Being Overweight Is Associated With Greater Survival in ICU Patients: Results From the Intensive Care Over Nations Audit

Specific and Non-specific Aspects and Future Challenges of ICU Care Among COVID-19 Patients with Obesity: A Narrative Review

PURPOSE OF REVIEW

Since the end of 2019, the coronavirus disease 2019 (COVID-19) pandemic has infected nearly 800 million people and caused almost seven million deaths. Obesity was quickly identified as a risk factor for severe COVID-19, ICU admission, acute respiratory distress syndrome, organ support including mechanical ventilation and prolonged length of stay. The relationship among obesity; COVID-19; and respiratory, thrombotic, and renal complications upon admission to the ICU is unclear.

RECENT FINDINGS

The predominant effect of a hyperinflammatory status or a cytokine storm has been suggested in patients with obesity, but more recent studies have challenged this hypothesis. Numerous studies have also shown increased mortality among critically ill patients with obesity and COVID-19, casting doubt on the obesity paradox, with survival advantages with overweight and mild obesity being reported in other ICU syndromes. Finally, it is now clear that the increase in the global prevalence of overweight and obesity is a major public health issue that must be accompanied by a transformation of our ICUs, both in terms of equipment and human resources. Research must also focus more on these patients to improve their care. In this review, we focused on the central role of obesity in critically ill patients during this pandemic, highlighting its specificities during their stay in the ICU, identifying the lessons we have learned, and identifying areas for future research as well as the future challenges for ICU activity.

The obesity paradox in younger adult patients with sepsis: analysis of the MIMIC-IV database

BACKGROUND

The obesity paradox suggests that individuals with obesity may have a survival advantage against specific critical illnesses, including sepsis. However, whether this paradox occurs at younger ages remains unclear. Therefore, we aimed to investigate whether obesity could improve survival in younger adult patients with sepsis.

METHODS

We used clinical data sourced from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Patients with Sequential Organ Failure Assessment score ≥2 and suspected infection at the time of ICU admission were identified as having sepsis, following the Sepsis-3 definition. Individuals were classified into the obesity (BMI ≥30 kg/m²) and non-obesity (BMI <30 kg/m²) groups. Patients aged <50 and ≥50 years were categorized as younger adult patients and older patients, respectively.

RESULTS

Of 73,181 patients in the MIMIC-IV ICU database, 18,120 satisfied the inclusion criteria: 2642 aged <50 years and 15,478 aged ≥50 years. The Kaplan-Meier curve showed that obesity was not associated with an improved mortality rate among younger adult patients with sepsis (log-rank test: P = 0.197), while obesity exhibited a survival benefit in older patients with sepsis (log-rank test: P < 0.001). After propensity score matching, in-hospital mortality did not differ significantly between the obesity and non-obesity groups (13.3% vs. 12.2%; P = 0.457) in the younger adult patients with sepsis. Multivariate logistic regression analysis revealed that BMI was not an independent risk factor for in-hospital mortality in younger adult patients with sepsis (underweight: adjusted odds ratio [aOR] 1.72, P = 0.076; overweight: aOR 0.88, P = 0.437; obesity: aOR 0.93, P = 0.677; and severe obesity: aOR 1.22, P = 0.580, with normal weight as the reference).

CONCLUSION

Contrary to findings regarding older patients with sepsis, our findings suggest that the obesity paradox does not apply to younger adult patients with sepsis.

Association of anthropometric measures with all-cause and cause-specific mortality in US adults: revisiting the obesity paradox

OBJECTIVE

Previous studies have shown that the obesity paradox exists in a variety of clinical settings, whereby obese individuals have lower mortality than their normal-weight counterparts. It remains unclear whether the association between obesity and mortality risk varies by anthropometric measures. The purpose of this study is to examine the association between various anthropometric measures and all-cause and cause-specific mortality in US adults.

METHODS

This cohort study included data from the National Health and Nutrition Examination Survey between 2009 and 2018, with a sample size of 28,353 individuals weighted to represent 231 million US adults. Anthropometric measurements were obtained by trained technicians using standardized methods. Mortality data were collected from the date of enrollment through December 31, 2019. Weighted Cox proportional hazards models, restricted cubic spline curves, and cumulative incidence analyses were performed.

RESULTS

A total of 2091 all-cause deaths, 606 cardiovascular deaths, 519 cancer deaths, and 966 other-cause deaths occurred during a median follow-up of 5.9 years. The association between body mass index (BMI) and mortality risk was inversely J-shaped, whereas the association between waist-to-height ratio (WHtR) and mortality risk was positively J-shaped. There was a progressive increase in the association between the WHtR category and mortality risk. Compared with the reference category of WHtR < 0.5, the estimated hazard ratio (HR) for all-cause mortality was 1.004 (95% confidence interval [CI] 1.001-1.006) for WHtR 0.50-0.59, 1.123 (95% CI 1.120-1.127) for WHtR 0.60-0.69, 1.591 (95% CI 1.584-1.598) for WHtR 0.70-0.79, and 2.214 (95% CI 2.200-2.228) for WHtR ≥ 0.8, respectively. Other anthropometric indices reflecting central obesity also showed that greater adiposity was associated with higher mortality.

CONCLUSIONS

Anthropometric measures reflecting central obesity were independently and positively associated with mortality risk, eliminating the possibility of an obesity paradox.

Dosing Regimen for Cefotaxime Should Be Adapted to the Stage of Renal Dysfunction in Critically Ill Adult Patients-A Retrospective Study

Cefotaxime administration is recommended in doses of 3-12 g/day in adults with a Glomerular Filtration Rate (GFR) > 5 mL/min. This study aimed to assess the impact of renal function and obesity on cefotaxime concentrations in intensive care unit (ICU) patients. A retrospective cohort study was conducted on consecutive ICU patients receiving continuous cefotaxime infusion between 2020 and 2022 [IRBN992021/CHUSTE]. Doses were not constant; consequently, a concentration-to-dose ratio (C/D) was considered. Statistical analysis was performed to assess the relationship between cefotaxime concentrations, renal function, and obesity. A total of 70 patients, median age 61 years, were included, with no significant difference in cefotaxime concentrations between obese and non-obese patients. However, concentrations varied significantly by GFR, with underdosing prevalent in patients with normal to increased renal function and overdosing in those with severely impaired renal function. Adjustment of cefotaxime dosing according to GFR was associated with improved target attainment. Cefotaxime dosing in critically ill patients should consider renal function, with higher initial doses required in patients with normal to increased GFR and lower doses in those with severely impaired renal function. Therapeutic drug monitoring may aid in optimising dosing regimens. Prospective studies are warranted to validate these findings and inform clinical practice.

The impact of obesity on ventilator-associated pneumonia, a US nationwide study

BACKGROUND

Ventilator-associated pneumonia (VAP) is one of the leading causes of mortality in patients with critical care illness. Since obesity is highly prevalent, we wanted to study its impact on the outcomes of patients who develop VAP.

METHODS

Using the National Inpatient Sample (NIS) database from 2017 to 2020, we conducted a retrospective study of adult patients with a principal diagnosis of VAP with a secondary diagnosis with or without obesity according to 10th revision of the International Statistical Classification of Diseases (ICD-10) codes. Several demographics, including age, race, and gender, were analyzed. The primary endpoint was mortality, while the secondary endpoints included tracheostomy, length of stay in days, and patient charge in dollars. Multivariate logistic regression model analysis was used to adjust for confounders, with a p-value less than 0.05 considered statistically significant.

RESULTS

The study included 3832 patients with VAP, 395 of whom had obesity. The mean age in both groups was around 58 years, and 68% of the group with obesity were females compared to 40% in females in the group without obesity. Statistically significant comorbidities in the obesity group included a Charlson Comorbidity Index score of three and above, diabetes mellitus, hypertension, chronic kidney disease, and sleep apnea. Rates and odds of mortality were not significantly higher in the collective obesity group 39 (10%) vs. 336 (8.5%), p-value 0.62, adjusted odds ratio 1.2, p-value 0.61). The rates and odds of tracheostomy were higher in the obesity group but not statistically significant. Obese patients were also found to have a longer hospitalization. Upon subanalysis of the data, no evidence of racial disparities was found in the care of VAP for both the obese and control groups.

CONCLUSIONS

Obesity was not found to be an independent risk factor for worse outcomes in patients who develop VAP in the intensive care unit.

Physical and respiratory therapy in the critically ill patient with obesity: a narrative review

Obesity has become increasingly prevalent in the intensive care unit, presenting a significant challenge for healthcare systems and professionals, including rehabilitation teams. Caring for critically ill patients with obesity involves addressing complex issues. Despite the well-established and safe practice of early mobilization during critical illness, in rehabilitation matters, the diverse clinical disturbances and scenarios within the obese patient population necessitate a comprehensive understanding. This includes recognizing the importance of metabolic support, both non-invasive and invasive ventilatory support, and their weaning processes as essential prerequisites. Physiotherapists, working collaboratively with a multidisciplinary team, play a crucial role in ensuring proper assessment and functional rehabilitation in the critical care setting. This review aims to provide critical insights into the key management and rehabilitation principles for obese patients in the intensive care unit.

Early Sepsis-Associated Acute Kidney Injury and Obesity

Importance

The prevalence of obesity is increasing in the intensive care unit (ICU). Although obesity is a known risk factor for chronic kidney disease, its association with early sepsis-associated acute kidney injury (SA-AKI) and their combined association with patient outcomes warrant further investigation.

Objective

To explore the association between obesity, early SA-AKI incidence, and clinical outcomes in patients with sepsis.

Design, Setting, and Participants

This nationwide, prospective cohort study analyzed patients aged 19 years or older who had sepsis and were admitted to 20 tertiary hospital ICUs in Korea between September 1, 2019, and December 31, 2021. Patients with preexisting stage 3A to 5 chronic kidney disease and those with missing body mass index (BMI) values were excluded.

Exposures

Sepsis and hospitalization in the ICU.

Main Outcomes and Measures

The primary outcome was SA-AKI incidence within 48 hours of ICU admission, and secondary outcomes were mortality and clinical recovery (survival to discharge within 30 days). Patients were categorized by BMI (calculated as weight in kilograms divided by height in meters squared), and data were analyzed by logistic regression adjusted for key characteristics and clinical factors. Multivariable fractional polynomial regression models and restricted cubic spline models were used to analyze the clinical outcomes with BMI as a continuous variable.

Results

Of the 4041 patients (median age, 73 years [IQR, 63-81 years]; 2349 [58.1%] male) included in the study, 1367 (33.8%) developed early SA-AKI. Obesity was associated with a higher incidence of SA-AKI compared with normal weight (adjusted odds ratio [AOR], 1.40; 95% CI, 1.15-1.70), as was every increase in BMI of 10 (OR, 1.75; 95% CI, 1.47-2.08). While obesity was associated with lower in-hospital mortality in patients without SA-AKI compared with their counterparts without obesity (ie, underweight, normal weight, overweight) (AOR, 0.72; 95% CI, 0.54-0.94), no difference in mortality was observed in those with SA-AKI (AOR, 0.85; 95% CI, 0.65-1.12). Although patients with obesity without SA-AKI had a greater likelihood of clinical recovery than their counterparts without obesity, clinical recovery was less likely among those with both obesity and SA-AKI.

Conclusions and Relevance

In this cohort study of patients with sepsis, obesity was associated with a higher risk of early SA-AKI and the presence of SA-AKI modified the association of obesity with clinical outcomes.

Outcomes in Obese Adult Veno-Venous Extracorporeal Membrane Oxygenation: A Systematic Review

Obesity is associated with an overall increased risk of morbidity and mortality. However, in patients with critical illness, sepsis, and acute respiratory distress syndrome, obesity may be protective, termed "the obesity paradox." This is a systematic literature review of articles published from 2000 to 2022 evaluating complications and mortality in adults with respiratory failure on veno-venous extracorporeal membrane oxygenation (VV ECMO) based on body mass index (BMI). Eighteen studies with 517 patients were included. Common complications included acute renal failure (175/377, 46.4%), venous thrombosis (175/293, 59.7%), and bleeding (28/293, 9.6%). Of the six cohort studies, two showed improved mortality among obese patients, two showed a trend toward improved mortality, and two showed no difference. Comparing all patients in the studies with BMI of less than 30 to those with BMI of greater than or equal to 30, we noted decreased mortality with obesity (92, 37.1% of BMI <30 vs. 30, 11% of BMI ≥30, p ≤ 0.0001). Obesity may be protective against mortality in adult patients undergoing VV ECMO. Morbid and super morbid obesity should not be considered a contraindication to cannulation, with patients with BMI ≥ 80 surviving to discharge. Complications may be high, however, with higher rates of continuous renal replacement therapy and thrombosis among obese patients.

Lower quality of life in obese ICU survivors: a multicenter cohort study

PURPOSE

To compare health-related quality of life (HRQoL) and functional status between obese, underweight, normal-weight, and overweight patients after three months post-intensive care unit (ICU) discharge.

METHODS

Multicenter cohort study (10 Brazilian ICUs). 1600 ICU survivors (≥ 72 h in the ICU) were included.The main outcomes were HRQoL and functional status assessed three months after the ICU discharge. The secondary outcomes were mortality, hospital readmission, and ICU readmission during the same period.

RESULTS

Obese patients (median 50.1; IQR 39.6-59.6) had lower HRQoL in the mental component than normal-weight patients (median 53; IQR 45.6-60.1) (p = 0.033). No differences were found between BMI categories regarding the physical component of HRQoL and the Barthel Index (p = 0.355 and 0.295, respectively). Regarding readmissions, 65.1 and 25.1% of patients were readmitted to the hospital and ICU, but there was no difference between the groups (p = 0.870 and 0.220, respectively). Obese patients died less frequently (11.8%) than underweight (30.9%) and normal-weight (19.3%) patients (p < 0.001).

CONCLUSION

After three months of post-ICU discharge, obese patients had lower HRQoL in the mental component than normal-weight patients. However, obese patients died less than underweight and normal-weight patients.

Obesity and Extracorporeal Membrane Oxygenation (ECMO): Analysis of Outcomes

Traditionally, patients with obesity have been deemed ineligible for extracorporeal life support (ELS) therapies such as extracorporeal membrane oxygenation (ECMO), given the association of obesity with chronic health conditions that contribute to increased morbidity and mortality. Nevertheless, a growing body of literature suggests the feasibility, efficacy, and safety of ECMO in the obese population. This review provides an in-depth analysis of the current literature assessing the effects of obesity on outcomes among patients supported with ECMO (venovenous [VV] ECMO in noncoronavirus disease 2019 and coronavirus disease 2019 acute respiratory distress syndrome, venoarterial [VA] ECMO, and combined VV and VA ECMO), offer a possible explanation of the current findings on the basis of the obesity paradox phenomenon, provides a framework for future studies addressing the use of ELS therapies in the obese patient population, and provides guidance from the literature for many of the challenges related to initiating, maintaining, and weaning ELS therapy in patients with obesity.

Using Signal Features of Functional Near-Infrared Spectroscopy for Acute Physiological Score Estimation in ECMO Patients

Extracorporeal membrane oxygenation (ECMO) is a vital emergency procedure providing respiratory and circulatory support to critically ill patients, especially those with compromised cardiopulmonary function. Its use has grown due to technological advances and clinical demand. Prolonged ECMO usage can lead to complications, necessitating the timely assessment of peripheral microcirculation for an accurate physiological evaluation. This study utilizes non-invasive near-infrared spectroscopy (NIRS) to monitor knee-level microcirculation in ECMO patients. After processing oxygenation data, machine learning distinguishes high and low disease severity in the veno-venous (VV-ECMO) and veno-arterial (VA-ECMO) groups, with two clinical parameters enhancing the model performance. Both ECMO modes show promise in the clinical severity diagnosis. The research further explores statistical correlations between the oxygenation data and disease severity in diverse physiological conditions, revealing moderate correlations with the acute physiologic and chronic health evaluation (APACHE II) scores in the VV-ECMO and VA-ECMO groups. NIRS holds the potential for assessing patient condition improvements.

Towards optimization of ceftazidime dosing in obese ICU patients: the end of the 'one-size-fits-all' approach?

BACKGROUND

Ceftazidime is commonly used as a key antibiotic against Pseudomonas aeruginosa in critically ill patients. ICU patients have severely altered and variable antibiotic pharmacokinetics, resulting in lower antimicrobial concentrations and potentially poor outcome. Several factors, including obesity and renal function, may influence pharmacokinetics. Thus, the objective of the study was to evaluate the impact of obesity and renal function on ceftazidime plasma concentrations and dosing regimen in ICU patients.

METHODS

All consecutive adult patients from six ICUs, treated with continuous ceftazidime infusion and under therapeutic drug monitoring evaluation, were included. Obesity was defined as BMI ≥30 kg/m². Glomerular filtration rate (GFR) was estimated by the Chronic Kidney Disease Epidemiology Collaboration formula. The ceftazidime recommended target for plasma concentrations was between 35 and 80 mg/L.

RESULTS

A total of 98 patients (45 obese), with an average weight of 90 (±25) kg, were included. Mean GFR was 84.1 (±40.4) mL/min/1.73 m2. Recommended ceftazidime plasma concentrations were achieved for only 48.0% of patients, with median dosing regimen of 6 g/day. Obese patients had lower ceftazidime plasma concentrations compared with non-obese patients (37.8 versus 56.3 mg/L; P = 0.0042) despite similar dosing regimens (5.83 g/day versus 5.52 g/day, P = 0.2529). Almost all augmented renal clearance patients were underdosed despite ceftazidime dosing of 6.6 (±0.8) g/day. Weight-based ceftazidime dosing seemed to attenuate such obesity-related discrepancies, regardless of GFR.

CONCLUSIONS

Obese ICU patients required significantly greater ceftazidime doses to achieve the target range. A tailored dosing regimen may be considered based on weight and GFR. Future prospective studies should be performed to confirm this individualized dosing approach.

The impact of body mass index on long-term survival after ICU admission due to COVID-19: A retrospective multicentre study

Objective

The impact of obesity on long-term survival after intensive care unit (ICU) admission with severe coronavirus disease 2019 (COVID-19) is unclear. We aimed to quantify the impact of obesity on time to death up to two years in patients admitted to Australian and New Zealand ICUs.

Design

Retrospective multicentre study.

Setting

92 ICUs between 1st January 2020 through to 31st December 2020 in New Zealand and 31st March 2022 in Australia with COVID-19, reported in the Australian and New Zealand Intensive Care Society adult patient database.

Participants

All patients with documented height and weight to estimate the body mass index (BMI) were included. Obesity was classified patients according to the World Health Organization recommendations.

Interventions and main outcome measures

The primary outcome was survival time up to two years after ICU admission. The effect of obesity on time to death was assessed using a Cox proportional hazards model. Confounders were acute illness severity, sex, frailty, hospital type and jurisdiction for all patients.

Results

We examined 2,931 patients; the median BMI was 30.2 (IQR 25.6-36.0) kg/m2. Patients with a BMI ≥30 kg/m2 were younger (median [IQR] age 57.7 [46.2-69.0] vs. 63.0 [50.0-73.6]; p < 0.001) than those with a BMI <30 kg/m2. Most patients (76.6%; 2,244/2,931) were discharged alive after ICU admission. The mortality at two years was highest for BMI categories <18.5 kg/m2 (35.4%) and 18.5-24.9 kg/m2 (31.1%), while lowest for BMI ≥40 kg/m2 (14.5%). After adjusting for confounders and with BMI 18.5-24.9 kg/m2 category as a reference, only the BMI ≥40 kg/m2 category patients had improved survival up to 2 years (hazard ratio = 0.51; 95%CI: 0.34-0.76).

Conclusions

The obesity paradox appears to exist beyond hospital discharge in critically ill patients with COVID-19 admitted in Australian and New Zealand ICUs. A BMI ≥40 kg/m2 was associated with a higher survival time of up to two years.

The relationship between body mass index and mortality is not linear in patients requiring venovenous extracorporeal support

OBJECTIVE

Morbid obesity may influence candidacy for venovenous extracorporeal membrane oxygenation (VVECMO) support. Indeed, body mass index (BMI) >40 is considered to be a relative contraindication due to increased mortality observed in patients with BMI above this value. There is scant evidence to characterize this relationship beyond speculating about the technical challenges of cannulation and difficulty in optimizing flows. We examined a national cohort to evaluate the influence of BMI on mortality in patients requiring VVECMO for severe acute respiratory syndrome coronavirus 2 infection.

METHODS

We performed a retrospective cohort analysis on National COVID Cohort Collaborative data evaluating 1,033,229 patients with BMI ≤60 from 31 US hospital systems diagnosed with severe acute respiratory syndrome virus coronavirus 2 infection from September 2019 to August 2022. We performed univariate and multivariable mixed-effects logistic regression analysis on data pertaining to those who required VVECMO support during their hospitalization. A subgroup risk-adjusted analysis comparing ECMO mortality in patients with BMI 40 to 60 with the 25th, 50th, and 75th BMI percentile was performed. Outcomes of interest included BMI, age, comorbidity score, body surface area, and ventilation days.

RESULTS

A total of 774 adult patients required VVECMO. Of these, 542 were men, median age was 47 years, mean adjusted Charlson Comorbidity Index was 1, and median BMI was 33. Overall mortality was 47.8%. There was a nonsignificant overall difference in mortality across hospitals (SD, 0.31; 95% CI, 0-0.57). After mixed multivariable logistic regression analysis, advanced age (P < .0001) and Charlson Comorbidity Index (P = .009) were each associated with increased mortality. Neither gender (P = .14) nor duration on mechanical ventilation (P = .39) was associated with increased mortality. An increase in BMI from 25th to 75th percentile was not associated with a difference in mortality (P = .28). In our multivariable mixed-effects logistic regression analysis, there exists a nonlinear relationship between BMI and mortality. Between BMI of 25 and 32, patients experienced an increase in mortality. However, between BMI of 32 and 37, the adjusted mortality in these patients subsequently decreased. Our subgroup analysis comparing BMIs 40 to 60 with the 25th, 50th, and 75th percentile of BMI found no significant difference in ECMO mortality between BMI values of 40 and 60 with the 25th, 50th, 75th percentile.

CONCLUSIONS

Advancing age and higher CCI are each associated with increased risk for mortality in patients requiring VVECMO. A nonlinear relationship exists between mortality and BMI and those between 32 and 37 have lower odds of mortality than those between BMI 25 and 32. This nonlinear pattern suggests a need for further adjudication of the contraindications associated with VVECMO, particularly those based solely on BMI.

Impact of critical illness on cholesterol and fatty acids: insights into pathophysiology and therapeutic targets

Critical illness is characterized by a hypercatabolic response encompassing endocrine and metabolic alterations. Not only the uptake, synthesis and metabolism of glucose and amino acids is majorly affected, but also the homeostasis of lipids and cholesterol is altered during acute and prolonged critical illness. Patients who suffer from critically ill conditions such as sepsis, major trauma, surgery or burn wounds display an immediate and sustained reduction in low plasma LDL-, HDL- and total cholesterol concentrations, together with a, less pronounced, increase in plasma free fatty acids. The severity of these alterations is associated with severity of illness, but the underlying pathophysiological mechanisms are multifactorial and only partly clarified. This narrative review aims to provide an overview of the current knowledge of how lipid and cholesterol uptake, synthesis and metabolism is affected during critical illness. Reduced nutritional uptake, increased scavenging of lipoproteins as well as an increased conversion to cortisol or other cholesterol-derived metabolites might all play a role in the decrease in plasma cholesterol. The acute stress response to critical illness creates a lipolytic cocktail, which might explain the increase in plasma free fatty acids, although reduced uptake and oxidation, but also increased lipogenesis, especially in prolonged critical illness, will also affect the circulating levels. Whether a disturbed lipid homeostasis warrants intervention or should primarily be interpreted as a signal of severity of illness requires further research.

Continuous Renal Replacement Therapy and Mortality in Critically Ill Obese Adults

IMPORTANCE

The outcomes of critically ill adults with obesity on continuous renal replacement therapy (CRRT) are poorly characterized. The impact of CRRT dose on these outcomes is uncertain.

OBJECTIVES

This study aimed to determine if obesity conferred a survival advantage for critically ill adults with acute kidney injury (AKI) on CRRT. Secondarily, we evaluated whether the dose of CRRT predicted mortality in this population.

DESIGN SETTING AND PARTICIPANTS

A retrospective, observational cohort study performed at an academic medical center in Minnesota. The study population included critically ill adults with AKI managed with CRRT.

MAIN OUTCOMES AND MEASURES

The primary outcome of 30-day mortality was compared between obese (body mass index [BMI] ≥ 30 kg/m2) and nonobese (BMI < 30 kg/m2) patients. Multivariable regression assessed was used to assess CRRT dose as a predictor of outcomes. An analysis included dose indexed according to actual body weight (ABW), adjusted body weight (AdjBW), or ideal body weight (IBW).

RESULTS

Among 1033 included patients, the median (interquartile range) BMI was 26 kg/m2 (23-28 kg/m2) in the nonobese group and 36 kg/m2 (32-41 kg/m2) in the obese group. Mortality was similar between groups at 30 days (54% vs. 48%; p = 0.06) but lower in the obese group at 90 days (62% vs. 55%; p = 0.02). CRRT dose predicted an increase in mortality when indexed according to ABW or AdjBW (hazard ratio [HR], 1.2-1.16) but not IBW (HR, 1.04).

CONCLUSIONS AND RELEVANCE

In critically ill adults with AKI requiring CRRT, short-term mortality appeared lower in obese patients compared with nonobese patients. Among weight calculations, IBW appears to be preferred to promote safe CRRT dosing in obese patients.

Obesity Alters cytokine signaling and gut microbiome in septic mice

Sepsis is a leading cause of mortality. Plasma cytokine levels may identify those at increased risk of mortality from sepsis. Our aim was to understand how obesity alters cytokine levels during early sepsis and its correlation with survival. Six-week-old C57BL/6 male mice were randomized to control (non-obese) or high fat diet (obese) for 5-7 weeks. Sepsis was induced by cecal ligation and perforation (CLP). Cytokine levels were measured from cheek bleeds 8 h after CLP, and mice were monitored for survival. Other cohorts were sacrificed 1 h after CLP for plasma and tissue. Septic obese mice had higher survival. At 8 h after sepsis, obese mice had higher adiponectin, leptin, and resistin but lower TNFα and IL-6 compared to non-obese mice. When stratified by 24-h survival, adipokines were not significantly different in obese and non-obese mice. TNFα and IL-6 were higher in non-obese, compared to obese, mice that died within 24 h of sepsis. Diet and to sepsis significantly impacted the cecal microbiome. IL-6 is a prognostic biomarker during early sepsis in non-obese and obese mice. A plausible mechanism for the survival difference in non-obese and obese mice may be the difference in gut microbiome and its evolution during sepsis.

Prevalence of suspected obesity hypoventilation syndrome in Hungarian Intensive Care Units during the COVID-19 pandemic

INTRODUCTION

The symptoms of obesity hypoventilation syndrome (OHS) may be present for years with concomitant progressive comorbidities, and the condition is frequently diagnosed late as a result of acute-on-chronic hypercapnic respiratory failure. Although some data exist on intensive care unit (ICU) prevalence, mortality and morbidity of OHS, little is known about the ICU mortality of these chronic respiratory failure patients during the COVID-19 pandemic.

METHODS

We performed a cross-sectional observational study in five Hungarian Intensive Care Units for 4 months during the COVID-19 pandemic. All ICU patients were screened for OHS risk factors by treating physicians. Risk factors were defined as obesity (body mass index [BMI] ≥ 30 kg/m2 ) and at least one of the following: Epworth Sleepiness Score ≥ 6; symptoms of right heart failure; daytime or night-time hypoxemia; presence of loud snoring; witnessed apnoea. We calculated prevalence, mortality and factors associated with unfavourable outcome.

RESULTS

A total of 904 ICU patients were screened for OHS risk factors. Overall 79 (8.74 ± 5.53%) patients were reported to have met the criteria for suspected OHS with a mortality rate of 40.5%; 69% (54 patients) of the cohort displayed at least 3 symptoms related to OHS before their acute illness. COVID-19 infection was associated with higher mortality in OHS-suspected patients, independently of actual BMI.

CONCLUSION

Despite the increased risk of obese patients, suspected OHS did not show higher prevalence than expected during the COVID-19 pandemic in critically ill patients. COVID-19 infection however was a risk for mortality in these patients, independent of actual BMI.

Visceral obesity measured using computed tomography scans: No significant association with mortality in critically ill patients

INTRODUCTION

The association between obesity and outcome in critical illness is unclear. Since the amount of visceral adipose tissue(VAT) rather than BMI mediates the health effects of obesity we aimed to investigate the association between visceral obesity, BMI and 90-day mortality in critically ill patients.

METHOD

In 555 critically ill patients (68% male), the VAT Index(VATI) was measured using Computed Tomography scans on the level of vertebra L3. The association between visceral obesity, BMI and 90-day mortality was investigated using univariable and multivariable analyses, correcting for age, sex, APACHE II score, sarcopenia and muscle quality.

RESULTS

Visceral obesity was present in 48.1% of the patients and its prevalence was similar in males and females. Mortality was similar amongst patients with and without visceral obesity (27.7% vs 24.0%, p = 0.31). The corrected odds ratio of 90-day mortality for visceral obesity was 0.667 (95%CI 0.424-1.049, p = 0.080). Using normal BMI as reference, the corrected odds ratio for overweight was 0.721 (95%CI 0.447-1.164 p = 0.181) and for obesity 0.462 (95%CI 0.208-1.027, p = 0.058).

CONCLUSION

No significant association of visceral obesity and BMI with 90-day mortality was observed in critically ill patients, although obesity and visceral obesity tended to be associated with improved 90-day mortality.

Management of Acute Exacerbations of Chronic Obstructive Pulmonary Disease in the ICU: An Observational Study From the OUTCOMEREA Database, 1997-2018

OBJECTIVES

Our aim was to describe changes in the management of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) by ICUs and patient outcomes.

DESIGN

We extracted data from the OutcomeRea database concerning patients admitted for AECOPD between 1997 and 2018. We analyzed trends in the use of ventilatory support, corticosteroid therapy, antibiotic therapy, and patient survival.

SETTING

ICUs at 32 French sites.

PATIENTS

One thousand eight hundred sixteen patients in the database had a diagnosis of AECOPD.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Over time, there was a reduction in the prescription of corticosteroids and antibiotics. In a time-series analysis, these changes in practice were not linked with ICU mortality. The proportion of patients treated with invasive mechanical ventilation (IMV) also gradually declined (from 51% between 1997 and 2002 to 35% between 2013 and 2018) with an association between decrease in IMV use and reduction in ICU mortality in a time series analysis. Rates of noninvasive ventilation (NIV) failure decreased with an increase in NIV use to support weaning from IMV. There was a reduction in the median ICU length of stay (from 8 d in 1997-2002 to 4 d in 2013-2018) and in the median total duration of hospitalization (from 23 d in 1997-2002 to 14 d in 2013-2018). We observed an improvement in prognosis, with decreases in overall hospital mortality (from 24% between 1997 and 2002 to 15% between 2013 and 2018), ICU mortality (from 14% between 1997 and 2002 to 10% between 2013 and 2018), and 90-day mortality (from 41% between 1997 and 2002 to 22% between 2013 and 2018).

CONCLUSIONS

The length of stay and mortality of patients with AECOPD admitted to ICUs has decreased over the last 20 years, with a wider use of NIV and a reduction in antibiotic and corticosteroid prescriptions.

Endocrine Disorders and COVID-19

The multifaceted interaction between coronavirus disease 2019 (COVID-19) and the endocrine system has been a major area of scientific research over the past two years. While common endocrine/metabolic disorders such as obesity and diabetes have been recognized among significant risk factors for COVID-19 severity, several endocrine organs were identified to be targeted by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). New-onset endocrine disorders related to COVID-19 were reported while long-term effects, if any, are yet to be determined. Meanwhile, the "stay home" measures during the pandemic caused interruption in the care of patients with pre-existing endocrine disorders and may have impeded the diagnosis and treatment of new ones. This review aims to outline this complex interaction between COVID-19 and endocrine disorders by synthesizing the current scientific knowledge obtained from clinical and pathophysiological studies, and to emphasize considerations for future research.

Age-adjusted Charlson Comorbidity Index as effective predictor for in-hospital mortality of patients with cardiac arrest: a retrospective study

BACKGROUND

Cardiac arrest is currently one of the leading causes of mortality in clinical practice, and the Charlson Comorbidity Index (CCI) is widely utilized to assess the severity of comorbidities. We aimed to evaluate the relationship between the age-adjusted CCI score and in-hospital mortality in intensive care unit (ICU) patients with the diagnosis of cardiac arrest, which is important but less explored previously.

METHODS

This was a retrospective study including patients aged over 18 years from the MIMIC-IV database. We calculated the age-adjusted CCI using age information and ICD codes. The univariate analysis for varied predictors' differences between the survival and the non-survival groups was performed. In addition, a multiple factor analysis was conducted based on logistic regression analysis with the primary result set as hospitalization death. An additional multivariate regression analysis was conducted to estimate the influence of hospital and ICU stay.

RESULTS

A total of 1772 patients were included in our study, with median age of 66, among which 705 (39.8%) were female. Amongst these patients, 963 (54.3%) died during the hospitalization period. Patients with higher age-adjusted CCI scores had a higher likelihood of dying during hospitalization (P < 0.001; OR: 1.109; 95% CI: 1.068-1.151). With the age-adjusted CCI incorporated into the predictive model, the area under the receiver operating characteristic curve was 0.794 (CI: 0.773-0.814), showing that the prediction model is effective. Additionally, patients with higher age-adjusted CCI scores stayed longer in the hospital (P = 0.026, 95% CI: 0.056-0.896), but there was no significant difference between patients with varied age-adjusted CCI scores on the days of ICU stay.

CONCLUSION

The age-adjusted CCI is a valid indicator to predict death in ICU patients with cardiac arrest, which can offer enlightenment for both theory literatures and clinical practice.

A nomogram for predicting the mortality of patients with type 2 diabetes mellitus complicated with acute kidney injury in the intensive care unit

BACKGROUND

There is no predictive tool for type 2 diabetes mellitus (T2DM) patients with acute kidney injury (AKI). Our study aimed to establish an effective nomogram model for predicting mortality in T2DM patients with AKI.

METHOD

Data on T2DM patients with AKI were obtained from the Medical Information Mart for Intensive Care III. 70% and 30% of the patients were randomly selected as the training and validation cohorts, respectively. Univariate and multivariate logistic regression analyses were used to identify factors associated with death in T2DM patients with AKI. Factors significantly associated with survival outcomes were used to construct a nomogram predicting 90-day mortality. The nomogram effect was evaluated by receiver operating characteristic curve analysis, Hosmer‒Lemeshow test, calibration curve, and decision curve analysis (DCA).

RESULTS

There were 4375 patients in the training cohort and 1879 in the validation cohort. Multivariate logistic regression analysis showed that age, BMI, chronic heart failure, coronary artery disease, malignancy, stages of AKI, white blood cell count, blood urea nitrogen, arterial partial pressure of oxygen and partial thromboplastin time were independent predictors of patient survival. The results showed that the nomogram had a higher area under the curve value than the sequential organ failure assessment score and simplified acute physiology score II. The Hosmer‒Lemeshow test and calibration curve suggested that the nomogram had a good calibration effect. The DCA curve showed that the nomogram model had good clinical application value.

CONCLUSION

The nomogram model accurately predicted 90-day mortality in T2DM patients with AKI. It may provide assistance for clinical decision-making and treatment, thereby reducing the medical burden.

Impact of BMI on outcomes in respiratory ECMO: an ELSO registry study

PURPOSE

The impact of body mass index (BMI) on outcomes in respiratory failure necessitating extracorporeal membrane oxygenation (ECMO) has been poorly described. We aimed to assess: (i) whether adults with class II obesity or more (BMI ≥ 35 kg/m²) have worse outcomes than lean counterparts, (ii) the form of the relationship between BMI and outcomes, (iii) whether a cutoff marking futility can be identified.

METHODS

A retrospective analysis of the Extracorporeal Life Support Organization (ELSO) Registry from 1/1/2010 to 31/12/2020 was conducted. Impact of BMI ≥ 35 kg/m² was assessed with propensity-score (PS) matching, inverse propensity-score weighted (IPSW) and multivariable models (MV), adjusting for a priori identified confounders. Primary outcome was in-hospital mortality. The form of the relationship between BMI and outcomes was studied with generalized additive models. Outcomes across World Health Organisation (WHO)-defined BMI categories were compared.

RESULTS

Among 18,529 patients, BMI ≥ 35 kg/m² was consistently associated with reduced in-hospital mortality [PS-matched: OR: 0.878(95%CI 0.798-0.966), p = 0.008; IPSW: OR: 0.899(95%CI 0.827-0.979), p = 0.014; MV: OR: 0.900(95%CI 0.834-0.971), p = 0.007] and shorter hospital length of stays. In patients with BMI ≥ 35 kg/m², cardiovascular (17.3% versus 15.3%), renal (37% versus 30%) and device-related complications (25.7% versus 20.6%) increased, whereas pulmonary complications decreased (7.6% versus 9.3%). These findings were independent of confounders throughout PS-matched, IPSW and MV models. The relationship between BMI and outcomes was non-linear and no cutoff for futility was identified.

CONCLUSION

Patients with obesity class II or more treated with ECMO for respiratory failure have lower mortality risk and shorter stays, despite increased cardiovascular, device-related, and renal complications. No upper limit of BMI indicating futility of ECMO treatment could be identified. BMI as single parameter should not be a contra-indication for respiratory ECMO.

Impact of obesity on all-cause and cause-specific mortality among critically ill men and women: a cohort study on the eICU database

Background

The effect of obesity on intensive care unit outcomes among critically ill patients and whether there are sex differences have not been well investigated. We sought to determine the association between obesity and 30-day all-cause and cause-specific mortality among critically ill men and women.

Methods

Adult participants who had body mass index (BMI) measurements were included from the eICU database. Participants were divided into six groups according to BMI (kg/m²) categories (underweight, <18.5; normal weight, 18.5-24.9; overweight, 25-29.9; class I obesity, 30-34.9; class II obesity, 35-39.9; class III obesity, ≥40). A multivariable adjusted logistic model was conducted with odds ratios (ORs) and 95% confidence intervals (CIs). A cubic spline curve based on the generalized additive model was used to represent the nonlinear association. Stratified analysis and sensitivity analysis were also performed.

Results

A total of 160,940 individuals were included in the analysis. Compared with the class I obesity category, the underweight and normal weight categories had higher all-cause mortality, and the multivariable adjusted ORs were 1.62 (95% CI: 1.48-1.77) and 1.20 (95% CI: 1.13-1.27) for the general population, 1.76 (95% CI: 1.54-2.01) and 1.22 (95% CI: 1.13-1.32) for men, and 1.51 (95% CI: 1.33-1.71) and 1.16 (95% CI: 1.06-1.27) for women, respectively. Accordingly, multivariable adjusted ORs for the class III obesity category were 1.14 (95% CI: 1.05-1.24) for the general population, 1.18 (95% CI: 1.05-1.33) for men, and 1.10 (95% CI: 0.98-1.23) for women. With cubic spline curves, the association between BMI and all-cause mortality was U-shaped or reverse J-shaped. Similar findings were observed for cause-specific mortality, with the underweight category associated with a higher risk of mortality. Class III obesity increased the risk of cardiovascular death among men (OR 1.51; 95% CI: 1.23-1.84) and increased the risk of other-cause death among women (OR 1.33; 95% CI: 1.10-1.61).

Conclusion

The obesity paradox appears to be suitable for all-cause and cause-specific mortality among critically ill men and women. However, the protective effect of obesity cannot be extended to severely obese individuals. The association between BMI and cardiovascular mortality was sex-specific and was more pronounced among men than among women. Graphical abstract.

The effect of positive end-expiratory pressure on intracranial pressure in obese and non-obese severe brain injury patients: a retrospective observational study

BACKGROUND

The effect of positive end-expiratory pressure (PEEP) on intracranial pressure (ICP) had never been studied in obese patients with severe brain injury (SBI). The main aim was to evaluate the effect of PEEP on ICP in SBI patients with mechanical ventilation according to obesity status.

METHODS

SBI patients admitted to the ICU with mechanical ventilation between 2014 and 2015 were included. Demographic, hemodynamic, arterial blood gas, and ventilator data at the time of the paired PEEP and ICP observations were recorded and compared between obese (body mass index ≥ 30 kg/m²) and non-obese SBI patients. Generalized estimating equation (GEE) model was used to assess the relationship between PEEP and ICP in obese and non-obese SBI patients, respectively.

RESULTS

Six hundred twenty-seven SBI patients were included, 407 (65%) non-obese and 220 (35%) obese patients. A total of 30,415 paired PEEP and ICP observations were recorded in these patients, 19,566 (64.3%) for non-obese and 10,849 (35.7%) for obese. In the multivariable analysis, a statistically significant relationship between PEEP and ICP was found in obese SBI patients, but not in non-obese ones. For every cmH₂O increase in PEEP, there was a 0.19 mmHg increase in ICP (95% CI [0.05, 0.33], P = 0.007) and a 0.15 mmHg decrease in CPP (95% CI [-0.29, -0.01], P = 0.036) in obese SBI patients after adjusting for confounders.

CONCLUSIONS

The results suggested that, contrary to non-obese SBI patients, the application of PEEP may produce an increase in ICP in obese SBI patients. However, the effect was modest and may be clinically inconsequential.

Machine learning-derived prediction of in-hospital mortality in patients with severe acute respiratory infection: analysis of claims data from the German-wide Helios hospital network

BACKGROUND

Severe acute respiratory infections (SARI) are the most common infectious causes of death. Previous work regarding mortality prediction models for SARI using machine learning (ML) algorithms that can be useful for both individual risk stratification and quality of care assessment is scarce. We aimed to develop reliable models for mortality prediction in SARI patients utilizing ML algorithms and compare its performances with a classic regression analysis approach.

METHODS

Administrative data (dataset randomly split 75%/25% for model training/testing) from years 2016-2019 of 86 German Helios hospitals was retrospectively analyzed. Inpatient SARI cases were defined by ICD-codes J09-J22. Three ML algorithms were evaluated and its performance compared to generalized linear models (GLM) by computing receiver operating characteristic area under the curve (AUC) and area under the precision-recall curve (AUPRC).

RESULTS

The dataset contained 241,988 inpatient SARI cases (75 years or older: 49%; male 56.2%). In-hospital mortality was 11.6%. AUC and AUPRC in the testing dataset were 0.83 and 0.372 for GLM, 0.831 and 0.384 for random forest (RF), 0.834 and 0.382 for single layer neural network (NNET) and 0.834 and 0.389 for extreme gradient boosting (XGBoost). Statistical comparison of ROC AUCs revealed a better performance of NNET and XGBoost as compared to GLM.

CONCLUSION

ML algorithms for predicting in-hospital mortality were trained and tested on a large real-world administrative dataset of SARI patients and showed good discriminatory performances. Broad application of our models in clinical routine practice can contribute to patients' risk assessment and quality management.

A nomogram to predict prolonged stay of obesity patients with sepsis in ICU: Relevancy for predictive, personalized, preventive, and participatory healthcare strategies

Objective

In an era of increasingly expensive intensive care costs, it is essential to evaluate early whether the length of stay (LOS) in the intensive care unit (ICU) of obesity patients with sepsis will be prolonged. On the one hand, it can reduce costs; on the other hand, it can reduce nosocomial infection. Therefore, this study aimed to verify whether ICU prolonged LOS was significantly associated with poor prognosis poor in obesity patients with sepsis and develop a simple prediction model to personalize the risk of ICU prolonged LOS for obesity patients with sepsis.

Method

In total, 14,483 patients from the eICU Collaborative Research Database were randomized to the training set (3,606 patients) and validation set (1,600 patients). The potential predictors of ICU prolonged LOS among various factors were identified using logistic regression analysis. For internal and external validation, a nomogram was developed and performed.

Results

ICU prolonged LOS was defined as the third quartile of ICU LOS or more for all sepsis patients and demonstrated to be significantly associated with the mortality in ICU by logistic regression analysis. When entering the ICU, seven independent risk factors were identified: maximum white blood cell, minimum white blood cell, use of ventilation, Glasgow Coma Scale, minimum albumin, maximum respiratory rate, and minimum red blood cell distribution width. In the internal validation set, the area under the curve was 0.73, while in the external validation set, it was 0.78. The calibration curves showed that this model predicted probability due to actually observed probability. Furthermore, the decision curve analysis and clinical impact curve showed that the nomogram had a high clinical net benefit.

Conclusion

In obesity patients with sepsis, we created a novel nomogram to predict the risk of ICU prolonged LOS. This prediction model is accurate and reliable, and it can assist patients and clinicians in determining prognosis and making clinical decisions.

One-Year Follow-Up of Patients Admitted for Emergency Coronary Angiography after Resuscitated Cardiac Arrest

(1) Background: Despite the improvement of the in-hospital survival rate after aborted sudden cardiac death (SCD), cerebral anoxia may have severe neurologic consequences and may impair long-term outcome and quality of life of surviving patients. The aim of this study was to assess neurological outcomes at one year after resuscitated cardiac arrest; (2) Methods: This prospective, observational, and multicentre study included patients >18 yo admitted in the catheterisation laboratory for coronary angiography after aborted SCD between 1 May 2018 and 31 May 2020. Only patients who were discharged alive from hospital were evaluated. The primary endpoint was survival without neurological sequelae at one-year follow-up defined by a cerebral performance category (CPC) of one or two. Secondary end points included all-cause mortality, New York Heart Association (NYHA) functional class, neurologic evaluation at discharge, three-month and one-year follow-up using the CPC scale, and quality of life at 1 year using the Quality of Life after Brain Injury (QOLIBRI) questionnaire; (3) Results: Among 143 patients admitted for SCD within the study period, 61 (42.7%) were discharged alive from hospital, among whom 55 (90.1%) completed the one-year follow-up. No flow and low flow times were 1.9 ± 2.4 min and 16.5 ± 10.4 min, respectively. For 93.4% of the surviving patients, an initial shockable rhythm (n = 57) was observed and acute coronary syndrome was diagnosed in 75.4% of them (n = 46). At 1 year, survival rate without neurologic sequelae was 87.2% (n = 48). Patients with poor outcome were older (69.3 vs. 57.4 yo; p = 0.04) and had lower body mass index (22.4 vs. 26.7; p = 0.013) and a lower initial Left Ventricle Ejection Fraction (LVEF) (32.1% vs. 40.3%; p = 0.046). During follow-up, neurological status improved in 36.8% of patients presenting sequelae at discharge, and overall quality of life was satisfying for 66.7% of patients according to the QOLIBRI questionnaire; (4) Conclusions: Among patients admitted to the catheterisation laboratory for aborted SCD, mainly related to Acute Coronary Syndrom (ACS), less than a half of them were alive at discharge. However, the one-year survival rate without neurological sequelae was high and overall quality of life was good.

Methodological Rigor and Transparency in Clinical Practice Guidelines for Nutrition Care in Critically Ill Adults: A Systematic Review Using the AGREE II and AGREE-REX Tools

Background: To evaluate the methodological quality of (1) clinical practice guidelines (CPGs) that inform nutrition care in critically ill adults using the AGREE II tool and (2) CPG recommendations for determining energy expenditure using the AGREE-REX tool. Methods: CPGs by a professional society or academic group, intended to guide nutrition care in critically ill adults, that used a systematic literature search and rated the evidence were included. Four databases and grey literature were searched from January 2011 to 19 January 2022. Five investigators assessed the methodological quality of CPGs and recommendations specific to energy expenditure determination. Scaled domain scores were calculated for AGREE II and a scaled total score for AGREE-REX. Data are presented as medians (interquartile range). Results: Eleven CPGs were included. Highest scoring domains for AGREE II were clarity of presentation (82% [76–87%]) and scope and purpose (78% [66–83%]). Lowest scoring domains were applicability (37% [32–42%]) and stakeholder involvement (46% [33–51%]). Eight (73%) CPGs provided recommendations relating to energy expenditure determination; scores were low overall (37% [36–40%]) and across individual domains. Conclusions: Nutrition CPGs for critically ill patients are developed using systematic methods but lack engagement with key stakeholders and guidance to support application. The quality of energy expenditure determination recommendations is low.

Adipose-Derived Circulating Exosomes Promote Protection of the Pulmonary Endothelial Barrier by Inhibiting EndMT and Oxidative Stress through Down-Regulation of the TGF-β Pathway: A Potential Explanation for the Obesity Paradox in ARDS

The “obesity paradox in acute respiratory distress syndrome” (ARDS) refers to the phenomenon in which obesity is associated with higher morbidity but lower mortality in patients with ARDS. Endothelial-to-mesenchymal transition (EndMT) represents a key link in the interaction between endothelial disruption and mesenchymal fibrosis under inflammatory and oxidative conditions, which represent the intersectional pathophysiology of ARDS. Adipose tissue is considered to constitute the major source of circulating exosomal microRNAs (miRNAs), which act as genetic forms of adipokines for cell–cell crosstalk. We aimed to demonstrate the regulation and mechanism of adipose-derived exosomes in the obesity paradox in ARDS. High-fat-induced obese mice and lean control mice were subjected to ARDS insult to investigate the effects of obesity on ARDS and microarray analysis was performed to screen for differences in circulating miRNAs. In addition, mice and pulmonary endothelial cells were administered with adipose-derived exosomal miR-122-5p to investigate the underlying molecular mechanisms. We found high-fat diet-induced obesity protected against ARDS in mice by reinforcing endothelial barrier and attenuating fibroproliferation. Circulating exosomes produced in the obese state mediated these protective effects by inhibiting EndMT and oxidative stress. Mechanistically, adipose-derived exosomal miR-122-5p promoted the integrity and function of pulmonary endothelial barrier and alleviated fibrogenesis by suppressing EndMT and oxidative stress through down-regulation of the transforming growth factor β1 (TGF-β1)/TGF-β receptor 1 (TGF-βR1)/Smad2 pathway in vivo and in vitro. In conclusion, adipose-derived circulating exosomal miR-122-5p protects against ARDS by reinforcing pulmonary endothelial barrier through inhibition of EndMT and oxidative stress via down-regulation of the TGF-β pathway, which propose a potential explanation for the obesity paradox in ARDS and indicate promising prospects for adipose-derived exosomes in cell-free therapies for ARDS.

Impact of Oxygen Saturation on Mortality in Obese and Non-obese Critically Ill Patients With Mechanical Ventilation: A Retrospective Observational Study

Background

The main aim of this study was to evaluate the effect of oxygen saturation on mortality in critically ill patients with mechanical ventilation according to obesity status.

Methods

We conducted an observational study in mechanically ventilated patients admitted to the ICU retrospectively. Demographic, arterial blood gas, ventilator setting, interventions, and peripheral oxygen saturation (Spo₂) during the first 24 h were recorded and analyzed between non-obese and obese patients. The main exposure included Spo₂, time-weighted mean Spo₂ (TWM-Spo₂), and proportion of time spent in different Spo₂ (PTS-Spo₂) levels. The primary outcome was hospital mortality. We used multivariable logistic regression models to assess the relationship between Spo₂ and mortality, as well as the interaction between PTS-Spo₂ and obesity status.

Results

A total of 25,100 patients were included, of which 10,564 (42%) were obese patients. After adjusting for confounders, compared with TWM-Spo₂ of 94–98%, TWM-Spo₂ of < =88% (OR 3.572; CI [2.343, 5.455]; p < 0.001) and of 89–93% (OR 1.514; CI [1.343, 1.706]; p < 0.001) were both associated with higher risk of mortality. PTS-Spo₂ of 99–100% was associated with increased risk of mortality for obese patients (OR 1.028; 95% CI 1.010–1.046; p = 0.002; P_{interaction =} 0.001), while PTS-Spo₂ of 89–93% was associated with increased risk of mortality (OR 1.089; 95% CI 1.051–1.128; p < 0.001; P_{interaction =} 0.001) for non-obese patients.

Conclusions

For obese and non-obese critically ill patients with mechanical ventilation, the impact of oxygen saturation on hospital mortality is different.

Differences in early, intermediate, and long-term mortality among elderly patients admitted to the ICU. Results of a retrospective observational study

BACKGROUND

Few studies have investigated both short- and long-term prognostic factors, and the differences between chronic and acute conditions in the very old critically-ill patient. Our study aims to shed light in this field and to provide useful prognostic factors that may support clinical decisions in the management of the elderly.

METHODS

Six ICUs collected data concerning patients 80 years old or more admitted in 2015 and 2016 and followed-up until may 2018. Three prognostic models were developed: an in-hospital mortality model, a model for patients discharged from the hospital and entering follow-up, and an intermediate model for those alive after three days from ICU admission.

RESULTS

Our centers admitted 1189 patients, 1071 (90.1%) had survived after three days from admission, 889 (74.8%) were discharged from the hospital, 701 (59.0%) survived six months after hospital discharge, 539 (45.3%) survived at the end of follow-up. Among survivors the median follow-up time was 810 days. Acute organ failures were the main causes of death in the hospital mortality multivariable model. These factors are modifiable and potentially a target for intervention to improve outcome. The model focused on mortality six months after hospital in patients that survived a three-day timelimited trial, showed a clear shift toward chronic diseases, unmodifiable factors crucial for prognostic assessment. This trend was even more evident at the end of follow-up.

CONCLUSIONS

Among very old ICU patients, prognostic factors shift from acute to chronic conditions in passing from in-hospital to post-hospital outcomes.

The impact of obesity on outcomes of patients admitted to intensive care after cardiac arrest

PURPOSE

Studies examining the association between obesity and mortality in cardiac arrest patients have been conflicting which might either be due to residual confounding, or a reliance on estimating the conditional effects rather than the marginal (causal) effects of obesity. We estimated the conditional and causal effects of obesity on mortality in cardiac arrest patients using the Australian and New Zealand Intensive Care Society (ANZICS) Adult Patient Database (APD).

MATERIALS AND METHODS

This retrospective registry-based cohort study from ICUs of Australia and New Zealand included all ICU patients admitted with cardiac arrest between 2010 and 2020 with height and weight data recorded. The conditional and marginal effects of obesity on mortality was estimated using multivariate binary logistic regression and Targeted Maximum Likelihood Estimation (TMLE) respectively. The primary outcome was in-hospital mortality.

RESULTS

A total 13,970 patients had complete data and were available for analysis. In multivariate binary logistic regression, there was no difference in the odds of in-hospital mortality for the obese versus non-obese groups; adjusted OR = 0.95, 95% CI = 0.87-1.03; p 0.25. Results were similar using TMLE (Marginal OR= 0.97; 95% CI = 0.91-1.02, p = 0.62).

CONCLUSION

After adjustment, there was no association between obesity and outcomes in cardiac arrest patients admitted to ICU.

The Impact of Obesity on Sudden Cardiac Death Risk

PURPOSE OF REVIEW

We aimed to describe the epidemiology of sudden cardiac death (SCD) in the obese, elaborating on the potential pathophysiological mechanisms linking obesity, SCD, and the outcomes in SCD survivors, as well as looking into the intriguing "obesity paradox" in these patients.

RECENT FINDINGS

Several studies show increased mortality in patients with BMI > 30 kg/m² admitted to the hospital following SCD. At the same time, other studies have implied that the "obesity paradox," described in various cardiovascular conditions, applies to patients admitted after SCD, showing lower mortality in the obese compared to normal weight and underweight patients. We found a significant body of evidence to support that while obesity increases the risk for SCD, the outcomes of obese patients post SCD are better. These findings should not be interpreted as supporting weight gain, as it is always better to prevent the "disaster" from happening than to improve your chances of surviving it. Obesity is shown to be significantly associated with increased risk for SCD; however, there is a growing body of evidence, supporting the "obesity paradox" in the survival of SCD victims. Prospectively, well-designed studies are needed to confirm these findings.

Obesity attenuates inflammation, protein catabolism, dyslipidaemia, and muscle weakness during sepsis, independent of leptin

BACKGROUND

Muscle weakness is a frequently occurring complication of sepsis, associated with increased morbidity and mortality. Interestingly, obesity attenuates sepsis-induced muscle wasting and weakness. As the adipokine leptin is strongly elevated in obesity and has been shown to affect muscle homeostasis in non-septic conditions, we aimed to investigate whether leptin mediates the protective effect of obesity on sepsis-induced muscle weakness.

METHODS

In a mouse model of sepsis, we investigated the effects of genetic leptin inactivation in obese mice (leptin-deficient obese mice vs. diet-induced obese mice) and of leptin supplementation in lean mice (n = 110). We assessed impact on survival, body weight and composition, markers of muscle wasting and weakness, inflammation, and lipid metabolism. In human lean and overweight/obese intensive care unit (ICU) patients, we assessed markers of protein catabolism (n = 1388) and serum leptin (n = 150).

RESULTS

Sepsis mortality was highest in leptin-deficient obese mice (53% vs. 23% in diet-induced obese mice and 37% in lean mice, P = 0.03). Irrespective of leptin, after 5 days of sepsis, lean mice lost double the amount of lean body mass than obese mice (P < 0.0005). Also, irrespective of leptin, obese mice maintained specific muscle force up to healthy levels (P = 0.3) whereas lean mice suffered from reduced specific muscle force (72% of healthy controls, P < 0.0002). As compared with lean septic mice, both obese septic groups had less muscle atrophy, liver amino acid catabolism, and inflammation with a 50% lower plasma TNFα increase (P < 0.005). Conversely, again mainly irrespective of leptin, obese mice lost double amount of fat mass than lean mice after 5 days of sepsis (P < 0.0001), showed signs of increased lipolysis and ketogenesis, and had higher plasma HDL and LDL lipoprotein concentrations (P ≤ 0.01 for all). Muscle fibre type composition was not altered during sepsis, but a higher atrophy sensitivity of type IIb fibres compared with IIa and IIx fibres was observed, independent of obesity or leptin. After 5 days of critical illness, serum leptin was higher (P < 0.0001) and the net waste of nitrogen (P = 0.006) and plasma urea-to-creatinine ratio (P < 0.0001) was lower in overweight/obese compared with lean ICU human patients.

CONCLUSIONS

Leptin did not mediate the protective effect of obesity against sepsis-induced muscle wasting and weakness in mice. Instead, obesity-independent of leptin-attenuated inflammation, protein catabolism, and dyslipidaemia, pathways that may play a role in the observed muscle protection.

Obesity paradox in patients with chronic total occlusion of coronary artery

BACKGROUND

Obesity is associated with metabolic syndrome which increases further risk of coronary artery disease and adverse cardiovascular events. Impact of body mass index (BMI) on long-term outcome in patients with coronary chronic total occlusion (CTO) is less clear.

METHOD AND RESULTS

From January 2005 to November 2020, a total of 1301 patients with coronary angiographic confirmed CTO were enrolled in our study. Patients were divided into two groups: low BMI group: 18-24.99 kg/m² and high BMI group ≥25 kg/m² . Clinical outcomes were 3-year all-cause mortality, 3-year cardiovascular mortality and 3-year non-fatal myocardial infarct. During the 3-year follow-up period, all-cause mortality was significantly higher in patients with low BMI group compared to those in high BMI groups (14% vs. 6%, p = .0001). Kaplan-Meier analysis showed patients with high BMI groups had significant better survival compared with those in low BMI group (p = .0001). In multivariate analysis, higher BMI was independently associated with decreased risk of 3-year all-cause mortality (Hazard ratio [HR]: 0.534; 95% confidence interval [CI]: 0.349-0.819, p = .004) after controlling for age, renal function, prior history of stroke, coronary artery bypass graft, co-morbidities with peripheral arterial disease, heart failure and revascularization status for CTO. In propensity-matched multivariate analysis, high BMI remained a significant predictor of 3-year all-cause mortality (HR, 0.525; 95% CI, 0.346-0.795, p = .002).

CONCLUSION

Higher BMI was associated with better long-term outcome in patients with coronary CTO.

A Simple Weaning Model Based on Interpretable Machine Learning Algorithm for Patients With Sepsis: A Research of MIMIC-IV and eICU Databases

Background

Invasive mechanical ventilation plays an important role in the prognosis of patients with sepsis. However, there are, currently, no tools specifically designed to assess weaning from invasive mechanical ventilation in patients with sepsis. The aim of our study was to develop a practical model to predict weaning in patients with sepsis.

Methods

We extracted patient information from the Medical Information Mart for Intensive Care Database-IV (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD). Kaplan–Meier curves were plotted to compare the 28-day mortality between patients who successfully weaned and those who failed to wean. Subsequently, MIMIC-IV was divided into a training set and an internal verification set, and the eICU-CRD was designated as the external verification set. We selected the best model to simplify the internal and external validation sets based on the performance of the model.

Results

A total of 5020 and 7081 sepsis patients with invasive mechanical ventilation in MIMIC-IV and eICU-CRD were included, respectively. After matching, weaning was independently associated with 28-day mortality and length of ICU stay (p &lt; 0.001 and p = 0.002, respectively). After comparison, 35 clinical variables were extracted to build weaning models. XGBoost performed the best discrimination among the models in the internal and external validation sets (AUROC: 0.80 and 0.86, respectively). Finally, a simplified model was developed based on XGBoost, which included only four variables. The simplified model also had good predictive performance (AUROC:0.75 and 0.78 in internal and external validation sets, respectively) and was developed into a web-based tool for further review.

Conclusions

Weaning success is independently related to short-term mortality in patients with sepsis. The simplified model based on the XGBoost algorithm provides good predictive performance and great clinical applicablity for weaning, and a web-based tool was developed for better clinical application.

Emergencies in obese patients: a narrative review

Obesity is associated to an increased risk of morbidity and mortality due to respiratory, cardiovascular, metabolic, and neoplastic diseases. The aim of this narrative review is to assess the physio-pathological characteristics of obese patients and how they influence the clinical approach during different emergency settings, including cardiopulmonary resuscitation. A literature search for published manuscripts regarding emergency and obesity across MEDLINE, EMBASE, and Cochrane Central was performed including records till January 1, 2021. Increasing incidence of obesity causes growth in emergency maneuvers dealing with airway management, vascular accesses, and drug treatment due to both pharmacokinetic and pharmacodynamic alterations. Furthermore, instrumental diagnostics and in/out-hospital transport may represent further pitfalls. Therefore, people with severe obesity may be seriously disadvantaged in emergency health care settings, and this condition is enhanced during the COVID-19 pandemic, when obesity was stated as one of the most frequent comorbidity. Emergency in critical obese patients turns out to be an intellectual, procedural, and technical challenge. Organization and anticipation based on the understanding of the physiopathology related to obesity are very important for the physician to be mentally and physically ready to face the associated issues.

A retrospective case-control cohort analysis of comorbidity and health expenditure in hospitalized adults diagnosed with obesity utilizing ICD-10 diagnostic coding

The cost and comorbidity of obesity in hospitalized inpatients, is less known. A retrospective study of patients presenting to a large district hospital in Western Sydney (April 2016-February 2017) using clinical, pathological as well as diagnostic coding data for obesity as per ICD-10. Of 43 212 consecutive hospital presentations, 390 had an obesity-coded diagnosis (Ob, 0.90%), of which 244 were gender and age-matched to a non-obesity coded cohort (NOb). Weight and BMI were higher in the Ob vs NOb group (126 ± 37 vs 82 ± 25 kg; BMI 46 ± 12 vs 29 ± 8 kg/m² , P < .001) with a medical record documentation rate of 62% for obesity among Ob. The Ob cohort had 2-5× higher rates of cardiopulmonary and metabolic complications (P < .001), greater pharmacologic burden, length of stay (LOS, 225 vs 89 hours, P < .001) and stay in intensive care but no differences in the prevalence of mental disorders. Compared with BMI <35 kg/m² , inpatients with BMI >35 kg/m² were 5× more likely to require intensive care (OR 5.08 [1.43-27.3, 95% CI], P = .0047). The initiation of obesity-specific interventions by clinical teams was very low. People with obesity who are admitted to hospital carry significant cost and complications, yet obesity is seldom recognized as a clinical entity or contributor.

Secreted Extracellular Cyclophilin A Is a Novel Mediator of Ventilator-induced Lung Injury

Rationale: Mechanical ventilation is a mainstay of intensive care but contributes to the mortality of patients through ventilator-induced lung injury. eCypA (extracellular CypA [cyclophilin A]) is an emerging inflammatory mediator and metalloproteinase inducer, and the gene responsible for its expression has recently been linked to coronavirus disease (COVID-19). Objectives: To explore the involvement of eCypA in the pathophysiology of ventilator-induced lung injury. Methods: Mice were ventilated with a low or high Vt for up to 3 hours, with or without blockade of eCypA signaling, and lung injury and inflammation were evaluated. Human primary alveolar epithelial cells were exposed to in vitro stretching to explore the cellular source of eCypA, and CypA concentrations were measured in BAL fluid from patients with acute respiratory distress syndrome to evaluate the clinical relevance. Measurements and Main Results: High-Vt ventilation in mice provoked a rapid increase in soluble CypA concentration in the alveolar space but not in plasma. In vivo ventilation and in vitro stretching experiments indicated the alveolar epithelium as the likely major source. In vivo blockade of eCypA signaling substantially attenuated physiological dysfunction, macrophage activation, and MMPs (matrix metalloproteinases). Finally, we found that patients with acute respiratory distress syndrome showed markedly elevated concentrations of eCypA within BAL fluid. Conclusions: CypA is upregulated within the lungs of injuriously ventilated mice (and critically ill patients), where it plays a significant role in lung injury. eCypA represents an exciting novel target for pharmacological intervention.

Association between body mass index and short-term mortality in patients with intra-abdominal infections: a retrospective, single-centre cohort study using the Medical Information Mart for Intensive Care database

OBJECTIVES

This study aimed to determine the relationship between the body mass index (BMI) and short-term mortality of patients with intra-abdominal infection (IAI) using the Medical Information Mart for Intensive Care (MIMIC-III) database.

DESIGN

Retrospective cohort study.

SETTING

Adult intensive care units (ICUs) at a tertiary hospital in the USA .

PARTICIPANTS

Adult IAI ICU patients from 2001 to 2012 in the MIMIC-III database.

INTERVENTIONS

In univariate analysis, we compared the differences in the characteristics of patients in each BMI group. Cox regression models were used to evaluate the relationships between BMI and short-term prognosis.

PRIMARY AND SECONDARY OUTCOME MEASURES

90-day survival.

RESULTS

In total, 1161 patients with IAI were included. There were 399 (34.4%) patients with a normal BMI (<25 kg/m²), 357 (30.8%) overweight patients (25-30 kg/m²) and 405 (34.9%) obese patients (>30 kg/m²) who tended to be younger (p<0.001) and had higher Sequential Organ Failure Assessment scores (p<0.05). The mortality of obese patients at 90 days was lower than that of patients with a normal BMI (20.74% vs 23.25%, p<0.05), but their length of stay in the ICU was higher (4.9 days vs 3.6 days, p<0.001); however, their rate of mechanical ventilation utilisation was higher (61.48% vs 56.86%, p<0.05). In the Cox regression model, we also confirmed that BMI was a protective factor in patients with IAIs, and the adjusted mortality rate of patients with a higher BMI was 0.97 times lower than that of patients with a lower BMI (p<0.001, HR=0.97, 95% CI 0.96 to 0.99).

CONCLUSIONS

IAI patients with an overweight or obese status might have lower 90-day mortality than patients with a normal BMI.

Prognostic value of preoperative body mass index for diabetic patients with non-metastasis gastric cancer: a single center experience

Aim

This study was designed to investigate the prognostic effect of preoperative body mass index (BMI) for Type 2 diabetes mellitus (T2DM) patients with non-metastasis gastric cancer (GC) who underwent D₂ gastrectomy.

Methods

T2DM patients with pT_1–4bN_0–3bM₀ GC were retrospectively collected in Department of Gastrointestinal Surgical Oncology, Fujian Cancer Hospital & Fujian Medical University Cancer Hospital from January, 2000 to December, 2010. These patients underwent D₂ radical resection of the stomach combined with regional lymphadenectomy. Chi-square test was used to analyze unordered categorical variables and ranked data, followed by Kaplan–Meier analysis as well as Cox regression models to detect risk factors for survival outcomes. In addition, the cut-off point was determined by the X-tile program. All analyses were carried out using survival package of R and SPSS Software.

Results

A total of 302 T2DM patients with pT_1–4bN_0–3bM₀ GC were collected and analyzed. The cut-off points of BMI, identified by the X-tile program, was 19 kg/m². Patients with low BMI (< 19 kg/m²) had a higher percentage of advanced T stage (T_4a and T_4b), more advanced TNM stage (stage IIIA, IIIB and IIIC), and more elevated level of serum carcinoembryonic antigen (CEA), compared to those with high BMI (> 19 kg/m²) (all P < 0.05). In the low BMI subgroup, the 5-year overall survival rate was 39.02%, which was as high as 58.11% in the high BMI subgroup (P < 0.05). In the multivariate Cox regression model revealed that III_C stage (OR = 3.101), N_3b stage (OR = 3.113) were the most important prognostic indicators, followed by pretreatment BMI (OR = 2.136).

Conclusion

Low preoperative BMI (< 19 kg/m²) was a poor prognostic marker for T2DM patients with pT_1–4bN_0–3bM₀ GC.

Association between Advanced Lung Inflammation Index and 30-Day Mortality in Patients with Acute Respiratory Distress Syndrome

Background and objectives: The advanced lung inflammation index (ALI) was developed to assess the degree of systemic inflammation and has an association with prognosis in patients with lung malignancy. The prognostic value of ALI has not yet been evaluated in patients with acute respiratory distress syndrome (ARDS). Materials and Methods: Between January 2014 and May 2018, patients with ARDS in the medical intensive care unit (ICU) were reviewed retrospectively. The ALI value was calculated as the (body mass index × serum albumin level)/neutrophil-lymphocyte ratio. The cut-off value for distinguishing low from high ALI was defined according to receiver-operating characteristic curve analysis. Results: A total of 164 patients were analyzed. Their median age was 73 years, and 73% was male. The main cause of ARDS was pneumonia (95.7%, 157/164). ICU and in-hospital mortality rates were 59.8% (98/164) and 64% (105/164), respectively. The 30 day mortality was 60.9% (100/164). The median ALI value in non-survivors was lower than that in survivors at 30 day (3.81 vs. 7.39, p = 0.005). In multivariate analysis, low ALI value (≤5.38) was associated with increased 30 day mortality (odds ratio, 2.944, confidence interval 1.178–7.355, p = 0.021). Conclusions: A low ALI value was associated with increased 30 day mortality in patients with ARDS.

Sarcopenia as a predictor of mortality among the critically ill in an intensive care unit: a systematic review and meta-analysis

BACKGROUND

The evidence of sarcopenia based on CT-scan as an important prognostic factor for critically ill patients has not seen consistent results. To determine the impact of sarcopenia on mortality in critically ill patients, we performed a systematic review and meta-analysis to quantify the association between sarcopenia and mortality.

METHODS

We searched studies from the literature of PubMed, EMBASE, and Cochrane Library from database inception to June 15, 2020. All observational studies exploring the relationship between sarcopenia based on CT-scan and mortality in critically ill patients were included. The search and data analysis were independently conducted by two investigators. A meta-analysis was performed using STATA Version 14.0 software using a fixed-effects model.

RESULTS

Fourteen studies with a total of 3,249 participants were included in our meta-analysis. The pooled prevalence of sarcopenia among critically ill patients was 41 % (95 % CI:33-49 %). Critically ill patients with sarcopenia in the intensive care unit have an increased risk of mortality compared to critically ill patients without sarcopenia (OR = 2.28, 95 %CI: 1.83-2.83; P < 0.001; I² = 22.1 %). In addition, a subgroup analysis found that sarcopenia was associated with high risk of mortality when defining sarcopenia by total psoas muscle area (TPA, OR = 3.12,95 %CI:1.71-5.70), skeletal muscle index (SMI, OR = 2.16,95 %CI:1.60-2.90), skeletal muscle area (SMA, OR = 2.29, 95 %CI:1.37-3.83), and masseter muscle(OR = 2.08, 95 %CI:1.15-3.77). Furthermore, critically ill patients with sarcopenia have an increased risk of mortality regardless of mortality types such as in-hospital mortality (OR = 1.99, 95 %CI:1.45-2.73), 30-day mortality(OR = 2.08, 95 %CI:1.36-3.19), and 1-year mortality (OR = 3.23, 95 %CI:2.08 -5.00).

CONCLUSIONS

Sarcopenia increases the risk of mortality in critical illness. Identifying the risk factors of sarcopenia should be routine in clinical assessments and offering corresponding interventions may help medical staff achieve good patient outcomes in ICU departments.