Intravenous Lidocaine Does Not Improve Neurologic Outcomes after Cardiac Surgery

Abstract

Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New Background Cognitive decline after cardiac surgery occurs frequently and persists in a significant proportion of patients. Preclinical studies and human trials suggest that intravenous lidocaine may confer protection in the setting of neurologic injury. It was hypothesized that lidocaine administration would reduce cognitive decline after cardiac surgery compared to placebo. Methods After institutional review board approval, 478 patients undergoing cardiac surgery were enrolled into this multicenter, prospective, randomized, double-blinded, placebo-controlled, parallel group trial. Subjects were randomized to lidocaine 1 mg/kg bolus after the induction of anesthesia followed by a continuous infusion (48 μg · kg−1 · min−1 for the first hour, 24 μg · kg−1 · min−1 for the second hour, and 10 μg · kg−1 · min−1 for the next 46 h) or saline with identical volume and rate changes to preserve blinding. Cognitive function was assessed preoperatively and at 6 weeks and 1 yr postoperatively using a standard neurocognitive test battery. The primary outcome was change in cognitive function between baseline and 6 weeks postoperatively, adjusting for age, years of education, baseline cognition, race, and procedure type. Results Among the 420 allocated subjects who returned for 6-week follow-up (lidocaine: N = 211; placebo: N = 209), there was no difference in the continuous cognitive score change (adjusted mean difference [95% CI], 0.02 (−0.05, 0.08); P = 0.626). Cognitive deficit (greater than 1 SD decline in at least one cognitive domain) at 6 weeks occurred in 41% (87 of 211) in the lidocaine group versus 40% (83 of 209) in the placebo group (adjusted odds ratio [95% CI], 0.94 [0.63, 1.41]; P = 0.766). There were no differences in any quality of life outcomes between treatment groups. At the 1-yr follow-up, there continued to be no difference in cognitive score change, cognitive deficit, or quality of life. Conclusions Intravenous lidocaine administered during and after cardiac surgery did not reduce postoperative cognitive decline at 6 weeks.

Postoperative changes in cognition and cerebrospinal fluid neurodegenerative disease biomarkers

“…Second, these data do not show a correlation between AD‐related CSF biomarker change and cognitive change from before to 6 weeks after surgery, a time interval during which cognitive deficits have been detected after anesthesia and surgery in numerous prior studies 10–12,16,17,40,53–70 . Yet, this does not exclude the possibility that such a correlation exists over a longer postoperative follow‐up period.…”

“…Second, these data do not show a correlation between AD-related CSF biomarker change and cognitive change from before to 6 weeks after surgery, a time interval during which cognitive deficits have been detected after anesthesia and surgery in numerous prior studies. [10][11][12]16,17,40,[53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70] Yet, this does not exclude the possibility that such a correlation exists over a longer postoperative follow-up period. However, with longer time intervals postsurgery, it becomes less clear that any changes in CSF biomarkers or cognition are directly related to the surgery; this is partly why the perioperative neurocognitive disorders nomenclature 11 does not use the modifier "perioperative" for cognitive dysfunction occurring >1-year postsurgery.…”

Neuropsychological Tests in Post-operative Cognitive Dysfunction: Methods and Applications

“…The difference of a single test between the post-operative and preoperative scores is compared with the SD of the baseline scores of the corresponding test. POCD is defined as the changing scores of no less than one test of the testing battery, which are one SD or more (Royse et al, 2011;Klinger et al, 2019). At the same time, exceeding 1 SD is regarded as mild cognitive decline, 1.5 SDs is the moderate cognitive decline and 2 >SDs are severe cognitive decline.…”

Post-Operative Cognitive Impairment: A Cognitive Epidemiology Perspective

“…To name one landmark study included in the meta-analysis, the International Study of Post-Operative Cognitive Dysfunction (ISPOCD 1), found that among 1011 older surgical patients recruited in eight European countries and the USA, patients with more than a high school education had even a halved risk of POCD at one week after surgery compared with patients with less than high school education ( Moller et al 1998 ). Studies from various European and Asian countries and the USA that were not included in the 2017 meta-analysis ( Grichnik et al 1999 ) or published thereafter ( Bendikaite and Vimantaite 2020 ; Ehsani et al 2020 ; Huang et al 2020a ; Klinger et al 2019 ; Li et al 2020 ; Wang et al 2018 ; Yuhe et al 2020 ; Zhang et al 2019 ; Zhou et al 2020 ) too, consistently indicate that patients with a lower educational level are at increased POCD risk at discharge ( Zhang et al 2019 ) within days of surgery ( Ehsani et al 2020 ; Li et al 2020 ; Zhao et al 2020 ; Zhou et al 2020 ) but also during six to 12 weeks after surgery ( Grichnik et al 1999 ; Yuhe et al 2020 ). The fact that observations extend to several months after surgery is important because studies on POCD with longer follow-up periods offer preferred scope for conclusions: during shorter follow-up periods immediate effects of surgery on brain function including a potential influence of POD can prevail.…”