Body mass index is associated with hospital mortality in critically ill patients: an observational cohort study. Crit Care Med. 2013;41:1878-1883. [PMID: 23685638 DOI: 10.1097/ccm.0b013e31828a2aa1]

Obesity and Mortality Risk in Critically Ill Children

BACKGROUND AND OBJECTIVES

Childhood obesity is epidemic and may be associated with PICU mortality. Using a large multicenter PICU database, we investigated the association between obesity and PICU mortality, adjusting for initial severity of illness. We further investigated whether height- and weight-based classifications of obesity compared with a weight-based classification alone alter the mortality distribution.

METHODS

This retrospective analysis used prospectively collected data from the Virtual PICU Systems database. Height, weight, age, and gender were used to calculate z score groups based on Centers for Disease Control and Prevention and World Health Organization growth curves. A random effects mixed logistic regression model was used to evaluate the association between obesity and PICU mortality, controlling for hospital, initial severity of illness, and comorbidities.

RESULTS

A total of 127,607 patients were included; the mortality rate was 2.48%. Being overweight was independently associated with increased PICU mortality after controlling for severity of illness with the Pediatric Index of Mortality 2 score and preexisting comorbidities. Mortality had a U-shaped distribution when classified according to weight-for-age or weight-for-height/BMI. When classifying patients using weight-for-age without respect to height, the nadir of the mortality curve was shifted, potentially falsely implying a benefit to mild obesity.

CONCLUSIONS

Risk-adjusted PICU mortality significantly increases as weight-for-height/BMI increases into the overweight and obese ranges. We believe that height data are necessary to correctly classify body habitus; without such information, a protective benefit from mild obesity may be incorrectly concluded.

Risk factors for and prediction of mortality in critically ill medical-surgical patients receiving heparin thromboprophylaxis

Background

Previous studies have suggested that prediction models for mortality should be adjusted for additional risk factors beyond the Acute Physiology and Chronic Health Evaluation (APACHE) score. Our objective was to identify risk factors independent of APACHE II score and construct a prediction model to improve the predictive accuracy for hospital and intensive care unit (ICU) mortality.

Methods

We used data from a multicenter randomized controlled trial (PROTECT, Prophylaxis for Thromboembolism in Critical Care Trial) to build a new prediction model for hospital and ICU mortality. Our primary outcome was all-cause 60-day hospital mortality, and the secondary outcome was all-cause 60-day ICU mortality.

Results

We included 3746 critically ill non-trauma medical–surgical patients receiving heparin thromboprophylaxis (43.3 % females) in this study. The new model predicting 60-day hospital mortality incorporated APACHE II score (main effect: hazard ratio (HR) = 0.97 for per-point increase), body mass index (BMI) (main effect: HR = 0.92 for per-point increase), medical admission versus surgical (HR = 1.67), use of inotropes or vasopressors (HR = 1.34), acetylsalicylic acid or clopidogrel (HR = 1.27) and the interaction term between APACHE II score and BMI (HR = 1.002 for per-point increase). This model had a good fit to the data and was well calibrated and internally validated. However, the discriminative ability of the prediction model was unsatisfactory (C index < 0.65). Sensitivity analyses supported the robustness of these findings. Similar results were observed in the new prediction model for 60-day ICU mortality which included APACHE II score, BMI, medical admission and invasive mechanical ventilation.

Conclusion

Compared with the APACHE II score alone, the new prediction model increases data collection, is more complex but does not substantially improve discriminative ability.

Trial registration: ClinicalTrials.gov Identifier: NCT00182143

Obesity Prevalence and Associated Outcomes in Cardiothoracic Patients: A Single-Centre Experience

The objective of this study was to investigate the prevalence of obesity and its relationship with adverse outcomes in ICU cardiothoracic patients. We performed a retrospective analysis of cardiothoracic patients admitted to The Royal Melbourne Hospital ICU between 2002 and 2014. Eight thousand and sixty-four patients who underwent coronary artery bypass, valve replacement/repair, or both, were divided into six categories of body mass index using World Health Organization criteria. Prevalence of obesity over time in the ICU was measured and compared to prevalence of obesity in the adult Australian population. The association between obesity and adverse postoperative outcomes was then analysed. Obesity is currently 1.2 times more prevalent in the Royal Melbourne Hospital ICU cardiothoracic patients than in the adult Australian population, with 33.5% of patients having a body mass index ≥30 kg/m2. Over time, this was relatively constant, but an increasing proportion were morbidly obese. Obesity, but not morbid obesity, was associated with reduced 30-day mortality (odds ratio [OR] 0.41). Both obese and morbidly obese patients had reduced odds of return to theatre for bleeding (OR 0.49 and OR 0.19, respectively), but increased odds of new-onset renal failure (OR 1.62 and OR 3.17, respectively). Morbidly obese patients had double the odds of an ICU stay longer than 14 days (OR 2.05). In summary, a growing proportion of our obese ICU patients are morbidly obese, with a dramatically increased length of ICU stay. This has major implications for resource allocation in the ICU, and may inform modelling of future bed utilisation. Obesity, but not morbid obesity, conferred a mortality benefit.

Inverse relationship between body mass index and mortality in older nursing home residents: a meta-analysis of 19,538 elderly subjects

Body mass index (BMI) and mortality in old adults from the general population have been related in a U-shaped or J-shaped curve. However, limited information is available for elderly nursing home populations, particularly about specific cause of death. A systematic PubMed/EMBASE/CINAHL/SCOPUS search until 31 May 2014 without language restrictions was conducted. As no published study reported mortality in standard BMI groups (<18.5, 18.5-24.9, 25-29.9, ≥30 kg/m(2)), the most adjusted hazard ratios (HRs) according to a pre-defined list of covariates were obtained from authors and pooled by random-effect model across each BMI category. Out of 342 hits, 20 studies including 19,538 older nursing home residents with 5,223 deaths during a median of 2 years of follow-up were meta-analysed. Compared with normal weight, all-cause mortality HRs were 1.41 (95% CI = 1.26-1.58) for underweight, 0.85 (95% CI = 0.73-0.99) for overweight and 0.74 (95% CI = 0.57-0.96) for obesity. Underweight was a risk factor for higher mortality caused by infections (HR = 1.65 [95% CI = 1.13-2.40]). RR results corroborated primary HR results, with additionally lower infection-related mortality in overweight and obese than in normal-weight individuals. Like in the general population, underweight is a risk factor for mortality in old nursing home residents. However, uniquely, not only overweight but also obesity is protective, which has relevant nutritional goal implications in this population/setting.

Nutritional support in critical illness and recovery

An adequate nutritional status is crucial for optimum function of cells and organs, and for wound healing. Options for artificial nutrition have greatly expanded in the past few decades, but have concomitantly shown limitations and potential side-effects. Few rigorous randomised controlled trials (RCTs) have investigated enteral or parenteral nutritional support, and evidence-based clinical guidance is largely restricted to the first week of critical illness. In the early stages of critical illness, whether artificial feeding is better than no feeding intervention has been given little attention in existing RCTs. Expected beneficial effects of various forms of early feeding interventions on rates of morbidity or mortality have generally not been supported by results of recent high-quality RCTs. Thus, whether nutritional interventions early in an intensive care unit (ICU) stay improve outcomes remains unclear. Trials assessing feeding interventions that continue after the first week of critical illness and into the post-ICU and post-hospital settings are clearly needed. Although acute morbidity and mortality will remain important safety parameters in such trials, primary outcomes should perhaps, in view of the adjunctive nature of nutritional intervention in critical illness, be focused on physical function and assessed months or even years after patients are discharged from the ICU. This Series paper is based on results of high-quality RCTs and provides new perspectives on nutritional support during critical illness and recovery.

Modification of the β-Adrenoceptor Stimulation Pathway in Zucker Obese and Obese Diabetic Rat Myocardium

OBJECTIVES

Although metabolic syndrome is associated with increased sympathetic activity that chronically stimulates β-adrenoceptors, the β-adrenoceptor signaling pathway has been poorly studied in this situation. We studied the β-adrenoceptor signaling pathway in Zucker lean, obese, and obese diabetic rats.

DESIGN

Experimental, prospective study.

SETTING

University medical research laboratory.

SUBJECTS

Adult male Zucker lean (control), obese, and obese diabetic rats.

INTERVENTIONS

The effects of β-adrenoceptor stimulation were investigated in vitro in isolated left ventricular papillary muscles in control, obese, and obese diabetic rats. β1-, β2-, and β3-adrenoceptors and multidrug resistance-associated protein 4 were quantified by Western Blotting. Triglyceride, cholesterol, leptin, adiponectin, and C-peptide plasma concentrations were measured. Data are mean ± SD.

MEASUREMENTS AND MAIN RESULTS

Hyperlipidemia, high leptin, and C-peptide concentrations were observed in obese and obese diabetic strains, whereas hyperglycemia occurred only in the diabetic strain. The positive inotropic effect of isoproterenol was slightly reduced in obese rats (183% ± 11% of baseline; p = 0.003; n = 7) and markedly reduced in obese diabetic rats (137% ± 18% of baseline; p < 0.001; n = 10) when compared with control rats (210% ± 17% of baseline; n = 9). β1-adrenoceptors were down-regulated in obese (-41%; p = 0.02) and diabetic (-54%; p = 0.003) when compared with control rats, whereas β3-adrenoceptors and multidrug resistance-associated protein expression remained unchanged. Direct stimulation of adenylate cyclase with forskolin or administration of 3',5'-cyclic adenosine monophosphate suggests that subtle impairments also occurred beside the down-regulation of β1-adrenoceptor.

CONCLUSIONS

The positive inotropic effect of β-adrenoceptor stimulation is slightly decreased in Zucker obese rats and was more markedly decreased in Zucker diabetic rats. These decreases are mainly related to β1-adrenoceptor down-regulation.

Influence of body composition on survival in patients with head and neck cancer

BACKGROUND

Recent evidence has suggested links between obesity and outcomes for various types of cancer. This study investigates the impact that body composition has on survival in patients with head and neck cancer.

METHODS

Data prospectively collected from 578 patients were analyzed using Cox regression models to determine independent associations that pretreatment body mass index (BMI) and 3-month weight change have on observed survival.

RESULTS

Higher BMIs were associated with better survival (p < .001). Five-year rates ranged from 33.8% for underweight to 75.3% for overweight/obese patients. Patients with stable weight had the highest 5-year rate (72.6%; p = .019), whereas patients who gained ≥5% had worse survival (45.8%) than those who lost ≥5% (65.8%). BMI independently predicted survival, whereas weight change was not an independent predictor.

CONCLUSION

This demonstrated association between BMI and survival provides useful information when offering prognoses and investigating optimal treatments © 2015 Wiley Periodicals, Inc. Head Neck 38: E261-E267, 2016.

Physiological and management implications of obesity in critical illness

Obesity is highly prevalent in the United States and is becoming increasingly common worldwide. The anatomic and physiological changes that occur in obese individuals may have an impact across the spectrum of critical illness. Obese patients may be more susceptible to hypoxemia and hypercapnia. During mechanical ventilation, elevated end-expiratory pressures may be required to improve lung compliance and to prevent ventilation-perfusion mismatch due to distal airway collapse. Several studies have shown an increased risk of organ dysfunction such as the acute respiratory distress syndrome and acute kidney injury in obese patients. Predisposition to ventricular hypertrophy and increases in blood volume should be considered in fluid management decisions. Obese patients have accelerated muscle losses in critical illness, making nutrition essential, although the optimal predictive equation to estimate nutritional needs or formulation for obese patients is not well established. Many common intensive care unit medications are not well studied in obese patients, necessitating understanding of pharmacokinetic concepts and consultation with pharmacists. Obesity is associated with higher risk of deep venous thrombosis and catheter-associated bloodstream infections, likely related to greater average catheter dwell times. Logistical issues such as blood pressure cuff sizing, ultrasound assistance for procedures, diminished quality of some imaging modalities, and capabilities of hospital equipment such as beds and lifts are important considerations. Despite the physiological alterations and logistical challenges involved, it is not clear whether obesity has an effect on mortality or long-term outcomes from critical illness. Effects may vary by type of critical illness, obesity severity, and obesity-associated comorbidities.

Outcomes and prognostic factors in patients with prolonged acute mechanical ventilation: A single-center study in Korea

PURPOSE

The purpose of the study is to evaluate outcomes and objective parameters related to poor prognosis in patients who were defined as prolonged acute mechanical ventilation (PAMV; ventilator care ≥96 hours) in the medical intensive care unit of a university-affiliated tertiary care hospital in Korea.

MATERIAL AND METHODS

We analyzed retrospectively clinical data gathered from the medical records on day 4 of MV between 2008 and 2013. In total, 311 were categorized as PAMV.

RESULTS

Their median age was 67 years (range, 18-93 years), and 71.7% were male. The 28-day mortality rate after intensive care unit admission was 34.7%. Four variables on day 4 of mechanical ventilation (need for neuromuscular blockers [hazard ratio {HR}, 2.432; 95% confidence interval, 1.337-4.422], need for vasopressors [HR, 2.312; 95% confidence interval, 1.258-4.248], need for hemodialyses [HR, 1.913; 95% confidence interval, 1.018-3.595], and body mass index ≤21 kg/m(2) [HR, 1.827; 95% confidence interval, 1.015-3.288]) were independent factors associated with mortality based on a Cox proportional hazards model. As the number of these prognostic factors increased, the survival rate decreased.

CONCLUSIONS

Four clinical factors (body mass index ≤21, requirement for neuromuscular blockers, vasopressors, and hemodialysis) on day 4 of mechanical ventilation were associated with 28-day mortality in PAMV patients.

Designing drug regimens for special intensive care unit populations

This review is intended to help clinicians design drug regimens for special populations of critically ill patients with extremes of body size, habitus and composition that make drug choice or dosing particularly challenging due to the lack of high-level evidence on which to make well-informed clinical decisions. The data sources included a literature search of MEDLINE and EMBASE with reviews of reference lists of retrieved articles. Abstracts of original research investigations and review papers were reviewed for their relevance to drug choice or dosing in the following special critically ill populations: patients with more severe forms of bodyweight or height, patients with amputations or missing limbs, pregnant patients, and patients undergoing extracorporeal membrane oxygenation or plasma exchange. Relevant papers were retrieved and evaluated, and their associated reference lists were reviewed for citations that may have been missed through the electronic search strategy. Relevant original research investigations and review papers that could be used to formulate general principles for drug choice or dosing in special populations of critically ill patients were extracted. Randomized studies with clinically relevant endpoints were not available for performing quantitative analyses. Critically ill patients with changes in body size, habitus and composition require special consideration when designing medication regimens, but there is a paucity of literature on which to make drug-specific, high-level evidence-based recommendations. Based on the evidence that is available, general recommendations are provided for drug choice or dosing in special critically ill populations.

Sedation options for the morbidly obese intensive care unit patient: a concise survey and an agenda for development

Background

We offer some perspectives and commentary on the sedation of obese patients in the intensive care unit (ICU).

Discussion

Sedation in morbidly obese patients should conform to the same broad principles now current in ICU practice. These include a general presumption against benzodiazepines as first-line agents. Opioids should be avoided in any situation where spontaneous breathing is required. Remifentanil is the preferred agent where continuous stable opioid levels using an infusion are required, because of its lack of context-sensitive accumulation. Volatile anaesthetics may be an option for the same reason but there are no substantial, controlled demonstrations of effectiveness/safety in short-term use in the ICU setting. Propofol is a valuable resource in the morbidly obese patients but the duration of continuous sedation should not exceed 6 days, in order to avoid propofol infusion syndrome. Alpha-2 agonists offer a range of theoretically positive features for the sedation of morbidly obese patients, but at present there is a lack of pharmacokinetic data and a critical mass of high-grade clinical data. Dexmedetomidine has the attraction of not causing respiratory depression or obstructive breathing during sedation and its sympatholytic effects should help deliver stable blood pressure and heart rate. Ketamine has a poor tolerability profile in adults so its use in the ICU context is largely confined to paediatrics.

Conclusion

None of the agents currently available is ideal for every situation encountered in the management of morbidly obese patients. This article identifies additional research needed to place sedation practice of obese patients on a more systematic footing.

Proceedings From FDA/A.S.P.E.N. Public Workshop: Clinical Trial Design for Intravenous Fat Emulsion Products, October 29, 2013

The development of intravenous fat emulsion (IVFE) is the culmination of physiological, biochemical, nutritional, and medical scientific advancements. IVFEs have the ability to deliver critical nutritional substrates to the patient. Recent literature purports that they may also play roles in modulation of immune functionality and pulmonary physiology, but data supporting these potential benefits are limited. While soybean-based IVFEs have comprised the dominant fat in U.S. markets, a number of other novel IVFEs may prove to optimize the care of children and adults in both hospitalized and home settings. The October 2013 U.S. Food and Drug Administration (FDA)/American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) Public Workshop brought together scientists, researchers, and clinical experts to present updated clinical perspectives of IVFEs, including historical development, current state of usage throughout the world, and considerations for the regulatory approval of new IVFEs in the United States.

The association between obesity and outcomes in critically ill patients

BACKGROUND

Obesity rates are increasing worldwide, particularly in North America. The impact of obesity on the outcome of critically ill patients is unclear.

METHODS

A prospective observational cohort study of consecutive patients admitted to a tertiary critical care unit in Canada between January 10, 2008 and March 31, 2009 was conducted. Exclusion criteria were age <18 years, admission <24 h, planned cardiac surgery, pregnancy, significant ascites, unclosed surgical abdomen and brain death on admission. Height, weight and abdominal circumference were measured at the time of intensive care unit (ICU) admission. Coprimary end points were ICU mortality and a composite of ICU mortality, reintubation, ventilator-associated pneumonia, line sepsis and ICU readmission. Subjects were stratified as obese or nonobese, using two separate metrics: body mass index (BMI) ≥ 30 kg/m(2) and a novel measurement of 75th percentile for waist-to-height ratio (WHR).

RESULTS

Among 449 subjects with a BMI ≥ 18.5 kg/m(2), both BMI and WHR were available for comparative analysis in 348 (77.5%). Neither measure of obesity was associated with the primary end points. BMI ≥ 3 0 kg/m(2) was associated with a lower odds of six-month mortality than the BMI <30 kg/m(2) group (adjusted OR 0.59 [95% CI 0.36 to 0.97]; P=0.04) but longer intubation times (adjusted RR 1.56 [95% CI 1.17 to 2.07]; P=0.003) and longer ICU length of stay (adjusted RR 1.67 [95% CI 1.21 to 2.31]; P=0.002). Conversely, measurement of 75th percentile for WHR was associated only with decreased ICU readmission (OR 0.23 [95% CI 0.07 to 0.79]; P=0.02).

CONCLUSIONS

Obesity was not necessarily associated with worse outcomes in critically ill patients.

Obesity and nutrition in acute respiratory distress syndrome

This article discusses obesity, its contribution to clinical outcomes, and the current literature on nutrition. More than one third of Americans are obese. Literature suggests that, among critically ill patients, the relationship between obesity and outcomes is complex. Obese patients may be at greater risk of developing acute respiratory distress syndrome (ARDS) than normal weight patients. Although obesity may confer greater morbidity in intensive care, it seems to decrease mortality. ARDS is a catabolic state; patients demonstrate a profound inflammatory response, multiple organ dysfunction, and hypermetabolism, often with malnutrition. The concept of pharmaconutrition has emerged.

Obesity in kidney disease: A heavyweight opponent

Obesity is an important worldwide challenge that must be faced in most developed and developing countries because of unhealthy nutritional habits. The consequences of obesity and being overweight are observed in different organs, but the kidney is one of the most affected. Excess adipose tissue causes hemodynamic alterations in the kidney that can result in renal disease. However, obesity is also commonly associated with other comorbidities such as chronic inflammation, hypertension and diabetes. This association of several aggravating factors is still a matter of concern in clinical and basic research because the pathophysiologic mechanisms surrounding chronic kidney disease development in obese patients remain unclear. This review will discuss the consequences of obesity in the context of renal injury.

Weight-for-age distribution and case-mix adjusted outcomes of 14,307 paediatric intensive care admissions

Aims

To determine whether the paediatric intensive care (PIC) population weight distribution differs from the UK reference population and whether weight-for-age at admission is an independent risk factor for mortality.

Methods

Admission weight-for-age standard deviation scores (SDS) were calculated for all PIC admissions (March 2003–December 2011) to Great Ormond Street Hospital: this is the number of standard deviations (SD) between a child’s weight and the UK mean weight-for-age. Categorised into nine SDS groups, standardised mortality ratios (SMR) and logistic regression were used to assess the relationship between weight-for-age at admission and risk-adjusted mortality.

Results

Out of 12,458 admissions, mean weight-for-age was 1.04 SD below the UK reference population mean (p < 0.0001). Based on 942 deaths, risk-adjusted mortality was lowest in those with mild-to-moderately raised weight-for-age (SDS 0.5–2.5) and highest in children with extreme under- or overweight (SDS < −3.5 and SDS > +3.5). Logistic regression indicated that age, gender, ethnicity and weight-for-age are independent risk factors for mortality. South Asian and ‘other’ ethnicities had significantly increased risk of death compared to children of white and black ethnic origin.

Conclusion

The PIC population mean weight-for-age is significantly lower than the UK reference mean. The extremes of weight-for-age are over-represented, especially underweight. Weight-for-age at admission is an independent risk factor for mortality. A U-shaped association between weight and risk-adjusted mortality exists, with the lowest risk of death in children who are mild-to-moderately overweight. Future studies should determine the impact of malnutrition on risk-adjusted mortality and investigate the aetiology of risk disparities with ethnicity.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-014-3381-x) contains supplementary material, which is available to authorized users.

Development of a murine model of early sepsis in diet-induced obesity

Sepsis, a global health issue, is the most common cause of mortality in the intensive care unit. The aim of this study was to develop a new model of sepsis that investigates the impact of prolonged western diet (WD) induced obesity on the response to early sepsis. Male C57BL/6 mice were fed either a high fat WD or normal chow diet (NCD) for 6, 15, or 27 weeks. Septic obese mice at 15 and 27 weeks had significantly lower levels of lung myeloperoxidase (26.3 ± 3.80 U/mg tissue) compared to age matched ad lib (44.1 ± 2.86 U/mg tissue) and diet restricted (63.2 ± 5.60 U/mg tissue) controls. Low levels of lung inflammation were not associated with changes in hepatic cytokines and oxidative stress levels. Obese mice had significantly (P < 0.0001) larger livers compared to controls. Histological examination of the livers demonstrated that WD fed mice had increased inflammation with pronounced fat infiltration, steatosis, and hepatocyte ballooning. Using this model of prolonged exposure to high fat diet we have data that agree with recent clinical observations suggesting obese individuals are protected from sepsis-induced lung injury. This model will allow us to investigate the links between damage to the hepatic microcirculation, immune response, and lung injury.

Influence of body mass index on mortality after surgery for perforated peptic ulcer

BACKGROUND

Body mass index (BMI) is a strong predictor of mortality in the general population. In spite of the medical hazards of obesity, a protective effect on mortality has been suggested in surgical patients: the obesity paradox. The aim of the present nationwide cohort study was to examine the association between BMI and mortality in patients treated surgically for perforated peptic ulcer (PPU).

METHODS

This was a national prospective cohort study of all Danish patients treated surgically for PPU between 1 February 2003 and 31 August 2009, for whom BMI was registered. Non-surgically treated patients and those with malignant ulcers were excluded. The primary outcome measure was 90-day mortality. The association between BMI and mortality was calculated as crude and adjusted relative risks (RRs) with 95 per cent confidence intervals (c.i.).

RESULTS

Of 2668 patients who underwent surgical treatment for PPU, 1699 (63.7 per cent) had BMI recorded. Median age was 69.4 (range 17.6-100.9) years and 53.7 per cent of the patients were women. Some 1126 patients (66.3 per cent) had at least one of six co-morbid diseases; 728 (42.8 per cent) had an American Society of Anesthesiologists grade of III or more. A total of 471 patients (27.7 per cent) died within 90 days of surgery. Being underweight was associated with a more than twofold increased risk of death following surgery for PPU (adjusted RR 2.26, 95 per cent c.i. 1.37 to 3.71). No statistically significant association was found between obesity and mortality.

CONCLUSION

Being underweight was associated with increased mortality in patients with PPU, whereas being overweight or obese was neither protective nor an adverse prognostic factor.

Obesity paradox in cancer: new insights provided by body composition

BACKGROUND

Obesity, defined by body mass index (BMI), appears to have a paradoxical protective effect in several chronic diseases.

OBJECTIVE

We investigated the obesity paradox in cancer patients by using body composition.

DESIGN

The study was an observational study of 175 cancer patients assessed before chemotherapy. Obesity was defined as BMI (in kg/m(2)) ≥30 or fat mass index (FMI; fat mass divided by the square of height) ≥5.2 (men) and ≥8.2 (women) measured by using a bioelectrical impedance analysis. Low muscle mass (sarcopenia) was defined as fat-free mass index (fat-free mass divided by the square of height) <17.5 (men) and <15.1 (women).

RESULTS

Most patients were women (65.7%) and had a mean (±SD) age of 56.9 ± 12.8 y. According to BMI criteria, 60% of patients were overweight or obese. The median survival time for overweight (2.64 y; range: 0.23-3.16 y) and obese (2.61 y; range: 0.26-3.20 y) patients was significantly higher than for patients with a normal (2.04 y; range: 0.06-3.05 y) or low (0.52 y; range: 0.19-0.98 y) BMI (P < 0.001). Sarcopenic patients had shorter survival, regardless of their FMI. Obesity predicted higher survival rates only when sarcopenia was absent. In a multivariate Cox regression model, sarcopenia was an independent predictor of higher mortality (HR: 5.19; 95% CI: 2.58, 10.43) after we controlled for BMI, age, and tumor stage.

CONCLUSIONS

The obesity paradox is present in cancer patients only when obesity is defined by BMI. Patients with sarcopenic obesity had the poorest prognosis. Cancer patients with high mortality risk can be identified by a body-composition assessment.

Veno-venous extracorporeal membrane oxygenation in obese surgical patients with hypercapnic lung failure

BACKGROUND

In patients with a body mass index (BMI) > 35 kg/m(2) , or in extreme cases weighting > 250 kg, we are faced with special challenges in therapy and logistics. The aim was to analyze the feasibility of the extracorporeal membrane oxygenation (ECMO) in these patients.

METHODS

We report 12 adult patients [10 male, 2 female; mean age 56.7 (34-74) years; mean BMI 47.9 (35-88.6) kg/m(2) ] with acute lung failure treated with veno-venous ECMO from 1 January 2009 to 30 June 2013. All patients were cannulated percutaneously into the right internal jugular vein and one of the femoral veins at the bedside.

RESULTS

The mean time to ECMO after admission to the intensive care unit (ICU) was 2 days (0-10), and the mean ECMO run time was 9 days (4 h-20 days). Lung failure occurred in the contexts of wound infection (two patients), anaphylactic shock (one patient), major trauma (one patients) and pneumonia after surgery (four patients), and respiratory failure in abdominal sepsis (four patients). The mean time in the ICU was 31 days (0-89), and the mean time at the hospital was 38 days (0-101). Three patients died on the system because of multiorgan failure; nine patients were weaned from ECMO (75%); and six were patients discharged from the ICU and from the hospital (survival rate 50%).

CONCLUSIONS

ECMO in obese patients is feasible and life saving. Therefore, a percutaneous cannulation remains feasible. The goals of the ECMO therapy include early spontaneous breathing, tracheotomy, rapid reduction of sedation and adequate analgesia. Rehabilitation includes nutritional therapy, as well as psychiatric therapy and bariatric surgery, as perspectives for the future.

The obesity paradox and acute kidney injury: beneficial effects of hyper-inflammation?

In the general population, obesity is associated with an increased mortality risk, whereas several epidemiological studies demonstrated a protective effect of obesity in critically ill patients. In this context, Sleeman and colleagues investigated the effects of obesity on kidney function in a well-established porcine model of cardiopulmonary bypass. The authors confirm literature data that obesity per se is associated with a chronic hyper-inflammatory status. Nevertheless, obese swine undergoing the surgical procedure presented with attenuated kidney dysfunction and tissue apoptosis. The authors suggest that the chronic inflammation causes pre-conditioning against excessive acute hyper-inflammation. The authors have to be commended for using a long-term, clinically relevant model that, moreover, addresses a variety of putative mechanisms. The study is discussed in the context of the controversial findings that, in contrast to the existing literature on improved survival, most studies available suggest a higher incidence and severity of acute kidney injury in obese patients when compared with lean controls.

[An immunohistochemical study of various breast tissues using CA15-3 (MAb 115D8 and MAb DF3)]

A CA15-3 RIA KIT, composed with two different monoclonal antibodies (115D 8 and DF 3), has been seen to react with the sera of breast cancer patients. Although the subclass of both antibodies is different, the antigen that reacted with them seems to be same, with a range from 300-450 kd. To reveal the reacting pattern of both antibodies, an immunohistochemical study was performed involving various breast tissues. In general, normal and benign breast tumors exhibited an apical stain by 115D8 and an apical and focal cytosol stain by DF 3. Breast carcinomas displayed not only an apical stain but a strong cytosol stain. However, the staining patterns showed little difference.