Relationship between blood lactate and early hepatic dysfunction in acute circulatory failure

Timing of endoscopy in patients with elevated lactate levels and acute upper gastrointestinal bleeding; a retrospective comparative study

BACKGROUND/AIMS

While current guidelines recommend performing endoscopy within 24 h in case of acute upper gastrointestinal bleeding (AUGIB), the precise timing remains an issue of debate. Lactate is an established parameter for risk stratification in a variety of medical emergencies. This study evaluated the predictive ability of elevated lactate levels in identifying patients with UGIB, who may benefit from emergent endoscopy.

METHODS

We retrospectively analyzed all patients with elevated lactate levels, who presented to our emergency department between 01 January 2015 and 31 December 2019 due to suspected AUGIB.

RESULTS

Of 134 included cases, 81.3% had an Charlson comorbidity index of ≥3 and 50.4% presented with shock. Fifteen (11.2%) patients died and mortality rates rose with increasing lactate levels. Emergent endoscopy within 6 h (EE) and non-EE were performed in 64 (47.8%) and 70 (52.2%) patients, respectively. Patients who underwent EE had lower systolic blood pressure (107.6 mmHg vs. 123.2 mmHg; p = 0.001) and received blood transfusions more frequently (79.7% vs 64.3%; p = 0.048), but interestingly need for endoscopic intervention (26.6% vs 20.0%; p = 0.37), rebleeding (17.2% vs. 15.7%; p = 0.82) and mortality (9.4% vs. 11.4%; p = 0.7) did not differ significantly.

CONCLUSION

In conclusion, our findings support the recommendations of current guidelines to perform non-EE after sufficient resuscitation and management of comorbid illnesses.

Emerging concepts in the care of patients with cirrhosis and septic shock

Septic shock impacts approximately 6% of hospitalized patients with cirrhosis and is associated with high rates of morbidity and mortality. Although a number of landmark clinical trials have paved the way for incremental improvements in the diagnosis and management of septic shock in the general population, patients with cirrhosis have largely been excluded from these studies and critical knowledge gaps continue to impact the care of these individuals. In this review, we discuss nuances in the care of patients with cirrhosis and septic shock using a pathophysiology-based approach. We illustrate that septic shock may be challenging to diagnose in this population in the context of factors such as chronic hypotension, impaired lactate metabolism, and concomitant hepatic encephalopathy. Furthermore, we demonstrate that the application of routine interventions such as intravenous fluids, vasopressors, antibiotics, and steroids should be carefully considered among those with decompensated cirrhosis in light of hemodynamic, metabolic, hormonal, and immunologic disturbances. We propose that future research should include and characterize patients with cirrhosis in a systematic manner, and clinical practice guidelines may need to be refined accordingly.

Comparison of Lactate Clearance with Established Risk Assessment Tools in Predicting Outcomes in Acute Upper Gastrointestinal Bleeding

Early risk stratification is mandatory in acute upper gastrointestinal bleeding (AUGIB) to guide optimal treatment. Numerous risk scores were introduced, but lack of practicability led to limited use in daily clinical practice. Lactate clearance is an established risk assessment tool in a variety of diseases, such as trauma and sepsis. Therefore, this study compares the predictive ability of pre-endoscopic lactate clearance and established risk scores in patients with AUGIB at the University Hospital of Cologne. Active bleeding was detected in 27 (25.2%) patients, and hemostatic intervention was performed in 35 (32.7%). In total, 16 patients (15%) experienced rebleeding and 12 (11.2%) died. Initially, lactate levels were elevated in 64 cases (59.8%), and the median lactate clearance was 18.7% (2.7-48.2%). Regarding the need for endoscopic intervention, the predictive ability of Glasgow Blatchford Score, pre-endoscopic Rockall score, initial lactate and lactate clearance did not differ significantly, and their area under the receiver operating characteristic curves were 0.658 (0.560-0.747), 0.572 (0.473-0.667), 0.572 (0.473-0.667) and 0.583 (0.483-0.677), respectively. Similar results were observed in relation to rebleeding and mortality. In conclusion, lactate clearance had comparable predictive ability compared to established risk scores. Further prospective research is necessary to clarify the potential role of lactate clearance as a reliable risk assessment tool in AUGIB.

Evaluation and management of emergencies in the patient with cirrhosis

The approach to and management of critically ill patients is one of the most versatile themes in emergency medicine. Patients with cirrhosis of the liver have characteristics that are inherent to their disease that can condition modification in acute emergency treatment. Pathophysiologic changes that occur in cirrhosis merit the implementation of an analysis as to whether the overall management of a critically ill patient can generally be applied to patients with cirrhosis of the liver or if they should be treated in a special manner. Through a review of the medical literature, the available information was examined, and the evidence found on the special management required by those patients was narratively synthesized, selecting the most representative decompensations within chronic disease that require emergency treatment.

Evaluation and management of emergencies in the patient with cirrhosis

The approach to and management of critically ill patients is one of the most versatile themes in emergency medicine. Patients with cirrhosis of the liver have characteristics that are inherent to their disease that can condition modification in acute emergency treatment. Pathophysiologic changes that occur in cirrhosis merit the implementation of an analysis as to whether the overall management of a critically ill patient can generally be applied to patients with cirrhosis of the liver or if they should be treated in a special manner. Through a review of the medical literature, the available information was examined, and the evidence found on the special management required by those patients was narratively synthesized, selecting the most representative decompensations within chronic disease that require emergency treatment.

Liver cirrhosis affects serum lactate level measurement while assessing disease severity in patients with sepsis

BACKGROUND

Elevated serum lactate is associated with higher mortality in sepsis, whereas liver dysfunction is associated with higher serum lactate levels. We assessed the predictive ability of serum lactate in patients with liver cirrhosis and sepsis.

METHODS

This retrospective study included 12 281 cases of suspected infection with initial serum blood lactate drawn during January 2007-December 2013.

RESULTS

Using one-to-two propensity score matching analysis, 1053 and 2106 septic patients with and without underlying liver cirrhosis, respectively, were successfully matched. Lactate levels of survivors and nonsurvivors were 2.58 and 5.93 mmol/L, respectively, in patients without liver cirrhosis (WLC), 2.96 and 7.29 mmol/L, respectively, in patients with nondecompensated liver cirrhosis (NDLC), and 4.08 and 7.16 mmol/L, respectively, in patients with decompensated liver cirrhosis (DLC). In receiver operating characteristic curve analysis, the sensitivity and specificity for predicting mortality were 0.81 and 0.55, respectively, in the WLC group, 0.85 and 0.45, respectively, in the NDLC group, and 0.86 and 0.33, respectively, in the DLC group, using serum lactate levels >2.0 mmol/L.

CONCLUSIONS

The serum lactate level can be used to predict the severity of sepsis in patients with liver cirrhosis; however, its specificity would be lower at a cutoff of 2.0 mmol/L.

Associations Between Mean Arterial Pressure and Poor ICU Outcomes in Critically Ill Patients With Cirrhosis: Is 65 The Sweet Spot?

OBJECTIVES

Mean arterial pressure is critically important in patients with cirrhosis in the ICU, however, there is limited data to guide therapies and targets.

DESIGN

Retrospective observational study.

SETTING

Tertiary care ICU.

PATIENTS

Two hundred and seventy-three critically ill patients with cirrhosis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We performed a comprehensive time-weighted mean arterial pressure analysis (time-weighted-average-mean arterial pressure and cumulative-time-below various mean arterial pressure-thresholds) during the first 24-hours after ICU admission (median: 25 mean arterial pressure measurements per-patient). Time-weighted-average-mean arterial pressure captures both the severity and duration of hypotension below a mean arterial pressure threshold and cumulative-time-below is the total time spent below a mean arterial pressure threshold. Individual univariable and multivariable logistic regression models were assessed for each time-weighted-average-mean arterial pressure and cumulative-time-below mean arterial pressure threshold (55, 60, 65, 70, and 75 mm Hg) for ICU-mortality. Time-weighted-average-mean arterial pressure: for 1 mm Hg decrease in mean arterial pressure below 75, 70, 65, 60, and 55 mm Hg, the odds for ICU-mortality were 14%, 18%, 26%, 41%, and 74%, respectively (p < 0.01, all thresholds). The association between time-weighted-average-mean arterial pressure and ICU-mortality for each threshold remained significant after adjusting for model for end-stage liver disease-sodium score, mechanical ventilation, vasopressor use, renal replacement therapy, grade 3/4 hepatic encephalopathy, WBC count, and albumin. Cumulative-time-below: odds for ICU-mortality were 4%, 6%, 10%, 12%, and 12% for each-hour spent below 75, 70, 65, 60, and 55 mm Hg, respectively. In the adjusted models, significant associations only remained for mean arterial pressure less than 65 mm Hg (odds ratio, 1.07; 95% CI, 1.00-1.14; p = 0.05) and < 60 mm Hg (odds ratio, 1.10; 95% CI, 1.01-1.18; p = 0.04).

CONCLUSIONS

These data suggest that maintaining a mean arterial pressure of greater than 65 mm Hg may be a reasonable target in patients with cirrhosis admitted to the ICU. However, further prospective randomized trials are needed to determine the optimal mean arterial pressure-targets in this patient population.

Update on diagnosis and management of sepsis in cirrhosis: Current advances

Sepsis and septic shock are catastrophic disease entities that portend high mortality in patients with cirrhosis. In cirrhosis, hemodynamic perturbations, immune dysregulation, and persistent systemic inflammation with altered gut microbiota in the background of portal hypertension enhance the risk of infections and resistance to antimicrobials. Patients with cirrhosis develop recurrent life-threatening infections that progress to multiple organ failure. The definition, pathophysiology, and treatment options for sepsis have been ever evolving. In this exhaustive review, we discuss novel advances in the understanding of sepsis, describe current and future biomarkers and scoring systems for sepsis, and delineate newer modalities and adjuvant therapies for the treatment of sepsis from existing literature to extrapolate the same concerning the management of sepsis in cirrhosis. We also provide insights into the role of gut microbiota in initiation and progression of sepsis and finally, propose a treatment algorithm for management of sepsis in patients with cirrhosis.

Glucose-lowering therapy and cardiovascular outcomes in patients with type 2 diabetes mellitus and acute coronary syndrome

Diabetes is a common comorbidity in patients hospitalized for an acute coronary syndrome event, and prevalence is increasing. Among patients hospitalized with acute myocardial infarction, diabetes can be an independent predictor of mortality and new cardiovascular events; both short- and long-term outcomes are worse for patients with diabetes relative to those without, and undiagnosed diabetes is associated with greater mortality. The impact of glycemic control on cardiovascular outcomes and the best approach to treat hyperglycemia upon hospital admission for acute coronary syndrome in patients with or without known diabetes remain open questions. This review assesses available evidence for hyperglycemia management at the time of admission for acute coronary syndrome and, thereafter, finds that (1) admission plasma glucose plays a role in predicting adverse events, especially in patients with unknown diabetes; (2) glycated haemoglobin is a likely predictor of events in patients with unknown diabetes; and (3) hypoglycemia at the time of acute myocardial infarction hospital admission is an important predictor for mortality in patients with and without diabetes. Whether glucose-targeted insulin and glucose infusion have advantages over glucose-insulin-potassium infusion remains controversial. Evidence for the effect of novel glucose-lowering agents used at the time of an acute cardiovascular event is limited and requires more dedicated studies.

Acid-Base Disturbances in Patients with Asthma: A Literature Review and Comments on Their Pathophysiology

Asthma is a common illness throughout the world that affects the respiratory system function, i.e., a system whose operational adequacy determines the respiratory gases exchange. It is therefore expected that acute severe asthma will be associated with respiratory acid-base disorders. In addition, the resulting hypoxemia along with the circulatory compromise due to heart–lung interactions can reduce tissue oxygenation, with a particular impact on respiratory muscles that have increased energy needs due to the increased workload. Thus, anaerobic metabolism may ensue, leading to lactic acidosis. Additionally, chronic hypocapnia in asthma can cause a compensatory drop in plasma bicarbonate concentration, resulting in non-anion gap acidosis. Indeed, studies have shown that in acute severe asthma, metabolic acid-base disorders may occur, i.e., high anion gap or non-anion gap metabolic acidosis. This review briefly presents studies that have investigated acid-base disorders in asthma, with comments on their underlying pathophysiology.

Serum lactate levels are associated with serum alanine aminotransferase and total bilirubin levels in patients with type 2 diabetes mellitus: A cross-sectional study

AIMS

It was recently reported that lactate acts as a metabolic mediator and rises in the diabetic state, but the physiological effects are as yet poorly understood. The objective of the current study was to evaluate the significance of serum lactate elevation in type 2 diabetes mellitus (T2DM) patients.

METHODS

Fasting serum lactate levels, hematological and inflammatory serum markers and anthropometric parameters, obtained employing bioelectric impedance analysis, were measured in 103 patients with T2DM.

RESULTS

Statistically significant correlations of serum lactate levels with C-reactive peptide, insulin, aspartate aminotransferase, alanine aminotransferase (ALT), serum lipids, total bilirubin, adiponectin, homeostasis model assessment-insulin resistance, body weight, body mass index and body fat (weight or percentage of subcutaneous fat, visceral fat or total body fat), but neither fasting plasma glucose nor HbA1c, were detected. Stepwise regression analysis showed ALT to be independently positively associated with total bilirubin, while being negatively associated with serum lactate levels. Furthermore, serum lactate levels were significantly higher in patients with ALT-predominant liver dysfunction.

CONCLUSION

We found fasting serum lactate elevation in T2DM patients to be associated with the serum levels of ALT and total bilirubin independently of blood glucose control.

TRIAL REGISTRATION

UMIN clinical trials registry (UMIN000029178).

The association of early combined lactate and glucose levels with subsequent renal and liver dysfunction and hospital mortality in critically ill patients

BACKGROUND

The development of renal and liver dysfunction may be accompanied by initially subtle derangements in the gluconeogenetic function. Discrepantly low glucose levels combined with high lactate levels might indicate an impaired Cori cycle. Our objective was to examine the relation between early lactate and glucose levels with subsequent renal and liver dysfunction and hospital mortality in critically ill patients.

METHODS

Over a 4-year period (2011 to 2014), all adult patients admitted to our adult 48-bed teaching hospital intensive care unit (ICU) for at least 12 h were retrospectively analyzed. Lactate and glucose were regularly measured with point-of-care analyzers in all ICU patients. Lactate and glucose measurements were collected from 6 h before to 24 h after ICU admission. Patients with fewer than four lactate/glucose measurements were excluded. Patients received insulin according to a computer-guided control algorithm that aimed at a glucose level <8.0 mmol/L. Renal dysfunction was defined as the development of acute kidney injury (AKI) within 7 days, and liver function was based on the maximal bilirubin in the 7-day period following ICU admission. Mean lactate and mean glucose were classified into quintiles and univariate and multivariate analyses were related with renal and liver dysfunction and hospital mortality. Since glucose has a known U-shaped relation with outcome, we also accounted for this.

RESULTS

We analyzed 92,000 blood samples from 9074 patients (63% males) with a median age of 64 years and a hospital mortality of 11%. Both lactate quintiles (≤1.0; 1.0-1.3; 1.3-1.7; 1.7-2.3; >2.3 mmol/L) and glucose quintiles (≤7.0; 7.0-7.6; 7.6-8.2; 8.2-9.0; >9.0 mmol/L) were related with outcome in univariate analysis (p < 0.001). Acute Physiology and Chronic Health Evaluation (APACHE) IV, lactate, and glucose were associated with renal and liver dysfunction in multivariate analysis (p < 0.001), with a U-shaped relationship for glucose. The combination of the highest lactate quintile with the lowest glucose quintile was associated with the highest rates of renal dysfunction, liver dysfunction, and mortality (p < 0.001) with a significant interaction between lactate and glucose (p ≤ 0.001).

CONCLUSIONS

Abnormal combined lactate and glucose measurements may provide an early indication of organ dysfunction. In critically ill patients a 'normal' glucose with an elevated lactate should not be considered desirable, as this combination is related with increased mortality.

Cardio-haemodynamic assessment and venous lactate in severe dengue: Relationship with recurrent shock and respiratory distress

Background

Dengue can cause plasma leakage that may lead to dengue shock syndrome (DSS). In approximately 30% of DSS cases, recurrent episodes of shock occur. These patients have a higher risk of fluid overload, respiratory distress and poor outcomes. We investigated the association of echocardiographically-derived cardiac function and intravascular volume parameters plus lactate levels, with the outcomes of recurrent shock and respiratory distress in severe dengue.

Methods/Principle findings

We performed a prospective observational study in Paediatric and adult ICU, at the Hospital for Tropical Diseases (HTD), Ho Chi Minh City, Vietnam. Patients with dengue were enrolled within 12 hours of admission to paediatric or adult ICU. A haemodynamic assessment and portable echocardiograms were carried out daily for 5 days from enrolment and all interventions recorded.

102 patients were enrolled; 22 patients did not develop DSS, 48 had a single episode of shock and 32 had recurrent shock. Patients with recurrent shock had a higher enrolment pulse than those with 1 episode or no shock (median: 114 vs. 100 vs. 100 b/min, P = 0.002), significantly lower Stroke Volume Index (SVI), (median: 21.6 vs. 22.8 vs. 26.8mls/m², P<0.001) and higher lactate levels (4.2 vs. 2.9 vs. 2.2 mmol/l, P = 0.001). Higher SVI and worse left ventricular function (higher Left Myocardial Performance Index) on study days 3–5 was associated with the secondary endpoint of respiratory distress. There was an association between the total IV fluid administered during the ICU admission and respiratory distress (OR: 1.03, 95% CI 1.01–1.06, P = 0.001). Admission lactate levels predicted patients who subsequently developed recurrent shock (P = 0.004), and correlated positively with the total IV fluid volume received (rho: 0.323, P = 0.001) and also with admission ALT (rho: 0.764, P<0.001) and AST (rho: 0.773, P<0.001).

Conclusions/Significance

Echo-derived intravascular volume assessment and venous lactate levels can help identify dengue patients at high risk of recurrent shock and respiratory distress in ICU. These findings may serve to, not only assist in the management of DSS patients, but also these haemodynamic endpoints could be used in future dengue fluid intervention trials.

Dengue is a viral illness that can lead to severe and potentially fatal complications. The most common complication is fluid leakage from blood vessels, which can cause low blood pressure or dengue shock syndrome (DSS). The majority of patients recover with simple intravenous fluid replacement, however in approximately 30% of DSS cases, recurrent episodes of shock occur, and these patients have a higher risk of fluid overload, respiratory distress and death. We investigated whether using portable echocardiograms (Echo) in the intensive care unit (ICU) to assess cardiac function and intravascular volume parameters as well as blood lactate levels, can help identify these patients. We found patients who developed recurrent shock had higher heart rates and lower Stroke Volume Index (SVI), and higher lactate levels at enrolment than those with 1 episode or no shock. Higher SVI and worse cardiac function after 3 days in ICU was associated with respiratory distress. Admission lactate levels predicted patients who subsequently developed recurrent shock and correlated positively with the total IV fluid volume received. These results demonstrate that Echo-derived intravascular volume assessment and venous lactate levels can help identify dengue patients at high risk of poor outcomes in the ICU, and could assist in the management of severe dengue.

The association of admission blood glucose level with the clinical picture and prognosis in cardiogenic shock - Results from the CardShock Study

BACKGROUND

Critically ill patients often present with hyperglycemia, regardless of previous history of diabetes mellitus (DM). Hyperglycemia has been associated with adverse outcome in acute myocardial infarction and acute heart failure. We investigated the association of admission blood glucose level with the clinical picture and short-term mortality in cardiogenic shock (CS).

METHODS

Consecutively enrolled CS patients were divided into five categories according to plasma glucose level at the time of enrolment: hypoglycemia (glucose <4.0mmol/L), normoglycemia (4.0-7.9mmol/L), mild (8.0-11.9mmol/L), moderate (12.0-15.9mmol/L), and severe (≥16.0mmol/L) hyperglycemia. Clinical presentation, biochemistry, and short-term mortality were compared between the groups.

RESULTS

Plasma glucose level of 211 CS patients was recorded. Glucose levels were distributed equally between normoglycemia (26% of patients), mild (27%), moderate (19%) and severe (25%) hyperglycemia, while hypoglycemia (2%) was rare. Severe hyperglycemia was associated with higher blood leukocyte count (17.3 (5.8) E9/L), higher lactate level (4.4 (3.3-8.4) mmol/L) and lower arterial pH (7.23 (0.14)) compared with normoglycemia or mild to moderate hyperglycemia (p<0.001 for all). In-hospital mortality was highest among hypoglycemic (60%) and severely hyperglycemic (56%) patients, compared with 22% in normoglycemic group (p<0.01). Severe hyperglycemia was an independent predictor of in-hospital mortality (OR 3.7, 95% CI 1.19-11.7, p=0.02), when adjusted for age, gender, LVEF, lactate, and DM.

CONCLUSIONS

Admission blood glucose level has prognostic significance in CS. Mortality is highest among patients with severe hyperglycemia or hypoglycemia. Severe hyperglycemia is independently associated with high in-hospital mortality in CS. It is also associated with biomarkers of systemic hypoperfusion and stress response.

Hypoxic Hepatitis: A Review and Clinical Update

Hypoxic hepatitis (HH), also known as ischemic hepatitis or shock liver, is characterized by a massive, rapid rise in serum aminotransferases resulting from reduced oxygen delivery to the liver. The most common predisposing condition is cardiac failure, followed by circulatory failure as occurs in septic shock and respiratory failure. HH does, however, occur in the absence of a documented hypotensive event or shock state in 50% of patients. In intensive care units, the incidence of HH is near 2.5%, but has been reported as high as 10% in some studies. The pathophysiology is multifactorial, but often involves hepatic congestion from right heart failure along with reduced hepatic blood flow, total body hypoxemia, reduced oxygen uptake by hepatocytes or reperfusion injury following ischemia. The diagnosis is primarily clinical, and typically does not require liver biopsy. The definitive treatment of HH involves correction of the underlying disease state, but successful management includes monitoring for the potential complications such as hypoglycemia, hyperglycemia, hyperammonemia and hepatopulmonary syndrome. Prognosis of HH remains poor, especially for cases in which there was a delay in diagnosis. The in-hospital mortality rate is >50%, and the most frequent cause of death is the predisposing condition and not the liver injury itself.

Lactate clearance and mortality in septic patients with hepatic dysfunction

BACKGROUND

Serum lactate clearance (LC) during initial resuscitation is a potentially useful prognostic marker in patients with severe sepsis or septic shock. However, it is unclear whether LC is also associated with the outcome in septic patients with hepatic dysfunction that may impair lactate elimination, which may contribute to elevated serum lactate levels or decreased LC.

METHODS

The relationships between LC measured within 6 and 24h after initial resuscitation and hospital mortality were evaluated with multiple logistic regression analysis.

RESULTS

Of 770 patients with severe sepsis or septic shock, 208 (27%) with hepatic dysfunction were included in the analysis. The median LC within 6h in survivors (31.4%) was significantly higher than that of non-survivors (9.3%) (P=.010). In addition, the median LC within 24h was also significantly different between groups (51% vs. 12%, P<.001). Low LCs, defined as less than 10% of clearance, at 6 and 24h were associated with in-hospital mortality. After adjusting for potential confounding factors, low LCs at 6 and 24h remained associated with hospital mortality (adjusted OR 4.940, 95% CI 1.762-13.854 at 6h; adjusted OR 5.997, 95% CI 2.149-16.737 at 24h). However, LC at 24h (area under the curve of 0.704) had higher discriminatory power to predict hospital mortality than LC at 6h (area under the curve of 0.608) (P=.033).

CONCLUSIONS

LC may be useful for predicting outcomes in septic patients with hepatic dysfunction.

The effect of liver disease on lactate normalization in severe sepsis and septic shock: a cohort study

Objective

To describe the effect of liver disease (LD) on lactate clearance during early sepsis resuscitation.

Methods

This is a multicenter randomized clinical trial. An initial lactate >2 mmol/L and subsequent serum lactate measurement within 6 hours were required for inclusion. LD was categorized by two methods: 1) past medical history (PMH) categorized as no LD, mild LD (no Child’s score criteria, but PMH of hepatitis B/C), cirrhosis; and 2) measurable liver dysfunction determined by the liver component of the sequential organ failure assessment (L-SOFA) score as no dysfunction (L-SOFA score 0), mild dysfunction (score 1), moderate-severe dysfunction (score 2 to 4). Primary outcome was the rate of lactate normalization.

Results

One hundred eighty-seven patients were included. When categorized by PMH, 169 patients had no LD, 6 mild LD, and 12 cirrhosis. 63/169 (37%) of patients with no LD achieved lactate normalization, compared to 4/6 (67%) with mild LD, and 1/12 (8%) with cirrhosis (P<0.03). Categorized by L-SOFA score, 59/124 (47%) patients with L-SOFA 0 achieved lactate normalization, compared to 6/31 (19%) with L-SOFA 1, and 3/32 (9%) with L-SOFA 2–4 (P<0.01). Relative lactate clearance [(initial lactate–subsequent lactate)/initial lactate] was lower in patients with more advanced LD by PMH (37.7 vs. 40.4 vs. 21.8, P=0.07), and lower with increasing L-SOFA score (42.0 vs. 30.1 vs. 23.4, P=0.01).

Conclusion

Liver dysfunction was significantly associated with impaired lactate clearance and normalization during the early resuscitation of sepsis.

Monitoring of serum lactate level during cardiopulmonary resuscitation in adult in-hospital cardiac arrest

Introduction

Serum lactate level may correlate with no-flow and low-flow status during cardiac arrest. Current guidelines have no recommended durations for cardiopulmonary resuscitation (CPR) before transition to the next strategy. We hypothesized that the lactate level measured during CPR could be associated with the survival probability and accordingly be useful in estimating the optimal duration for CPR.

Methods

We conducted a retrospective observational study in a single medical centre and included adult patients who had suffered an in-hospital cardiac arrest between 2006 and 2012. We used multivariable logistic regression analysis to study the association of lactate level measured during CPR and outcomes. We used generalized additive models to examine the nonlinear effects of continuous variables and conditional effect plots to visualize the estimated survival probability against CPR duration.

Results

Of the 340 patients included in our analysis, 50 patients (14.7 %) survived to hospital discharge. The mean lactate level was 9.6 mmol/L and mean CPR duration was 28.8 min. There was an inverse near-linear relationship between lactate level and probability of survival to hospital discharge. A serum lactate level <9 mmol/L was positively associated with patient survival to hospital discharge (odds ratio 2.00, 95 % confidence interval 1.01-4.06). The optimal CPR duration may not be a fixed value but depend on other conditions.

Conclusions

Serum lactate level measured during CPR could correlate with survival outcomes. A lactate level threshold of 9 mmol/L may be used as a reference value to identify patients with different survival probabilities and determine the optimal CPR durations.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-1058-7) contains supplementary material, which is available to authorized users.

Assessment of preload and fluid responsiveness in intensive care unit. How good are we?

Early recognition and treatment of acute circulatory failure and tissue hypoperfusion are paramount for improving the odds of survival in critically ill patients. Fluid volume resuscitation is the mainstay intervention in redistributive and hypovolemic shock. Correct identification of a patient who would benefit from fluid administration allows optimization of hemodynamics and avoids ineffective or even deleterious volume expansion that may result in worsening of gas exchange and pulmonary edema in fluid unresponsive patients, in whom inotropic and/or vasopressor support should preferentially be used. The use of dynamic changes in central venous pressure, pulse pressure, and echocardiography for assessment of inferior vena cava diameter variations during respiration allows prediction of fluid volume responsiveness in hemodynamically unstable patients. The use of these bedside approaches and passive leg raising maneuver, which is a reversible and quick fluid volume challenge, allows timely formulation of treatment strategy in patients with shock.

Ischemic hepatitis after percutaneous nephrolitotomy: A case report

INTRODUCTION

Ischemic hepatitis (IH) is the necrosis of the centrilobular hepatocytes of liver and is secondary to liver hypoperfusion in most of the cases. The diagnosis is usually based on biochemical findings due to the absence of symptoms and signs. Although the disease course is often mild, and sometimes is even not diagnosed, the outcome is poor if the etiology of hypotension and liver anoxia is not promptly corrected.

PRESENTATION OF CASE

A 64-year-old patient who underwent percutaneous nephrolithotomy (PNL) for right renal pelvic stone developed acute IH at first postoperative day as a result of hemorrhage related severe hypotension. After restoring hemodynamic parameters, she completely recovered 2 weeks after the operation.

DISCUSSION

IH is a frequent cause of marked serum aminotransferase elevation and most commonly occurs as a result of arterial hypoxemia and insufficient hepatic perfusion. Although no specific treatment of IH exists, stabilizing the hemodynamic parameters of the patient resolves the problem in most of the cases.

CONCLUSION

This case is presented to demonstrate that ischemic hepatitis should be kept in mind if severe hemorrhage occurs during PNL.

Early blood lactate area as a prognostic marker in pediatric septic shock

PURPOSE

We attempted to evaluate whether the early lactate area is useful as an early prognostic marker of mortality in pediatric septic shock patients.

METHODS

We performed a retrospective study of pediatric patients with septic shock who were admitted to the pediatric intensive care unit of Asan Medical Center, Seoul, Korea. Serial arterial lactate levels were obtained immediately and then every 6 h after admission for a total of 24 h. The lactate area (mmol/lh) was defined as the sum of the area under the curve (AUC) of serial lactate levels measured during the 24 h following admission. We compared the lactate-associated parameters as a predictor of mortality.

RESULTS

A total of 65 patients were included in this study, and the overall 28-day mortality of these patients was 26.2%. Survivors compared with non-survivors had an initial lactate level of 3.13 ± 2.79 vs. 6.16 ± 4.87 mmol/l, a lactate clearance of 32.8 ± 63.4 vs. -30.8 ± 75.6%, and a lactate area of 59.7 ± 56.0 vs. 168.0 ± 107.0 mmol/lh (p < 0.05 for all variables). Receiver operating characteristic curves indicated a strong predictive power for the lactate area (AUC = 0.828), which demonstrated the largest AUC in comparison with the AUCs of the initial lactate level (0.699) or the 24-h lactate clearance (0.719). Using multivariate logistic regression analysis, the lactate area was a significant prognostic factor.

CONCLUSION

The early lactate area is a potentially feasible and clinically useful predictor of mortality in pediatric septic shock patients.

Prevalence and characteristics of nonlactate and lactate expressors in septic shock

PURPOSE

The study's objective was to determine the proportion and patient characteristics of patients in vasopressor-dependent septic shock who presented without lactatemia.

METHODS

A retrospective review of patients presenting to an urban tertiary-care emergency department between December 2007 and September 2008 was conducted. Patients with a final diagnosis of septic shock requiring vasopressors were divided, based on initial lactate, to nonlactate expressors (0-2.4 mmol/L), intermediate (2.5-3.9 mmol/L), and high (>4.0 mmol/L) lactate groups.

RESULTS

Among 123 patients with vasopressor-dependent septic shock, 55 (45%) were nonlactate expressors (lactate ≤ 2.4 mmol/L). Acute liver injury, history of liver disease, and presence of bacteremia were associated with elevated lactate.

CONCLUSION

Almost one-half of patients with vasopressor-dependent septic shock did not express lactate on presentation, although a high mortality rate remains in this population. We found a significant association between lactate expressors and liver disease and between lactate expressors and positive blood cultures. The use of lactatemia as the sole indicator of need for additional intravenous fluid or an end point of resuscitation in septic shock may be inadequate.

Hypoxic hepatitis: a challenging diagnosis

Hypoxic hepatitis (HH), one of the most common causes of acute liver injury, has a prevalence of up to 10% of admissions in intensive care units across the world. Inadequate oxygen uptake by the hepatocytes resulting in centrilobular necrosis associated with abnormally raised levels of the serum transaminases (ALT, AST) in patients with clinical history of cardiac, respiratory, or circulatory failures is the key feature of this condition. Abstracts, reviews, case reports, and research letters from various sources such as Pubmed, Proquest, Ovid, Google Scholar, and ISI Web of Knowledge dating from 1970 to 2011 were read and analyzed thoroughly. A study of 100 patients with HH, carried out from 2009 to 2010 at Tongji Hospital of Tongji University, Shanghai, People's Republic of China, is also documented. The contributing factors leading to HH are passive congestion, ischemia, and arterial hypoxemia of the liver. Ischemia/reperfusion injury also has a major role in HH. Some of its complications are spontaneous hypoglycemia, a high level of serum ammonia, and respiratory insufficiency due to hepatopulmonary syndrome. The therapy of HH lies mainly in the treatment of the main underlying causes, and this leads to the successful reversion of HH. The aim of this review is to present a simplified concept about the etiology, pathophysiology, mechanism, clinical manifestations, diagnosis, and treatment of HH.

Initial lactate level and mortality in septic shock patients with hepatic dysfunction

An elevated serum lactate level is associated with morbidity and mortality in patients with severe sepsis and septic shock. In patients with hepatic dysfunction, however an elevated serum lactate level may be due to either impaired lactate clearance or excessive production. Thus, we evaluated whether the initial serum lactate level was also associated with mortality in septic shock patients with hepatic dysfunction. A retrospective observational study enrolled 307 patients with septic shock admitted to the intensive care unit (ICU) between May 2007 and July 2009. Hepatic dysfunction was defined as a serum total bilirubin > 34.2 micromol/l (2 mg/dl). Selected patients were divided into high (> or = 4 mmol/l) and low (< 4 mmol/l) lactate groups, according to the initial serum lactate level. Of 307 patients with septic shock, 118 (38%) patients with hepatic dysfunction were eligible for this study. The median lactate levels were 5.9 (interquartile range 4.7 to 9.0) and 2.6 (interquartile range 1.7 to 3.2) mmol/l for the high and low lactate groups respectively (P < 0.001). The initial serum lactate level was strongly associated with in hospital mortality in a univariate analysis (P < 0.001). After adjusting for potential confounding factors, the initial serum lactate level remained significantly associated with in-hospital mortality (odds ratio 1.281, 95% confidence interval 1.097 to 1.496, P = 0.002). In conclusion, the serum lactate level could be useful in predicting the outcome of patients with septic shock regardless of hepatic dysfunction.

Low central venous oxygen saturation in haemodynamically stabilized trauma patients is associated with poor outcome

BACKGROUND

Central venous oxygen saturation (ScvO(2)) is suggested to reflect the adequacy of oxygen delivery, and the main objective of the present study was to determine whether ScvO(2) is associated with outcome in haemodynamically stabilized trauma patients.

METHODS

Haemodynamically unstable trauma patients receiving a central venous line within 1 h of admission were eligible for inclusion in this prospective observational study. The mean arterial pressure (MAP), lactate and ScvO(2) were recorded at inclusion and every 6 h for 36 h or until lactate was <2.0 mmol/l and ScvO(2) was >75% in two consecutive measurements. Patients with a MAP of ≥70 mmHg were considered to be haemodynamically stabilized. The outcome measure was complications defined as infections, delta sequential organ failure assessment score of >0, and mortality.

RESULTS

Fifty patients with a median new injury severity score of 27 (17-34) were analysed. Complications occurred in 33 patients. An association between ScvO(2) following resuscitation to MAP ≥70 mmHg and complications was detected with an odds ratio of 0.94 (95% confidence interval; 0.89-0.99). This association was also significant when adjusted for injury severity. The result implies that a low ScvO(2) value is associated with more complications. The optimal cut-off for ScvO(2) to discriminate between patients who did or did not develop complications was found to be 66.5% (56-86%).

CONCLUSIONS

These data suggest that low ScvO(2) in haemodynamically stabilized patients is associated with a poor outcome and that ScvO(2) represents a potential endpoint of resuscitation in trauma patients.

Hypoxic hepatitis in critically ill patients: incidence, etiology and risk factors for mortality

PURPOSE

Hypoxic hepatitis may be induced by hemodynamic instability or arterial hypoxemia in critically ill patients. We investigated the incidence, etiology, association with systemic ischemic injury and risk factors for mortality in this population.

METHODS

Retrospective analysis of patients with hypoxic hepatitis admitted to a multidisciplinary intensive care unit (ICU) of a university hospital. Hypoxic hepatitis was defined as the existence of a compatible clinical setting (cardiocirculatory failure or arterial hypoxemia) and aminotransferase levels higher than 1000 IU/L.

RESULTS

During the 8-year study period, 182 out of the 7674 patients admitted presented hypoxic hepatitis (2.4%). The most common cause was septic shock. The rate of in-hospital mortality in hypoxic hepatitis was 61.5% (112 patients), and was higher in patients with septic shock (83.3%) and cardiac arrest (77.7%). Ischemic pancreatitis (25.6%), rhabdomyolysis (41.2%) and renal failure (67.2%) were common in these patients. Risk factors of mortality were prolonged INR (p = 0.005), need for renal replacement therapy (p = 0.001) and septic shock (p = 0.005).

CONCLUSIONS

Hypoxic hepatitis was not a rare condition, and was frequently accompanied by multiorgan injury, with high mortality. Risk factors for increased mortality were prolonged INR, need for renal replacement therapy, and septic shock.

The role of serum lactate in the acute care setting

Acute care services are increasingly faced with the double burden of high patient acuity and limited resources. Early identification of patients who are sick or who have the potential to deteriorate rapidly is crucial so that these resources may be allocated to those in greatest need. Traditional measures of illness and end points of resuscitation, such as vital signs, often fail to identify occult hypoperfusion with certain disease processes associated with high morbidity and mortality. Thus, biochemical markers that may predict illness earlier are becoming more relevant. We present a review of the evidence behind use of the serum lactate level in this setting.

Blood lactate monitoring in critically ill patients: a systematic health technology assessment

OBJECTIVE

To decide whether the use of blood lactate monitoring in critical care practice is appropriate. We performed a systematic health technology assessment as blood lactate monitoring has been implemented widely but its clinical value in critically ill patients has never been evaluated properly.

DATA SOURCE

PubMed, other databases, and citation review.

STUDY SELECTION

We searched for lactate combined with critically ill patients as the target patient population. Two reviewers independently selected studies based on relevance for the following questions: Does lactate measurement: 1) perform well in a laboratory setting? 2) provide information in a number of clinical situations? 3) relate to metabolic acidosis? 4) increase workers' confidence? 5) alter therapeutic decisions? 6) result in benefit to patients? 7) result in similar benefits in your own setting? 8) result in benefits which are worth the extra costs?

DATA EXTRACTION AND SYNTHESIS

We concluded that blood lactate measurement in critically ill patients: 1) is accurate in terms of measurement technique but adequate understanding of the (an)aerobic etiology is required for its correct interpretation; 2) provides not only diagnostic but also important prognostic information; 3) should be measured directly instead of estimated from other acid-base variables; 4) has an unknown effect on healthcare workers' confidence; 5) can alter therapeutic decisions; 6) could potentially improve patient outcome when combined with a treatment algorithm to optimize oxygen delivery, but this has only been shown indirectly; 7) is likely to have similar benefits in critical care settings worldwide; and 8) has an unknown cost-effectiveness.

CONCLUSIONS

The use of blood lactate monitoring has a place in risk-stratification in critically ill patients, but it is unknown whether the routine use of lactate as a resuscitation end point improves outcome. This warrants randomized controlled studies on the efficacy of lactate-directed therapy.

Hypoxic liver injury

Hypoxic liver injury is defined as a massive, but transient, increase in serum transaminase levels due to an imbalance between hepatic oxygen supply and demand in the absence of other acute causes of liver damage. It typically occurs in elderly individuals with right-sided congestive heart failure and low cardiac output. Precipitating factors include arrhythmias or pulmonary edema. Symptoms include weakness, shortness of breath, and right upper quadrant pain. Less commonly, hypoxic liver injury is seen in patients with severe hypoxemia or septic shock. Characteristically, the transaminase level is elevated 20-fold but normalizes rapidly over several days. Imaging studies reveal hypoechoic or hypodense lesions that resolve completely with reversal of the initiating event. Treatment and prognosis depend on the underlyIng disease.

Prognostic implications of hyperlactatemia, multiple organ failure, and systemic inflammatory response syndrome in patients with acetaminophen-induced acute liver failure

OBJECTIVE

Hyperlactatemia has been suggested as a prognostic marker in acetaminophen-induced fulminant hepatic failure, and a modification of the King's College Hospital criteria to incorporate arterial lactate measurements has recently been proposed. The aims of the present study were to further evaluate arterial lactate as a prognostic marker in acetaminophen-induced fulminant hepatic failure and to analyze its relationship to known causes of hyperlactatemia such as multiple organ failure and inflammation.

DESIGN

Data were collected early after admission and again at the time of onset of grade 3-4 hepatic encephalopathy from acetaminophen-induced fulminant hepatic failure. Multiple organ failure and inflammatory response were assessed by the sequential organ failure assessment (SOFA) score and manifestation of the severe inflammatory response syndrome (SIRS), respectively.

SETTING

A specialized liver intensive care unit at a tertiary liver center.

PATIENTS

One hundred and one consecutive patients with acetaminophen-induced fulminant hepatic failure and grade 3-4 hepatic encephalopathy.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Arterial lactate was higher in nonsurvivors than in survivors both early after admission (9.8 +/- 6.5 mmol/L vs. 5.2 +/- 4.2 mmol/L, p = .00004) and at the time of onset of hepatic encephalopathy (6.9 +/- 5.6 mmol/L vs. 3.2 +/- 2.0 mmol/L, p < .00001). At both time points, arterial lactate significantly correlated with SOFA score and the number of SIRS components fulfilled. Applying the lactate modification of the King's College Hospital criteria increased their sensitivity but reduced their specificity to <50%.

CONCLUSIONS

The study confirmed arterial lactate as a prognostic marker in acetaminophen-induced fulminant hepatic failure. Arterial lactate correlated with SOFA score and with the number of SIRS components fulfilled. The lactate modification of the King's College Hospital criteria showed no obvious advantages over the existing selection criteria.

Serial lactate determinations for prediction of outcome after cardiac arrest

We investigated the relationship between lactate clearance and outcome in patients surviving the first 48 hours after cardiac arrest. We conducted the study in the emergency department of an urban tertiary care hospital. We analyzed the data for all 48-hour survivors after successful resuscitation from cardiac arrest during a 10-year period. Serial lactate measurements, demographic data, and key cardiac arrest data were correlated to survival and best neurologic outcome within 6 months after cardiac arrest. Parameters showing significant results in univariate analysis were tested for significance in a logistic regression model. Of 1502 screened patients, 394 were analyzed. Survivors (n = 194, 49%) had lower lactate levels on admission (median, 7.8 [interquartile range, 5.4-10.8] vs 9 [6.6-11.9] mmol/L), after 24 hours (1.4 [1-2.5] vs 1.7 [1.1-3] mmol/L), and after 48 hours (1.2 [0.9-1.6] vs 1.5 [1.1-2.3] mmol/L). Patients with favorable neurologic outcome (n = 186, 47%) showed lower levels on admission (7.6 [5.4-10.3] vs 9.2 [6.7-12.1] mmol/L) and after 48 hours (1.2 [0.9-1.6] vs 1.5 [1-2.2] mmol/L). In multivariate analysis, lactate levels at 48 hours were an independent predictor for mortality (odds ratio [OR]: 1.49 increase per mmol/L, 95% confidence interval [CI]: 1.17-1.89) and unfavorable neurologic outcome (OR: 1.28 increase per mmol/L, 95% CI: 1.08-1.51). Lactate levels higher than 2 mmol/L after 48 hours predicted mortality with a specificity of 86% and poor neurologic outcome with a specificity of 87%. Sensitivity for both end points was 31%. Lactate at 48 hours after cardiac arrest is an independent predictor of mortality and unfavorable neurologic outcome. Persisting hyperlactatemia over 48 hours predicts a poor prognosis.

Serum lactate, not base deficit, rapidly predicts survival after major burns

BACKGROUND

Clinical studies document correlation of serum lactate and base deficit with mortality in trauma and sepsis. No study of the prognostic value of these two serum markers has been reported in burn injury.

METHODS

Resuscitation data from 49 patients admitted to the adult Burn ICU were analyzed. Lactate and base deficit were analyzed upon admission and every 2h during the initial 48 h after admission. Resuscitation was managed per standard routine, blinded to these data, guided by the Parkland formula. Initial statistical analysis with Cox's regression model was used to determine the relationship between survival, resuscitation parameters, and demographics. Then, a logistic regression was used to determine if any of these variables were quickly predictive (initial values) of the risk of death.

RESULTS

Two variables were predictive of mortality by the Cox regression model: (1) serum lactate value and (2) patient age. Furthermore, analysis by logistic regression revealed that the initial serum lactate value was separately predictive of mortality.

CONCLUSION

In this study, serum lactate but not base deficit, was a predictor of mortality following major burns. Moreover, initial serum lactate values were also predictive of mortality separately.

Blood lactate as an early predictor of outcome in paracetamol-induced acute liver failure: a cohort study

BACKGROUND

Although the King's College Hospital (KCH) selection criteria for emergency liver transplantation in paracetamol-induced acute liver failure are widely used, strategies to improve sensitivity and facilitate earlier transplantation are required. We investigated the use of arterial blood lactate measurement for the identification of transplantation candidates.

METHODS

In a single-centre study, we measured arterial blood lactate early (median 4 h) and after fluid resuscitation (median 12 h) in patients admitted to a tertiary-referral intensive-care unit. Threshold values that best identified individuals likely to die without transplantation were derived in a retrospective initial sample of 103 patients with paracetamol-induced acute liver failure and applied to a prospective validation sample of 107 patients. Predictive value and speed of identification were compared with those of KCH criteria.

FINDINGS

In the initial sample, median lactate was significantly higher in non-surviving patients than in survivors both in the early samples (8.5 [range 1.7--21.0] vs 1.4 [0.53--7.9] mmol/L, p<0.0001) and after fluid resuscitation (5.5 [1.3--18.6] vs 1.3 [0.26--3.2], p<0.0001). Applied to the validation sample, a threshold value of 3.5 mmol/L early after admission had sensitivity 67%, specificity 95%, positive likelihood ratio 13, and negative likelihood ratio 0.35; the corresponding values for a threshold of 3.0 mmol/L after fluid resuscitation were 76%, 97%, 30, and 0.24. Combined early and postresuscitation lactate concentrations had similar predictive ability to KCH criteria but identified non-surviving patients earlier (4 [3--13] vs 10 [3.5--19.5] h, p=0.01). Addition of postresuscitation lactate concentration to KCH criteria increased sensitivity from 76% to 91% and lowered negative likelihood ratio from 0.25 to 0.10.

INTERPRETATION

Arterial blood lactate measurement rapidly and accurately identifies patients who will die from paracetamol-induced acute liver failure. Its use could improve the speed and accuracy of selection of appropriate candidates for transplantation.

Liver and intestinal lactate metabolism in patients with acute hepatic failure undergoing liver transplantation

OBJECTIVE

To determine the relative contribution of the gastrointestinal tract and the liver in lactate metabolism in patients with acute liver failure (ALF) and the effect of liver transplantation on this. We hypothesized that the liver and gut are net producers of lactate in ALF and that this is reversed after liver transplantation.

SETTING

A university-affiliated specialist liver transplant operating theater.

SUBJECTS

Eleven patients with ALF undergoing liver transplantation.

MEASUREMENTS AND INTERVENTIONS

After ethical approval, 11 patients with ALF listed for orthotopic hepatic transplantation were studied. Whole blood was analyzed for lactate concentration from radial artery (RA) catheter, portal vein (PV), and hepatic vein (HV) during the dissection phase and was repeated postreperfusion of the liver graft. Gradients across the gut and the liver were calculated to see if there was net production or consumption.

RESULTS

HV lactate was significantly higher than arterial (p =.028) in patients with ALF before liver transplantation, suggesting splanchnic production of lactate. Total splanchnic lactate gradient (HV-RA) is positive in ALF. Both the gut (PV-RA) and the liver (HV-PV) were net producers of lactate. After liver transplantation, hepatic venous lactate falls below arterial levels but not significantly. The gradient across the gut (PV-RA) remained positive, but the transhepatic gradient (HV-PV) became significantly negative, showing consumption by the graft (p =.021). The magnitude of lactate consumption after transplantation correlated positively with portal venous lactate concentration (p =.029) and inversely with graft cold ischemic time (p =.007).

CONCLUSION

The liver is a net producer of lactate in patients with ALF and an elevated whole blood lactate. After liver transplantation, the graft becomes a consumer of lactate as shown by the negative lactate gradient. The degree of consumption is dependent on portal venous lactate concentration and cold ischemic time.