Post-operative hypoalbuminaemia and procalcitonin elevation for prediction of outcome in cardiopulmonary bypass surgery

Alterations in novel inflammatory biomarkers during perioperative cardiovascular surgeries involving cardiopulmonary bypass: a retrospective propensity score matching study

Background

Cardiopulmonary bypass (CPB) triggers a strong inflammatory response in cardiovascular surgery patients during the perioperative period. This article mainly focuses on the perioperative application of novel inflammatory biomarkers in cardiovascular surgeries involving CPB.

Methods

Patients were divided into a CPB group and a non-CPB group according to whether they underwent CPB during cardiovascular surgery. Novel inflammatory biomarkers and clinical results were recorded. The neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), platelet × neutrophil/lymphocyte ratio (SII), and monocyte × platelet × neutrophil/lymphocyte ratio (PIV) were calculated. The primary outcomes were perioperative prognosis between the CPB and non-CPB groups. The secondary outcomes included perioperative alterations of novel inflammatory biomarkers in the CPB group and predictive values of novel inflammatory biomarkers for postoperative infection and acute kidney injury.

Results

A total of 332 patients were initially included in the study. Before propensity score matching (PSM), there were 96 patients in the CPB group and 236 patients in the non-CPB group. After PSM, both groups included 58 patients each. Compared with the non-CPB group, the CPB group had a higher proportion of intraoperative transfusion of blood products (63.79% vs. 6.90%, P < 0.001), specifically for red blood cells (58.62% vs. 3.45%, P < 0.001) and plasma (41.38% vs. 1.72, P < 0.001), exhibited a higher drainage fluid volume within 24 h [380 (200-550) ml vs. 200 (24-330) ml, P = 0.002], and required longer durations of mechanical ventilation [14.3 (6.6-21.3) h vs. 5.75 (4.08-10.1) h, P < 0.001] and ICU stay [48.78 (44.92-89.38) h vs. 27.16 (21.67-46.25) h, P < 0.001]. After surgery, NLR [14.00 (9.93-23.08) vs. 11.55 (7.38-17.38), P = 0.043] was higher in the CPB group, while the PIV, PLR, and SII in the CPB group were lower than those in the non-CPB group on the first day after surgery.

Conclusions

Cardiovascular surgeries involving CPB exhibit a poorer prognosis compared to non-CPB procedures. Novel inflammatory biomarkers, including PLR, PIV, and SII, may offer valuable insights into the degree of postoperative inflammation, with NLR emerging as a potentially reliable prognostic indicator.

The Efficacy of Diabetic Foot Treatment in a "TOSF" Pattern: A Five-Year Retrospective Study

Aim

To evaluate the advantages and problems in the diagnosis and treatment of diabetic foot (DF) patients by analyzing the results of a 5-year follow-up of the organ system based (TOSF) treatment model.

Methods

A retrospective study was conducted in 229 patients with diabetic foot. Chi-square test and rank-sum test were used to analyze the effects of patients' general condition, behavioral and nutritional status, degree of infection (inflammatory markers), comorbidity, diabetic foot grade/classification, and revascularization on readmission rate, amputation rate, all-cause mortality, incidence of other complications, and wound healing time. Logistic regression was used to analyze the risk factors affecting the prognosis of diabetic foot. Kaplan-Meier survival curve was used to analyze the differences in amputation rate and mortality rate at each time point.

Results

This study showed that nutritional status, degree of infection, and revascularization influenced readmission rates. General condition, behavior and nutritional status, degree of infection, Wagner grade and revascularization affect the amputation rate. General conditions, behavioral and nutritional status, degree of infection, comorbidities, classification and revascularization affect the mortality of patients. Age and white blood cell(WBC) count affected the incidence of other complications. Influence of infection degree and Wagner grade and revascularization in patients with wound healing time. Revascularization was an independent protective factor for readmission, amputation, and mortality.Elevated serum inflammatory markers are an independent risk factor for amputation. Hypoproteinemia is an independent risk factor for mortality.

Conclusion

In the "TOSF" diagnosis and treatment pattern, diabetic foot patients have a good prognosis. Special attention should be paid to the screening and revascularization of lower extremity vascular disease in patients with diabetic foot.

Procalcitonin/Albumin Ratio Predicts the Outcome After Severe Traumatic Brain Injury: A Propensity Score-Matched Analysis

BACKGROUND

The procalcitonin/albumin ratio (PAR), a novel inflammation-based index, has been reported to predict the prognosis following cardiopulmonary bypass surgery and bacterial infection. However, whether PAR can predict the outcome of patients with severe traumatic brain injury (STBI) has not been fully elucidated. This study aimed to investigate the relationship between serum PAR levels and prognosis at 6 months after STBI.

METHODS

We retrospectively enrolled 129 patients diagnosed with STBI and collected relevant clinical and laboratory data. Logistic regression analysis was used to estimate the association of PAR with the prognosis of STBI. The receiver operating characteristics curve was performed to examine the predictive use of PAR for prognosis. Propensity score matching (PSM) analysis was also performed to improve the reliability of the results. The primary outcome measures were expressed as a score on the modified Rankin Scale at 6 months.

RESULTS

The unfavorable prognosis group had advanced age, lower Glasgow Coma Scale score, higher rate of cerebral hernia and intracranial infection, higher neutrophil/lymphocyte ratio (NLR) and C-reactive protein/albumin ratio (CAR), elevated PAR, and higher rate of pneumonia. Multivariate analysis showed that PAR (before PSM: odds ratio 3.473, 95% confidence interval 2.983-4.043, P < 0.001; after PSM: odds ratio 5.358, 95% confidence interval 3.689-6.491, P < 0.001) was independently associated with unfavorable outcome. The area under the curve of the PAR for predicting an unfavorable outcome was higher than that of the CAR and NLR.

CONCLUSIONS

The PAR might be a novel independent risk factor of the outcome after STBI. Moreover, PAR was a better biomarker in predicting the outcome of patients with STBI than CAR and NLR.

Predictive value of perioperative procalcitonin, C reactive protein and high-sensitivity C reactive protein for the risk of postoperative complications after non-cardiac surgery in elderly patients: a nested case-control study

OBJECTIVE

Little is known about the correlation between perioperative concentrations of inflammatory biomarkers and postoperative complications. This study explored whether the plasma concentrations and perioperative changes of procalcitonin (PCT), C reactive protein (CRP) and high-sensitivity CRP (hsCRP) could predict the risk of postoperative morbidity in elderly patients undergoing elective non-cardiac surgery.

DESIGN

A nested case-control study.

SETTING

A tertiary hospital in China.

PARTICIPANTS

A total of 498 patients aged ≥65 years from a prospective cohort who underwent elective non-cardiac surgery between June 2020 and April 2021.

PRIMARY OUTCOME MEASURES

The primary outcomes were the efficacy of plasma concentrations of PCT, CRP and hsCRP in predicting the risk of Clavien-Dindo Classification (CDC) ≥grade 3 and major complications. The major complications included mortality, an intensive care unit stay length >24 hour, cardiovascular events, acute kidney injury, postoperative cognitive dysfunction and infections.

RESULTS

For major complications, the area under the curve (AUC) (95% CI) of PCT-24 hours, PCT change and PCT change rate were 0.750 (0.698 to 0.803), 0.740 (0.686 to 0.795) and 0.711 (0.651 to 0.771), respectively. The AUC (95% CI) of CRP-24 hours, CRP change, CRP change rate and hsCRP baseline were 0.835 (0.789 to 0.881), 0.818 (0.770 to 0.867), 0.691 (0.625 to 0.756) and 0.616 (0.554 to 0.678), respectively. For complications ≥CDC grade 3, the AUC (95% CI) of PCT-24 hours, PCT change and PCT change rate were 0.662 (0.543 to 0.780), 0.643 (0.514 to 0.772) and 0.627 (0.494 to 0.761), respectively. The AUC (95% CI) of CRP-24 hours and hsCRP baseline were 0.649 (0.527 to 0.771) and 0.639 (0.530 to 0.748), respectively.

CONCLUSIONS

PCT-24 hours, CRP-24 hours, the change of perioperative PCT and CRP were valuable predictors of major complications occurring within 30 days after non-cardiac surgery in the elderly.

TRIAL REGISTRATION NUMBER

China Clinical Trial Registry: ChiCTR1900026223.

The Associations Between Preoperative Anthropometry and Postoperative Outcomes in Infants Undergoing Congenital Heart Surgery

Aim:

We explored the association between preoperative anthropometry and biochemistry, and postoperative outcomes in infants with CHD after cardiac surgery, as infants with congenital heart disease (CHD) often have feeding difficulties and malnutrition.

Methodology

This was a retrospective review of infants (≤ 1-year-old) who underwent congenital heart surgery. Preoperative anthropometryin terms of preoperative weight-for-age z-score (WAZ), length-for-age z-score (LAZ), as well as preoperative serum albumin and hemoglobin concentrations, were evaluated against 6-month mortality, and morbidity outcomes including postoperative complications, vasoactive inotrope score, duration of mechanical ventilation, length of stay in the pediatric intensive care unit and in hospital, using the logistic regression or median regression models accounting for infant-level clustering.

Results

One hundred and ninety-nine operations were performed in 167 infants. Mean gestational age at birth was 38.0 (SD 2.2) weeks (range 26 to 41 weeks). Thirty (18.0%) infants were born preterm (<37 weeks). The commonest acyanotic and cyanotic lesions were ventricular septal defect (26.3%, 44/167), and tetralogy of Fallot (13.8%, 23/167), respectively. Mean age at cardiac surgery was 94 (SD 95) days. Feeding difficulties, including increased work of breathing during feeding, diaphoresis, choking or coughing during feeding, and inability to complete feeds, was present in 54.3% (108/199) of infants prior to surgery, of which 21.6% (43/199) required tube feeding. The mean preoperative WAZ was−1.31 (SD 1.79). Logistic regression models showed that low preoperative WAZ was associated with increased risk of postoperative complications (odds ratio 1.82; p = 0.02), and 6-month mortality (odds ratio 2.38; p = 0.008) following CHD surgery. There was no meaningful association between the other preoperative variables and other outcomes.

Conclusion

More than 50% of infants with CHD undergoing cardiac surgery within the first year of life have feeding difficulties, of which 22% require to be tube-fed. Low preoperative WAZ is associated with increased postoperative complications and 6-month mortality.

Do biomarkers have predictive value in the treatment modality of the patients diagnosed with bowel obstruction?

OBJECTIVES

This study aimed to investigate the ability of the biomarkers to predict the surgery treatment and mortality in patients above 18 years of age who were hospitalized with the diagnosis of bowel obstruction from the emergency department.

METHODS

This is a 2-year retrospective study. The patients' demographic data, laboratory parameters on admission to emergency department, treatment modalities, and the length of hospital stay were recorded. Patients were divided into two groups: conservative and surgical treatment. Statistical analysis was performed to investigate the value of biomarkers in predicting mortality and the need for surgery. Data were analyzed using IBM SPSS version 22.

RESULTS

A total of 179 patients were included in this study. Of these, 105 (58.7%) patients were treated conservative and 74 (41.3%) were treated operatively. The elevated procalcitonin (PCT) level, C-reactive protein, blood urea nitrogen-to-albumin ratio, and lactate-to-albumin ratio were significantly correlated with surgical treatment, length of hospital stay, and mortality. procalcitonin threshold value of 0.13 ng/mL was able to predict the need for surgical treatment, with a sensitivity of 79% and a specificity of 70.3%. Procalcitonin threshold value of 0.65 ng/mL was able to predict the mortality rate of the patients, with a sensitivity of 92.9% and a specificity of 78.1%.

CONCLUSIONS

Biomarkers, especially procalcitonin, may be useful in bowel obstruction treatment management and may predict mortality.

Prognostic Value of Procalcitonin for Morbidity and Mortality in Patients after Cardiac Surgery

Background

The increased serum procalcitonin (PCT) level in cardiac patients is known as a sign of postoperative complications.

Objective

Considering the importance of predicting the incidence of both complications and mortality caused by coronary artery bypass graft (CABG) surgery, this study was conducted to determine the serum PCT level and its relationship with one-year morbidity and mortality among CABG patients.

Methods

This descriptive-analytical study was performed on 100 patients who underwent CABG surgery in Vali-e-Asr Hospital of Birjand, Iran. They were selected by a census sampling method from March 2014 to March 2015. The Elecsys BRAHMS PCT kit (Roche Company) was then used to measure the patients' serum PCT level. The required data were collected using the patients' medical records and telephone interviews with the patient or his/her relatives by passing one year from their discharge. The outcomes of this study comprised of mortality and morbidity causes (e.g., dysrhythmia, infection, and stroke). The data were then analyzed in SPSS version 16 by Mann–Whitney, chi-squared, and Fisher exact tests.

Results

The postoperative serum PCT level is significantly correlated with sternum wound infection (p=0.001), packed cells (PC) transfusion (p=0.003), and death (p=0.003). In addition, a significant relationship was found between dyslipidemia and hypertension and early mortality rate in patients with high levels of PCT. Of note, risk-adjusted death did not differ significantly between the serum PCT levels after one year (RR, 0.068; 95% CI 0.008–0.566).

Conclusion

Higher PCT serum levels in CABG patients are associated with the increased early mortality rate, sternum wound infection, and PC transfusion. Additionally, the other factors associated with mortality in the patients under study included dyslipidemia and hypertension.

Identification and Validation of Potential miRNAs, as Biomarkers for Sepsis and Associated Lung Injury: A Network-Based Approach

Sepsis is a dysregulated immune response disease affecting millions worldwide. Delayed diagnosis, poor prognosis, and disease heterogeneity make its treatment ineffective. miRNAs are imposingly involved in personalized medicine such as therapeutics, due to their high sensitivity and accuracy. Our study aimed to reveal the biomarkers that may be involved in the dysregulated immune response in sepsis and lung injury using a computational approach and in vivo validation studies. A sepsis miRNA Gene Expression Omnibus (GEO) dataset based on the former analysis of blood samples was used to identify differentially expressed miRNAs (DEMs) and associated hub genes. Sepsis-associated genes from the Comparative Toxicogenomics Database (CTD) that overlapped with identified DEM targets were utilized for network construction. In total, 317 genes were found to be regulated by 10 DEMs (three upregulated, namely miR-4634, miR-4638-5p, and miR-4769-5p, and seven downregulated, namely miR-4299, miR-451a, miR181a-2-3p, miR-16-5p, miR-5704, miR-144-3p, and miR-1290). Overall hub genes (HIP1, GJC1, MDM4, IL6R, and ERC1) and for miR-16-5p (SYNRG, TNRC6B, and LAMTOR3) were identified based on centrality measures (degree, betweenness, and closeness). In vivo validation of miRNAs in lung tissue showed significantly downregulated expression of miR-16-5p corroborating with our computational findings, whereas expression of miR-181a-2-3p and miR-451a were found to be upregulated in contrast to the computational approach. In conclusion, the differential expression pattern of miRNAs and hub genes reported in this study may help to unravel many unexplored regulatory pathways, leading to the identification of critical molecular targets for increased prognosis, diagnosis, and drug efficacy in sepsis and associated organ injuries.

The Effects of Initial Procalcitonin Levels on Mortality Rates in Geriatric Patients Undergoing Surgery

Introduction

The aim of the current study is to investigate the relationship between mortality rate in geriatric patients undergoing surgery with preoperative serum levels of procalcitonin, C-reactive protein, and erythrocyte sedimentation rate.

Methods

This was a single-center retrospective study, including three groups with 101 patients, who are older than 65 years of age. A retrospective investigation was carried out from the laboratory information system for all groups from January to December 2018. Group 1 included patients who had surgery and then mortality within 30 days after surgery. Group 2 included hospitalized patients who had surgery and no mortality within 30 days after surgery. Group 3 included outpatient patients, who had suspicion for a bacterial infection and then no surgery or no mortality within 30 days.

Results

When three group comparisons were made for procalcitonin, C-reactive protein, and erythrocyte sedimentation rate values, the p-value of one-way analysis of variance (ANOVA) was higher than 0.05 for procalcitonin and lower than 0.05 for C-reactive protein and erythrocyte sedimentation rate, suggesting that one or more groups were significantly different. When post-hoc multiple comparison methods were applied, there were statistically significant differences between Groups 1 and 3 for C-reactive protein and erythrocyte sedimentation rate.

Conclusions

Procalcitonin levels do not predict mortality following surgery. C-reactive protein and erythrocyte sedimentation rate are more useful biomarkers predicting mortality in geriatric patients undergoing surgery.

Overview of Albumin and Its Purification Methods

As the most frequent plasma protein, albumin constitutes more than 50% of the serum proteins in healthy individuals. It has a key role in oncotic pressure maintenance and it is known as a versatile protein carrier for transportation of various endogenous and exogenous ligands. Reduced amounts of albumin in the body will lead to different kinds of diseases such as hypovolemia and hypoproteinemia. It also has various indications in shocks, burns, cardiopulmonary bypass, acute liver failure and etc. Further applications in research consist of cell culture supplement, drug delivery carrier and protein/drug stabilizer. So, the demand for albumin increased annually worldwide. Due to different applications of albumin, many efforts have been accomplished to achieve albumin during a long period of time. In this review, an overview of serum albumin and different purification methods are summarized.

Prognostic value of procalcitonin in patients after elective cardiac surgery: a prospective cohort study

Background

Procalcitonin (PCT) is a well-known prognostic marker after elective cardiac surgery. However, the impact of elevated PCT in patients with an initially uneventful postoperative course is still unclear. The aim of this study was to evaluate PCT levels as a prognostic tool for delayed complications after elective cardiac surgery.

Methods

A prospective study was performed in 751 patients with an apparently uneventful postoperative course within the first 24 h after elective cardiac surgery. Serum PCT concentration was taken the morning after surgery. All patients were screened for the occurrence of delayed complications. Delayed complications were defined by in-hospital death, intensive care unit readmission, or prolonged length of hospital stay (>12 days). Odds ratios (OR) [with 95% confidence interval (CI)] were calculated by logistic regression analyses and adjusted for confounders. Predictive capacity of PCT for delayed complications was calculated by ROC analyses. The cutoff value of PCT was derived from the Youden Index calculation.

Results

Among 751 patients with an initially uneventful postoperative course, 117 patients developed delayed complications. Serum PCT levels the first postoperative day were significantly higher in these 117 patients (8.9 ng/ml) compared to the remaining 634 (0.9 ng/ml; p < 0.001). ROC analyses showed that PCT had a high accuracy to predict delayed complications (optimal cutoff value of 2.95 ng/ml, AUC of 0.90, sensitivity 73% and specificity 97%). Patients with PCT levels above 2.95 ng/ml the first postoperative day had a highly increased risk of delayed complications (adjusted OR, 110.2; 95% CI 51.5–235.5; p < 0.001).

Conclusions

A single measurement of PCT seems to be a useful tool to identify patients at risk of delayed complications despite an initially uneventful postoperative course.

Soluble TREM-1 as a diagnostic and prognostic biomarker in patients with septic shock: an observational clinical study

OBJECTIVES

The impact of TREM-1-mediated inflammation was investigated in different inflammatory settings.

METHODS

Secondary analyses of an observational clinical pilot study, including 60 patients with septic shock, 30 postoperative controls and 30 healthy volunteers.

RESULTS

Plasma levels of sTREM-1 were found to identify patients with septic shock more effectively than procalcitonin and C-reactive protein. Moreover, sTREM-1 was identified to be an early predictor for survival in patients with septic shock.

CONCLUSION

Due to its diagnostic as well as prognostic value in sepsis syndrome, implementation of sTREM-1 measurements in routine diagnostics should be taken into account.

Serum levels of HSP70 and other DAMP proteins can aid in patient diagnosis after traumatic injury

Danger-associated molecular patterns (DAMPs) are activated by endogenous signals that originate from stressed, injured, or necrotic cells, signifying "danger" to the host. In this study, we evaluated the expression of the DAMP heat shock protein 70 (HSP70) in trauma patients with and without secondary infections. Levels of glucose (GLU), procalcitonin (PCT), total cholesterol (T-Chol), and white blood cell (WBC) counts were also evaluated at three time stages after trauma. Our analysis showed that the levels of serum HSP70 in patients with minor, moderate, and severe injuries were significantly higher than in healthy patients at each time point post-injury (P < 0.01), and levels of serum HSP70 in the severe injury group were significantly higher than in the minor injury group at 1-6 h after trauma (P = 0.047). HSP70 was correlated with GLU and was negatively correlated with T-Chol in the period 1-6 h after injury (P = 0.008/0.032). WBC and GLU were elevated after trauma, with mutual positive correlation (P < 0.001). PCT levels increased later than WBC counts and GLU levels; these levels were correlated at the two later time periods, 24-48 h and 60-90 h (P = 0.008/0.041). PCT continued to rise in patients with secondary infection, but PCT dropped at the third time period in patients without secondary infection. In summary, our results suggest that danger and stress theory can be used to predict severity of trauma.

The Perioperative Use of Albumin

Human serum albumin (HSA) is the predominant product of hepatic protein synthesis and one of the more abundant plasma proteins. HSA is a monomeric multidomain macromolecule, representing the main determinant of plasma oncotic pressure and the main modulator of fluid distribution between body compartments. HSA displays an essential role in maintaining the integrity of the vascular barrier. HSA is the most important antioxidant capacity of human plasma, in addition to its ability to protect the body from the harmful effects of heavy metals such as iron and copper and reduce their ability to produce reactive oxygen radicals. HSA is the main depot for nitric oxide (NO) transport in the blood. HSA represents the main carrier for fatty acids, affects pharmacokinetics of many drugs, and provides the metabolic modification of some drugs and displays pseudo-enzymatic properties. HSA has been widely used successfully for more than 50 years in many settings of perioperative medicine including hypovolemia, shock, burns, surgical blood loss, sepsis, and acute respiratory distress syndrome (ARDS). Recently, the use of HSA has shown a promising neuroprotective effect in patients with subarachnoid hemorrhage. The most recent evidence-based functions and uses of HSA in the perioperative period are reviewed in this chapter.

Retrospective study on prognostic importance of serum procalcitonin and amino-terminal pro-brain natriuretic peptide levels as compared to Acute Physiology and Chronic Health Evaluation IV Score on Intensive Care Unit admission, in a mixed Intensive Care Unit population

BACKGROUND

Timely decision making in Intensive Care Unit (ICU) is very essential to improve the outcome of critically sick patients. Conventional scores like Acute Physiology and Chronic Health Evaluation (APACHE IV) are quite cumbersome with calculations and take minimum 24 hours. Procalcitonin has shown to have prognostic value in ICU/Emergency department (ED) in disease states like pneumonia, sepsis etc. NTproBNP has demonstrated excellent diagnostic and prognostic importance in cardiac diseases. It has also been found elevated in non-cardiac diseases. We chose to study the prognostic utility of these markers on ICU admission.

SETTINGS AND DESIGN

Retrospective observational study.

MATERIALS AND METHODS

A Retrospective analysis of 100 eligible patients was done who had undergone PCT and NTproBNP measurements on ICU admission. Their correlations with all cause mortality, length of hospital stay, need for ventilator support, need for vasopressors were performed.

RESULTS

Among 100 randomly selected ICU patients, 28 were non-survivors. NTproBNP values on admission significantly correlated with all cause mortality (P = 0.036, AUC = 0.643) and morbidity (P = 0.000, AUC = 0.763), comparable to that of APACHE-IV score. PCT values on admission did not show significant association with mortality, but correlated well with morbidity and prolonged hospital length of stay (AUC = 0.616, P = 0.045).

CONCLUSION

The current study demonstrated a good predictive value of NTproBNP, in terms of mortality and morbidity comparable to that of APACHE-IV score. Procalcitonin, however, was found to have doubtful prognostic importance. These findings need to be confirmed in a prospective larger study.

Are there new approaches for diagnosis, therapy guidance and outcome prediction of sepsis?

Beside many efforts to improve outcome, sepsis is still one of the most frequent causes of death in critically ill patients. It is the most common condition with high mortality in intensive care units. The complexity of the septic syndrome comprises immunological aspects - i.e., sepsis induced immunosuppression - but is not restricted to this fact in modern concepts. So far, exact mechanisms and variables determining outcome and mortality stay unclear. Since there is no typical risk profile, early diagnosis and risk stratification remain difficult, which hinders rapid and effective treatment initiation. Due to the heterogeneous nature of sepsis, potential therapy options should be adapted to the individual. Biomarkers like C-reactive protein and procalcitonin are routinely used as complementary tools in clinical decision-making. Beyond the acute phase proteins, a wide bunch of promising substances and non-laboratory tools with potential diagnostic and prognostic value is under intensive investigation. So far, clinical decision just based on biomarker assessment is not yet feasible. However, biomarkers should be considered as a complementary approach.

Albumin—Beyond Fluid Replacement in Cardiopulmonary Bypass Surgery

Maintaining vascular barrier competence, preventing interstitial edema, and keeping microcirculation intact is crucial to achieve an optimal outcome in cardiopulmonary bypass surgery (CPB). Blood contact with roller pumps and foreign surfaces during CPB induces shear stress and a pressure drop across the pump boot that leads to transient systemic activation of the inflammatory and hemostatic systems. Moreover, patients after CPB often need volume resuscitation using the smallest possible amount of colloid solution because of fluid overload. For this purpose, human-derived albumin may be preferred over synthetic colloids because CPB priming with albumin preserves oncotic pressure, prevents platelet adhesion, and likely induces less consumption of coagulation factors. In patients with increased bleeding or renal failure, albumin is a safe alternative because of its minimal side effects. Large, randomized clinical trials comparing the benefit of albumin versus other fluids are warranted in the future to define albumin’s distinct role in select high-risk surgical populations.

Evaluation of prognostic value of selected biochemical markers in surgically treated patients with acute mediastinitis

BACKGROUND

Monitoring of biochemical markers of inflammation in acute mediastinitis (AM) can be useful in the modification of treatment. This study was a retrospective evaluation of selected biochemical parameters with negative impact on the prognosis in surgically treated patients.

MATERIAL/METHODS

There were 44 consecutive patients treated surgically due to AM of differentiated etiology. Selected biochemical markers (WBC, RBC, HGB, HCT, PLT, CRP, PCT, ionogram, protein and albumins) were assessed before surgery and on the 3rd day after surgery. ANOVA was applied to find factors influencing observations. Numerical data [laboratory parameters] were compared by means of medians.

RESULTS

The overall hospital mortality rate was 31.82%. In the group of dead patients, there were observed statistically significant lower mean preoperative values of RBC [p=0.0090], HGB [p=0.0286], HCT [p=0.0354], protein [p= 0.0037], albumins [p=0.0003] and sodium [p<0.0001] and elevated values of CRP [P=0.0107] and PCT p<0.0001]. High level of inflammatory markers on day 3 after surgery was found to increase the risk of death - for WBC (by 67%), for CRP (by 88%) and for PCT (by 100%).

CONCLUSIONS

Poor prognosis was more frequent in patients with preoperative high levels of CRP, PCT, anemia, hypoproteinemia and hyponatremia. The risk of death increases significantly if in the immediate postoperative period no distinct decrease in WBC count and of the CRP and PCT level is observed. In such a situation the patients should be qualified earlier for broadened diagnostic workup and for reoperation.

Predictors of survival in sepsis: what is the best inflammatory marker to measure?

PURPOSE OF REVIEW

Sepsis is relevant due to its high morbidity and mortality. For both sepsis diagnosis and outcome prediction many biomarkers have been described in the literature. Most of these markers are objects of scientific interest rather than being introduced into daily clinical practice. However, due to their unspecific character and their insufficient predictive value for the individual person, research focus is still on new aspects in sepsis-related biomarkers.

RECENT FINDINGS

Beyond the widely used acute-phase proteins C-reactive protein (CRP) and procalcitonin (PCT), many new molecules have been studied deriving from different organs or cells affected, due to the systemic nature of sepsis. Cytokines, coagulation factors/characteristics, vasoactive hormones, and several others have been recently proved to be relevant in sepsis syndrome and probably useful for outcome prediction. However, single time point measurements may be less predictive than consideration of the time-dependent course of parameters. Clinical decision just based on a biomarker is still not feasible because of the huge inter-individual differences in the inflammatory response.

SUMMARY

Many biomarkers display relevant correlation with the clinical outcome of patients with severe sepsis and septic shock. Consideration of their time courses may be more reliable than absolute levels. Clinical decision should not be based only on biomarkers but organ dysfunctions, for example, should also be taken into account.

Serum microRNA signatures identified by Solexa sequencing predict sepsis patients' mortality: a prospective observational study

BACKGROUND

Sepsis is the leading cause of death in Intensive Care Units. Novel sepsis biomarkers and targets for treatment are needed to improve mortality from sepsis. MicroRNAs (miRNAs) have recently been used as finger prints for sepsis, and our goal in this prospective study was to investigate if serum miRNAs identified in genome-wide scans could predict sepsis mortality.

METHODOLOGY/PRINCIPAL FINDINGS

We enrolled 214 sepsis patients (117 survivors and 97 non-survivors based on 28-day mortality). Solexa sequencing followed by quantitative reverse transcriptase polymerase chain reaction assays was used to test for differences in the levels of miRNAs between survivors and non-survivors. miR-223, miR-15a, miR-16, miR-122, miR-193*, and miR-483-5p were significantly differentially expressed. Receiver operating characteristic curves were generated and the areas under the curve (AUC) for these six miRNAs for predicting sepsis mortality ranged from 0.610 (95%CI: 0.523-0.697) to 0.790 (95%CI: 0.719-0.861). Logistic regression analysis showed that sepsis stage, Sequential Organ Failure Assessment scores, Acute Physiology and Chronic Health Evaluation II scores, miR-15a, miR-16, miR-193b*, and miR-483-5p were associated with death from sepsis. An analysis was done using these seven variables combined. The AUC for these combined variables' predictive probability was 0.953 (95% CI: 0.923-0.983), which was much higher than the AUCs for Acute Physiology and Chronic Health Evaluation II scores (0.782; 95% CI: 0.712-0.851), Sequential Organ Failure Assessment scores (0.752; 95% CI: 0.672-0.832), and procalcitonin levels (0.689; 95% CI: 0.611-0.784). With a cut-off point of 0.550, the predictive value of the seven variables had a sensitivity of 88.5% and a specificity of 90.4%. Additionally, miR-193b* had the highest odds ratio for sepsis mortality of 9.23 (95% CI: 1.20-71.16).

CONCLUSION/SIGNIFICANCE

Six serum miRNA's were identified as prognostic predictors for sepsis patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01207531.

Diagnostic and prognostic biomarkers of sepsis in critical care

Sepsis is a leading cause of mortality in critically ill patients. Delay in diagnosis and initiation of antibiotics have been shown to increase mortality in this cohort. However, differentiating sepsis from non-infectious triggers of the systemic inflammatory response syndrome (SIRS) is difficult, especially in critically ill patients who may have SIRS for other reasons. It is this conundrum that predominantly drives broad-spectrum antimicrobial use and the associated evolution of antibiotic resistance in critical care environments. It is perhaps unsurprising, therefore, that the search for a highly accurate biomarker of sepsis has become one of the holy grails of medicine. Procalcitonin (PCT) has emerged as the most studied and promising sepsis biomarker. For diagnostic and prognostic purposes in critical care, PCT is an advance on C-reactive protein and other traditional markers of sepsis, but is not accurate enough for clinicians to dispense with clinical judgement. There is stronger evidence, however, that measurement of PCT has a role in reducing the antibiotic exposure of critical care patients. For units intending to incorporate PCT assays into routine clinical practice, the cost-effectiveness of this is likely to depend on the pre-implementation length of an average antibiotic course and the subsequent impact of implementation on emerging antibiotic resistance. In most of the trials to date, the average baseline duration of the antibiotic course was longer than is currently standard practice in many UK critical care units. Many other biomarkers are currently being investigated. To be highly useful in clinical practice, it may be necessary to combine these with other novel biomarkers and/or traditional markers of sepsis.

Nutritional challenges and outcomes after surgery for congenital heart disease

PURPOSE OF REVIEW

Adequate nutrition is crucial in children after surgery for congenital heart disease. We address selected nutritional and caloric requirements for children in the perioperative period before and after cardiac surgery and explore nutritional interdependence with other system functions. Recommendations based on our current practice are made at the end of each section.

RECENT FINDINGS

Early identification of deficient oropharyngeal motor skills and vocal cord dysfunction is crucial to establish enteral nutrition safely and has been demonstrated to improve clinical outcomes. The use of prealbumin as a marker of nutritional state should be accompanied by C-reactive protein given the influence of inflammation on its levels. Insulin infusions may improve outcomes in patients with postoperative hyperglycemia. Trace element abnormalities and early identification of immune-compromised states can aid in reducing morbidity in children after cardiac surgery. Use of feeding protocols and a home surveillance system for hypoplastic left heart syndrome improves outcomes.

SUMMARY

Adequate nutritional support in children after cardiac surgery is a challenge. Attention to lesion-specific feeding problems, supplementation of trace elements and minerals, and an organized approach to pace, timing, and type of feeding are beneficial.

Postoperative hypoalbuminemia is associated with outcome in patients undergoing off-pump coronary artery bypass graft surgery

OBJECTIVE

The authors aimed to investigate whether immediate postoperative hypoalbuminemia could be associated with outcomes after off-pump coronary artery bypass graft (OPCAB) surgery.

DESIGN

A retrospective analysis of the medical data.

SETTING

Cardiac operating room and adult cardiovascular intensive care unit at a single institution.

PARTICIPANTS

Six hundred ninety adult patients underwent elective OPCAB surgery over a 30-month period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

To evaluate the clinical relevance of immediate postoperative hypoalbuminemia, the lowest serum albumin level measured over the first 12 hours postoperatively was recorded. A cutoff point was calculated by the area under the curve in the receiver operating characteristic plot for 30-day adverse events including death. Patients were classified according to the cutoff value, and outcomes were compared between groups using propensity score-matching analysis. The impact of immediate postoperative hypoalbuminemia on OPCAB outcome was investigated using multivariate analysis. The cutoff value for immediate postoperative albumin concentration for predicting 30-day adverse events was 2.3 g/dL. Immediate postoperative hypoalbuminemia (<2.3 g/dL) was associated independently with postoperative respiratory failure (odds ratio [OR] = 8.85, p = 0.04), wound infection (OR = 4.44, p = 0.04), the need for an intra-aortic balloon pump after the operation (OR = 13.7, p = 0.02), renal failure (OR = 7.98, p = 0.01), reoperation for bleeding (OR = 4.33, p = 0.05), and the need for inotropes in the intensive care unit (OR = 1.79, p = 0.02).

CONCLUSIONS

Immediate postoperative hypoalbuminemia was associated with poorer outcomes in OPCAB patients. Monitoring of albumin levels after OPCAB could identify patients at risk for short-term adverse events.

Transfusion has no effect on recurrence in hepatitis C after liver transplantation

BACKGROUND

The literature suggests that blood product transfusions have a negative impact on the survival of liver transplant patients. We investigated the impact of intraoperative blood product usage on the survival of liver transplantation patients being transplanted for hepatitis C-related end-stage liver disease. In addition, we analyzed a potentially more sensitive metric, namely disease recurrence and fibrosis progression, obtained from follow-up liver biopsies.

METHODS

We retrospectively studied 194 consecutive patients with hepatitis C virus (HCV) undergoing liver transplantation. To investigate the effect of red blood cell (RBC) or platelet transfusions on post-transplant HCV recurrence, hepatic biopsy data from 4 months and 1 year after transplantation were studied. In addition, survival data were analyzed.

RESULTS

There was no effect of intraoperative RBC or platelet transfusion on either 1- or 5-year patient survival following liver transplantation. There was no difference in HCV disease recurrence or progression of hepatic fibrosis at 4 months or 1 year attributable either to RBC or to platelet transfusion.

CONCLUSION

This study was not able to confirm an effect on the survival of HCV-infected liver transplant patients related to intraoperative transfusion of RBCs or platelets. In addition, these transfusions had no effect on HCV recurrence or fibrosis progression. This is not to condone a liberal transfusion practice, but rather to reassure that when clinically indicated, transfusion does not have a significant impact on patient survival or disease recurrence in HCV-infected liver transplant patients.

Grading of severity of the condition in burn patients by serum protein and albumin/globulin studies

Capillary permeability increases after inflammation with consequent leak of fluid, electrolytes, and proteins. The albumin molecule size being smaller (69 kDa) than the globulin molecule (90-156 kDa) will leak relatively at an early stage of the disease (with moderate increase in capillary pore size) than globulin leading to albumin/globulin reversal. In cases with severe permeability changes with rapid progression to larger pore size with simultaneous leak of both albumin and globulin, albumin/globulin reversal will not occur. In this study estimation the serum protein and albumin/globulin (A/G) ratio at frequent intervals was done to grade the severity of the condition of burn patients by assessing the severity of capillary leak.A total of 61 admitted patients (from March 2002 to December 2004) based on the protein values were divided into 3 groups (group 1: 6-8 g/dL, group 2: 5.1-5.9 g/dL, group 3: < or =5.0 g/dL), and all the patients who showed change in their protein levels during the study were shifted to appropriate group and were classified as group shifters. The mean survival time and mortality of various groups were compared, and A/G ratio of all the expired cases was analyzed.Group 3 patients showed higher mortality (95%) as compared to that in other groups (group 1 and 2: 0% each and group shifters: 30.2%). Median survival time of group 3 was significantly low as compared to that of group 1 (P < 0.0026), group 2 (P < 0.0006), and group shifters (P < 0.0000). In group shifters the mean time (days) required for shifting from one group to other just before death or discharge in survivors was significantly higher than that in expired cases. Of 26 cases expired during the study, initial A/G ratio at the time of first assigning the group was not reversed in 22 cases (84.6%).The study concluded that the severity (indicated by lower serum protein values) and speed (judged by A/G ratio changes and median survival time analysis) of capillary permeability changes were associated with high mortality, and therefore, it is possible to grade the severity of the condition in burn patients.

Predictive value of procalcitonin, interleukin-6, and C-reactive protein for survival in postoperative patients with severe sepsis

PURPOSE

To prospectively evaluate the performance of procalcitonin (PCT), interleukin-6 (IL-6), and C-reactive protein (CRP) as percentage of baseline (POB) in predicting hospital survival, we studied 64 consecutive, postoperative patients with severe sepsis.

MATERIALS AND METHODS

Plasma PCT, IL-6, and CRP were serially measured from day 1 (onset of sepsis) to day 14 in parallel with clinical data until day 28. Multivariate logistic regression and univariate analysis of predictive accuracy of PCT-, IL-6-, and CRP-POB were performed. Newly derived binary prediction rules were evaluated by calculating sensitivity, specificity, positive predictive value, and negative predictive value.

RESULTS

In survivors, PCT and IL-6 significantly decreased from days 1 to 14, whereas CRP did not. In nonsurvivors, the inflammation markers mostly increased within the second week. At day 7, logistic regression analysis revealed PCT-POB as an independent determinant for survival. Especially, PCT-POB not exceeding 50% and PCT-POB not exceeding 25% with CRP-POB not exceeding 75% on day 7 indicated a favorable outcome with a positive predictive value/sensitivity of 75%/97% and 92%/67%, respectively. In comparison, pretest likelihood to survive by day 28 and observed survival rate were 60% and 67%, respectively.

CONCLUSIONS

Prediction rules of decrease in PCT-POB on day 7 in combination with CRP-POB may serve to monitor efficacy and guide duration of therapy in critically ill patients.

Relevance of albumin in modern critical care medicine

The relevance of albumin administration in the critical care setting remains controversial. We know that albumin has numerous important physiological effects and many potentially beneficial effects in critical illness. We also know that hypoalbuminaemia is common in critically ill patients and is associated with worse outcomes. And we know that routine administration of albumin for fluid resuscitation is not warranted. Albumin may be useful in some patients, especially those with hypoalbuminaemia at risk of complications or those with liver insufficiency. Further studies are needed to clarify what precise role albumin has in today's ICU.

Accuracy of procalcitonin for outcome prediction in unselected postoperative critically ill patients

The importance of postoperative procalcitonin (PCT) measurements for outcome prediction is currently controversial. Conflicting results have been obtained for patients after polytrauma, sepsis, peritonitis, or cardiac surgery and may result from incomplete adjustment for important confounders or from nonlinear PCT effects. We retrospectively analyzed the association of PCT concentration with postoperative mortality, morbidity, and length of stay in an unselected series of 220 consecutive patients who required postoperative intensive care unit therapy or surveillance. Biochemical markers were measured on the first day after intensive care unit admission. Results were adjusted for various confounding variables (Acute Physiology and Chronic Health Evaluation II score, underlying disease), and test accuracy was evaluated by receiver operating characteristic statistics. We found a significant nonlinear, logarithmic association between PCT concentration and outcome. After adjustment for relevant covariates, PCT was an independent determinant of mortality, combined mortality/morbidity, and postoperative hospital length of stay in survivors. At mortality analysis, the predictive power of PCT was superior to that of Acute Physiology and Chronic Health Evaluation II score and of IL-6 (optimal cutoff point, 1.44 ng/mL; sensitivity, 80.8%; specificity, 80.4%). The use of PCT was comparable to that of other prognostic markers when combined mortality/morbidity were examined. Our results suggest that PCT may deserve further testing as a prognostic tool in unselected, critically ill, surgical patients.

Is albumin administration in hypoalbuminemic elderly cardiac surgery patients of benefit with regard to inflammation, endothelial activation, and long-term kidney function?

BACKGROUND

Because patients with low albumin levels may benefit from human albumin (HA) administration, we studied correction of hypovolemia with HA in hypoalbuminic elderly cardiac surgery patients.

METHODS

In a prospective, randomized study, 50 patients aged >80 yr undergoing cardiac surgery using cardiopulmonary bypass with a preoperative serum albumin concentration of <3.5 mg/dL, received either 5% HA (n = 25) or hydroxyethyl starch (6% HES 130/0.4) (n = 25). Volume was added to the priming (500 mL) and given until the morning of the second postoperative day to keep pulmonary capillary wedge pressure or central venous pressure between 12 and 14 mm Hg.

RESULTS

Inflammatory response (interleukins-6, -10), endothelial activation (intercellular adhesion molecule-1), and kidney function (including glutathione transferase-alpha and neutrophil gelatinase-associated lipocalin) were measured after induction of anesthesia, 5 h after surgery, and the first and second postoperative day. A follow-up, approximately 60 days after discharge from the hospital, was done. Two thousand nine hundred eighty +/- 430 mL of HA and 3060 +/- 680 mL of HES 130/0.4 were given. Serum albumin concentration was significantly increased by HA (to 4.5 +/- 0.3 mg/dL). Serum creatinine, glomerular filtration rate, and urinary levels of alpha-glutathione transferase and neutrophil gelatinase-associated lipocalin were not different in the HA-compared to the HES-treated patients. The inflammatory response was similar in both groups, whereas endothelial activation was less in the HES group. None of the patients developed renal failure requiring renal replacement therapy.

CONCLUSION

Use of HA in hypoalbuminemic cardiac surgery patients aged >80 yr was without benefit with regard to inflammatory response, endothelial activation, and renal function compared to 6% HES 130/0.4.

Tricuspid valve replacement after cardiac transplantation

BACKGROUND

Tricuspid regurgitation (TR) occurs commonly in transplanted hearts. Although theoretically attractive, tricuspid valve replacement (TVR) has not been widely investigated as a possible therapy in post-transplant patients. The purpose of this study was to determine the safety of TVR in heart transplant patients and its effects on measurable clinical endpoints.

METHODS

We acquired data by both retrospective chart review and prospective data collection in all patients who underwent TVR after cardiac transplantation.

RESULTS

Nine patients were identified and followed for a period of six months. The age of patients at time of TVR was 62 +/- 6.1 yr and their average time since transplantation was 12 +/- 3.2 yr. Most patients demonstrated a reduction in their furosemide dose (105 +/- 63 mg/d pre-TVR vs. 67.5 +/- 65 mg/d post-TVR, p = 0.001) with a reduction in serum creatinine levels (188 +/- 72 micromol/L pre-TVR vs. 143 +/- 42 micromol/L post-TVR, p = 0.06). Additionally, we found a significant improvement in albumin values (32 +/- 5 g/L pre-TVR vs. 42 +/- 3 g/L post-TVR, p = 0.002) as well as an improvement in total bilirubin (35 +/- 18 micromol/L pre-TVR vs. 18 +/- 5 micromol/L post-TVR, p = 0.05). There was only one death in our series, in the only patient with known severe graft atherosclerosis.

CONCLUSIONS

TVR appears to be a safe procedure in patients without severe graft atherosclerosis with improvements in serum creatinine, albumin and total bilirubin values, in addition to a reduction in furosemide dose. This may reflect improved forward flow, improved symptomatology from TR as well as possible beneficial effects on nutritional status.

Albumin administration improves organ function in critically ill hypoalbuminemic patients: A prospective, randomized, controlled, pilot study

OBJECTIVE

To test the hypothesis that administration of albumin to correct hypoalbuminemia might have beneficial effects on organ function in a mixed population of critically ill patients.

DESIGN

: Prospective, controlled, randomized study.

SETTING

Thirty-one-bed, mixed medicosurgical department of intensive care.

PATIENTS

All adult patients with a serum albumin concentration < or =30 g/L were assessed for eligibility. Principal exclusion criteria were expected length of stay <72 hrs, life expectancy <3 months or a do-not-resuscitate order, albumin administration in the preceding 24 hrs, or evidence of fluid overload.

INTERVENTIONS

The 100 patients were randomized to receive 300 mL of 20% albumin solution on the first day, then 200 mL/day provided their serum albumin concentration was <31 g/dL (albumin group), or to receive no albumin (control group).

MEASUREMENTS AND MAIN RESULTS

The primary outcome was the effect of albumin administration on organ function as assessed by a delta Sequential Organ Failure Assessment score from day 1 to day 7 (or the day of intensive care discharge or death, whichever came first). The two groups of 50 patients were comparable at baseline for age, gender, albumin concentration, and Acute Physiology and Chronic Health Evaluation II score. Albumin concentration did not change over time in the control group but increased consistently in the albumin group (p < .001). Organ function improved more in the albumin than in the control group (p = .026), mainly due to a difference in respiratory, cardiovascular, and central nervous system components of the Sequential Organ Failure Assessment score. Diuretic use was identical in both groups, but mean fluid gain was almost three times higher in the control group (1679 +/- 1156 vs. 658 +/- 1101 mL, p = .04). Median daily calorie intake was higher in the albumin than in the control group (1122 [935-1158] vs. 760 [571-1077] kcal, p = .05).

CONCLUSIONS

Albumin administration may improve organ function in hypoalbuminemic critically ill patients. It results in a less positive fluid balance and a better tolerance to enteral feeding.

Serum osmolality and outcome in intensive care unit patients

BACKGROUND

The aim of the present study was to compare 16 routine clinical and laboratory parameters, acute physiologic and chronic health evaluation (APACHE) and sequential organ failure assessment (SOFA) score for their value in predicting mortality during hospital stay in patients admitted to a general intensive care unit (ICU).

METHODS

A retrospective observational clinical study was carried out in a 15-bed ICU in a university hospital. Nine hundred and thirty-three consecutive patients with ICU stay > 24 h (36.2% surgical, 29.1% medical and 34.7% trauma) were observed. Blood sampling, patient surveillance and data collection were performed. The primary outcome was mortality in the hospital. We used receiver operating characteristic (ROC) analyses and logistic regression to compare the 16 relevant parameters, APACHE II and SOFA scores.

RESULTS

Two hundred and thirty-three out of the 933 patients died (mortality 25.0%). One laboratory parameter, serum osmolality [area under the curve (AUC) 0.732] had a predictive value for mortality which lay between that of APACHE II (AUC 0.784) and SOFA (AUC 0.720) scores. When outcome prediction was restricted to long-term patients (ICU stay > 5 days), serum osmolality (AUC 0.711) performed better than either of the standard scores (APACHE AUC 0.655, SOFA AUC 0.636). Using logistic regression analysis, the association of clinical parameters, age and diagnosis group with mortality was determined.

CONCLUSION

Elevated serum osmolality at ICU admission is associated with an increased mortality risk in critically ill patients. Serum osmolality is cheaper and more rapid to determine than the scoring systems. However, further studies are needed to evaluate the predictive value of serum osmolality in different patient populations.

Procalcitonin as a diagnostic test for sepsis in critically ill adults and after surgery or trauma: a systematic review and meta-analysis

OBJECTIVE

To quantify the accuracy of serum procalcitonin as a diagnostic test for sepsis, severe sepsis, or septic shock in adults in intensive care units or after surgery or trauma, alone and compared with C-reactive protein. To draw and compare the summary receiver operating characteristics curves for procalcitonin and C-reactive protein from the literature.

DATA SOURCE

MEDLINE (keywords: procalcitonin, intensive care, sepsis, postoperative sepsis, trauma); screening of the literature.

STUDY SELECTION

Meta-analysis of all 49 published studies in medical, surgical, or polyvalent intensive care units or postoperative wards. Children, medical patients, and immunocompromised patients were excluded.

DATA EXTRACTION

Thirty-three studies fulfilled inclusion criteria (3,943 patients, 1,828 males, 922 females; mean age: 56.1 yrs; 1,825 patients with sepsis, severe sepsis, or septic shock; 1,545 with only systemic inflammatory response syndrome); eight studies could not be analyzed statistically. Global mortality rate was 29.3%.

DATA SYNTHESIS

Global odds ratios for diagnosis of infection complicated by systemic inflammation were 15.7 for the 25 studies (2,966 patients) using procalcitonin (95% confidence interval, 9.1-27.1) and 5.4 for the 15 studies (1,322 patients) using C-reactive protein (95% confidence interval, 3.2-9.2). The summary receiver operating characteristics curve for procalcitonin was better than for C-reactive protein. In the 15 studies using both markers, the Q* value (intersection of summary receiver operating characteristics curve with the diagonal line where sensitivity equals specificity) was significantly higher for procalcitonin than for C-reactive protein (0.78 vs. 0.71, p = .02), the former test showing better accuracy.

CONCLUSIONS

Procalcitonin represents a good biological diagnostic marker for sepsis, severe sepsis, or septic shock, difficult diagnoses in critically ill patients. Procalcitonin is superior to C-reactive protein. Procalcitonin should be included in diagnostic guidelines for sepsis and in clinical practice in intensive care units.

Endocrine markers of severity and prognosis in critical illness

The cellular processes that unfold in critical illness involve a variety of circulating substances, that may provide clinically relevant insight into the severity and outcome. Among hormonal markers, cortisol, several thyroid-related substances, as well as natriuretic peptides are discussed in this review. Glucose and lipids constitute metabolic markers, the identification and treatment of the former has been of particular importance. Among immune markers, both proinflammatory and anti-inflammatory cytokines, such as interleukin-6, contribute essential prognostic information. Finally, the complement and coagulation pathways also provide unique insight into this complex and heterogeneous process.

Diagnostic value and prognostic implications of serum procalcitonin after cardiac surgery: a systematic review of the literature

INTRODUCTION

Systemic inflammatory response syndrome is common after surgery, and it can be difficult to discriminate between infection and inflammation. We performed a review of the literature with the aims of describing the evolution of serum procalcitonin (PCT) levels after uncomplicated cardiac surgery, characterising the role of PCT as a tool in discriminating infection, identifying the relation between PCT, organ failure, and severity of sepsis syndromes, and assessing the possible role of PCT in detection of postoperative complications and mortality.

METHODS

We performed a search on MEDLINE using the keyword 'procalcitonin' crossed with 'cardiac surgery,' 'heart,' 'postoperative,' and 'transplantation.' Our search was limited to human studies published between January 1990 and June 2006.

RESULTS

Uncomplicated cardiac surgery induces a postoperative increase in serum PCT levels. Peak PCT levels are reached within 24 hours postoperatively and return to normal levels within the first week. This increase seems to be dependent on the surgical procedure and on intraoperative events. Although PCT values reported in infected patients are generally higher than in non-infected patients after cardiac surgery, the cutoff point for discriminating infection ranges from 1 to 5 ng/ml, and the dynamics of PCT levels over time may be more important than absolute values. PCT is superior to C-reactive protein in discriminating infections in this setting. PCT levels are higher with increased severity of sepsis and the presence of organ dysfunction/failure and in patients with a poor outcome or in those who develop postoperative complications. PCT levels typically remain unchanged after acute rejection but increase markedly after bacterial and fungal infections. Systemic infections are associated with greater PCT elevation than is local infection. Viral infections are difficult to identify based on PCT measurements.

CONCLUSION

The dynamics of PCT levels, rather than absolute values, could be important in identifying patients with infectious complications after cardiac surgery. PCT is useful in differentiating acute graft rejection after heart and/or lung transplantation from bacterial and fungal infections. Further studies are needed to define cutoff points and to incorporate PCT levels in useful prediction models.

Serum albumin and clinical outcome in pediatric cardiac surgery

OBJECTIVE

We evaluated the behavior of serum albumin concentrations in response to metabolic stress that is associated with cardiac surgery and the role of this protein as a predictor of clinical outcome in children at high surgical risk who undergo operative correction of congenital heart defects.

METHODS

Serum albumin concentrations were measured in 30 children who had heart disease and were at high surgical risk. Analyses were performed before surgery, on the second postoperative day, and on discharge from the intensive care unit. Preoperative serum concentrations of albumin were compared with those of a control group that consisted of 20 healthy and well-nourished children.

RESULTS

Preoperative albumin concentrations of patients were lower than those of the control group (3.4+/-0.25 g/dL versus 4.0+/-0.18 g/dL, P<0.05). Serum levels decreased on the second postoperative day and at discharge from the intensive care unit (3.1+/-0.65 g/dL and 3.2+/-0.44 g/dL, P<0.05) compared with preoperative concentrations. Preoperative concentrations lower than 3.0 g/dL were associated with increased postsurgical infection (P=0.0026) and with increased mortality (P=0.0138). Patients whose postoperative levels were lower than 3.0 g/dL had longer hospital stays compared with those whose concentrations were higher than 3.0 g/dL (14.5+/-1.3 d versus 10+/-2.2 d, P<0.05).

CONCLUSION

The results suggest that hypoalbuminemia is common among children who have heart disease and are at high surgical risk, and serum albumin concentrations lower than 3 g/dL may be related to outcome in the period after cardiac surgery.