Liver dysfunction in critical illness

Early versus late parenteral nutrition in term and late preterm infants: a randomised controlled trial

BACKGROUND

There is limited evidence regarding the optimal time to commence parenteral nutrition (PN) in term and late preterm infants.

DESIGN

Single-centre, non-blinded, exploratory randomised controlled trial.

SETTING

A level-3 neonatal unit in a stand-alone paediatric hospital.

PATIENTS

Infants born ≥34 weeks of gestation and ≤28 days, who needed PN. Eligible infants were randomised on day 1 or day 2 of admission.

INTERVENTIONS

Early (day 1 or day 2 of admission, N=30) or late (day 6 of admission, N=30) PN.

MAIN OUTCOME MEASURES

Plasma phenylalanine and F2-isoprostane levels on day 4 and day 8 of admission. Secondary outcomes were amino-acid and fatty-acid profiles on day 4 and day 8, and clinical outcomes.

RESULTS

The postnatal age at randomisation was similar between the groups (2.3 (SD 0.8) vs 2.3 (0.7) days, p=0.90). On day 4, phenylalanine levels in early-PN infants were higher than in late-PN (mean (SD) 62.9 (26.7) vs 45.5 (15.3) µmol/L; baseline-adjusted percentage difference 25.8% (95% CI 11.6% to 39.9%), p<0.001). There was no significant difference in phenylalanine levels between the two groups on day 8. There was no significant difference between the groups for F2-isoprostane levels on day 4 (early-PN mean (SD) 389 (176) vs late-PN 419 (291) pg/mL; baseline-adjusted percentage difference: -4.4% (95% CI -21.5% to 12.8%) p=0.62) and day 8 (mean (SD) 305 (125) vs 354 (113) pg/mL; adjusted mean percentage difference -16.1 (95% CI -34.1 to 1.9) p=0.09).Postnatal growth restriction for weight was less severe in the early-PN group (change in weight z-score from baseline to discharge: -0.6 (0.6) vs -1.0 (0.6); p=0.02). The incidence of hyperglycaemia was greater in the early-PN group (20/30 (66.7%) vs 11/30 (36.7%), p=0.02).

CONCLUSIONS

The timing of the commencement of PN did not seem to affect the degree of oxidative stress in critically ill term and late preterm infants. The effect of transiently high plasma phenylalanine with early PN on clinical outcomes requires further investigation.

TRIAL REGISTRATION NUMBER

ACTRN12620000324910.

Coronavirus Disease 2019 and Liver Injury: A Retrospective Analysis of Hospitalized Patients in New York City

BACKGROUND AND AIMS

Coronavirus disease 2019 (COVID-19) is a global threat, affecting more than 100 million people and causing over 2 million deaths. Liver laboratory test abnormalities are an extrapulmonary manifestation of COVID-19, yet characterization of hepatic injury is incomplete. Our objective was to further characterize and identify causes of liver injury in patients with COVID-19.

METHODS

We conducted a retrospective cohort study of 551 patients hospitalized with COVID-19 at NewYork-Presbyterian Hospital/Columbia University Irving Medical Center between March 1, 2020 and May 31, 2020. We analyzed patient demographics, liver laboratory test results, vital signs, other relevant test results, and clinical outcomes (mortality and intensive care unit admission).

RESULTS

Abnormal liver laboratory tests were common on hospital admission for COVID-19 and the incidence increased during hospitalization. Of those with elevated serum alanine aminotransferase and/or alkaline phosphatase activities on admission, 58.2% had a cholestatic injury pattern, 35.2% mixed, and 6.6% hepatocellular. Comorbid liver disease was not associated with outcome; however, abnormal direct bilirubin or albumin on admission were associated with intensive care unit stay and mortality. On average, patients who died had greater magnitudes of abnormalities in all liver laboratory tests than those who survived. Ischemic hepatitis was a mechanism of severe hepatocellular injury in some patients.

CONCLUSIONS

Liver laboratory test abnormalities are common in hospitalized patients with COVID-19, and some are associated with increased odds of intensive care unit stay or death. Severe hepatocellular injury is likely attributable to secondary effects such as systemic inflammatory response syndrome, sepsis, and ischemic hepatitis.

Evaluating mortality and recovery of extreme hyperbilirubinemia in critically ill patients by phasing the peak bilirubin level: A retrospective cohort study

Background

Hyperbilirubinemia is a devastating complication in patients admitted to an intensive care unit (ICU). The sequential organ failure assessment (SOFA) score classifies hyperbilirubinemia without further detailed analyses for bilirubin increase above 12 mg/dL. We evaluated whether the level of bilirubin increase in patients with extreme hyperbilirubinemia (total bilirubin ≥ 12 mg/dL) affects and also helps estimate mortality or recovery.

Methods

A retrospective cohort analysis comprising 427 patients with extreme hyperbilirubinemia admitted to the ICU of Samsung Medical Center, Seoul, Korea between 2011 and 2015 was conducted. Extreme hyperbilirubinemia was classified into four grades: grade 1 (12–14.9 mg/dL), grade 2 (15–19.9 mg/dL), grade 3 (20–29.9 mg/dL), and grade 4 (≥ 30 mg/dL). These grades were then assessed for their association with hospital mortality and recovery from hyperbilirubinemia to SOFA grade (point) 2 or below (total bilirubin < 6 mg/dL). The influences of various factors, some of which caused extreme hyperbilirubinemia, while others induced bilirubin recovery, were assessed.

Results

A total of 427 patients (mean age: 59.8 years, male: 67.0%) were evaluated, and the hospital mortality for these patients was very high (76.1%). Extreme hyperbilirubinemia was observed in 111 (grade 1, 26.0%), 99 (grade 2, 23.2%), 131 (grade3, 30.7%), and 86 (grade 4, 20.1%) patients with mortality rates of 62.2%, 71.7%, 81.7%, and 90.7%, respectively (p < 0.001). The peak bilirubin value correlated with the mortality (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.04–1.15, p < 0.001). Compared to those with grade 1 extreme hyperbilirubinemia, the mortality rate gradually increased as the grade increased (OR [95% CI]: 1.92 [0.70–5.28], 3.55 [1.33–9.48], and 12.47 [3.07–50.59] for grades 2, 3 and 4, respectively). The main causes of extreme hyperbilirubinemia were infection including sepsis and hypoxic hepatitis. The recovery from hyperbilirubinemia was observed in 110 (25.8%) patients. Mortality was lower for those who recovered from hyperbilirubinemia than for those who did not (29.1% vs. 92.4%, p < 0.001). The favorable factors of bilirubin recovery were albumin and ursodeoxycholic acid (UDCA).

Conclusions

This study determined that the level of extreme hyperbilirubinemia is an important prognostic factor in critically ill patients. We expect the results of this study to help predict the clinical course of and determine the optimal treatment for extreme hyperbilirubinemia.

Liver-lung interactions in acute respiratory distress syndrome

Patients with liver diseases are at high risk for the development of acute respiratory distress syndrome (ARDS). The liver is an important organ that regulates a complex network of mediators and modulates organ interactions during inflammatory disorders. Liver function is increasingly recognized as a critical determinant of the pathogenesis and resolution of ARDS, significantly influencing the prognosis of these patients. The liver plays a central role in the synthesis of proteins, metabolism of toxins and drugs, and in the modulation of immunity and host defense. However, the tools for assessing liver function are limited in the clinical setting, and patients with liver diseases are frequently excluded from clinical studies of ARDS. Therefore, the mechanisms by which the liver participates in the pathogenesis of acute lung injury are not totally understood. Several functions of the liver, including endotoxin and bacterial clearance, release and clearance of pro-inflammatory cytokines and eicosanoids, and synthesis of acute-phase proteins can modulate lung injury in the setting of sepsis and other severe inflammatory diseases. In this review, we summarized clinical and experimental support for the notion that the liver critically regulates systemic and pulmonary responses following inflammatory insults. Although promoting inflammation can be detrimental in the context of acute lung injury, the liver response to an inflammatory insult is also pro-defense and pro-survival. A better understanding of the liver–lung axis will provide valuable insights into new diagnostic targets and therapeutic strategies for clinical intervention in patients with or at risk for ARDS.

Cholestatic Liver Diseases: A Primer for Generalists and Subspecialists

Cholestasis describes impairment in bile formation or flow which can manifest clinically with fatigue, pruritus, and jaundice. The differential diagnosis of cholestatic liver diseases is broad, and the etiologies of cholestasis vary in the anatomical location of the defect and acuity of presentation. Cholestasis may occur in a variety of clinical scenarios. Therefore, it is important for a diverse audience with varied clinical practices to have a basic understanding of manifestations of cholestatic liver diseases.

The role of bilirubin to albumin ratio as a predictor for mortality in critically ill patients without existing liver or biliary tract disease

Background:

Hyperbilirubinemia and hypoalbuminemia are frequently appeared and associated with poor prognosis in critically ill patients. We aim to evaluate the association between the bilirubin to albumin ratio and prognosis in intensive care unit (ICU) patients.

Methods:

This was a retrospective study of 731 patients who were admitted to the medical intensive care unit (MICU) at a tertiary-care center from July 2015 to September 2017. We analyzed the bilirubin to albumin ratio on admission to the MICU, including clinical characteristics and other examinations.

Results:

The overall 28-day survival of MICU patients was 69.1%. On univariate analysis, Acute Physiology and Chronic Health Evaluation (APACHE) II score (P<0.001), Sequential Organ Failure Assessment score (P<0.001), Simplified Acute Physiology Score II score (P<0.001), Creactive protein (P=0.015), and bilirubin/albumin ratio (P<0.001) were associated with mortality of ICU patients. The receiver operating characteristic curves for ICU patients mortality between bilirubin to albumin ratio and APACHE II score were not statistically significant (P=0.282). On multivariate analysis, higher APACHE II score (hazard ratio [HR], 1.05; 95% CI, 1.03 to 1.06; P<0.001) and bilirubin to albumin ratio (HR, 1.65; 95% CI, 1.23 to 2.20; P=0.001) were independently related to the ICU patient mortality.

Conclusions:

A higher bilirubin to albumin ratio was related to the unfavorable prognosis and mortality in critically ill patients.

Plasma biomarkers to study mechanisms of liver injury in patients with hypoxic hepatitis

BACKGROUND & AIMS

Hypoxic hepatitis is a clinical condition precipitated by prolonged periods of oxygen deprivation to the liver. It can have several underlying causes. Despite its prevalence in critically ill patients, which can reach upwards of 10%, very little is known about the mechanisms of injury. Thus, we set out to measure previously identified circulating biomarkers in an attempt to describe mechanisms of injury following hypoxic hepatitis.

METHODS

Plasma from patients diagnosed with hypoxic hepatitis was collected for this study. Biomarkers of hepatocellular injury, mitochondrial damage and cell death were measured. These results were compared against results obtained from well-characterized acetaminophen overdose patients.

RESULTS

At peak injury, ALT measured 4082±606 U/L and gradually decreased over 5 days, corresponding to the clinically observed pattern of hypoxic hepatitis. Levels of GDH showed a similar pattern, but neither ALT nor GDH were significantly higher in these patients than in acetaminophen patients. Plasma levels of DNA fragments mimicked hepatocellular injury as measured by ALT and miRNA-122. Interestingly, we found a significant increase in caspase-cleaved cytokeratin-18; however, the full-length form greatly exceeded the cleaved form at the time of maximum injury (45837±12085 vs 2528±1074 U/L). We also found an increase in acHMGB1 at later time points indicating a possible role of inflammation, but cytokine levels at these times were actually decreased relative to early time points.

CONCLUSIONS

The mechanism of injury following hypoxic hepatitis involves mitochondrial damage and DNA fragmentation. Importantly, necrosis, rather than apoptosis, is the main mode of cell death.

Model for End-stage Liver Disease excluding INR (MELD-XI) score in critically ill patients: Easily available and of prognostic relevance

Purpose

MELD-XI, an adapted version of Model for End-stage Liver Disease (MELD) score excluding INR, was reported to predict outcomes e.g. in patients with acute heart failure. We aimed to evaluate MELD-XI in critically ill patients admitted to an intensive care unit (ICU) for prognostic relevance.

Methods

A total of 4381 medical patients (66±14 years, 2862 male) admitted to a German ICU between 2004 and 2009 were included and retrospectively investigated. Admission diagnoses were e.g. myocardial infarction (n = 2034), sepsis (n = 694) and heart failure (n = 688). We divided our patients in two cohorts basing on their MELD-XI score and evaluated the MELD-XI score for its prognostic relevance regarding short-term and long-term survival. Optimal cut-offs were calculated by means of the Youden-Index.

Results

Patients with a MELD-XI score >12 had pronounced laboratory signs of organ failure and more comorbidities.

MELD-XI >12 was associated with an increase in short-term (27% vs 6%; HR 4.82, 95%CI 3.93–5.93; p<0.001) and long-term (HR 3.69, 95%CI 3.20–4.25; p<0.001) mortality. In a univariate Cox regression analysis for all patients MELD-XI was associated with increased long-term mortality (changes per score point: HR 1.06, 95%CI 1.05–1.07; p<0.001) and remained to be associated with increased mortality after correction in a multivariate regression analysis for renal failure, liver failure, lactate concentration, blood glucose concentration, oxygenation and white blood count (HR 1.04, 95%CI 1.03–1.06; p<0.001). Optimal cut-off for the overall cohort was 11 and varied remarkably depending on the admission diagnosis: myocardial infarction (9), pulmonary embolism (9), cardiopulmonary resuscitation (17) and pneumonia (17). We performed ROC-analysis and compared the AUC: SAPS2 (0.78, 95%CI 0.76–0.80; p<0.0001) and APACHE (0.76, 95%CI 0.74–0.78; p<0.003) score were superior to MELD-XI (0.71, 95%CI 0.68–0.73) for prediction of mortality.

Conclusions

The easily calculable MELD-XI score is a robust and reliable tool to predict both intra-ICU and long-term mortality in critically ill medical patients admitted to an ICU. Optimal cut-off values for MELD-XI scores seem to depend on the primary disease and need to be validated in future prospective studies. Compared to SAPS2 and APACHE score, MELD-XI lacks precision but might have comparable and even additive value, as it is easily available and independent of subjective values.

[Acute liver ischaemia after gastro-oesophageal variceal bleeding]

INTRODUCTION

Variceal upper gastrointestinal bleeding (UGIB) can trigger acute hypoxic hepatitis (AHH). The aim of this study was to analyse the incidence, associated risk factors and mortality of AHH after variceal UGIB.

PATIENTS AND METHODS

Retrospective study of cirrhotic patients with variceal UGIB, classified into 2 groups according to the development of AHH. AHH was diagnosed when AST and ALT reached levels 10 times above the upper limit of normal, after ruling out other causes of hepatitis. The standard initial treatment consisted of haemodynamic support, emergency endoscopy with rubber band ligation, somatostatin and antibiotics. In the case of failure of primary haemostasis, a transjugular intrahepatic portosystemic shunt (TIPS) was implanted. Both groups (AHH and non-AHH) were compared.

RESULTS

Sixty-eight cirrhotic patients with variceal UGIB admitted to the gastroenterology department of Hospital Ramón y Cajal between January 2007 and March 2012 were analysed. Eleven of these patients (16.2%) developed AHH. Univariate analysis showed the following items as risk factors: diabetes (OR: 7.5; CI: 1.9-29), shock (OR: 8.5; CI: 2.06-34) and persistent bleeding (OR: 9.0, CI: 1.6-49, P=.03). However, multivariate analysis confirmed only diabetes (OR: 8.61; CI: 1.4-52.5) and shock (OR: 7.58; CI: 1.26-45.51) as risk factors. Mortality rate in the AHH group was 45%, compared to 10.5% in the non-HAA group (P=.012).

CONCLUSIONS

AHH after variceal UGIB occurred in 16.2% of cirrhotic patients and was associated with a poorer prognosis, with a mortality rate of 45%. Our findings suggest that diabetes and shock are risk factors for the development of AHH. Early identification of at-risk patients could therefore help prevent AHH.

Differences in Liver Impairment Between Adults and Children with Dengue Infection

Dengue infection (DI) is a major vector-borne disease in southeast Asia and an important cause of morbidity. The complications such as hepatic impairment are common, and because the physiology of the liver differs between children and adults, the DI-associated liver impairments might be expected to differ as well. This study aims to compare the differences in liver impairment between adults and children with DI. We retrospectively studied 158 adults and 79 children with serologically confirmed DI admitted to the Bangkok Hospital for Tropical Diseases from 2008 to 2012. In total, 93% of adults and 87% of children exhibited abnormal liver enzyme levels during hospitalization. Overall, 76 (42.4%) adults and 16 (20.3%) children had dengue hemorrhagic fever (DHF). Compared with children, adults with dengue fever (DF) presented a significantly higher incidence of liver function impairment (alanine transaminase [ALT] > 2 × upper limit of normal [ULN]) (47.1% versus 25.5%), hepatitis (ALT > 4 × ULN) (29.4% versus 12.8%), and severe hepatitis (aspartate transaminase [AST]/ALT > 10 × ULN) (16.5% versus 4.3%). Children with DHF showed a significantly higher incidence of liver function impairment due to AST derangement than did adults (100% versus 73%). There were no differences in the total bilirubin, albumin, or total protein levels between adults and children. Liver enzymes normalized significantly more slowly in adults, and AST recovery was faster than ALT. In conclusion, liver function impairment was more common among adults than children with DF. As the severity progressed to DHF, liver injury became more common in children.

Epstein-Barr Virus Infection Mimicking Drug-Induced Hepatitis in a Critically ill Patient During Antituberculosis Therapy

INTRODUCTION

Although hepatitis is frequently observed during antituberculosis (anti-TB) therapy, acute viral hepatitis should be ruled out first, especially in the endemic areas. In addition to common types of viral hepatitis, ie, hepatitis A, hepatitis B, and hepatitis C viruses, Epstein-Barr virus (EBV) may result in hepatitis in some cases.

CASE PRESENTATION

Herein, we reported a critically ill patient who developed cholestatic hepatitis in the intensive care unit during the anti-TB therapy, which was misdiagnosed as anti-TB agents-induced hepatitis in the beginning. Further serologic tests and liver biopsy confirmed the diagnosis of EBV hepatitis. In contrast to previously reported hepatitis by EBV, which had presented with transient liver dysfunction and self-limiting illness, hepatitis with progressive jaundice was followed by coagulopathy and encephalopathy in our case and the patient died of hepatic failure complications.

CONCLUSIONS

According to the presented case and subsequent literature review on fatal EBV hepatitis, clinicians should consider EBV infection in the differential diagnosis when hepatitis occurs in critically ill patients during the anti-TB therapy. Although hepatitis caused by EBV is mostly self-limited, some might be fetal.

Withholding parenteral nutrition during critical illness increases plasma bilirubin but lowers the incidence of biliary sludge

Cholestatic liver dysfunction (CLD) and biliary sludge often occur during critical illness and are allegedly aggravated by parenteral nutrition (PN). Delaying initiation of PN beyond day 7 in the intensive care unit (ICU) (late PN) accelerated recovery as compared with early initiation of PN (early PN). However, the impact of nutritional strategy on biliary sludge and CLD has not been fully characterized. This was a preplanned subanalysis of a large randomized controlled trial of early PN versus late PN (n = 4,640). In all patients plasma bilirubin (daily) and liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyl transpeptidase [GGT], alkaline phosphatase [ALP], twice weekly; n = 3,216) were quantified. In a random predefined subset of patients, plasma bile acids (BAs) were also quantified at baseline and on days 3, 5, and last ICU-day (n = 280). Biliary sludge was ultrasonographically evaluated on ICU-day 5 (n = 776). From day 1 after randomization until the end of the 7-day intervention window, bilirubin was higher in the late PN than in the early PN group (P < 0.001). In the late PN group, as soon as PN was started on day 8 bilirubin fell and the two groups became comparable. Maximum levels of GGT, ALP, and ALT were lower in the late PN group (P < 0.01). Glycine/taurine-conjugated primary BAs increased over time in ICU (P < 0.01), similarly for the two groups. Fewer patients in the late PN than in the early PN group developed biliary sludge on day 5 (37% versus 45%; P = 0.04).

CONCLUSION

Tolerating substantial caloric deficit by withholding PN until day 8 of critical illness increased plasma bilirubin but reduced the occurrence of biliary sludge and lowered GGT, ALP, and ALT. These results suggest that hyperbilirubinemia during critical illness does not necessarily reflect cholestasis and instead may be an adaptive response that is suppressed by early PN.

Pharmacokinetics of E5564, a Lipopolysaccharide Antagonist, in Patients with Impaired Hepatic Function

E5564 is a structural analog of the Lipid A portion of lipopolysaccharide (LPS). E5564 has been tested in several in vitro and in vivo models and has demonstrated its effectiveness against LPS. It is intended to be an antagonist of LPS to reduce the morbidity and mortality associated with sepsis syndrome. This study assessed the pharmacokinetics (PK) of E5564 in patients with impaired hepatic function. E5564 was administered via intermittent intravenous infusion every 12 hours for six times to 24 hepatic-impaired patients (12 each to Child-Pugh Classifications A and B) and 24 matching healthy volunteers. Plasma samples were analyzed by LC/MS/MS. A one-compartment model resulted in good and comparable fits for all volunteers. Regardless of liver disease state, none of the PK parameters compared (i.e., Cmax (0-12),tmax (0-12),CL,t1/2, Vss, AUC(0-12), AUC(0-last), AUC(0-infinity), C(ss,min), C(ss,max), and C(ss,av)) exhibited any difference between these two groups. This suggested that the exposure of E5564 in volunteers was independent of hepatic function. Thus, no dose adjustment is needed in patients with hepatic impairment classified as Child-Pugh A and B.

How to assess liver function?

PURPOSE OF REVIEW

The liver comprises a multitude of parenchymal and nonparenchymal cells with diverse metabolic, hemodynamic and immune functions. Available monitoring options consist of 'static' laboratory parameters, quantitative tests of liver function based on clearance, elimination or metabolite formation and scores, most notably the 'model for end-stage liver disease'. This review aims at balancing conventional markers against 'dynamic' tests in the critically ill.

RECENT FINDINGS

There is emerging evidence that conventional laboratory markers, most notably bilirubin, and the composite model for end-stage liver disease are superior to assess cirrhosis and their acute decompensation, while dynamic tests provide information in the absence of preexisting liver disease. Bilirubin and plasma disappearance rate of indocyanine green reflecting static and dynamic indicators of excretory dysfunction prognosticate unfavorable outcome, both, in the absence and presence of chronic liver disease better than other functions or indicators of injury. Although dye excretion is superior to conventional static parameters in the critically ill, it still underestimates impaired canalicular transport, an increasingly recognized facet of excretory dysfunction.

SUMMARY

Progress has been made in the last year to weigh static and dynamic tests to monitor parenchymal liver functions, whereas biomarkers to assess nonparenchymal functions remain largely obscure.

Clinical review: The liver in sepsis

During sepsis, the liver plays a key role. It is implicated in the host response, participating in the clearance of the infectious agents/products. Sepsis also induces liver damage through hemodynamic alterations or through direct or indirect assault on the hepatocytes or through both. Accordingly, liver dysfunction induced by sepsis is recognized as one of the components that contribute to the severity of the disease. Nevertheless, the incidence of liver dysfunction remains imprecise, probably because current diagnostic tools are lacking, notably those that can detect the early liver insult. In this review, we discuss the epidemiology, diagnostic tools, and impact on outcome as well as the pathophysiological aspects, including the cellular events and clinical picture leading to liver dysfunction. Finally, therapeutic considerations with regard to the weakness of the pertinent specific approach are examined.

Hypoxic hepatitis

Hypoxic hepatitis (HH), an acute liver injury also known as 'ischaemic hepatitis' or 'shock liver', is frequently observed in intensive care units. HH is heralded by a massive but transient rise in serum aminotransferase activities caused by anoxic necrosis of centrilobular liver cells. Cardiac failure, respiratory failure and toxic-septic shock are the main underlying conditions accounting for more than 90% of cases, but HH may also occur in other circumstances. Until recently, liver ischaemia, i.e. a drop in hepatic blood flow, was considered the leading, and even the sole, hemodynamic mechanism responsible for HH, and it was generally held that a shock state was required. In reality, other hemodynamic mechanisms of hypoxia, such as passive congestion of the liver, arterial hypoxaemia and dysoxia, play an important role while a shock state is observed in only 50% of cases. Accordingly, 'ischaemic hepatitis' and 'shock liver' are misnomers. Therapy of HH depends primarily on the nature of the underlying condition. The prognosis is poor, with more than half of patients dying during the hospital stay.

Early diagnostic markers of sepsis after oesophagectomy (including thromboelastography)

Background

Early diagnosis of sepsis and its differentiation from the noninfective SIRS is very important in order that treatment can be initiated in a timely and appropriate way. In this study we investigated standard haematological and biochemical parameters and thromboelastography (TEG) in patients who had undergone surgical resection of the oesophagus to find out if changes in any of these parameters could help in early differentiation between SIRS and sepsis development.

Methods

We enrolled 43 patients (aged 41–74 years) of whom 38 were evaluable. Blood samples were obtained on the morning of surgery and then at 24-hour intervals for the next 6 days. Samples were analysed for procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL- 6), aspartate transaminase (AST), alanine transaminase (ALT) , lactate, white blood count (WBC), D-dimers, antithrombin (AT), international normalised ratio (INR), activated partial thromboplastin time (APTT) and parameters of TEG.

Results

Significant differences between patients who developed sepsis during this period (9 patients) and SIRS were found in ALT on Day 1, in AST on Days 1–4, in PCT on Days 2–6; in CRP on Days 3–6; in IL-6 on Days 2–5; in leucocytes on Days 2, 3 and 6; and in D-dimers on Days 2 and 4. Significance values ranged from p < 0.0001 to p < 0.05.

Conclusions

Sequential measurements of ALT, AST, PCT and IL-6 during the early postoperative period can be used for early differentiation of sepsis and postoperative SIRS after oesophagectomy. Among the coagulation parameters measured, only D-dimer concentrations appeared to be helpful in this process. TEG does not seem to be a useful early predictor of sepsis development; however it can be used to differentiate sepsis and SIRS from Day 5 after surgery.

Recombinant human Hsp70 protects against lipoteichoic acid-induced inflammation manifestations at the cellular and organismal levels

It has been previously reported that pretreatment with exogenous heat shock protein 70 (Hsp70) is able to protect cells and animals from the deleterious effects of bacterial lipopolysaccharide (LPS) produced by Gram-negative bacteria. However, the effects of Hsp70 pretreatment on lipoteichoic acid (LTA) challenge resulted from Gram-positive bacteria infection have not been fully elucidated. In this study, we demonstrated that preconditioning with human recombinant Hsp70 ameliorates various manifestations of systematic inflammation, including reactive oxygen species, TNFα, and CD11b/CD18 adhesion receptor expression induction observed in different myeloid cells after LTA addition. Therefore, exogenous Hsp70 may provide a mechanism for controlling excessive inflammatory responses after macrophage activation. Furthermore, in a rat model of LTA-induced sepsis, we demonstrated that prophylactic administration of exogenous human Hsp70 significantly exacerbated numerous homeostatic and hemodynamic disturbances induced by LTA challenge and partially normalized the coagulation system and multiple biochemical blood parameters, including albumin and bilirubin concentrations, which were severely disturbed after LTA injections. Importantly, prophylactic intravenous injection of Hsp70 before LTA challenge significantly reduced mortality rates. Thus, exogenous mammalian Hsp70 may serve as a powerful cellular defense agent against the deleterious effects of bacterial pathogens, such as LTA and LPS. Taken together, our findings reveal novel functions of this protein and establish exogenous Hsp70 as a promising pharmacological agent for the prophylactic treatment of various types of sepsis.

Myrrh inhibits LPS-induced inflammatory response and protects from cecal ligation and puncture-induced sepsis

Myrrh has been used as an antibacterial and anti-inflammatory agent. However, effect of myrrh on peritoneal macrophages and clinically relevant models of septic shock, such as cecal ligation and puncture (CLP), is not well understood. Here, we investigated the inhibitory effect and mechanism(s) of myrrh on inflammatory responses. Myrrh inhibited LPS-induced productions of inflammatory mediators such as nitric oxide, prostaglandin E₂, and tumor necrosis factor-α but not of interleukin (IL)-1β and IL-6 in peritoneal macrophages. In addition, Myrrh inhibited LPS-induced activation of c-jun NH₂-terminal kinase (JNK) but not of extracellular signal-regulated kinase (ERK), p38, and nuclear factor-κB. Administration of Myrrh reduced the CLP-induced mortality and bacterial counts and inhibited inflammatory mediators. Furthermore, administration of Myrrh attenuated CLP-induced liver damages, which were mainly evidenced by decreased infiltration of leukocytes and aspartate aminotransferase/alanine aminotransferase level. Taken together, these results provide the evidence for the anti-inflammatory and antibacterial potential of Myrrh in sepsis.

Hepatobiliary manifestations of critically ill and postoperative patients

Liver dysfunction is common in both the critically ill and postoperative patient. Metabolic derangements secondary to sepsis, poor hepatic perfusion, total parenteral nutrition, in addition to hemodynamic and anesthetic-induced changes that occur during surgery, can cause liver damage ranging from small self-limited abnormalities in liver chemistries to acute liver failure. Early recognition, supportive care, and effective treatment of the underlying disease process are crucial steps in managing liver disease in a critically ill patient.

Molecular analysis of sepsis-induced changes in the liver: microarray study in a porcine model of acute fecal peritonitis with fluid resuscitation

Sepsis and septic shock are frequently encountered in the intensive care unit. Despite the evolution of intensive care medicine during the last decades, septic shock is still associated with high mortality and complications of sepsis such as cholestasis, liver dysfunction, and massive intravascular volume deficit. Little is known about the whole pattern of changes at the transcriptional level during the development of acute sepsis. Here we present a detailed molecular biological analysis of the events in the liver during the first day of acute bacterial infection in a clinically relevant model of porcine peritoneal sepsis. Before and 21 h after induction of sepsis by autologous fecal inoculum, liver samples were taken for microarray analysis. There were two groups of animals (7 control and 8 sepsis), two of each group where used in microarray, the remaining were used for confirmation of selected genes by real-time polymerase chain reaction. Pathway analysis revealed that in acute sepsis, gene expression was significantly changed in processes related to apoptosis, inflammation, and oxidant/redox balance. Although after 21 h these animals are expected to die within the next 3 to 4 h from massive complications, functional induction of apoptosis could not be confirmed. Computer analysis identified three key regulator genes (IL8, CCL2, and CXCL2) among the first genes to be upregulated specifically in the sepsis group, and these can directly or indirectly control the bulk of the sepsis response. Induction of inflammatory mediators by sepsis was supported by the detection of corresponding cytokines (interleukin 6 and interleukin 8) in the blood.

ICU management of acute liver failure

Survival of patients presenting with acute liver failure (ALF) has improved because of earlier disease recognition, better understanding of pathophysiology of various insults leading to ALF, and advances in supportive measures including a team approach, better ICU care, and liver transplantation. This article focuses on patient management and evaluation that takes place in the ICU for patients who have acute liver injury. An organized team approach to decision making about critical care delivered during this period of time is important for achieving a good patient outcome.

Abnormalities in aminotransferase levels during acute pyelonephritis

Liver abnormalities are common in septic patients. The study was aimed at investigating the alterations in aminotransferase levels during acute pyelonephritis in adults. Serum aminotransferases (AST and ALT) were determined in 421 patients (aged 16-90 years, 79.8% females) admitted to the hospital because of acute pyelonephritis. Abnormally high aminotransferase (sAST or sALT) levels were present in 21.4% (95% CI 17.6-25.9%) of patients without pre-existing liver disease (n=401). Aminotransferase abnormality was moderate in the majority of cases. After adjusting for confounders, aminotransferase abnormality was associated with age and with signs of sepsis (particularly, high body temperature and low blood pressure). Aminotransferase levels tended to normalize during convalescence. In conclusion, the management of patients with pyelonephritis should take into account that moderate and self-limited abnormalities in aminotransferase levels are frequent during the acute phase of the disease.

Age-related decrease in proteasome expression contributes to defective nuclear factor-kappaB activation during hepatic ischemia/reperfusion

Hepatic ischemia/reperfusion (I/R) leads to liver injury and dysfunction through the initiation of a biphasic inflammatory response that is regulated by the transcription factor nuclear factor kappaB (NF-kappaB). We have previously shown that there is an age-dependent difference in the injury response to hepatic I/R in mice that correlates with divergent activation of NF-kappaB such that young mice have greater NF-kappaB activation, but less injury than old mice. In this study, we investigated the mechanism by which age alters the activation of NF-kappaB in the liver during I/R. Young (4-5 weeks) and old (12-14 months) mice underwent partial hepatic I/R. Livers were obtained for RNA microarray analysis and protein expression assays. Using microarray analysis, we identified age-dependent differences in the expression of genes related to protein ubiquitinylation and the proteasome. In old mice, genes that are involved in the ubiquitin-proteasome pathway were significantly down-regulated during I/R. Consistent with these findings, expression of a critical proteasome subunit, non-adenosine triphosphatase 4 (PSMD4), was reduced in old mice. Expression of the NF-kappaB inhibitory protein, IkappaB alpha, was increased in old mice and was greatly phosphorylated and ubiquitinylated. The data provide strong evidence that the age-related defect in hepatic NF-kappaB signaling during I/R is a result of decreased expression of PSMD4, a proteasome subunit responsible for recognition and recruitment of ubiquitinylated substrates to the proteasome. It appears that decreased PSMD4 expression prevents recruitment of phosphorylated and ubiquitinylated IkappaB alpha to the proteasome, resulting in a defect in NF-kappaB activation.

Thoracic but not lumbar epidural anaesthesia increases liver blood flow after major abdominal surgery

BACKGROUND AND OBJECTIVE

Epidural blockade in major abdominal surgery bears the potential to increase gastrointestinal perfusion and thus to improve patient outcome. The aim of this study was to assess the differential influence of thoracic and lumbar epidural anaesthesia and analgesia (EAA) on blood lactate levels and central venous oxygen saturation (ScvO2) as parameters of global oxygen supply/demand ratio, as well as on the plasma disappearance rate of indocyanine green (PDR(ICG)), a noninvasive method to evaluate liver perfusion.

METHODS

We enrolled 17 patients receiving thoracic and 17 patients receiving lumbar EAA in addition to general anaesthesia for major abdominal surgery. Lactate, ScvO2 and PDR(ICG) were measured postoperatively on the ICU. Subsequently, epidural application of local anaesthetics was started with a bolus of bupivacaine 0.25% (thoracic 10 ml, lumbar 12 ml) followed by continuous infusion of bupivacaine (thoracic 8 ml h(-1) 0.175%, lumbar 10 ml h(-1) 0.125%) and fentanyl (2 microg ml(-1)). Central venous pressure was maintained by titrated volume replacement. Lactate, ScvO2 and PDR(ICG) were measured again after 2 h.

RESULTS

In both the groups, the mean arterial pressure and heart rate as well as lactate levels and ScvO2 did not change significantly. Although there was a slight but not significant decrease of PDR(ICG) in patients with lumbar EAA (from 25.9 +/- 7.68 to 23.2 +/- 5.90; NS), thoracic EAA resulted in a significant increase of PDR(ICG) (from 21.3 +/- 5.13 to 24.0 +/- 6.66; P < 0.05) for the group mean, but with substantial variability in individual patients in the lumbar EAA group.

CONCLUSION

Liver perfusion was increased with thoracic but not lumbar EAA after major abdominal surgery in most patients. PDR(ICG) allows assessment of individual changes of liver blood flow due to therapeutic intervention, for example, EAA.

Peroxiredoxin-6 protects against mitochondrial dysfunction and liver injury during ischemia-reperfusion in mice

Hepatic ischemia-reperfusion (I/R) injury is an important complication of liver surgery and transplantation. Mitochondrial function is central to this injury. To examine alterations in mitochondrial function during I/R, we assessed the mitochondrial proteome in C57Bl/6 mice. Proteomic analysis of liver mitochondria revealed 234 proteins with significantly altered expression after I/R. From these, 13 proteins with the greatest expression differences were identified. One of these proteins, peroxiredoxin-6 (Prdx6), has never before been described in mitochondria. In hepatocytes from sham-operated mice, Prdx6 expression was found exclusively in the cytoplasm. After ischemia or I/R, Prdx6 expression disappeared from the cytoplasm and appeared in the mitochondria, suggesting mitochondrial trafficking. To explore the functional role of Prdx6 in hepatic I/R injury, wild-type and Prdx6-knockout mice were subjected to I/R injury. Prdx6-knockout mice had significantly more hepatocellular injury compared with wild-type mice. Interestingly, the increased injury in Prdx6-knockout mice occurred despite reduced inflammation and was associated with increased mitochondrial generation of H(2)O(2) and dysfunction. The mitochondrial dysfunction appeared to be related to complex I of the electron transport chain. These data suggest that hepatocyte Prdx6 traffics to the mitochondria during I/R to limit mitochondrial dysfunction as a protective mechanism against hepatocellular injury.

Adiponectin deficiency promotes the production of inflammatory mediators while severely exacerbating hepatic injury in mice with polymicrobial sepsis

BACKGROUND

Adiponectin (APN), which is an adipose tissue-derived hormone, is known as an anti-inflammatory cytokine. The effects of APN on the production of inflammatory mediators and hepatic injury during polymicrobial sepsis were evaluated using APN-knockout (KO) mice that had undergone a cecal ligation and puncture (CLP) and rosiglitazone, a selective peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, which increases the plasma APN concentration.

MATERIALS AND METHODS

Wild type (WT) and APN-KO mice were underwent CLP. The plasma and hepatic levels of inflammatory mediators, including tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1), were measured before, at 24, and 48 h after CLP. A histological analysis of the liver and the plasma alanine aminotransferase (ALT) levels were examined to evaluate hepatic injury. The plasma levels of inflammatory mediators after CLP with pretreatment of rosiglitazone were compared with those without rosiglitazone.

RESULTS

APN deficiency resulted in significant increases in the plasma levels of TNF-alpha, IL-6, and MCP-1 at 24 h after CLP. Hepatic MCP-1 and plasma AST levels in APN-KO mice were significantly higher than those in WT mice at 48 h after CLP. A steatosis change and MCP-1 expressions in hepatocytes were induced in APN-KO mice during sepsis. The administration of rosiglitazone significantly lowered the plasma levels of inflammatory mediators, including TNF-alpha, IL-6, and MCP-1, in WT mice but not in APN-KO mice during sepsis.

CONCLUSION

These results suggest that an APN deficiency induces an excessive systemic inflammatory status and exacerbates hepatic injury during polymicrobial sepsis.

Plasma antioxidant status in septic critically ill patients: a decrease over time

Severe septic states in humans are responsible for intense intravascular oxidative stress, which induces numerous adaptive mechanisms. We determined time sequence changes in total plasma antioxidant capacity (TAC) and major plasma antioxidant concentrations, which have not been fully explained in septic conditions. A cohort of 56 consecutive septic patients (septic shock n = 37, severe sepsis n = 19) and six healthy volunteers. We compared TAC and antioxidant levels in patients with one of two degrees of septic states, at the onset of illness, to those of healthy volunteers. Thereafter, over a 10-day follow-up, we observed daily the time sequence changes of the two septic populations in terms of TAC and antioxidants. At the onset, there was no difference between the three groups in terms of TAC values (healthy subjects 2.18 +/- 0.04; severe sepsis 2.03 +/- 0.07; septic shock 2.09 +/- 0.09), then an equivalent time decline was observed in the two septic populations whatever the severity. TAC was statistically linked to uric acid, proteins in particular albumin and bilirubin (multivariate analysis), but no correlation was found with any vitamin (A, C and E). A sharp and persistent decrease in vitamin C concentrations was underlined. TAC, unaffected at first, deteriorated over time whatever the severity of the infection in these critically ill patients. TAC, unable to distinguish severe sepsis and septic shock, is unlikely to be a particularly useful outcome measure.

Protein C: a potential biomarker in severe sepsis and a possible tool for monitoring treatment with drotrecogin alfa (activated)

Introduction

Drotrecogin alfa (activated; DrotAA) treatment, a 96-hour infusion, reduces 28-day mortality in severe sepsis to approximately 25%. The question remains whether a longer infusion or higher dose could increase rate of survival. The goal of this study was to identify a dependable, sensitive measure with which to monitor disease progression and response in patients during DrotAA treatment.

Methods

Data on severe sepsis patients included in PROWESS (placebo-controlled, double-blind, randomized study of 850 DrotAA and 840 placebo individuals) and ENHANCE (single-arm, open-label study of 2,375 DrotAA patients) studies were analyzed. In these studies, DrotAA (24 μg/kg per hour) or placebo was infused for 96 hours and patients were followed for 28 days. Data on six laboratory measures and five organ dysfunctions were systematically analyzed to identify a potential surrogate end-point for monitoring DrotAA therapy and predicting 28-day mortality at the end of therapy. To allow comparison across variables, sensitivity and specificity analyses identified cut-off values for preferred outcome, and relative risks for being above or below cut-offs were calculated, as was the 'proportion of treatment effect explained' (PTEE) to identify biomarkers that contribute to benefit from DrotAA.

Results

Protein C was the only variable that correlated with outcome across all analyses. Using placebo data, a baseline protein C under 40% was established as a useful predictor of outcome (odds ratio 2.12). Similar odds ratios were associated with cut-off values of other biomarkers, but the treatment benefit associated with DrotAA was significantly greater below the cut-off than above the cut-off only for protein C (relative risk for 28-day mortality 0.66 versus 0.88; P = 0.04). Protein C was the only end-of-infusion biomarker that potentially explained at least 50% of the benefit from DrotAA (PTEE 57.2%). The PTEE was 41% for cardiovascular Sequential Organ Failure Assessment score and for d-dimer. At the end of infusion (day 4), protein C categories (≤40%, 41% to 80%, and > 80%) remained significantly related to mortality, regardless of treatment assignment.

Conclusion

Based on systematic analyses of 11 variables measured in severe sepsis clinical trials, protein C was the only variable consistently correlated with both DrotAA treatment effect and survival. Further study is needed to determine whether longer infusions or higher doses of DrotAA would achieve the goal of normalizing protein C in more patients with severe sepsis.

Sepsis and cholestasis

Cholestasis is a common complication of bacterial infections and sepsis. This article gives a comprehensive overview of the underlying molecular mechanisms of sepsis-associated cholestasis and jaundice, their clinical presentation, and diagnostic and therapeutic management.

Role of nitric oxide in the expression of hepatic vascular stress genes in response to sepsis

This study examined the role of nitric oxide (NO) on the expression of the hepatic vasoregulatory gene during polymicrobial sepsis. Aminoguanidine (AG, 100 mg/kg) or Nomega-nitro-L-arginine methyl ester (L-NAME, 100 mg/kg) was injected intraperitoneally at 0, 3, 6, 10, and 20 h after a cecal ligation and puncture (CLP). The heart rate increased 24 h after the CLP, and this increase was attenuated by L-NAME and further attenuated by AG. The mean arterial pressure in the CLP animals did not change significantly 24 h after the onset of sepsis but was increased after the L-NAME injection. Sepsis increased the serum aminotransferase levels, which were attenuated by AG but augmented by L-NAME. CLP increased the mRNA level of the ET-1 and ETB receptors in the liver. This increase was prevented by AG but augmented by L-NAME. The level of iNOS and HO-1 mRNA expression were increased by CLP, which was prevented by both AG and L-NAME. The level of TNF-alpha and COX-2 mRNA expression increased after CLP, and was attenuated by AG. These results show that iNOS and eNOS are regulated differently in sepsis. While eNOS appears to have a protective role in liver microcirculation, the strong upregulation of iNOS might contribute to a microvascular dysfunction and hepatic injury.

Liver dysfunction in patients with acute pulmonary embolism

AIM

Although liver injury due to cardiac, chronic respiratory and circulatory failure has been reported, this has yet to be studied in patients with pulmonary embolism (PE). We investigated liver injury in patients with acute PE.

METHODS

We retrospectively reviewed 107 acute PE patients over a two-year period. Patients were categorized as having: (1) severe (P(a)O(2) < 45 mmHg), moderate (45 mmHg </= P(a)O(2)</= 60 mmHg) or mild hypoxemia (60 mmHg < P(a)O(2) < 80 mmHg) groups; (2) massive and non-massive PE; (3) absence or presence of pre-existing cardiopulmonary disease; and (4) absence or presence of right ventricle dysfunction. Serum levels of liver enzymes were compared between groups.

RESULTS

Transaminase levels were higher in severe hypoxemia patients compared mild hypoxemia patients (p=0.045 and p=0.036). Albumin and bilirubin levels were lower and higher, respectively, in patients with severe and moderate hypoxemia compared to mild hypoxemia patients (p < 0.05 and p < 0.01). There was a negative correlation between hepatic markers and P(a)O(2) and %S(a)O(2): r=-0.212, p=0.032 between AST and %S(a)O(2); r=-0.243, p=0.013 and r=-0.241, p=0.014 between ALT and P(a)O(2) and %S(a)O(2); and r=-0.224, p=0.024 and r= -0.283, p=0.004 between direct bilirubin and P(a)O(2) and %S(a)O(2). AST and ALT levels were higher in massive PE than non-massive PE patients (p=0.0001). Albumin levels were lower in patients with right ventricle dysfunction than in those without (p=0.02). One (0.9%) had a clinical picture of hypoxic hepatitis.

CONCLUSION

Abnormal LFTs showed a mixed pattern in patients with acute PE.

Jaundice in the intensive care unit

Hyperbilirubinemia, or jaundice, is common in the ICU, with incidence up to 40% among critically ill patients. Unfortunately, it is poorly understood in the critically ill, and too often presents a diagnostic dilemma to the ICU physician. Causes of jaundice in the ICU are multiple; the etiology in any given patient, multifactorial. Acute jaundice can be a harbinger or marker of sepsis, multisystem organ failure (MSOF), or a reflection of transient hypotension (shock liver), right-sided heart failure, the metabolic breakdown of red blood cells, or pharmacologic toxicity. Acute ICU jaundice is best divided into obstructive and nonobstructive. This stratification directs subsequent management and therapeutic decisions.

Unusual Manifestation of Severe Conjugated Hyperbilirubinemia in an Infant with Streptococcus pneumoniae-associated Hemolytic Uremic Syndrome

Streptococcus pneumoniae is an uncommon etiologic organism in children with hemolytic uremic syndrome (HUS). Historically, severe S. pneumoniae-associated HUS usually has a poor clinical outcome. The clinical manifestations of marked jaundice and hepatic dysfunction in this form of HUS are extremely rare. We report a 10-month-old female infant with S. pneumoniae-associated HUS who had the unusual manifestation of severely elevated conjugated bilirubin and hepatic transaminases. Screening for viral hepatitis was negative, and evidence of biliary obstruction and hepatotoxic drug exposure was also absent. The patient was treated with antihypertensive agents for 2.5 months and required peritoneal dialysis for a period of 26 days. Hepatic function returned to normal on the 8th day of hospitalization. Renal function was mildly impaired at 1-year follow-up. Our report suggests that severe conjugated hyperbilirubinemia is a rare manifestation of S. pneumoniae-associated HUS in children. It is important for pediatricians that pneumococcal infection with severe hematologic and renal disorders should be investigated for evidence of S. pneumoniae-associated HUS.

Ascites in infants with severe sepsis - treatment with peritoneal drainage

BACKGROUND

Ascites in neonates and infants is usually caused by cardiac failure and urinary or biliary tract obstruction. The objective of this study was to characterize our experience with ascites as a complication of sepsis.

METHODS

We retrospectively collected and analyzed data of patients treated in the intensive care unit (ICU) of the university-based children's hospital, in whom ascites developed during nosocomial sepsis. Ten infants admitted to the ICU in the first 2 days of life developed sepsis on the mean 31.5 (+/-21.9) postnatal day. Gram-negative bacteria were the causative organism in nine cases, and Staphylococcus hemolyticus in one. Because of sepsis, reintubation and mechanical ventilation were necessary. All patients received broad spectrum antibiotics (including meropenem and ciprofloxacin), blood transfusions, catecholamines and intravenous immunoglobulin preparations. Ascites was observed on the median 13.5 day of sepsis (range 3-36), and severely compromised gas exchange. Continuous peritoneal drainage was applied by means of an intravascular catheter placed in the right lower abdominal quadrant.

RESULTS

The mean drained fluid volume was 44.7 (+/-20.4) ml.kg(-1).day(-1), drainage was continued for a median of 5.5 (range 1-56) day, and enabled significant reduction of ventilator settings 24 h after its implementation. No severe complications related to drainage occurred; six of 10 babies survived.

CONCLUSIONS

Ascites can develop in infants with sepsis and cause respiratory compromise. Continuous drainage of ascitic fluid by means of an intravenous catheter is relatively safe and can improve gas exchange.

Pathogenesis of liver involvement during dengue viral infections

The dengue virus can infect many cell types and cause diverse clinical and pathological effects. We describe clinical and experimental observations that suggest that liver involvement occurs during dengue infections, and we outline the possible role played by host immune responses in this process.

Jaundice in critical illness: promoting factors of a concealed reality

OBJECTIVE

In critical illness, liver dysfunction (LD) is associated with a poor outcome independently of other organ dysfunctions. Since strategies to support liver function are not available, a timely and accurate identification of factors promoting LD may lead to prevention or attenuation of its consequences. The aim of this study was to assess risk factors for LD in critically ill patients.

DESIGN

Prospective, observational study.

SETTING

A multidisciplinary intensive care unit (ICU) of a university hospital.

PATIENTS

All patients consecutively admitted over a 6-month period.

INTERVENTION

None.

MEASUREMENTS AND RESULTS

LD was defined as serum bilirubin levels >or=2 mg/dl and lasting for at least 48 h. Out of 283 patients, 141 matched inclusion criteria. Forty-four patients (31.2%) showed LD (LD group), while 97 (68.8%) were included in control group (C group). A binomial analysis showed that LD occurrence was associated with moderate (odds ratio [OR] 3.11; p=0.04) and severe shock (OR 3.46; p= 0.05), sepsis (OR 3.03; p=0.04), PEEP ventilation (OR 4.25; p=0.006), major surgery (OR 4.03; p=0.03), and gram-negative infections (OR 3.94; p=0.002). In stepwise multivariate analysis, the single independent predictive factors of LD resulted in severe shock (p=0.002), sepsis (p=0.03), PEEP ventilation (p=0.04), and major surgery (p=0.05).

CONCLUSIONS

In critically ill patients jaundice is common, and severe shock states, sepsis, mechanical ventilation with PEEP and major surgery are critical risk factors for its onset. Since there is no specific treatment, prompt resuscitation, treatment of sepsis and meticulous supportive care will likely reduce its incidence and severity.

Relationship between hypoxic hepatitis and cor pulmonale in patients treated in the respiratory ICU

To determine independent risk factors associated with the pathogenesis hypoxic hepatitis (HH) in hypoxemic patients. The prospective study, multivariate analysis, between January 1999 and March 2003 was conducted at University hospital, intensive care unit, Department of Chest Diseases. A total of 445 consecutive patients were included in the study. Patients who were not hypoxemic (PaO(2) > 80 mmHg) were excluded from analysis. The total number of those found eligible for the study was 297. Patients with a >20-fold increase in liver enzyme levels were diagnosed as HH (study group). The other patients were defined as control group. There were no interventions. Mean age was 62, and 191 were males. Twenty-two patients were diagnosed as HH (study group; 7.41%). Cor pulmonale (CP) was 77.3% in the study group and 36.7% in the control group. The need for mechanical ventilation and hospital mortality were 63.6 and 54.5% in the study group and 32 and 28.7% in the control group, respectively. On multivariate analysis, the presence of CP (p = 0.007; OR: 4.418; CI: 1.492-13.083), high-serum BUN level (>37 mg/dl; p = 0.0001; OR: 1.029; CI: 1.015-1.044) and low PaO(2) level (<46 mmHg; p = 0.008; OR: 0.945; CI: 0.906-0.985) were found to be significantly different between the two groups. Patients with severe hypoxemia, CP and higher BUN level have higher risk levels for HH, the most important risk factor being CP.

[Acute liver failure. Current aspects of diagnosis and therapy]

Disturbances of some partial liver functions, such as synthesis, excretion, or biotransformation of xenobiotics, are important for prognosis and ultimate survival in patients presenting with multiple organ dysfunction on the intesive care unit (ICU). The incidence of liver dysfunction is underestimated when traditional "static" measures such as serum-transaminases or bilirubin as opposed to "dynamic" tests, such as clearance tests, are used to diagnose liver dysfunction. Similar to the central role of the failing liver in MODS, extrahepatic complications, such as hepatorenal syndrome and brain edema develop in acute or fulminant hepatic failure and determine the prognosis of the patient. This is reflected in the required presence of hepatic encephalopathy in addition to hyperbilirubinemia and coagulopathy for the diagnosis of acute liver failure. In addition to these clinical signs, dynamic tests, such as indocyanine green clearance, which is available at the bed-side, are useful for the monitoring of perfusion and global liver function. In addition to specific and causal therapeutic interventions, e.g. N-acetylcysteine for paracetamol poisoning or termination of pregnancy for the HELLP-syndrome, new therapeutic measures, e.g. terlipressin/albumin or albumin dialysis are likely to improve the poor prognosis of acute-on-chronic liver failure. Nevertheless, liver transplantation remains the treatment of choice for fulminant hepatic failure when the expected survival is <20%.

Hypoxic hepatitis: clinical and hemodynamic study in 142 consecutive cases

The centrilobular liver cell necrosis observed in hypoxic hepatitis is generally attributed to failure of hepatic blood perfusion. Accordingly, this injury of the liver is commonly recognized under the terms "shock liver" or "ischemic hepatitis." During a 10-year period, 142 episodes of hypoxic hepatitis were consecutively identified in the intensive care unit of a general hospital, and the clinical, biological, and hemodynamic parameters were prospectively collected on individual files. We conducted the current study to assess retrospectively the role of the hemodynamic mechanisms of tissue hypoxia: ischemia, passive venous congestion, and hypoxemia. Among the 142 episodes of hypoxic hepatitis, 138 were separated in 4 main groups based on clinical features: decompensated congestive heart failure (80 cases), acute cardiac failure (20 cases), exacerbated chronic respiratory failure (19 cases), and toxic/septic shock (19 cases). An elementary hemodynamic evaluation, including blood pressure, central venous pressure, and arterial blood gas analysis, was carried out in every episode and a more complete hemodynamic assessment through pulmonary artery catheterization was performed in 61 episodes. The hemodynamic mechanisms responsible for hypoxic hepatitis were different in the 4 groups. In congestive heart failure and acute heart failure, the hypoxia of the liver resulted from decreased hepatic blood flow (ischemia) due to left-sided heart failure and from venous congestion secondary to right-sided heart failure. In chronic respiratory failure, liver hypoxia was mainly due to profound hypoxemia. In toxic/septic shock, oxygen delivery to the liver was not decreased but oxygen needs were increased, while the liver was unable to use oxygen properly. In all conditions underlying hypoxic hepatitis, except toxic/septic shock, a shock state was observed in only about 50% of the cases. Therefore, the expressions "shock liver" or "ischemic hepatitis" are misleading and should be replaced by the more general term "hypoxic hepatitis."