Blood Lactate or Lactate Clearance: Which Is Robust to Predict the Neurological Outcomes after Cardiac Arrest? A Systematic Review and Meta-Analysis

Abstract

Aims Lactate and lactate clearance were supposed to be associated with cardiac arrest outcomes, but studies obtained different results. Thus, we conducted this meta-analysis to investigate the association between lactate or lactate clearance and neurological outcomes and their usefulness for prediction of neurological outcomes. Methods We conducted a systematic search in PubMed, Web of science, EMBASE, Medline, and Google Scholar until May 1, 2018, for relevant studies. Studies reporting lactate, lactate clearance on admission, or other time points after admission associated with neurological outcomes were included in our analysis. Pooled effect date was shown as weighed mean difference (WMD) and 95% confidence interval (CI). To measure the usefulness of lactate on admission to predict neurological outcomes, we also pooled the data of diagnostic test. Results 23 studies involving 6720 cardiac arrest (CA) patients were included. Results from our analysis indicated that patients with good neurological outcomes tended to have a lower lactate level on admission (WMD: -2.66 mmol/L, 95%CI: -3.39 to -1.93) and 12h, 24h, and 48h after admission (P<0.001). Furthermore, the pooled AUC for lactate level on admission to predict neurological outcomes was 0.77 (95%CI: 0.73-0.80). However, a significant association between lactate clearance and neurological outcomes was only found in 24h but not 12h lactate clearance rate. Conclusions Lactate levels on admission and all time points up to 48h were associated with neurological outcomes after CA, whereas the association between lactate clearance and neurological outcomes was not so stable. Lactate was a more robust surrogate marker than lactate clearance to predict neurological outcomes after CA.

Prognostic Abilities of Serial Neuron-Specific Enolase and Lactate and their Combination in Cardiac Arrest Survivors During Targeted Temperature Management

“…The prognostic value of serum lactate levels was studied in OHCA patients. A previous metaanalysis reviewed 22 articles with 6553 participants and, although the constituent studies were highly heterogeneous, lactate levels at 24, 48, and 72 h from admission were associated with poor neurological outcomes [13]. Like previous studies, our study also showed that all serial serum lactate levels from 0-72 h were associated with neurological outcomes.…”

“…Lactate is produced from anaerobic metabolism after hypoxic tissue injury. During cardiac arrest, the anoxic state leads to lactate accumulation, and the serum lactate level is likely to be a useful marker of brain hypoxia, as also recommended in the Utstein guidelines [13]. Conversely, decreased lactate is a surrogate marker for adequate tissue perfusion after the return of spontaneous circulation (ROSC) [14].…”

Early Clinical Predictors of Neurological Outcome in Children With Asphyxial Out-of-Hospital Cardiac Arrest Treated With Therapeutic Hypothermia

“…Serum lactate level is a good prognostic indicator for tissue perfusion deficit. It has recently been reported that blood lactate level measured on arrival is useful as a prognostic predictor for cardiac arrest in adult and neonates who undergo therapeutic hypothermia (16)(17)(18)(19). Lee et al reported that high serum lactate levels measured within 1 h of ROSC, were positively associated with hospital mortality and poor neurological outcomes in 443 adult OHCA patients treated with therapeutic hypothermia (17).…”

“…Lee et al reported that high serum lactate levels measured within 1 h of ROSC, were positively associated with hospital mortality and poor neurological outcomes in 443 adult OHCA patients treated with therapeutic hypothermia (17). A systematic review and meta-analysis also showed that high serum lactate levels on admission were associated with poor neurological outcomes after cardiac arrest, whereas the association between serum lactate clearance and neurological outcomes was not so stable (18). In the present study, it was found that an initial lactate level ≤80 mg/dL within 1 h of ROSC was positively associated with a 6-month favorable neurological outcome in pediatric asphyxial OHCA treated with therapeutic hypothermia.…”

Cardiac arrest survival post-resuscitation in-hospital (CASPRI)—a tool to predict neurological outcome after ROSC

“…A retrospective study of 236 cases of cardiac arrest by Dell'Anna et al [34] found that the first lactic acid concentration after ROSC was an independent risk factor for patients with poor neurological prognosis at 3 months. Zhou et al [35] conducted a meta-analysis of 23 studies involving a total of 6720 cardiac arrest patients and showed that patients with good neurological prognosis had lower plasma lactate concentrations than those with poor prognosis at admission, 12 h, 24 h, and 48 h after resuscitation. During cardiac arrest and CPR, the anaerobic glycolytic pathway is activated to cause lactic acid accumulation and microcirculation disorders, which further aggravate organ and tissue ischemia and hypoxia, thereby causing organ dysfunction, and leading to poor neurological prognosis.…”