were used to assess protein abundance and protein oxidation, respectively. Quantitative analysis of these dyes (⩾ 1.5-fold alteration, p ⩽ 0.05) revealed a total of 33 proteoforms identified by MS differing in abundance and/or oxidation upon lidocaine exposure. Network analysis showed enrichment of apoptotic proteins and cell wall maintenance proteins, while the abundance of proteins central to carbohydrate metabolism, such as triosephosphate isomerase and glyceraldehyde-3-phosphate dehydrogenase, and redox proteins superoxide dismutase and peroxiredoxin were significantly decreased. Enzymes of carbohydrate metabolism, such as phosphoglycerate kinase and enolase, the TCA cycle enzyme aconitase, and multiple ATP synthase subunits were found to be oxidatively modified. Also, the activity of aconitase was found to be decreased. Overall, these data suggest that toxic doses of lidocaine induce significant disruption of glycolytic pathways, energy production, and redox balance, potentially leading to cell malfunction and death.

Despite differences in cytosolic calcium regulation, lidocaine toxicity is similar in adult and neonatal rat dorsal root ganglia in vitro

BACKGROUND

Neuraxial local anesthetics may have neurological complications thought to be due to neurotoxicity. A primary site of action of local anesthetics is the dorsal root ganglia (DRG) neuron. Physiologic differences have been noted between young and adult DRG neurons; hence, the authors examined whether there were any differences in lidocaine-induced changes in calcium and lidocaine toxicity in neonatal and adult rat DRG neurons.

METHODS

DRG neurons were cultured from postnatal day 7 (P7) and adult rats. Lidocaine-induced changes in cytosolic calcium were examined with the calcium indicator Fluo-4. Cells were incubated with varying concentrations of lidocaine and examined for viability using calcein AM and ethidium homodimer-1 staining. Live imaging of caspase-3/7 activation was performed after incubation with lidocaine.

RESULTS

The mean KCl-induced calcium transient was greater in P7 neurons (P < 0.05), and lidocaine significantly inhibited KCl-induced calcium responses in both ages (P < 0.05). Frequency distribution histograms of KCl-evoked calcium increases were more heterogeneous in P7 than in adult neurons. With lidocaine, KCl-induced calcium transients in both ages became more homogeneous but remained different between the groups. Interestingly, cell viability was decreased by lidocaine in a dose-dependent manner similarly in both ages. Lidocaine treatment also activated caspase-3/7 in a dose- and time-dependent manner similarly in both ages.

CONCLUSIONS

Despite physiological differences in P7 and adult DRG neurons, lidocaine cytotoxicity is similar in P7 and adult DRG neurons in vitro. Differences in lidocaine- and KCl-evoked calcium responses suggest the similarity in lidocaine cytotoxicity involves other actions in addition to lidocaine-evoked effects on cytosolic calcium responses.

Role of regional anesthesia in the ambulatory environment

The use of local anesthetics in ambulatory surgery offers multiple benefits in line with the goals of modern-day outpatient surgery. A variety of regional techniques can be used for a wide spectrum of procedures; all are shown to reduce postprocedural pain; reduce the short-term need for opiate medications; reduce adverse effects, such as nausea and vomiting; and reduce the time to dismissal compared with patients who do not receive regional techniques. Growth in ambulatory procedures will likely continue to rise with future advances in surgical techniques, changes in reimbursement, and the evolution of clinical pathways that include superior, sustained postoperative analgesia. Anticipating these changes in practice, the role of, and demand for, regional anesthesia in outpatient surgery will continue to grow.

Transient neurological symptoms after spinal anaesthesia with levobupivacaine 5 mg/ml or lidocaine 20 mg/ml

BACKGROUND

Transient neurological symptoms (TNS) after spinal anaesthesia have been reported most commonly in association with lidocaine, but have been observed with other local anaesthetics. The aim of this prospective, randomized, double-blind study was to investigate the incidence of TNS after spinal anaesthesia with either levobupivacaine or lidocaine.

METHODS

Patients undergoing inguinal hernia, appendectomy, varicose vein or minor orthopaedic operations were included in the study (60 patients; 47 male, 13 female, overall mean age 30 years). All patients had an American Society of Anesthesiologists score of I or II. The patients were randomly assigned to receive spinal anaesthesia with either 20 mg isobaric levobupivacaine (5 mg/ml) or 80 mg isobaric lidocaine (20 mg/ml). Onset of sensory and motor block and side effects were recorded. On post-operative days 1, 2, and 3, patients were interviewed by an investigator blinded to the spinal anaesthetic used. The patients were classified as having TNS if, following recovery from anaesthesia, there was pain in the buttocks, thighs and/or lower limbs.

RESULTS

In the levobupivacaine group, one patient (3.33%) experienced TNS, whereas in the lidocaine group, eight (26.6%) experienced TNS (P=0.002). Maximum times to arrival of sensory blocks were shorter with lidocaine (P<0.001). The levobupivacaine and lidocaine groups did not differ significantly in terms of the highest dermatome included in sensory block or motor block grade.

CONCLUSION

After spinal anaesthesia with levobupivacaine, the incidence of TNS was much less than after lidocaine. However, it appears that TNS may occur in association with levobupivacaine.