Blood lactate and lactate kinetics as treatment and prognosis markers for tissue hypoperfusion

Real-Time Measurements of Oral Mucosal Carbon Dioxide (POMCO2) Reveals an Inverse Correlation With Blood Pressure in a Porcine Model of Coagulopathic Junctional Hemorrhage

INTRODUCTION

Shock states that occur during, for example, profound hemorrhage can cause global tissue hypoperfusion leading to organ failure. There is an unmet need for a reliable marker of tissue perfusion during hemorrhage that can be followed longitudinally. Herein, we investigated whether longitudinal POMCO2 tracks changes in hemodynamics in a swine model of coagulopathic uncontrolled junctional hemorrhage.

MATERIALS AND METHODS

Female Yorkshire-crossbreed swine (n = 7, 68.1 ± 0.7 kg) were anesthetized and instrumented for continuous measurement of mean arterial pressure (MAP). Coagulopathy was induced by the exchange of 50 to 60% of blood volume with 6% Hetastarch over 30 minutes to target a hematocrit of <15%. A 4.5-mm arteriotomy was made in the right common femoral artery with 30 seconds of free bleeding. POMCO2 was continuously measured from baseline through hemodilution, hemorrhage, and a subsequent 3-h intensive care unit period. Rotational thromboelastometry and blood gases were measured.

RESULTS

POMCO2 and MAP showed no significant changes during the hemodilution phase of the experiment, which produced coagulopathy evidenced by prolonged clot formation times. However, POMCO2 increased because of the uncontrolled hemorrhage by 11.3 ± 3.1 mmHg and was inversely correlated with the drop (17.9 ± 5.9 mmHg) in MAP (Y = -0.4122*X + 2.649, P = .02, r2 = 0.686). In contrast, lactate did not significantly correlate with the changes in MAP (P = .35) or POMCO2 (P = .37).

CONCLUSIONS

Despite the logical appeal of measuring noninvasive tissue CO2 measurement as a surrogate for gastrointestinal perfusion, prior studies have only reported snapshots of this readout. The present investigation shows real-time longitudinal measurement of POMCO2 to confirm that MAP inversely correlates to POMCO2 in the face of coagulopathy. The simplicity of measuring POMCO2 in real time can provide an additional practical option for military or civilian medics to monitor trends in hypoperfusion during hemorrhagic shock.

Evaluation of Blood Lactate, Heart Rate, Blood Pressure, and Shock Index, and Their Association with Prognosis in Calves

Diseases in young calves received as emergencies are often associated with hypovolemic and/or septic shocks. The objectives of our study were to (1) assess the correlation between clinical hemodynamic parameters and blood L-lactates (LAC), systolic blood pressure (SBP), and the shock index (SI) recorded upon arrival; and (2) to evaluate how these parameters were related to short-term outcomes in calves under 4 months of age presented as emergencies. We conducted a single-observer prospective observational study on calves aged from 1 day to 4 months, presented to the Veterinary Clinic for Ruminants of Liège from December 2020 to May 2022. Forty-five calves were included in the study. The statistical analysis revealed a significant correlation between LAC and heart rate (r = 0.570; p < 0.05) and LAC and SI (r = 0.373; p < 0.05). A high LAC value at admission was significantly associated with a negative outcome (death) (p < 0.05). In calves suffering from obstructive digestive diseases, the SI was related to the outcome and the analysis indicated a cut-off value of 1.13 (Se = 0.77, Spe = 1). In conclusion, in our study, the initial blood L-lactate value was correlated with heart rate, the shock index, and the clinical shock score, and admission hyperlactatemia was associated with a poor prognosis in calves under 4 months of age. In this cohort, the shock index in calves suffering from digestive diseases was linked with mortality.

Association of lactate detection with in-hospital mortality in critically ill patients with acute myocardial infarction: a retrospective cohort study

OBJECTIVES

To assess the associations of lactate level or lactate clearance at different time points with in-hospital mortality in critically ill patients with acute myocardial infarction (AMI).

DESIGN

A cohort study.

SETTING

The Medical Information Mart for Intensive Care III database.

PARTICIPANT

490 AMI patients.

INTERVENTION

None.

PRIMARY AND SECONDARY OUTCOME MEASURES

In-hospital mortality of patients.

RESULTS

In total, 120 (24.49%) patients died at the end of follow-up. After adjusting for confounders, increased risk of in-hospital mortality in patients with AMI was observed in those with high lactate level (24 hours) (HR=1.156, 95%CI: 1.002 to 1.333). Increased lactate clearance (24 hours) was correlated with a decreased risk of in-hospital mortality in patients with AMI (HR=0.995, 95% CI: 0.994 to 0.997). The area under the curves (AUCs) of lactate level (24 hours) and lactate clearance (24 hours) were 0.689 (95% CI: 0.655 to 0.723) and 0.672 (95% CI: 0.637 to 0.706), respectively. The AUC of lactate level (24 hours) and lactate clearance (24 hours) was higher than lactate level (baseline).

CONCLUSIONS

Increased lactate level (24 hours) was associated with an elevated risk of in-hospital mortality in patients with AMI and increased lactate clearance (24 hours) was correlated with a decreased risk of in-hospital mortality in patients with AMI despite the age and genders.

Does lactate enhance the prognostic accuracy of the quick Sequential Organ Failure Assessment for adult patients with sepsis? A systematic review

OBJECTIVES

To investigate whether adding lactate to the quick Sequential (sepsis-related) Organ Failure Assessment (qSOFA) improves the prediction of mortality in adult hospital patients, compared with qSOFA alone.

DESIGN

Systematic review in accordance with Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies guidelines.

DATA SOURCES

Embase, Medline, PubMed, SCOPUS, Web of Science, CINAHL and Open Grey databases were searched in November 2020.

ELIGIBILITY CRITERIA

Original research studies published after 2016 comparing qSOFA in combination with lactate (LqSOFA) with qSOFA alone in adult patients with sepsis in hospital. The language was restricted to English.

DATA EXTRACTION AND SYNTHESIS

Title and abstract screening, full-text screening, data extraction and quality assessment (using Quality Assessment of Diagnostic Accuracy Studies-2) were conducted independently by two reviewers. Extracted data were collected into tables and diagnostic test accuracy was compared between the two tests.

RESULTS

We identified 1621 studies, of which 11 met our inclusion criteria. Overall, there was a low risk of bias across all studies. The area under the receiver operating characteristic (AUROC) curve for qSOFA was improved by the addition of lactate in 9 of the 10 studies reporting it. Sensitivity was increased in three of seven studies that reported it. Specificity was increased in four of seven studies that reported it. Of the six studies set exclusively within the emergency department, five published AUROCs, all of which reported an increase following the addition of lactate. Sensitivity and specificity results varied throughout the included studies. Due to insufficient data and heterogeneity of studies, a meta-analysis was not performed.

CONCLUSIONS

LqSOFA is an effective tool for identifying mortality risk both in adult inpatients with sepsis and those in the emergency department. LqSOFA increases AUROC over qSOFA alone, particularly within the emergency department. However, further original research is required to provide a stronger base of evidence in lactate measurement timing, as well as prospective trials to strengthen evidence and reduce bias.

PROSPERO REGISTRATION NUMBER

CRD42020207648.

Risk stratification in cardiogenic shock: a focus on the available evidence

Cardiogenic shock is a clinical syndrome which is defined as the presence of primary cardiac disorder that results in hypotension together with signs of organ hypoperfusion in the state of normovolaemia or hypervolaemia. It represents a complex life-threatening condition, characterized by a high mortality rate, that requires urgent diagnostic assessment as well as treatment; therefore, it is of paramount important to advocate for a thorough risk stratification. In fact, the early identification of patients that could benefit the most from more aggressive and invasive approaches could facilitate a more efficient resource allocation. This review attempts to critically analyse the current evidence on prognosis in cardiogenic shock, focusing in particular on clinical, laboratoristic and echocardiographic prognostic parameters. Furthermore, it focuses also on the available prognostic scores, highlighting the strengths and the possible pitfalls. Finally, it provides insights into future direction that could be followed in order to ameliorate risk stratification in this delicate subset of patients.

Regional citrate anticoagulation versus low molecular weight heparin for CRRT in hyperlactatemia patients: A retrospective case-control study

INTRODUCTION

There were controversial opinions on the use of regional citrate anticoagulation (RCA) versus low molecular weight heparin (LMWH) for continuous renal replacement therapy (CRRT) in hyperlactatemia patients, which was considered as one of the contraindications of citrate. The aim of our present study is to evaluate the efficacy and safety of RCA versus LMWH for CRRT in hyperlactatemia patients.

METHODS

Adult patients with hyperlactatemia who underwent RCA or LMWH CRRT in our center between January 2014 and March 2018 were retrospectively recruited. Filter lifespan, ultrafiltration, purification, bleeding, citrate accumulation, filter clot, and the infusion of blood production were evaluated as endpoints.

RESULTS

Of the 127 patients included in the original cohort, 81 and 46 accepted RCA and LMWH CRRT, respectively. The filter lifespan was significantly prolonged in the RCA group compared to the LMWH group (44.25 h [2 -83] vs. 24 h [4 -67], p < 0.001). The accumulated filter survival proportions were significantly improved in the RCA group compared to the LMWH group in the original cohort (p < 0.001) as well as the matched group (p < 0.001). The filters clotted more frequently in the LMWH group than in the RCA group in both of the original (52.2% vs 26.8%, p = 0.001) and matched cohort (58.6% vs 19.4%, p = 0.001). The bleeding complication was significantly reduced in the RCA group than in the LMWH group in the matched cohort (28.6% vs 4.5%, p = 0.04).

CONCLUSION

In critically ill patients with hyperlactatemia requiring CRRT, RCA is superior to LMWH in terms of filter lifespan and bleeding risk without significantly increased risk of citrate accumulation and citrate related metabolic complications. RCA most likely is a safe and effective anticoagulation method for CRRT in patients with hyperlactatemia.

Clinical Characteristics and Risk Factors for Critically Ill Patients with Carbapenem-Resistant Klebsiella pneumonia e (CrKP): A Cohort Study from Developing Country

BACKGROUND

Increasing evidence indicates carbapenem-resistant Klebsiella pneumoniae (CrKP) is increasingly prevalent in intensive care unit (ICU), but its clinical characteristics and risk factors remain unknown.

AIM

The aim of the present study was to evaluate clinical characteristics, risk factors in critically ill patients with CrKP infection.

METHODS

A retrospective study was included in patients from January 2013 to October 2019. Clinical data were collected from CrKP patients on the day of specimen collection admitted to ICU. Multivariable logistic regression was used for risk factors. Receiver operating curve (ROC) and the area under the curve (AUC) with DeLong method of MedCalc software were used. Two-way repeated-measures ANOVA analysis was used to analyze the characteristics of independent risk factors over time.

FINDINGS

A total of 147 adult patients with CrKP were screened, among them, 89 (median age 64.0 years, 66 (74.15%) males) patients with CrKP were finally included, of which 38 patients (42.7%) were non-survival group. Multivariate logistic regression analysis indicated that lactic acid (OR3.04 95% CI 1.38-6.68, P = 0.006), APACHE II score (OR 1.20, 95% CI 1.09-1.33, P < 0.001), tigecycline combined with fosfomycin treatment (OR0.15, 95% CI 0.04-0.65, P = 0.011) are independent risk factors for 28-day mortality in patients with CRKP infection (P<0.05). Combined lactic acid with APACHE II score could predict 28-day mortality, of which AUC value was 0.916 (95% CI, 0.847-0.985), with sensitivity 0.76 and specificity 0.98. ANOVA analysis showed that APACHE II score and lactic acid between the two groups at three-time points were statistically significant, which interactive with time and showed an upward and downward trend with time (P < 0.05).

CONCLUSION

Therapeutic strategy based on improving lactic acid and APACHE II would contribute to the outcome in patients with CrKP infection. Tigecycline combined with fosfomycin could reduce the 28-day mortality in patients with CrKP infection in developing country.

Regional citrate anticoagulation vs no-anticoagulation for CRRT in hyperlactatemia patients with increased bleeding risk: A retrospective cohort study

There are controversial opinions on the use of regional citrate anticoagulation (RCA) continuous renal replacement therapy (CRRT) in hyperlactatemia patients with increased bleeding risk. Patients with hyperlactatemia and increased bleeding risk who accepted RCA or no-anticoagulation CRRT in our center were retrospectively included. Eighty patients who underwent RCA-CRRT and 47 patients received no-anticoagulation CRRT were included. Filter lifespan was significantly longer in the RCA group than the no-anticoagulation group (44.5 hours [2-89] vs 24.5 hours [1.5-70], P < .001). The adjusted results demonstrated that patients in the no-anticoagulant group had significantly higher risk of filter failure (HR = 4.765, 95% CI 2.703-8.4, P < .001). Bleeding episodes occurred in 19 (24.1%) and 22 (46.8%) patients in the RCA and no-anticoagulation group, respectively (P = .012). The overall citrate accumulation (CA) rate was 5% in the RCA group. Patient mortality was associated with the comorbidity of hypertension, increased serum lactate level, and increased SOFA score. After matching, the filter lifespan was significantly longer in the RCA group than the no-anticoagulation group. With careful monitoring and timely adjustment, RCA most likely was safe and effective for CRRT in hyperlactatemia patients with increased bleeding risk.

SCAI clinical expert consensus statement on the classification of cardiogenic shock: This document was endorsed by the American College of Cardiology (ACC), the American Heart Association (AHA), the Society of Critical Care Medicine (SCCM), and the Society of Thoracic Surgeons (STS) in April 2019

BACKGROUND

The outcome of cardiogenic shock complicating myocardial infarction has not appreciably changed in the last 30 years despite the development of various percutaneous mechanical circulatory support options. It is clear that there are varying degrees of cardiogenic shock but there is no robust classification scheme to categorize this disease state.

METHODS

A multidisciplinary group of experts convened by the Society for Cardiovascular Angiography and Interventions was assembled to derive a proposed classification schema for cardiogenic shock. Representatives from cardiology (interventional, advanced heart failure, noninvasive), emergency medicine, critical care, and cardiac nursing all collaborated to develop the proposed schema.

RESULTS

A system describing stages of cardiogenic shock from A to E was developed. Stage A is "at risk" for cardiogenic shock, stage B is "beginning" shock, stage C is "classic" cardiogenic shock, stage D is "deteriorating", and E is "extremis". The difference between stages B and C is the presence of hypoperfusion which is present in stages C and higher. Stage D implies that the initial set of interventions chosen have not restored stability and adequate perfusion despite at least 30 minutes of observation and stage E is the patient in extremis, highly unstable, often with cardiovascular collapse.

CONCLUSION

This proposed classification system is simple, clinically applicable across the care spectrum from pre-hospital providers to intensive care staff but will require future validation studies to assess its utility and potential prognostic implications.