Body mass index and albumin in the preoperative evaluation of cardiac surgery patients

Body Mass Index and All-Cause Mortality in Elderly Patients with Percutaneous Coronary Intervention: A Meta-Analysis

INTRODUCTION

The "obesity paradox" in elderly patients suffering from percutaneous coronary intervention (PCI) remains a source of controversy. The present meta-analysis focused on exploring the real existence of "obesity paradox" in these patients.

METHODS

As of November 2022, PubMed, Cochrane, and Embase databases were comprehensively searched to identify articles reporting all-cause mortality according to diverse body mass index (BMI) categories after PCI among the old cases developing coronary artery disease (CAD). Summary estimates of relative risks (RRs) were assigned to four BMI groups, including underweight, normal weight, overweight, and obesity groups.

RESULTS

There were altogether nine articles involving 25,798 cases selected for further analysis. Relative to normal weight group, overweight and obesity groups had decreased all-cause mortality (RR: 0.86, 95% CI: 0.77-0.95 for overweight group; RR: 0.57, 95% CI: 0.40-0.80 for obesity group), while underweight group had elevated all-cause mortality (RR: 1.52, 95% CI: 1.01-2.29).

CONCLUSION

Our study revealed an "obesity paradox" relation of BMI with all-cause mortality in elderly cases receiving PCI. In comparison with normal weight group, overweight and obesity groups had decreased all-cause mortality, while underweight group had increased all-cause mortality.

Preoperative prognostic nutritional index is an independent indicator for perioperative prognosis in coronary artery bypass grafting patients

OBJECTIVES

The prognostic nutritional index is widely used for surgery prognosis, but the association between preoperative prognostic nutritional index and short-term prognosis for coronary artery bypass grafting surgery and the profiles of perioperative prognostic nutritional index remain unclear.

METHODS

This study retrospectively enrolled a total of 879 adult patients undergoing coronary artery bypass grafting surgery in the Shanghai Chest Hospital from 2006 to 2022. The prognostic nutritional index was calculated based on serum albumin and peripheral lymphocyte count. In-hospital mortality, demographic characteristics, blood biochemistry parameters, cardiovascular medical history, and physical examination results were collected from the hospital information system. The propensity score matching method and multivariate logistic regression were used to detect the association between preoperative prognostic nutritional index and in-hospital mortality.

RESULTS

Patients were divided into a high-prognostic nutritional index group (n = 500) and a low-prognostic nutritional index group (n = 379), using a cutoff value of 48.1 according to receiver operating characteristic curve analysis. The propensity score matching-adjusted mean prognostic nutritional index levels decreased from 48.35 before the operation to 34.04 an in ≤24 h after the operation and rebounded to 43.36 before discharge. High preoperative prognostic nutritional index was inversely associated with in-hospital mortality for coronary artery bypass grafting surgery (odds ratio = 0.86; 95% CI, 0.77-0.97) in propensity score matching-adjusted multivariate logistic regression.

CONCLUSIONS

Preoperative prognostic nutritional index is an independent indicator for in-hospital mortality of for coronary artery bypass grafting surgery, and the variation trend of prognostic nutritional index during perioperation tends to be U-shaped.

The importance of liver function assessment before cardiac surgery: A narrative review

The demand for cardiac surgery procedures is increasing globally. Thanks to an improvement in survival driven by medical advances, patients with liver disease undergo cardiac surgery more often. Liver disease is associated with the development of heart failure, especially in patients with advanced cirrhosis. Cardiovascular risk factors can also contribute to the development of both cardiomyopathy and liver disease and heart failure itself can worsen liver function. Despite the risk that liver disease and cirrhosis represent for the perioperative management of patients who undergo cardiac surgery, liver function is often not included in common risk scores for preoperative evaluation. These patients have worse short and long-term survival when compared with other cardiac surgery populations. Preoperative evaluation of liver function, postoperative management and close postoperative follow-up are crucial for avoiding complications and improving results. In the present narrative review, we discuss the pathophysiological components related with postoperative complications and mortality in patients with liver disease who undergo cardiac surgery and provide recommendations for the perioperative management.

Effectiveness of intensive perioperative nutrition therapy among adults undergoing gastrointestinal and oncological surgery in a public hospital: study protocol for a pragmatic randomized control trial

Background

Perioperative malnutrition is common in patients undergoing gastrointestinal-oncology surgery and is associated with longer hospital stays, increased postoperative complications, poorer quality of life, and lower survival rates. Current practice emphasizes the role of early perioperative nutrition therapy as an early intervention to combat the postoperative complications of patients and the implementation is now widely adopted. However, there is still a lack of research on determining the effectiveness of intensive nutrition therapy and providing ONS perioperative locally. This becomes the significance of this study and serves as a basis for management and guideline in the local hospital settings.

Methods

This is a pragmatic randomized control trial study where elective admitted patients will be randomly divided into the intervention (SS) or control (NN) group. All data will be collected during a face-to-face interview, anthropometric measurement, blood sampling (albumin, white blood count, hemoglobin, and c-reactive protein), handgrip strength, and postoperative complications. Group SS will be receiving a tailored lifestyle and intensively supplemented with oral nutrition support as compared to Group NN that will receive standard medical care. The primary outcome for this study is the length of stay in the hospital. Additional outcome measures are changes in biochemical profile and nutritional and functional status. The effects of intervention between groups on the outcome parameters will be analyzed by using the SPSS General Linear Model (GLM) for the repeated measure procedure.

Discussion

The intervention implemented in this study will serve as baseline data in providing appropriate nutritional management in patients undergoing gastrointestinal and oncological surgery.

Trial registration

ClinicalTrials.gov Protocol Registration and Results System (PRS) NCT04347772. Registered on 20 November 2019.

The Association between Serum Albumin and Post-Operative Outcomes among Patients Undergoing Common Surgical Procedures: An Analysis of a Multi-Specialty Surgical Cohort from the National Surgical Quality Improvement Program (NSQIP)

While studies have demonstrated an association between preoperative hypoalbuminemia and adverse clinical outcomes, the optimal serum albumin threshold for risk-stratification in the broader surgical population remains poorly defined. We sought define the optimal threshold of preoperative serum albumin concentration for risk-stratification of adverse post-operative outcomes. Using the American College of Surgeons National Surgical Quality Improvement Program Database, we identified 842,672 patients that had undergone a common surgical procedure in one of eight surgical specialties. An optimal serum albumin concentration threshold for risk-stratification was determined using receiver-operating characteristic analysis. Multivariable logistic regression analysis was used to evaluate the odds of adverse surgical events; a priori defined subgroup analyses were performed. A serum albumin threshold of 3.4 g/dL optimally predicted adverse surgical outcomes in the broader cohort. After multivariable analysis, patients with hypoalbuminemia had increased odds of death within 30 days of surgery (odds ratio [OR] 2.01, 95% confidence interval [CI] 1.94–2.08). Hypoalbuminemia was associated with greater odds of primary adverse events among patients with disseminated cancer (OR 2.03, 95% CI 1.88–2.20) compared to patients without disseminated cancer (OR 1.47, 95% CI 1.44–1.51). The standard clinical threshold for hypoalbuminemia is the optimal threshold for preoperative risk assessment.

Pre-Habilitation of Cardiac Surgical Patients, Part 2: Frailty, Malnutrition, Respiratory disease, Alcohol/Smoking cessation and Depression

The concept of "pre-habilitation" comprises screening for and identification of pre-existing disorders followed by medical optimization. This is performed for many types of surgeries, but may have profound impacts on outcomes, particularly in cardiac surgery given the multiple comorbidities typically carried by these patients. Components of pre-habilitation include direct medical intervention by preoperative specialists as well as significant care coordination and shared decision-making. In this second part of a two-part review, the authors describe existing evidence to support the optimization of various preoperative problems and present a few institutional protocols utilized at out center for cardiac presurgical care. This second installment will focus on alcohol and smoking cessation and the management of frailty, malnutrition, respiratory disease, and depression.

The Predictive Value of Preoperative Albumin–Globulin Ratio for Systemic Inflammatory Response Syndrome After Percutaneous Nephrolithotomy

Purpose

Methods

Results

Conclusion

Preoperative hypoalbuminemia in patients undergoing cardiac surgery: a meta-analysis

The preoperative serum albumin level has been shown to be associated with adverse postoperative complications, meaning that hypoalbuminemia may also be a risk factor. We performed a meta-analysis to evaluate the association of serum albumin levels with survival and complication rates after cardiac surgery. Relevant articles were identified through seven databases. Twenty studies with 22553 patients (hypoalbuminemia group, n = 9903; normal group, n = 12650) who underwent cardiac surgery met the inclusion criteria after screening. The primary outcomes were that hypoalbuminemia was significantly correlated with serious long-term all-cause mortality (hazard ratio [HR]: 1.95 [1.54-2.48]; P < 0.00001) and increased mortality (risk ratio [RR] = 1.91 [1.61-2.27], P < 0.00001). Hypoalbuminemic patients with cardiopathy were more likely to suffer postoperative complications (bleeding, infections, renal injury, and others) than those whose serum albumin levels were normal. Furthermore, hypoalbuminemia increased the time in the intensive-care unit (ICU) (mean difference [MD] = 1.18 [0.49-1.87], P = 0.0008), length of hospital stay (LOS) (MD = 3.34, 95% CI: 1.88-4.80, P < 0.00001), and cardiopulmonary bypass time (CPB) (MD = 12.40 [1.13-23.66], P = 0.03). Hypoalbuminemia in patients undergoing cardiac surgery appears to have a poor all-cause mortality or increased risk of complications. Adjusted perioperative serum albumin levels and treatment strategies for this high-risk population have the potential to improve the survival.

Complications in post-bariatric body contouring surgery using a practical treatment regime to optimise the nutritional state

Background

Post-bariatric body contouring surgery (BCS) treats redundant skin after massive weight loss; however, the complication risk is relatively high (23-70%). Most complications are wound-related, which may be partly due to a poor nutritional status after bariatric surgery. The objective of this observational study was to optimise nutrition preoperatively and assess the prevalence of wound-related complications after BCS.

Methods

This prospective cohort study included 140 patients. Patients were treated according to the post-bariatric BCS guideline. Nutritional parameters were collected via pre- and peri-operative blood sampling; any deficiencies were treated. A protein-enriched diet was prescribed by a dietician 4 weeks preoperatively up until closure of all wounds. Complications were recorded using the Clavien-Dindo classification. Univariate and multivariate regression analyses were performed to identify variables associated with wound-related complications.

Results

The overall wound-related complication rate was 51%. Most complications were minor, with only 4.3% was considered major. No significant differences in patient characteristics were found between patients with and without complications. Variables indicating an optimised nutritional state were not significantly associated with a decreased risk of complications; the most influential factor was a sufficient post-operative protein intake (OR 0.27, 95% CI 0.07 – 1.02, p = 0.05).

Conclusion

The overall wound-related complication rate was in accordance with previous literature; however, major complications were few. This study showed a weak correlation between optimising nutritional state and better outcome after BCS, especially following a protein-enriched diet post-operatively. Therefore, we recommend continuing research on nutrition and wound-related complications, using homogeneous study populations and well-defined complications.

Predictive Value of Preoperative High-Sensitive C-reactive Protein (hs-CRP)/Albumin Ratio in Systemic Inflammatory Response Syndrome (SIRS) After Semi-rigid Ureteroscopy

Objective: To determine the predictive value of high-sensitive C-reactive protein (hs-CRP)/albumin ratio in systemic inflammatory response syndrome (SIRS) after semi-rigid ureteroscopy (URS).

Material and Methods: Between April 2021 and October 2021, 148 patients who had ureteral stone treatment with a ureteroscope in our hospital were included. Preoperative hs-CRP/albumin ratio was obtained by dividing the hs-CRP level by the albumin level. High-sensitivity modified Glasgow prognostic score (hs-mGPS) was obtained according to hs-CRP and albumin values. Two groups were identified as post-URS SIRS positive and negative. Inflammation biomarkers were evaluated in groups.

Results: There was a statistically significant difference between groups in terms of preoperative hs-CRP, albumin, and hs-CRP/albumin ratio (p < 0.001, p = 0.003, and p < 0.001, respectively). The optimal cutoff value for the hs-CRP/albumin ratio was 0.04651. While the risk of developing SIRS after surgery was 72.73% in patients with a hs-CRP/albumin ratio higher than 0.04651, the chance of not developing SIRS was 87.5% in patients below this value. The probability of developing SIRS was found to be significantly different in hs-mGPS (p < 0.001).

Conclusion: Our study indicated that hs-CRP/albumin ratio can predict post-URS SIRS. Larger-scale, multicentric prospective studies should certainly be done to validate the predictive value of hs-CRP/albumin ratio in post-URS SIRS.

Preoperative serum albumin: a promising indicator of early mortality after surgery for infective endocarditis

Background

Despite novel improvements in the diagnosis and treatment of infective endocarditis (IE), there has been no significant improvement in the survival rate of IE, which indicates that many details still need to be optimized in the preoperative assessment. We sought to evaluate preoperative serum albumin as a biomarker for predicting early mortality after IE surgery.

Methods

Between October 2013 and June 2019, patients with a definite diagnosis of IE were enrolled in this study. Patients’ albumin levels at admission were used as the preoperative albumin levels. Restricted cubic spline and multivariate logistic regression analyses were performed to evaluate the relationship between albumin and early mortality. Receiver operating characteristic curve analyses were performed to assess the role of albumin in predicting early mortality and compare the predictive capacity of traditional models with models that included albumin.

Results

Of the 276 IE patients, 20 (7.2%) died in hospital or within 30 days of surgery. Hypoalbuminemia (an albumin level <3.5 g/dL) was present in 109 (39.5%) patients. The multivariate logistic regression analysis showed that preoperative albumin was inversely associated with early mortality [adjusted odds ratio (OR) =0.22 per 1 g/dL, 95% confidence interval (CI): 0.07–0.65, P=0.006] after full adjustment. Preoperative albumin had value in predicting early mortality [area under the curve (AUC) =0.72, 95% CI: 0.61–0.84; P<0.01]. After adding albumin to the European System for Cardiac Operative Risk Evaluation (EuroSCORE) and Charlson score, the predictive ability of the model was further improved (EuroSCORE II: AUC =0.55; 95% CI: 0.42–0.67 to AUC =0.72; 95% CI: 0.61–0.84; Charlson score: AUC =0.73; 95% CI: 0.64–0.83 to AUC =0.78; 95% CI: 0.68–0.88).

Conclusions

Preoperative serum albumin is inversely associated with early mortality after IE surgery, and is a promising prognostic indicator in preoperative risk stratification assessments of IE patients.

Nutritional assessment and the role of preexisting inflammation with a bearing on COVID-19

 Although there is consensus in the European, American, Latin-American, and Asiatic nutrition and metabolic scientific societies regarding the definition of malnutrition, this definition has not been operationalized. This means that in different countries, the risk of malnutrition on outcome cannot be adequately determined or predicted. In patients with inflammatory activity, the preexistent nutritional status is an important predictor of outcome. Malnutrition is characterized by three crucial elements: undernutrition, inflammation, and diminished function. Malnutrition in our countries as well as in countries with famine almost always is caused by varying degrees of deficient nutritional intake in combination with disease or other damaging inflammatory causes of varying severity. The female genome appears to be better equipped to survive intercurrent trauma or illness than the male one, which impacts on longevity and the ability to overcome certain infections like COVID-19 at higher ages.

Survival and Nutritional Status of Male and Female Heart Transplant Patients Based on the Nutritional Risk Index

Malnutrition among heart-transplant patients may affect survival. The aim was to investigate the survival and nutrition status among male and female heart transplant patients who underwent transplantation, before and 1 year after surgery based on the nutritional risk index (NRI). The medical records of ninety heart-transplant patients (2009–2014) from the King Faisal Specialist Hospital, Riyadh, were reviewed. The assessment included demographic data, anthropometric measurements, and NRI calculation. Moreover, postoperative data included the length of stay and survival. Paired t-test and survival analysis by Kaplan–Meier (KM) curves were used. A total of 90 patients (males 77.78%) were included. The prevalence of malnutrition in the preoperative phase by NRI was 60% (7.78% as severe; 40% as moderate, and 12.22% mild NRI scores). After 1 year, body mass index (BMI) and NRI increased significantly (p < 0.001). Furthermore, NRI was significantly different between men and women (p < 0.01), while KM survival curves were insignificantly different (p = 0.67). Recipients with postoperative moderate or severe nutritional risk (NRI < 97.5) had significantly shorter survival in the first-year post-transplantation (HR = 0.82; 95% CI, 0.75–0.89; p < 0.001). Our findings indicate that the NRI after 1 year of transplant correlated significantly with mortality. Besides, there was no significant gender difference regarding survival; however, malnutrition and low survival were more prominent among women.

Hypoalbuminemia Increased the Length of Stay in the Treatment of Postoperative Acute Surgical Site Infection in Spinal Surgery

STUDY DESIGN

Multicenter retrospective study.

OBJECTIVE

The aim of this study was to identify specific risk factors for increased length of stay (LOS) in the management of acute surgical site infection (SSI) following spinal surgery.

SUMMARY OF BACKGROUND DATA

Postoperative SSI is a serious complication of spinal surgery and is known to be associated with increased LOS and additional cost. Although many risk factors contribute to the development of SSI following spinal surgery, little is known about risk factors associated with the treatment of SSI that contribute to increased LOS.

METHODS

Patients at two institutions experiencing deep SSI following spinal surgery between January 2009 and December 2016 were identified. The patients were divided into two groups depending upon the median LOS attributable to SSI. The effects of patient characteristics, comorbidities, disease history, and invasiveness of the elective surgery on the risk of increased LOS were determined using univariate analyses and multivariate logistic regression.

RESULTS

Of the 1656 spinal surgery cases, 40 (2.4%) experienced deep SSI. The median LOS was 67 days. Multivariate logistic regression analysis revealed that hypoalbuminemia during hospitalization was associated with increased LOS (odds ratio 0.042, confidence interval 0.005-0.342; P = 0.003). We determined the appropriate diagnostic cutoff of hypoalbuminemia during hospitalization using receiver-operating characteristic curves. A serum albumin level <3.1 g/dL (sensitivity, 86.4%; specificity, 75.0%; area under the curve, 0.84) was indicative of a longer hospital stay.

CONCLUSION

Low serum albumin level during hospitalization was an independent risk factor for increased LOS in the treatment of SSI following spinal surgery. When the serum albumin level is <3.1 g/dL in patients with SSI, we should consider interventions aimed at correcting this hypoalbuminemia.

LEVEL OF EVIDENCE

4.

Albumin-globulin ratio: a novel predictor of sepsis after flexible ureteroscopy in patients with solitary proximal ureteral stones

Background

To identify predictors of sepsis after flexible ureteroscopy (fURS) in patients with unilateral, solitary, proximal ureteral stones and evaluate the association between albumin-globulin ratio (AGR) and sepsis.

Methods

Overall, 759 patients who underwent fURS were retrospectively enrolled. Univariate and multivariate logistic regression analyses were performed to identify predictors of sepsis after fURS in patients with solitary proximal ureteral stones. Then A nomogram was generated using the predictors.

Results

Sepsis occurred in 43 patients (5.7%), and 6 (0.8%) of them developed septic shock. Univariate analysis showed that age, female sex, albumin concentration, globulin concentration, AGR, pre-operative fever, white blood cell (WBC) count, urine culture (UC) result, urine WBC count, and urine nitrite result were predictors of sepsis. Multivariate analysis identified AGR <1.2 [odds ratio (OR) =2.810, 95% confidence interval (CI): 1.245-6.342, P=0.013] and positive UC (OR =10.520, 95% CI: 4.489-24.653, P<0.001) as independent predictors. When AGR <1.2 and positive UC were combined, area under the receiver operator characteristic curve was 0.825. Then patients were categorized by different AGR level ("≥1.4", "1.2-1.4", "1.0-1.2", "<1.0"), and corresponding sepsis rates were 27.7%, 9.8%, 4.5% and 2.5%.

Conclusions

Positive UC and low AGR were independent predictors of post-fURS sepsis. Cautious pre-operative evaluation and optimized treatment strategy should be considered to minimize infectious complications.

The influence of postoperative albumin levels on the outcome of cardiac surgery

BACKGROUND

The prognostic role of low postoperative serum albumin levels (SAL) after cardiac surgery (CS) remains unclear in patients with normal preoperative SAL. Our aim was to evaluate the influence of SAL on the outcome of CS.

METHODS

Prospective observational study. Patients undergoing CS with normal preoperative SAL and nutritional status were included and classified into different subgroups based on SAL at 24 h after CS. We assessed outcomes (i.e., in-hospital mortality, postoperative complications and long-term survival) and results were analyzed among the different subgroups of SAL.

RESULTS

We included 2818 patients. Mean age was 64.5 ± 11.6 years and body mass index 28.0 ± 4.3Kg·m^- 2. 5.8%(n = 162) of the patients had normal SAL levels(≥35 g·L^- 1), 32.8%(n = 924) low deficit (30-34.9 g·L^- 1), 44.3%(n = 1249) moderate deficit (25-29.9 g·L^- 1), and 17.1%(n = 483) severe deficit(< 25 g·L^- 1). Higher SAL after CS was associated with reduced in-hospital (OR:0.84;95% CI:0.80-0.84; P = 0.007) and long-term mortality (HR:0.85;95% CI:0.82-0.87;P < 0.001). Subgroups of patients with lower SAL showed worst long-term survival (5-year mortality:94.3% normal subgroup, 87.4% low, 83.1% moderate and 72.4% severe;P < 0.001). Multivariable analysis showed higher in-hospital mortality, sepsis, hemorrhage related complications, and ICU stay in subgroups of patients with lower SAL. Predictors of moderate and severe hypoalbuminemia were preoperative chronic kidney disease, previous CS, and longer cardiopulmonary bypass time.

CONCLUSIONS

The presence of postoperative hypoalbuminemia after CS is frequent and the degree of hypoalbuminemia may be associated with worst outcomes, even in the long-term scenario.

Association of body mass index and all-cause mortality in patients after cardiac surgery: A dose-response meta-analysis

Ample studies have reported the effect of body mass index (BMI) on the prognosis of patients undergoing cardiac surgery, but the results remain inconsistent. Therefore, we aimed to conduct a dose-response meta-analysis to clarify the relationship between BMI and all-cause mortality in this population. A systematic search was performed in the PubMed and Embase databases through April 2019 for studies that reported the impact of BMI on all-cause mortality in patients after cardiac surgery. Pooled risk ratios (RRs) were calculated using a random-effects model. Non-linear associations were explored with restricted cubic spline models. Forty-one studies with a total of 54,300 cases/1,774,387 patients were included. The pooled RR for all-cause mortality was 0.93 (95% CI 0.89-0.97) for every 5-unit increment in BMI, indicating that higher BMI did not increase the risk of all-cause mortality in patients after cardiac surgery. A U-shaped association with the nadir of risk at a BMI of 25-27.5 kg/m² was observed, as well as a higher mortality risk for the underweight and the extremely obese patients. The subgroup analysis revealed that this phenomenon remained regardless of mean age, surgery type, geographic location and number of cases. Overall, for patients after cardiac surgery, a slightly higher BMI may be instrumental in survival, whereas underweight and extreme obesity is associated with a worse prognosis.

Construction of a comprehensive nutritional index and its correlation with quality of life and survival in patients with nasopharyngeal carcinoma undergoing IMRT: A prospective study

OBJECTIVES

The aim of this study was to investigate the relationship between a comprehensive nutritional index (CNI) and QoL in patients with NPC who undergo IMRT and to explore the relationship between CNI and survival.

METHODS

359 patients with newly diagnosed NPC were enrolled. QoL was assessed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 and Quality of Life Questionnaire Head and Neck Cancer Module at three time points: before, immediately after, and 3 months after IMRT. The CNI comprised five values including body mass index, usual body weight percentage, hemoglobin, albumin, and total lymphocyte count, and was evaluated before and immediately after IMRT. The correlation between the CNI and QoL and the effect of CNI on prognosis were analysed.

RESULTS

QoL and CNI scores decreased remarkably after IMRT (P < 0.05). The CNI was quite low in patients with III-IV clinical tumor stage and those undergoing induction chemotherapy plus concurrent chemotherapy. After IMRT, lower CNI score correlated worse QoL (P < 0.05). The Kaplan-Meier curve indicated that patients with lower CNI had significantly poorer survival outcomes (P = 0.02). In multivariate analysis, CNI remained an independent prognostic factor of overall survival (P = 0.046).

CONCLUSIONS

CNI can be recommended as an appropriate indicator reflecting the integrated nutrition status of NPC patients. Low CNI was associated with poor QoL and predicted a poor survival outcome. More interventions should be taken to improve the nutrition status of NPC patients to improve QoL and enhance survival outcomes.

Predictors of Increased Length of Hospital Stay in Patients with Severe Cardiomyopathy Undergoing Coronary Artery Bypass Grafting

OBJECTIVE

Predictors of operative outcome in patients with severely depressed left ventricular ejection fraction (LVEF) undergoing coronary artery bypass grafting (CABG) remain poorly defined. This study aims to identify preoperative variables that are associated with increased postoperative length of hospital stay or operative mortality in this patient population.

DESIGN

Retrospective study.

SETTING

Single tertiary care university hospital.

PARTICIPANTS

Patients undergoing isolated CABG between January 2012 and March 2017 with an LVEF ≤ 25%.

INTERVENTIONS

Isolated CABG.

MEASUREMENTS AND MAIN RESULTS

Primary endpoint was a composite of prolonged length of stay, defined as postoperative length of stay >7 days or operative mortality. Of the 201 patients, 99 (49.3%) met the primary endpoint. Patient comorbidities, clinical presentation, presence of Q-waves on electrocardiogram, and echocardiographic parameters including ventricular dimensions and right heart dysfunction were not associated with the primary endpoint. On multivariable analysis, patients who were not on preoperative beta-blockers, patients with preoperative albumin of <3.5 g/dL, and higher Society of Thoracic Surgeons Predicted Risk of Mortality score were associated with increased prolonged length of stay or death.

CONCLUSIONS

More than half of patients with severely depressed LVEF undergoing isolated CABG are able to be discharged within 7 days postoperatively. The absence of preoperative beta-blockers, low preoperative albumin levels, and higher Society of Thoracic Surgeons Predicted Risk of Mortality score are associated with more complicated or slower postoperative recovery after CABG in this patient population.

Does body mass index truly affect mortality and cardiovascular outcomes in patients after coronary revascularization with percutaneous coronary intervention or coronary artery bypass graft? A systematic review and network meta-analysis

BACKGROUND

Obesity, a comorbid medical condition, is usually observed in patients with established coronary artery disease. Paradoxically, patients with a higher body mass index (BMI) usually have better clinical outcomes after coronary revascularization.

METHODS

We searched five online databases through December 2017. We identified studies reporting the rate of all-cause mortality or cardiovascular-related outcomes among patients after coronary revascularization with percutaneous coronary intervention or coronary artery bypass graft based on various BMI categories. Network meta-analysis was performed using Bayesian methods.

RESULTS

Sixty-five records involving 865,774 participants were included in our study. A U-shaped association was observed across BMI categories for all-cause mortality. Using normal weight as the reference, all-cause mortality was increased for (relative risk [RR]: 2.4; 95% credibility interval [CrI]: 2.1-2.7) patients with underweight, whereas it was lowered in patients with overweight, obese, and severely obese. This association remained significant in many subgroups. We also observed that the risk of major adverse cardiovascular events (MACE) was lowest among patients with overweight. Furthermore, patients with underweight were associated with greater risks of myocardial infarction (RR: 1.9; 95% CrI: 1.4-2.5), cardiovascular-related mortality (RR: 2.8; 95% CrI: 1.6-4.7), stroke (RR: 2.0; 95% CrI: 1.3-3.3) and heart failure (RR: 1.7; 95% CrI: 1.1-2.7) compared with normal weight patients; no significant association was observed among individuals with higher BMI.

CONCLUSIONS

The 'obesity paradox' does exist in patients after coronary revascularization, especially for patients with post-percutaneous coronary intervention. All-cause mortality in patients with high BMI is significantly lower compared with patients with normal weight. Furthermore, patients with underweight experience higher rates of cardiovascular outcomes compared with patients with normal weight.

Association of Frailty and Long-Term Survival in Patients Undergoing Coronary Artery Bypass Grafting

BACKGROUND

Frailty is increasing in prevalence and poses a formidable challenge for clinicians. The cardiac surgery literature consists primarily of small single-center studies with limited follow-up, and the epidemiological features of frailty remain to be elucidated in long-term follow-up.

METHODS AND RESULTS

We conducted a population-based, retrospective, cohort study in Ontario, Canada, between 2008 and 2015. Frailty was defined using the Johns Hopkins Adjusted Clinical Groups frailty indicator (a multidimensional instrument validated for research using administrative data). The primary outcome was mortality. Mortality rates were calculated using the Kaplan-Meier method. The hazard of death was assessed using a multivariable Cox proportional hazard model. Of 40 083 patients, 8803 (22%) were frail. At 4±2 years of follow-up, age- and sex-standardized mortality rate per 1000 person-years was higher in frail (33; 95% confidence interval, 29-36) compared with nonfrail (22; 95% confidence interval, 19-24) patients. Frailty was associated with an increased risk of long-term mortality (adjusted hazard ratio, 1.20; 95% confidence interval, 1.12-1.28) and greater differences in the survival of patients between 40 and 74 years of age than in those who were ≥85 years old.

CONCLUSIONS

Frailty was present in a large proportion of patients undergoing coronary artery bypass grafting and was independently associated with long-term mortality. The adjusted risk of frailty-related death was inversely proportional to age. Our findings highlight the need for more comprehensive preoperative risk stratification models to assist with optimal selection of operative candidates. In addition, we identified the <75 years age group as a potential target for comprehensive preoperative optimization programs, such as cardiac prehabilitation, nutritional augmentation, and psychosocial support.

Value of Preoperative Modified Body Mass Index in Predicting Postoperative 1-Year Mortality

Serum albumin and conventional BMI (cBMI) are commonly used indices of malnutrition status. Because cBMI does not reflect fluid accumulation, modified body mass index (mBMI, serum albumin × cBMI) is a more accurate measure of malnutrition status. This study investigated the association between preoperative mBMI and postoperative 1-year mortality, in comparison with serum albumin and cBMI. Medical records of 80,969 adult patients who underwent surgical procedures in a tertiary care hospital between 1 January, 2011 and 31 December, 2015 were retrospectively reviewed. Postoperative 1-year mortality increased with reduction in cBMI, mBMI, and albumin separately (P < 0.001). When considering interaction between cBMI and albumin, albumin was the only significant factor of postoperative 1-year mortality [odds ratio: 0.377, 95% confidence interval (0.245–0.579), P < 0.001], while cBMI or interaction (cBMI * albumin) was not significant (P > 0.05). Adjusted area under the curve (AUC) was highest (0.885) in the overall model (cBMI + albumin + cBMI * albumin); adjusted AUC between mBMI and albumin did not differ significantly (P = 0.558). Low albumin is the strongest independent predictor of postoperative 1-year mortality among the three variables (albumin, cBMI, mBMI). Adding cBMI to albumin does not increase the validity of the AUC of albumin.

Association of preoperative hypoalbuminemia with postoperative acute kidney injury in patients undergoing brain tumor surgery: a retrospective study

OBJECTIVE Hypoalbuminemia is known to be independently associated with postoperative acute kidney injury (AKI). However, little is known about the association between the preoperative serum albumin level and postoperative AKI in patients undergoing brain tumor surgery. The authors investigated the incidence of AKI, impact of preoperative serum albumin level on postoperative AKI, and death in patients undergoing brain tumor surgery. METHODS The authors retrospectively reviewed the electronic medical records and laboratory results of 2363 patients who underwent brain tumor surgery between January 2008 and December 2014. Postoperative AKI was defined according to Kidney Disease: Improving Global Outcomes Definition and Staging (KDIGO). Multivariate logistic regression analysis was used to identify demographic, preoperative laboratory, and intraoperative factors associated with AKI development. Cox proportional hazards models were used to investigate the adjusted odds ratio and hazard ratio for the association between preoperative serum albumin level and outcome variables. RESULTS The incidence of AKI was 1.8% (n = 43) using KDIGO criteria. The incidence of AKI was higher in patients with a preoperative serum albumin level < 3.8 g/dl (3.5%) than in those with a preoperative serum albumin level ≥ 3.8 g/dl (1.2%, p < 0.001). The overall mortality was also higher in the former than in the latter group (5.0% vs 1.8%, p < 0.001). After inverse probability of treatment-weighting adjustment, a preoperative serum albumin level < 3.8 g/dl was also found to be associated with postoperative AKI (OR 1.981, 95% CI 1.022-3.841; p = 0.043) and death (HR 2.726, 95% CI 1.522-4.880; p = 0.001). CONCLUSIONS The authors' results demonstrated that a preoperative serum albumin level of < 3.8 g/dl was independently associated with AKI and mortality in patients undergoing brain tumor surgery.

Body Mass Index and Mortality Among Adults Undergoing Cardiac Surgery: A Nationwide Study With a Systematic Review and Meta-Analysis

BACKGROUND

In an apparent paradox, morbidity and mortality are lower in obese patients undergoing cardiac surgery, although the nature of this association is unclear. We sought to determine whether the obesity paradox observed in cardiac surgery is attributable to reverse epidemiology, bias, or confounding.

METHODS

Data from the National Adult Cardiac Surgery registry for all cardiac surgical procedures performed between April 2002 and March 2013 were extracted. A parallel systematic review and meta-analysis (MEDLINE, Embase, SCOPUS, Cochrane Library) through June 2015 were also accomplished. Exposure of interest was body mass index categorized into 6 groups according to the World Health Organization classification.

RESULTS

A total of 401 227 adult patients in the cohort study and 557 720 patients in the systematic review were included. A U-shaped association between mortality and body mass index classes was observed in both studies, with lower mortality in overweight (adjusted odds ratio, 0.79; 95% confidence interval, 0.76-0.83) and obese class I and II (odds ratio, 0.81; 95% confidence interval, 0.76-0.86; and odds ratio, 0.83; 95% confidence interval, 0.74-0.94) patients relative to normal-weight patients and increased mortality in underweight individuals (odds ratio, 1.51; 95% confidence interval, 1.41-1.62). In the cohort study, a U-shaped relationship was observed for stroke and low cardiac output syndrome but not for renal replacement therapy or deep sternal wound infection. Counter to the reverse epidemiology hypotheses, the protective effects of obesity were less in patients with severe chronic renal, lung, or cardiac disease and greater in older patients and in those with complications of obesity, including the metabolic syndrome and atherosclerosis. Adjustments for important confounders did not alter our results.

CONCLUSIONS

Obesity is associated with lower risks after cardiac surgery, with consistent effects noted in multiple analyses attempting to address residual confounding and reverse causation.

Relationship Between the Comprehensive Nutritional Index and the EORTC QLQ-H&N35 in Nasopharyngeal Carcinoma Patients Treated with Intensity-Modulated Radiation Therapy

This study aimed to explore the relationship between the comprehensive nutritional index (CNI) and quality of life in nasopharyngeal carcinoma (NPC) patients receiving intensity-modulated radiation therapy (IMRT). The nutritional index, which includes total lymphocyte count, hemoglobin and albumin levels, body mass index, and usual body weight percentage, was evaluated pre-treatment and post-treatment in patients who underwent IMRT. The quality of life of NPC patients was measured by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Head and Neck Cancer Module (EORTC QLQ-H&N35) at four time points: pre-treatment, post-treatment, and 3 and 6 mo after IMRT. A comprehensive nutritional model was used to assess the correlation with QLQ-H&N35. The nutritional index decreased significantly post-treatment. The CNI was associated with immunotherapy; the International Union Against Cancer (UICC) stage; concurrent chemotherapy; speech problems, trouble with social contact, feeling ill and having dental problems at pre-treatment; sexuality at 3 mos post-treatment; and sensory problems and xerostomia at 6 mo post-treatment (P < 0.05). The nutritional status and QLQ-H&N35 scores in NPC patients decreased during IMRT. Our study provides an alternative measure of the CNI to improve the QLQ-H&N35 evaluation system for patients with NPC.

Preoperative Frailty Assessment and Outcomes at 6 Months or Later in Older Adults Undergoing Cardiac Surgical Procedures: A Systematic Review

BACKGROUND

Frailty assessment may inform surgical risk and prognosis not captured by conventional surgical risk scores.

PURPOSE

To evaluate the evidence for various frailty instruments used to predict mortality, functional status, or major adverse cardiovascular and cerebrovascular events (MACCEs) in older adults undergoing cardiac surgical procedures.

DATA SOURCES

MEDLINE and EMBASE (without language restrictions), from their inception to 2 May 2016.

STUDY SELECTION

Cohort studies evaluating the association between frailty and mortality or functional status at 6 months or later in patients aged 60 years or older undergoing major or minimally invasive cardiac surgical procedures.

DATA EXTRACTION

2 reviewers independently extracted study data and assessed study quality.

DATA SYNTHESIS

Mobility, disability, and nutrition were frequently assessed domains of frailty in both types of procedures. In patients undergoing major procedures (n = 18 388; 8 studies), 9 frailty instruments were evaluated. There was moderate-quality evidence to assess mobility or disability and very-low- to low-quality evidence for using a multicomponent instrument to predict mortality or MACCEs. No studies examined functional status. In patients undergoing minimally invasive procedures (n = 5177; 17 studies), 13 frailty instruments were evaluated. There was moderate- to high-quality evidence for assessing mobility to predict mortality or functional status. Several multicomponent instruments predicted mortality, functional status, or MACCEs, but the quality of evidence was low to moderate. Multicomponent instruments that measure different frailty domains seemed to outperform single-component ones.

LIMITATION

Heterogeneity of frailty assessment, limited generalizability of multicomponent frailty instruments, few validated frailty instruments, and potential publication bias.

CONCLUSION

Frailty status, assessed by mobility, disability, and nutritional status, may predict mortality at 6 months or later after major cardiac surgical procedures and functional decline after minimally invasive cardiac surgery.

PRIMARY FUNDING SOURCE

National Institute on Aging and National Heart, Lung, and Blood Institute.

Effect of Preoperative Albumin Levels on Outcomes in Patients Undergoing Left Ventricular Device Implantation

Hypoalbuminemia is a well-known predictor of morbidity and mortality in cardiac surgery. Our aim was to establish the impact of serum albumin on outcomes after left ventricular assist device (LVAD) implantation. This was a single-institution retrospective review, including all patients who underwent LVAD implantation between March 2006 and June 2014. Two hundred patients were included in the analysis. Mean serum albumin was 3.27 ± 0.47 g/dl, with 7% in the low albumin group (<2.5 mg/dl), 67.5% in the mid-range (2.5-3.5 mg/dl), and 25.5% in the normal albumin groups (> 3.5 mg/dl). Lower albumin was associated with a significant increase in postoperative renal failure (42.9 vs. 16.5 vs. 17.3%; p = 0.05) and prolonged hospitalization (median 28.5 vs. 16 vs. 15.5 days; p = 0.008). Six month, 1 year, and 5 year survival was 79%, 79%, and 49% with low, 84%, 78%, and 51% with mid-range, and 94%, 88%, and 60% with normal albumin, respectively (p = 0.22). Preoperative hypoalbuminemia is associated with postoperative acute renal failure (ARF) and prolonged hospitalization after LVAD implantation, with no effect on overall survival. Hypoalbuminemia is most likely a marker of advanced disease and should not, in itself, be considered a contraindication to LVAD candidacy.

Is low serum albumin associated with postoperative complications in patients undergoing cardiac surgery?

A best evidence topic was written according to a structured protocol. The clinical question investigated was: is low serum albumin associated with postoperative complications in patients undergoing cardiac surgery? There were 62 papers retrieved using the reported search strategy. Of these, 12 publications embodied the best evidence to answer this clinical question. The authors, journal, date and country of the publication, patient group investigated, study design, relevant outcomes and results of these papers were tabulated. This paper includes a total of 12 589 patients, and of the papers reviewed, 4 were level 3 and 8 level 4. Each of the publications reviewed and compared either all or some of the following postoperative complications: mortality, postoperative bleeding requiring reoperation, prolonged hospital stay and ventilatory support, infection, liver dysfunction, delirium and acute kidney injury (AKI). Of the studies that examined postoperative mortality, all except for three established a significant multivariate association with low preoperative albumin level. Some scepticism is required in accepting other results that were only present in univariate analysis. While three studies examined multiple levels of serum albumin, most dichotomized the serum albumin levels into normal and abnormal groups. This led to differing classifications of hypoalbuminaemia, ranging from less than 2.5 to 4.0 g/dl. The available evidence, however, suggests that low preoperative serum albumin level in patients undergoing cardiac surgery is associated with the following: (i) increased risk of mortality after surgery and (ii) greater incidence of postoperative morbidity. While the evidence supports the use of preoperative albumin in assessing post-cardiac surgery complications, a specific level of albumin considered to be abnormal cannot be concluded from this review.

The influence of body mass index on outcomes in patients undergoing cardiac surgery: does the obesity paradox really exist?

Purpose

Obesity influences risk stratification in cardiac surgery in everyday practice. However, some studies have reported better outcomes in patients with a high body mass index (BMI): this is known as the obesity paradox. The aim of this study was to quantify the effect of diverse degrees of high BMI on clinical outcomes after cardiac surgery, and to assess the existence of an obesity paradox in our patients.

Methods

A total of 2,499 consecutive patients requiring all types of cardiac surgery with cardiopulmonary bypass between January 2004 and February 2009 were prospectively studied at our institution. Patients were divided into four groups based on BMI: normal weight (18.5–24.9 kg∙m⁻²; n = 523; 21.4%), overweight (25–29.9kg∙m⁻²; n = 1150; 47%), obese (≥30–≤34.9kg∙m⁻²; n = 624; 25.5%) and morbidly obese (≥35kg∙m⁻²; n = 152; 6.2%). Follow-up was performed in 2,379 patients during the first year.

Results

After adjusting for confounding factors, patients with higher BMI presented worse oxygenation and better nutritional status, reflected by lower PaO₂/FiO₂ at 24h and higher albumin levels 48h after admission respectively. Obese patients showed a higher risk for Perioperative Myocardial Infarction (OR: 1.768; 95% CI: 1.035–3.022; p = 0.037) and septicaemia (OR: 1.489; 95% CI: 1.282–1.997; p = 0.005). In-hospital mortality was 4.8% (n = 118) and 1-year mortality was 10.1% (n = 252). No differences were found regarding in-hospital mortality between BMI groups. The overweight group showed better 1-year survival than normal weight patients (91.2% vs. 87.6%; Log Rank: p = 0.029. HR: 1.496; 95% CI: 1.062–2.108; p = 0.021).

Conclusions

In our population, obesity increases Perioperative Myocardial Infarction and septicaemia after cardiac surgery, but does not influence in-hospital mortality. Although we found better 1-year survival in overweight patients, our results do not support any protective effect of obesity in patients undergoing cardiac surgery.

Infection control in the intensive care unit

It is critical for health care personnel to recognize and appreciate the detrimental impact of intensive care unit (ICU)-acquired infections. The economic, clinical, and social expenses to patients and hospitals are overwhelming. To limit the incidence of ICU-acquired infections, aggressive infection control measures must be implemented and enforced. Researchers and national committees have developed and continue to develop evidence-based guidelines to control ICU infections. A multifaceted approach, including infection prevention committees, antimicrobial stewardship programs, daily reassessments-intervention bundles, identifying and minimizing risk factors, and continuing staff education programs, is essential. Infection control in the ICU is an evolving area of critical care research.

Relationship of body mass index with total mortality, cardiovascular mortality, and myocardial infarction after coronary revascularization: evidence from a meta-analysis

OBJECTIVE

To investigate the relationship of body mass index (BMI) with total mortality, cardiovascular (CV) mortality, and myocardial infarction (MI) after coronary revascularization procedures (coronary artery bypass grafting [CABG] and percutaneous coronary intervention [PCI]).

PATIENTS AND METHODS

Systematic search of studies was conducted using PubMed, CINAHL, Cochran CENTRAL, Scopus, and the Web of Science databases. We identified studies reporting the rate of MI, CV mortality, and total mortality among coronary artery disease patients' postcoronary revascularization procedures in various BMI categories: less than 20 (underweight), 20-24.9 (normal reference), 25-29.9 (overweight), 30-34.9 (obese), and 35 or more (severely obese). Event rates were compared using a random effects model assuming interstudy heterogeneity.

RESULTS

A total of 36 studies (12 CABG; 26 PCI) were selected for final analyses. The risk of total mortality (relative risk [RR], 2.59; 95% CI, 2.09-3.21), CV mortality (RR, 2.67; 95% CI, 1.63-4.39), and MI (RR, 1.79; 95% CI, 1.28-2.50) was highest among patients with low BMI at the end of a mean follow-up period of 1.7 years. The risk of CV mortality was lowest among overweight patients (RR, 0.81; 95% CI, 0.68-0.95). Increasing degree of adiposity as assessed by BMI had a neutral effect on the risk of MI for overweight (RR, 0.92; 95% CI, 0.84-1.01), obese (RR, 0.99; 95% CI, 0.85-1.15), and severely obese (RR, 0.93; 95% CI, 0.78-1.11) patients.

CONCLUSION

After coronary artery disease revascularization procedures (PCI and CABG), the risk of total mortality, CV mortality, and MI was highest among underweight patients as defined by low BMI and CV mortality was lowest among overweight patients.

Body Mass Index or Serum Albumin Levels: Which is further Prognostic following Cardiac Surgery?

Introduction: Patients with low serum albumin and abnormal BMI may be at the risk of death and other complications after surgery. This could be remarkable in patients with coronary arteries bypass graft surgery. Therefore, we decided to evaluate the impact of these factors associated with survival and outcome after cardiac surgery.

Methods: A cross-sectional study was performed from 2009 until 2012 on 345 patients who underwent coronary artery bypass grafts. Also Patients were monitored for a year. Patients’ information was collected and then the patients were analyzed for body mass index (BMI) and serum albumin and their effects on postoperative outcomes. P value <0.05 was considered statistically significant.

Results: Mortality after CABG operation was not of a significant relation in patients with low BMI (BMI <20), normal and high (BMI> 30). Obese patients are more susceptible to myocardial infarction in postoperative period (P=0.02). Pneumonia after surgery in these patients was more common than others (P= 0.023); however, low serum albumin was significantly associated with mortality following operation (P<0.001). Reoperation due to bleeding (P<0.001) and required mechanical ventilation for more than a day (P=0.019) were significantly associated with low serum albumin.

Conclusion: In conclusion, the high or low BMI alone did not increase mortality after cardiac surgery. However, postoperative morbidity in obese patients may be greater than others. Low serum albumin may increase the risk of mortality and postoperative complications as well. Therefore, it seems ameliorating serum albumin can be effective more than body mass index in improving the outcome of patients after CABG surgery.

Obesity paradox in different populations: evidence and controversies

ABSTRACT: An inverse association between BMI and mortality has been reported in patients with coronary heart disease and heart failure. This ‘obesity paradox‘ has recently been reported in other disease states, including stroke, hypertension, incident diabetes, atrial fibrillation, hemodialysis and transcatheter aortic valve replacement. Cardiorespiratory fitness influences the obesity paradox and this inverse association may be present only in individuals with low fitness levels. Intentional weight loss, exercise training and improving lean mass are important and should be advised to all patients. Recent studies have also explored the association between measures of central obesity and direct measures of body fat with mortality. This review will summarize the evidence, controversies and mechanisms associated with the puzzling obesity paradox.

Influence of acute kidney injury on short- and long-term outcomes in patients undergoing cardiac surgery: risk factors and prognostic value of a modified RIFLE classification

INTRODUCTION

The development of acute kidney injury (AKI) is associated with poor outcome. The modified RIFLE (risk, injury, failure, loss of kidney function, and end-stage renal failure) classification for AKI, which classifies patients with renal replacement therapy needs according to RIFLE failure class, improves the predictive value of AKI in patients undergoing cardiac surgery. Our aim was to assess risk factors for post-operative AKI and the impact of renal function on short- and long-term survival among all AKI subgroups using the modified RIFLE classification.

METHODS

We prospectively studied 2,940 consecutive cardiosurgical patients between January 2004 and July 2009. AKI was defined according to the modified RIFLE system. Pre-operative, operative and post-operative variables usually measured on and during admission, which included main outcomes, were recorded together with cardiac surgery scores and ICU scores. These data were evaluated for association with AKI and staging in the different RIFLE groups by means of multivariable analyses. Survival was analyzed via Kaplan-Meier and a risk-adjusted Cox proportional hazards regression model. A complete follow-up (mean 6.9 ± 4.3 years) was performed in 2,840 patients up to April 2013.

RESULTS

Of those patients studied, 14% (n = 409) were diagnosed with AKI. We identified one intra-operative (higher cardiopulmonary bypass time) and two post-operative (a longer need for vasoactive drugs and higher arterial lactate 24 hours after admission) predictors of AKI. The worst outcomes, including in-hospital mortality, were associated with the worst RIFLE class. Kaplan-Meier analysis showed survival of 74.9% in the RIFLE risk group, 42.9% in the RIFLE injury group and 22.3% in the RIFLE failure group (P <0.001). Classification at RIFLE injury (Hazard ratio (HR) = 2.347, 95% confidence interval (CI) 1.122 to 4.907, P = 0.023) and RIFLE failure (HR = 3.093, 95% CI 1.460 to 6.550, P = 0.003) were independent predictors for long-term patient mortality.

CONCLUSIONS

AKI development after cardiac surgery is associated mainly with post-operative variables, which ultimately could lead to a worst RIFLE class. Staging at the RIFLE injury and RIFLE failure class is associated with higher short- and long-term mortality in our population.

Relation of body mass index to late survival after valvular heart surgery

Limited data have suggested that an "obesity paradox" exists for mortality and cardiovascular outcomes in patients undergoing coronary artery bypass grafting. Much less is known about the role of the preoperative body mass index (BMI) in patients undergoing valve surgery. We evaluated 2,640 consecutive patients who underwent valve surgery between April 2004 and March 2011. The patients were classified by the World Health Organization standards as "underweight" (BMI 11.5 to 18.4 kg/m(2), n = 61), "normal weight" (BMI 18.5 to 24.9 kg/m(2), n = 865), "overweight" (BMI 25 to 29.9 kg/m(2), n = 1,020), and "obese" (BMI 30 to 60.5 kg/m(2), n = 694). Mortality was ascertained using the Social Security Death Index. Hazard ratios (HRs), adjusted for known preoperative risk factors, were obtained using Cox regression models. The mean follow-up was 31.9 ± 20.5 months. The long-term mortality rate was 1.21, 0.52, 0.32, and 0.44 per 10 years of person-time for underweight, normal, overweight, and obese patients, respectively. Compared to the normal BMI category, overweight patients (adjusted HR 0.60, 95% confidence interval 0.46 to 0.79, p <0.001) and obese patients (adjusted HR 0.67, 95% confidence interval 0.50 to 0.91, p = 0.009) were at a lower hazard of long-term all-cause mortality. Underweight patients remained at a greater adjusted risk of long-term mortality than normal weight patients (adjusted HR 1.69, 95% confidence interval 1.01 to 2.85, p = 0.048). Similar patterns of mortality outcomes were noted in the subset of patients undergoing isolated valve surgery. In conclusion, overweight and obese patients had greater survival after valve surgery than patients with a normal BMI. Very lean patients undergoing valve surgery are at a greater hazard for mortality and might require more rigorous preoperative candidate screening and closer postoperative monitoring.

Evaluation of nutritional screening tools for patients scheduled for cardiac surgery

OBJECTIVE

The aim of this study was to assess the prognostic value of different nutritional screening tools in patients undergoing cardiopulmonary bypass with regard to an adverse clinical course.

METHODS

This prospective cohort study analyzed 894 adult patients who underwent cardiopulmonary bypass. Patients were screened using four nutritional screening tools: Nutritional Risk Screening 2002 (NRS-2002), the Malnutrition Universal Screening Tool (MUST), the Mini-Nutritional Assessment (MNA), and the Short Nutritional Assessment Questionnaire (SNAQ). Nutritional status was assessed using the Subjective Global Assessment. In-hospital mortality, postoperative complications, length of stay in the intensive care unit, and length of hospitalization were analyzed.

RESULTS

The sensitivities of the SNAQ, MUST, and NRS-2002 to detect the malnutrition confirmed by the Subjective Global Assessment were 91.5%, 97.9%, and 38.3%, respectively, and the MNA showed a sensitivity of 81.8% for the elderly. Malnutrition detected by the SNAQ, MUST, and NRS-2002 was associated with postoperative complications (odds ratios [ORs] 1.75, 1.98, and 1.82, respectively) and a stay in the intensive care unit longer than 2 d (ORs 1.46, 1.56, and 2.8). Malnutrition as detected by the SNAQ and MUST was also associated with prolonged hospitalization (ORs 1.49 and 1.59). According to multivariate logistic regression analysis, postoperative complications were independently predicted by the European System for Cardiac Operative Risk Evaluation (OR 1.1, P < 0.0001), cardiopulmonary bypass time (OR 1.01, P < 0.0001), and malnutrition identified by the MUST (OR 1.2, P = 0.01).

CONCLUSION

The MUST independently predicts postoperative complications. The SNAQ and MUST have comparable accuracy in detecting malnutrition. Whether preoperative nutritional therapy would improve the outcome in malnourished patients needs to be studied.

Preoperative total lymphocyte count in peripheral blood as a predictor of poor outcome in adult cardiac surgery

OBJECTIVE

The aim of this study was to investigate the prognostic value of the preoperative total lymphocyte count in peripheral blood as a predictor of postoperative complications and mortality in cardiac surgery.

DESIGN

A retrospective, observational study.

SETTING

The Novosibirsk State Research Institute of Circulation Pathology (single institution).

PARTICIPANTS

All adults undergoing primary cardiopulmonary bypass in 2009.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The cohort size was 1,368 patients operated upon with cardiopulmonary bypass. Patient characteristics, hospital mortality, postoperative complications, ventilation time, intensive care unit, and hospital stay were analyzed. A preoperative total lymphocyte count <1,500 cells/μL was associated with significantly higher mortality by univariate (p < 0.0001) and multivariate (p < 0.044) analyses. A low preoperative total lymphocyte count was associated with more frequent inotropic support (p < 0.001); postoperative heart arrhythmia (p < 0.001); dialysis-dependent acute renal failure (p < 0.001); and a prolonged ventilation time (p = 0.001), intensive care unit stay (p < 0.001), and hospital stay (p = 0.007).

CONCLUSIONS

A low preoperative total lymphocyte count in peripheral blood is a useful prognostic criterion for the evaluation of a complicated postoperative period in cardiac patients operated under cardiopulmonary bypass.

Incidence and impact of cardiac cachexia in valvular surgery

Cardiac cachexia is a wasting feature of advanced heart failure, which is due to several etiologies and associated with a poor prognosis. This study assessed the incidence and impact of cardiac cachexia retrospectively in 353 patients who underwent valve surgery from June 2005 to June 2006. Using 80% of ideal body weight as a cut-off point, 46 (13%) of these patients were considered to have cardiac cachexia. Patients with cachexia were predominantly male with more underlying diseases and a lower body mass index than those without cachexia. The New York Heart Association functional class was significantly worse in patients with cachexia (class III/IV: 54.4% vs. 21.2%) and they had greater incidences of active infective endocarditis (21.7% vs. 5.2%) and tricuspid regurgitation (41.3% vs. 21.8%) compared to those with normal body weight. The cachexia group had significantly longer postoperative hospitalization and more complications (37% vs. 21.5%); perioperative mortality tended to be higher (6.5% vs. 2.3%) although not statistically significant. Cardiac cachexia remains an important problem in patients undergoing valve surgery, which indicates end-staged disease, and contributes to poor perioperative outcomes. Special care and attention are needed in this particular group of patients.

Perioperative metabolic changes in patients undergoing cardiac surgery

Perioperative metabolic changes in cardiac surgical patients are not only induced by tissue injury and extracorporeal circulation per se: the systemic inflammatory response to surgical trauma and extracorporeal circulation, perioperative hypothermia, cardiovascular and neuroendocrine responses, and drugs and blood products used to maintain cardiovascular function and anesthesia contribute to varying degrees. The pathophysiologic changes include increased oxygen consumption and energy expenditure; increased secretion of adrenocorticotrophic hormone, cortisol, epinephrine, norepinephrine, insulin, and growth hormone; and decreased total tri-iodothyronine levels. Easily measurable metabolic consequences of these changes include hyperglycemia, hyperlactatemia, increased aspartate, glutamate and free fatty acid concentrations, hypokalemia, increased production of inflammatory cytokines, and increased consumption of complement and adhesion molecules. Nutritional risk before elective cardiac surgery-defined as preoperative unintended pathologic weight loss/low amount of food intake in the preceding week or low body mass index-is related to adverse postoperative outcome. Improvements in surgical techniques, anesthesia, and perioperative management have been designed to minimize the stressful stimulus to catabolism, thereby slowing the wasting process to the point where much less nutrition is required to meet metabolic requirements. Early nutrition in cardiac surgery is safe and well tolerated.