Predictive Role of Admission Venous Lactate Level in Patients with Upper Gastrointestinal Bleeding: A Prospective Observational Study

Upper gastrointestinal bleeding (UGIB) is one of the most common emergencies. Risk stratification is essential in patients with this potentially life-threatening condition. The aim of this prospective study was to evaluate the usefulness of the admission venous lactate level in predicting clinical outcomes in patients with UGIB. All consecutive adult patients hospitalized due to UGIB were included in the study. The clinical data included the demographic characteristics of the observed population, etiology of UGIB, need for surgical intervention and intensive care, bleeding recurrence, and mortality rates. Venous lactate was measured in all patients on admission. Logistic regression analyses were used to calculate the odds ratios (OR) of lactate levels for all outcomes. The receiver operating characteristic (ROC) curve was used to determine the accuracy of lactate levels in measuring clinical outcomes, while Youden index was used to calculate the best cut-off points. A total of 221 patients were included in the study (151M; 70F). There were 24 cases of UGIB recurrence (10.8%), 19 patients (8.6%) required surgery, and 37 individuals (16.7%) required intensive care. Mortality rate was 11.3% (25 cases). The logistic regression analysis showed statistically significant association between admission venous lactate and all clinical outcomes: mortality (OR = 1.39, 95%CI: 1.22–1.58, p < 0.001), recurrence of bleeding (OR = 1.16, 95%CI: 1.06; 1.28, p = 0.002), surgical intervention (OR = 1.17, 95%CI: 1.06–1.3, p = 0.002) and intensive care (OR = 1.33, 95%CI: 1.19–1.5, p < 0.001). The ROC curve analysis showed a high predictive value of lactate levels for all outcomes, especially mortality: cut-off point 4.3 (AUC = 0.82, 95%CI: 0.72–0.92, p < 0.001) and intensive care: cut-off point 4.2 (AUC = 0.76, 95%CI: 0.66–0.85, p < 0.001). Admission venous lactate level may be a useful predictive factor of clinical outcomes in patients with UGIB.

Electrochemical Detection of Lactate Produced by Foodborne Presumptive Lactic Acid Bacteria

Background: The detection of lactate is an important indicator of freshness, stability, and storage stability of products as well as degree of fermentation in food industry. In addition, it can be used as a diagnostic tool in patients’ healthcare since it is known that the lactate level in blood increases in some pathological conditions including septic shock, tissue hypoxia, and sepsis. Thus, determination of lactate level plays an important role in not only food industry but also health fields. At this point, biosensor has become important to detect lactate due to having many advantages like rapid, cheap and easy to use. Methods and Results: In the current study, amperometric lactate biosensors based on lactate oxidase immobilization (with nafion 5% wt) were designed and limit of detection, linear range and sensitivity values were determined, which were found as 31 μM, 50-350 μM and 0.04 μA.μM-1.cm-2, respectively. Then, it was used for the measurement of lactic acid produced by 6 different and morphologically identified presumptive lactic acid bacteria (LAB) which were isolated from different naturally fermented cheese samples for this study. Then, the biosensors were used to perform lactate measurements successfully within 3 minutes for each sample even few of them were out of the limit of detection. Conclusion: Electrochemical biosensors should be alternative and quick solutions for measurement of lactate metabolites instead of using classical methods which are required long working time. Besides, it is the first study to measure lactate produced by foodborne LAB as real sample with a biosensor.

Target blood pressure management during cardiopulmonary bypass improves lactate levels after cardiac surgery: a randomized controlled trial

Background Hyperlactatemia is associated with a poor prognosis in cardiac surgery patients. This study explored the impact of target blood pressure management during cardiopulmonary bypass (CPB) on blood lactate levels after cardiac surgery. Methods Adult patients undergoing cardiac valve surgery between 20/1/2020 and 30/6/2020 at Shanghai Chest Hospital were enrolled. The patients were randomized into a low mean arterial pressure (L-MAP) group (target MAP between 50 and 60 mmHg) or a high mean arterial pressure (H-MAP) group (target MAP between 70 and 80 mmHg), n = 20 for each. Norepinephrine was titrated only during CPB to maintain MAP at the target level. Blood lactate levels in the two groups were detected before the operation (T0), at the end of CPB (T1), at the end of the operation (T2), 1 h after the operation (T3), 6 h after the operation (T4) and 24 h after the operation (T5). The primary outcome was the blood lactate level at the end of the operation (T2). The secondary outcomes included the blood lactate level at T1, T3, T4, and T5 and the dose of epinephrine and dopamine within 24 h after the operation, time to extubation, length of stay in the ICU, incidence of readmission within 30 days, and mortality within 1 year. Results Forty patents were enrolled and analyzed in the study. The lactate level in the H-MAP group was significantly lower than that in the L-MAP group at the end of the operation (3.1 [IQR 2.1, 5.0] vs. 2.1 [IQR 1.7, 2.9], P = 0.008) and at the end of CPB and 1 hour after surgery. The dose of epinephrine within 24 h after the operation, time to extubation and length of stay in the ICU in the L-MAP group were significantly higher than those in the H-MAP group. Conclusions Maintaining a relatively higher MAP during CPB deceased the blood lactate level at the end of surgery, reduced epinephrine consumption, and shortened the time to extubation and length of stay in the ICU after surgery. Trial registration This single-center, prospective, RCT has completed the registration of the Chinese Clinical Trial Center at 8/1/2020 with the registration number ChiCTR2000028941. It was conducted from 20/1/2020 to 30/6/2020 as a single, blinded trial in Shanghai Chest Hospital.

Study of hepatoprotective effect of bearberry leaves extract under insulin resistance in rats

The aim of our study was to evaluate the antidiabetic and hepatoprotective efficacy of dry extract from bearberry leaves enriched with arginine in dexamethasone induced IR. Materials and methods. IR was induced in rats by low dose intraperitoneally injections of dexamethasone. Dexamethasone-induced IR in rats was treated by bearberry leaves extract enriched with arginine. Thus, animals were randomized into several groups including intact animals and animals, which administered reference compounds and medications. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamine transferase (GGT) were determined in blood serum and liver homogenate, in addition, in blood serum we measured lactate dehydrogenase (LDH) activity and lactate level and glycogen content liver tissue. Also, for the purpose of our experiment, in liver tissue were determined: thiobarbituric acid reactive substances (TBARS), diene conjugates (DC), and reduced glutathione (GSH) content; and superoxide dismutase (SOD), glutathione peroxidase (Gpx), and catalase (CAT) activities. All indices were determined using generally accepted unified methods or commercially available kits. Results. Long-term dexamethasone administration led to an increase in AST, ALT and GGT overall activity in the liver homogenate and serum; this could be the result of increased permeability of hepatocyte plasma membranes, as well as their enhanced synthesis in the liver. Studied extract ameliorate these indices of liver injury. Evaluation of indices that reflected oxidative stress and the antioxidant system status in liver confirmed oxidative stress development in IR rats` liver. Administration of arginine enriched bearberry leaves extract decrease TBARS and DC content in liver tissue, at the same time, improve SOD, Gpx, and CAT activities and increase GSH content. Conclusions. Bearberry leaves dry extract enriched with arginine inhibit oxidative stress development, improve membrane integrity, and normalize some indices of carbohydrate metabolism, particularly glycogen content in liver and lactate level in blood.

Predictive Value of Cerebrospinal Fluid Lactate Level for the Diagnosis of Bacterial Meningitis following Cranial Surgery

Background:To distinguish post-neurosurgical bacterial meningitis (PNBM) from aseptic meningitis is difficult. Inflammatory and biochemical cerebrospinal fluid (CSF) changes mimic those classically observed after CNS surgery. CSF lactate assay has therefore been proposed as a useful PNBM marker. Objective:To determine the value of cerebrospinal fluid (CSF) lactate level for the identification of bacterial meningitis following cranial surgery. Methods:Between January 2016 and December 2016, a prospective clinical study was done in Department of Neurosurgery, in which all patients with clinical suspicion of PNBM were enrolled. Patients with clinical suspicion of bacterial meningitis BM were categorized, according to preset criteria, into 3 groups: (1) proven BM; (2) presumed BM, and (3) nonbacterial meningeal syndrome. CSF markers were plotted in a receiver operating curve (ROC) to evaluate their diagnostic accuracy. Results:The study included 70 patients. We obtained 65 CSF samples from patients with clinical suspicion of BM by CSF analysis. 20 corresponded to proven BM, 7 to probable BM and 38 to excluded BM. Mean lactate in CSF was: 8.4 ±3.0 mmol /l for proven BM, 4.8 ± 0.99 mmol /l for probable BM and 2.08 ± 0.822 mmol/l for excluded BM (P < .001). Conclusion: CSF lactate level has good predictive value to distinguish BM from aseptic meningitis with sensitivity of 90% and specificity: 87% at cut-off value: 4.0 mmol/l.

Serum Lactate Level as a Predictor for Blood Transfusion in Postpartum Hemorrhage

Objective Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity and mortality. At present, there are no reliable clinical or laboratory indicators to identify which patients might require blood transfusions during a PPH. Serum lactate has long been used as an early biomarker of tissue hypoperfusion in trauma settings. The aim of this study is to understand serum lactate's role in the management of obstetric hemorrhage. Study Design A retrospective chart review was performed of women who delivered between 2016 and 2019 at our institution and experienced a PPH. The patients were divided into two groups: those with a normal serum lactate level, defined as ≤2 mmol/L, and those with an abnormal serum lactate level, defined as >2 mmol/L. Need for packed red blood cell transfusion, as part of the resuscitation, was assessed for both groups. Results During the study period, 938 women experienced PPH. Of these, 108 (11.5%) had a normal serum lactate, ≤2 mmol/L, and 830 (88.5%) had an abnormal lactate, >2 mmol/L. Women with elevated lactate levels were more likely to receive a blood transfusion versus those with a normal lactate level (57.0 vs. 46.3%, p = 0.035, respectively). Additionally, the average number of blood transfusions administered was significantly higher in the abnormal lactate group versus in the normal lactate group (1.34 vs. 0.97, respectively, p = 0.004). In a multivariable linear regression model, increasing serum lactate levels were found to be predictive of requiring more than 1 unit of blood (p < 0.001). Conclusion Women with elevated serum lactate levels were more likely to require blood transfusions during a PPH versus those with a normal serum lactate level. Thus, serum lactate levels are useful as an early indicator of requirement for blood transfusion in the management of obstetric hemorrhage. Key Points

Abstract 10522: Early Lactate Clearance is Associated With Survival in a National Cohort of Refractory Out-of-Hospital Cardiac Arrest Patients Managed With Extracorporeal Cardiopulmonary Resuscitation

Introduction: In refractory out-of-hospital cardiac arrest (OHCA), prolonged whole-body ischemia with global tissue injury proceeds even after achievement of reperfusion with extracorporeal cardiopulmonary resuscitation (eCPR). Hypothesis: Biomarkers reflecting ischemia and inflammation may be used for prognostication of refractory OHCA managed with eCPR. Methods: This nationwide retrospective study included patients (≥18 years) with refractory OHCA managed with eCPR in Denmark (2011 to 2020). Biomarker levels at admission, at 24 hours (lactate, leukocytes, and platelets), and repeated measures of lactate after eCPR initiation were analyzed. Lactate clearance was calculated as (admission lactate - post eCPR lactate) / admission lactate x100%. Results: Two hundred eighteen patients (80% male; age 52±12yrs) were included. Primary cause of OHCA was acute myocardial infarction (63%), 69% had shockable primary rhythm and 86% witnessed OHCA with a median low-flow time of 105 minutes (Q1-Q3: 86-124 min.). Fifty-three (24%) survived to hospital discharge. Survivors had a significantly lower lactate level at admission (13.1 vs. 15.4 mmol/l, p=0.004) and after 24 hours (2.8 vs. 5.0, p=0.001), and a significantly higher admission platelet level (181 vs. 153 x10 9 /l, p=0.03). No difference in admission levels of leukocytes nor leukocytes and platelets after 24 hours were found between survivors and non-survivors. Lactate clearance was available for 68% and 79% of patients alive after 8 and 24 hours, respectively. All survivors had a lactate level less than admission lactate at 8 hours (lactate clearance >0%) and had cleared >25% of admission lactate at 24 hours after eCPR initiation. There was a significant difference in survival between quartiles of lactate clearance at 8 hours after eCPR initiation (Figure 1). Conclusion: In conclusion, early lactate clearance after eCPR initiation was associated with survival to discharge in refractory OHCA-patients.

A COMPARATIVE STUDY OF PERITONITIS ASSOCIATED HYPERLACTAMIA FOR EVALUATING MORTALITY IN SECONDARY PERITONITIS

Lactate levels are normally maintained at less than 1.5 mmol/L using a delicate balance between production and clearance (by liver and kidneys). Hyperlactemia has shown correlation with higher mortality. In our study on 30 indoor patients of perforation peritonitis in SMS medical college, Jaipur – we found that higher lactate level (> 4) is associated with higher ventilator need (80%) and hence higher mortality (60%). Keywords: Hyperlactemia.