Lidocaine dose-response effect on postoperative cognitive deficit: meta-analysis and meta-regression

Abstract

The true influence of the perioperative intravenous lidocaine on the development of postoperative cognitive deficit (POCD) in coronary artery bypass grafting (CABG) remains controversial. The principal aim is to undertake a meta-regression to determine whether moderator variables mediate the relationship between lidocaine and POCD. Areas covered: We searched the Web of Science, PubMed database, Scopus and the Cochrane Library database (up to June 2017) and systematically reviewed a list of retrieved articles. Our final review includes only randomized controlled trials (RCTs) that compared infusion of lidocaine and placebo during cardiopulmonary bypass (CPB). Mantel-Haenszel risk ratio (MH RR) and corresponding 95% confidence interval (CI) was used to report the overall effect and meta-regression analysis. A total of 688 patients in five RCTs were included. POCD occurred in 34% of all cases. Perioperative lidocaine reduces POCD (MH RR 0.702 (95% CI: 0.541-0.909). Younger age, male gender, longer CPB and higher concentration of lidocaine significantly mediate the relationship between lidocaine and POCD in favour of the neuroprotective effect of lidocaine. Expert commentary: The neuroprotective effect of lidocaine on POCD is consistent in spite of longer CPB time. A higher concentration of lidocaine strengthened the neuroprotective effect of lidocaine.

Prophylactic effect of intravenous lidocaine against cognitive deficit after cardiac surgery: A PRISMA-compliant meta-analysis and trial sequential analysis

“…Nevertheless, a lack of validation regarding the strength of evidence because TSA was not performed as well as the small number of patients in those meta-analyses remain important concerns. [ 21 , 22 ] Our findings from TSA showed that the prophylactic effect of intravenous lidocaine on cognitive dysfunction remained inconclusive at an early postoperative period. Furthermore, the association became nonsignificant when 1 study reporting a circulating lidocaine concentration up to 4.78 to 7.1 μg/mL [ 20 ] was removed.…”

“…Two previous meta-analyses [ 21 , 22 ] focused on 5 RCTs had suggested a correlation between the use of intravenous lidocaine and a reduced risk of cognitive deficit at about postoperative 2 weeks, but not at 8 to 10 weeks. Nevertheless, a lack of validation regarding the strength of evidence because TSA was not performed as well as the small number of patients in those meta-analyses remain important concerns.…”

Contemporary Neuroprotection Strategies during Cardiac Surgery: State of the Art Review

“…In addition, lignocaine was shown to increase susceptibility to POCD in diabetic patients [ 55 ]. Furthermore, in a meta-analysis involving 688 patients, lignocaine was administered as an infusion from the beginning of the anaesthetic induction to the next 48 h. Results revealed that higher concentrations of lignocaine were associated with more substantial neuroprotective effects [ 5 ].…”

“…The duration of CPB during cardiac surgery has been associated with a variety of adverse outcomes. Longer CPB times are a recognised risk factor for neurological sequelae following cardiac surgery; however, in a meta-analysis by Habibi et al, the use of lignocaine infusions combined with longer CPB times was associated with more favourable neurological outcomes [ 5 ]. Perfusion flow generated by CPB is usually non-pulsatile, which contrasts with the physiological pulsatile flow.…”

Effect of perioperative intravenous lidocaine on the incidence of short‐term cognitive function after noncardiac surgery: A meta‐analysis based on randomized controlled trials

“…Results of a meta-analysis showed that a higher concentration of lidocaine can be an effective neuroprotective agent on patients following heart surgery (Habibi et al, 2018). However, there is an ongoing debate in the literature on the effect of lidocaine on cognitive function in noncardiac surgery (Chen et al, 2015;Peng et al, 2016).…”