Congestive heart failure

Similarity Changes Analysis for Heart Rate Fluctuation Regularity as a New Screening Method for Congestive Heart Failure

Congestive heart failure (CHF) is a chronic cardiovascular condition associated with dysfunction of the autonomic nervous system (ANS). Heart rate variability (HRV) has been widely used to assess ANS. This paper proposes a new HRV analysis method, which uses information-based similarity (IBS) transformation and fuzzy approximate entropy (fApEn) algorithm to obtain the fApEn_IBS index, which is used to observe the complexity of autonomic fluctuations in CHF within 24 h. We used 98 ECG records (54 health records and 44 CHF records) from the PhysioNet database. The fApEn_IBS index was statistically significant between the control and CHF groups (p < 0.001). Compared with the classical indices low-to-high frequency power ratio (LF/HF) and IBS, the fApEn_IBS index further utilizes the changes in the rhythm of heart rate (HR) fluctuations between RR intervals to fully extract relevant information between adjacent time intervals and significantly improves the performance of CHF screening. The CHF classification accuracy of fApEn_IBS was 84.69%, higher than LF/HF (77.55%) and IBS (83.67%). Moreover, the combination of IBS, fApEn_IBS, and LF/HF reached the highest CHF screening accuracy (98.98%) with the random forest (RF) classifier, indicating that the IBS and LF/HF had good complementarity. Therefore, fApEn_IBS effusively reflects the complexity of autonomic nerves in CHF and is a valuable CHF assessment tool.

Leveraging Technology to Overcome the "Scalability Problem" in Communication Skills Training Courses

Although multiple consensus statements have called for large-scale efforts to improve clinicians’ communication skills regarding a variety of difficult conversations in medicine, this goal will be difficult to attain because there are no readily scalable, validated communication skills training programs for clinicians. However, novel applications of existing technologies and approaches grounded in learning science can overcome the scalability barriers. Moreover, future advances in virtual reality and artificial intelligence are likely to greatly enhance the possibilities for communication skills training programs. The purpose of this paper is to propose a scalable, theoretically grounded method to train clinicians in advanced communication skills in medicine. First, we summarize four key principles of adult learning relevant to communication skills training in medicine. Second, we discuss recommended practices to design effective technology-enhanced educational interventions, with an emphasis on achieving high amounts of user engagement. Third, we synthesize these principles into a framework for a web- and videoconference-based platform for teaching advanced communication skills in medicine. Once developed, this low-cost, scalable training platform has the potential to allow thousands of clinicians to acquire the advanced communication skills needed for difficult conversations in medicine.

Congestive Heart Failure Predicts Major Complications and Increased Length of Stay in Lower Extremity Pedicled Flap Reconstruction

BACKGROUND

Congestive heart failure affects 6.2 million people in the United States. Patients have a decreased cardiopulmonary reserve and often suffer from peripheral edema, important considerations in lower extremity reconstructive surgery. In this study, the authors sought to determine the impact of congestive heart failure on postoperative outcomes following lower extremity pedicled flap reconstruction using a national multi-institutional database.

METHODS

The authors isolated all patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent lower extremity pedicled flap reconstruction from 2010 to 2016. Preoperative, intraoperative, and postoperative variables were compared between patients with and without congestive heart failure. Multivariable regressions were performed to determine the independent effect of congestive heart failure on postoperative outcomes.

RESULTS

The authors identified 1895 patients who underwent lower extremity pedicled flap reconstruction, of whom 34 suffered from congestive heart failure. No significant difference was observed between patients with versus without congestive heart failure in postoperative wound complications (superficial wound infection, deep wound infection, and wound dehiscence), renal failure, or readmission. On multivariable analysis, congestive heart failure was independently associated with increased cardiopulmonary complications (i.e., myocardial infarction, cardiac arrest, pneumonia, reintubation, and failed ventilator weaning) (OR, 3.92; 95 percent CI, 1.53 to 9.12), septic events (OR, 4.65; 95 percent CI, 2.05 to 10.02), and length of hospital stay (β, 0.37; 95 percent CI, 0.01 to 0.72).

CONCLUSIONS

In patients undergoing lower extremity pedicled flap reconstruction, congestive heart failure independently predicts a four-fold increase in postoperative sepsis and cardiopulmonary complications and a significantly increased length of hospital stay. The authors' findings highlight the need for heightened perioperative vigilance and medical optimization in this high-risk population.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Risk of retinal vein occlusion in patients with diabetes mellitus: A retrospective cohort study

AIMS

To investigate the risk of retinal vein occlusion (RVO) in new-onset diabetes mellitus (DM) patients.

METHODS

This nationwide, retrospective, matched cohort study included 240,761 DM patients registered between January 2003 and December 2005 in the Longitudinal Cohort of Diabetes Patients database. An age- and sex-matched control group comprising 240,761 non-DM patients (case: control = 1:1) was selected from the Taiwan Longitudinal Health Insurance Database 2000. Information for each patient from the index date until December 2013 was collected. The incidence and risk of RVO were compared between the two groups. Cox proportional hazard regression analysis was performed to calculate the adjusted hazard ratio (HR) for RVO after adjustment for potential confounders. The RVO cumulative incidence rate was obtained using Kaplan-Meier analysis.

RESULTS

During the follow-up period, 1,456 DM patients developed RVO (491, central retinal vein occlusion; 965, branch retinal vein occlusion). There was a significantly elevated risk of RVO in DM patients compared with the controls (incidence rate ratio = 1.91, 95% confidence interval [CI] = 1.75-2.08). Patients with DM showed significant risk of RVO after adjustment for potential confounders (hypertension, hyperlipidemia, congestive heart failure, coronary artery disease, and chronic renal disease) in the full cohort (adjusted HR = 1.76, 95% CI = 1.61-1.93). Additionally, patients with hypertension had a significantly higher risk of RVO than patients without hypertension after adjustment for other confounders in the cohort (adjusted HR = 1.50, 95% CI = 1.36-1.65).

CONCLUSIONS

We found that patients with DM have increased risks of RVO. In addition to blood pressure control, we recommend educating patients with DM about RVO, to prevent its subsequent occurrence.

Empirical Mode Decomposition as a Novel Approach to Study Heart Rate Variability in Congestive Heart Failure Assessment

Congestive heart failure (CHF) is a cardiovascular disease related to autonomic nervous system (ANS) dysfunction and fragmented patterns. There is a growing demand for assessing CHF accurately. In this work, 24-h RR interval signals (the time elapsed between two successive R waves of the QRS signal on the electrocardiogram) of 98 subjects (54 healthy and 44 CHF subjects) were analyzed. Empirical mode decomposition (EMD) was chosen to decompose RR interval signals into four intrinsic mode functions (IMFs). Then transfer entropy (TE) was employed to study the information transaction among four IMFs. Compared with the normal group, significant decrease in TE (*→1; information transferring from other IMFs to IMF1, p < 0.001) and TE (3→*; information transferring from IMF3 to other IMFs, p < 0.05) was observed. Moreover, the combination of TE (*→1), TE (3→*) and LF/HF reached the highest CHF screening accuracy (85.7%) in IBM SPSS Statistics discriminant analysis, while LF/HF only achieved 79.6%. This novel method and indices could serve as a new way to assessing CHF and studying the interaction of the physiological phenomena. Simulation examples and transfer entropy applications are provided to demonstrate the effectiveness of the proposed EMD decomposition method in assessing CHF.

Management of acute hypercapnic respiratory failure

PURPOSE OF REVIEW

The objective of this article is to review the most recent literature regarding the management of acute hypercapnic respiratory failure (AHRF).

RECENT FINDINGS

In the field of AHRF management, noninvasive ventilation (NIV) has become the standard method of providing primary mechanical ventilator support. Recently, extracorporeal carbon dioxide removal (ECCO2R) devices have been proposed as new therapeutic option.

SUMMARY

NIV is an effective strategy in specific settings and in selected population with AHRF. To date, evidence on ECCO2R is based only on case reports and case-control trials. Although the preliminary results using ECCO2R to decrease the rate of NIV failure and to wean hypercapnic patients from invasive ventilation are remarkable; further randomized studies are needed to assess the effects of this technique on both short-term and long-term clinical outcomes.

Risk of Retinal Vein Occlusion Following End-Stage Renal Disease

The aim of the study was to investigate the risk of retinal vein occlusion (RVO) following end-stage renal disease (ESRD). The study was designed as a retrospective, nationwide, matched cohort study. The subjects were ESRD patients identified by the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), code 585. The study cohort included 92,774 ESRD patients registered between January 2000 and December 2009 at the Taiwan National Health Insurance Research Database. An age- and sex-matched control group comprised 92,774 patients (case:control = 1:1) selected from the Taiwan Longitudinal Health Insurance Database 2000. Information for each patient was collected from the index date until December 2011. The incidence and risk of RVO were compared between the ESRD and control groups. The adjusted hazard ratio (HR) for RVO after adjustment for potential confounders was obtained by Cox proportional hazard regression analysis. Kaplan-Meier analysis was used to calculate the RVO cumulative incidence rate. The main outcome measure was the incidence of RVO following ESRD. In total, 904 ESRD patients (0.97%) and 410 controls (0.44%) had RVO (P < 0.0001) during the follow-up period, leading to a significantly elevated risk of RVO in the ESRD patients compared with controls (incidence rate ratio = 3.05, 95% confidence interval = 2.72-3.43). After adjustment for potential confounders including diabetes mellitus, hypertension, hyperlipidemia, congestive heart failure, and coronary artery disease, ESRD patients were 3.05 times more likely to develop RVO in the full cohort (adjusted hazard ratio = 3.05, 95% confidence interval = 2.64-3.51). In addition, hypertension patients showed high incidence rate of RVO in the ESRD group compared with controls (incidence rate ratio = 1.71, 95% confidence interval = 1.44-2.03) and maintained significant risk of RVO after adjustment for other confounders in the cohort (adjusted hazard ratio = 1.39, 95% confidence interval = 1.20-1.60). ESRD increases the risk of RVO. For ESRD patients, we recommend education regarding RVO in addition to blood pressure control to prevent subsequent RVO.

Role of Hematocrit Concentration on Successful Extubation in Critically Ill Patients in the Intensive Care Units

Background:

Hematocrit (Hct) is an important parameter for optimal oxygenation during discontinuation from ventilator, but there is no consensus about its concentration and effectiveness on successful extubation.

Objectives:

The current study aimed to determine the role of Hct concentration on extubation failure in critically ill patients.

Patients and Methods:

The current prospective cohort study investigated the effect of age, gender and Hct level on successful extubation of 163 mechanically ventilated patients in Imam Khomeini hospital intensive care units (ICUs), Tehran, Iran. Following successful weaning process, the patients were classified into two groups on the basis of Hct level; 62 with an Hct level of 21% - 27% and the other 101 patients with Hct levels above 27%. The data were analyzed by chi-square test and multiple logistic regressions. A probability value of less than 0.05 was considered significant.

Results:

There was no significant association between the level of Hct concentration and extubation failure (8.9% vs. 9.2%, P = 0.507). Gender and age were significantly associated with extubation failure (OR = 9.1, P = 0.034, OR = 12.5, P = 0.014, respectively). Although the differences between, before and after extubation of PaO₂ and P/F ratio, were of significant values between the two different groups of Hct (P = 0.001, P = 0.004 respectively), they had no effect on the failure of extubation (P= 0.259, P = 0.403, respectively).

Conclusions:

Although some studies showed association between anemia and extubation failure, the current study could not confirm it. The study showed that males, regardless of the Hct level, had a better extubation success rate than those of females.

Cellular cardiomyoplasty: current state of the field

Cellular cardiomyoplasty employs stem cell therapy to regenerate myocardium. Characterized by their potential for proliferation, differentiation and capacity for self-renewal, stem cells are ideally suited for use in regenerative medicine. Supplementing traditional therapeutic modalities aimed at the palliation of congestive heart failure, cellular cardiomyoplasty is an innovative approach aimed at producing functional, viable myocardium following an acute infarction. The primary focus is to prevent the onset of congestive heart failure; however, potential applications aimed at reversing ischemic heart disease are concurrently in development. After decades of research, cellular cardiomyoplasty has moved beyond traditional in vitro and animal models; it is currently being implemented in clinical trials. Despite this monumental advance, certain limitations remain inherent in this process, preventing stem cell therapy from reaching its full potential. On a cellular level, stem cell retention and viability postimplantation continues to be problematic. Solutions under investigation include pioneering advances in cell delivery, in vitro pretreatment, and tissue engineering. Moreover, questions surrounding optimal cell type and cellular mechanisms concerning cellular cardiomyoplasty remain unanswered. Clarification of these issues is essential to ensure continued progression of this new technology. Stem cell therapy has been highly successful within the in vitro and in vivo environment. However, as clinical trials abound, cellular cardiomyoplasty must transition from an experimental concept to an effective therapeutic treatment. This process is hindered by discordance between scientific accrue and practical applicability. This review will provide a comprehensive summary of current innovations on cellular cardiomyoplasty, and future prospects. There will be a particular emphasis on the clinical aspects of stem cell therapy in an attempt to bridge the gap between science and medicine. Overcoming this barrier will render cellular cardiomyoplasty accessible to patients on a global basis.

The lectin-like domain of tumor necrosis factor-alpha improves alveolar fluid balance in injured isolated rabbit lungs

OBJECTIVE

Identification of mechanisms that preserve optimal alveolar fluid balance during pulmonary edema is of great clinical importance. This study was performed to determine whether the lectin-like domain of tumor necrosis factor-alpha (designated TIP) can improve fluid balance in experimental lung injury by affecting alveolocapillary permeability and/or fluid clearance.

DESIGN

Prospective, randomized laboratory investigation.

SETTING

University-affiliated laboratory.

SUBJECTS

Adult male rabbits.

INTERVENTIONS

TIP, a scrambled peptide (scrTIP), dibutyryl cyclic adenosine monophosphate (db-cAMP), or saline was applied to isolated, ventilated, and buffer-perfused rabbit lungs by ultrasonic nebulization, after which hydrostatic edema or endo/exotoxin-induced lung injury was induced and edema formation was assessed. In studies evaluating the resolution of alveolar edema, 2.5 mL of excess fluid was deposited into the alveolar space of isolated lungs by nebulization in the absence or presence of TIP, scrTIP, amiloride, or ouabain or combinations thereof.

MEASUREMENTS AND MAIN RESULTS

Microvascular permeability was largely increased during hydrostatic edema and endo/exotoxin-induced lung injury in saline-treated lungs, or lungs that received scrTIP, as assessed by capillary filtration coefficient (K(f,c)) and fluorescein isothiocyanate-labeled albumin flux across the alveolocapillary barrier. In contrast, TIP- or db-cAMP-treated lungs exhibited significantly lower vascular permeability upon hydrostatic challenge. Similarly, extravascular fluid accumulation, as assessed by fluid retention, wet weight to dry weight ratio, and epithelial lining fluid volume measurements, was largely inhibited by TIP or db-cAMP pretreatment. Furthermore, TIP increased sodium-potassium adenosine triphosphatase (Na,K-ATPase) activity 1.6-fold by promoting Na,K-ATPase exocytosis to the alveolar epithelial cell surface and increased amiloride-sensitive sodium uptake, resulting in a 2.2-fold increase in active Na+ transport, and hence improved clearance of excess fluid from the alveolar space.

CONCLUSIONS

Aerosolized TIP improved alveolar fluid balance by both reducing vascular permeability and enhancing the absorption of excess alveolar fluid in experimental lung injury. These data may suggest a role for TIP as a potential therapeutic agent in pulmonary edema.

Inflammation: a way to understanding the evolution of portal hypertension

BACKGROUND

Portal hypertension is a clinical syndrome that manifests as ascites, portosystemic encephalopathy and variceal hemorrhage, and these alterations often lead to death.

HYPOTHESIS

Splanchnic and/or systemic responses to portal hypertension could have pathophysiological mechanisms similar to those involved in the post-traumatic inflammatory response.The splanchnic and systemic impairments produced throughout the evolution of experimental prehepatic portal hypertension could be considered to have an inflammatory origin. In portal vein ligated rats, portal hypertensive enteropathy, hepatic steatosis and portal hypertensive encephalopathy show phenotypes during their development that can be considered inflammatory, such as: ischemia-reperfusion (vasodilatory response), infiltration by inflammatory cells (mast cells) and bacteria (intestinal translocation of endotoxins and bacteria) and lastly, angiogenesis. Similar inflammatory phenotypes, worsened by chronic liver disease (with anti-oxidant and anti-enzymatic ability reduction) characterize the evolution of portal hypertension and its complications (hepatorenal syndrome, ascites and esophageal variceal hemorrhage) in humans.

CONCLUSION

Low-grade inflammation, related to prehepatic portal hypertension, switches to high-grade inflammation with the development of severe and life-threatening complications when associated with chronic liver disease.

Identifying and overcoming the barriers to high-quality palliative care in the intensive care unit

Initiatives to improve end-of-life care in intensive care units face several important barriers. These include inflated expectations for critical care therapies, which are shared by many clinicians and many patients and families; preoccupation with an unattainable level of prognostic certainty, delaying attention to palliative needs; and fragmentation of the healthcare team into separate "silos" of disciplines and specialties. The article reviews these barriers and relevant empirical evidence. Specific strategies to improve intensive care unit palliative care, including consultation by palliative care specialists, and palliative care quality measurement are discussed.

End-of-life care for the critically ill: A national intensive care unit survey*

OBJECTIVE

One in five Americans dies following treatment in an intensive care unit (ICU), and evidence indicates the need to improve end-of-life care for ICU patients. We conducted this study to elicit the views and experiences of ICU directors regarding barriers to optimal end-of-life care and to identify the type, availability, and perceived benefit of specific strategies that may improve this care.

DESIGN

Self-administered mail survey.

SETTING

Six hundred intensive care units.

PARTICIPANTS

A random, nationally representative sample of nursing and physician directors of 600 adult ICUs in the United States.

INTERVENTIONS

Mail survey.

MEASUREMENTS AND MAIN RESULTS

We asked participants about barriers to end-of-life care (1 = huge to 5 = not at all a barrier), perceived benefit of strategies to improve end-of-life care, and availability of these strategies. From 468 ICUs (78.0% of sample), 590 ICU directors participated (406 nurses [65.1% response] and 184 physicians [31.7% response]). Respondents had a mean of 16.6 yrs (sd 7.6 yrs) of ICU experience. Important barriers to better end-of-life care included patient/family factors, including unrealistic patient/family expectations 2.5 (1.0), inability of patients to participate in discussions 2.7 (0.9), and lack of advance directives 2.9 (1.0); clinician factors, which included insufficient physician training in communication 2.9 (1.1) and competing demands on physicians' time 3.0 (1.1); and institution/ICU factors, such as suboptimal space for family meetings 3.5 (1.2) and lack of a palliative care service 3.4 (1.2). More than 80% of respondents rated 14 of 14 strategies as likely to improve end-of-life care, including trainee role modeling by experienced clinicians, clinician training in communication and symptom management, regular meetings of senior clinicians with families, bereavement programs, and end-of-life care quality monitoring. However, few of these strategies were widely available.

CONCLUSIONS

Intensive care unit directors perceive important barriers to optimal end-of-life care but also universally endorse many practical strategies for quality improvement.

Non-invasive ventilation in acute cardiogenic pulmonary oedema

Non-invasive ventilation (NIV) is the delivery of assisted mechanical ventilation to the lungs, without the use of an invasive endotracheal airway. NIV has revolutionised the management of patients with various forms of respiratory failure. It has decreased the need for invasive mechanical ventilation and its attendant complications. Cardiogenic pulmonary oedema (CPO) is a common medical emergency, and NIV has been shown to improve both physiological and clinical outcomes. From the data presented herein, it is clear that there is sufficiently high level evidence to favour the use of continuous positive airway pressure (CPAP), and that the use of CPAP in patients with CPO decreases intubation rate and improves survival (number needed to treat seven and eight respectively). However, there is insufficient evidence to recommend the use of bilevel positive airway pressure (BiPAP), probably the exception being patients with hypercapnic CPO. More trials are required to conclusively define the role of BiPAP in CPO.

Noninvasive mechanical ventilation in acute cardiogenic pulmonary edema

Acute cardiogenic pulmonary edema is a frequent life-threatening emergency. During the last 10 years, increasing attention has focused on the use of noninvasive ventilation to treat patients with various forms of acute respiratory failure. Numerous physiologic data and clinical studies support the use of noninvasive ventilation during cardiogenic pulmonary edema. Noninvasive ventilation results in rapid improvement of clinical signs of respiratory distress and gas exchange and decreases the need for endotracheal intubation for patients in the ICU with acute hypercapnic respiratory failure related to cardiogenic pulmonary edema. However, no sustained benefit (, decreased late mortality) or benefit for less severe forms of cardiogenic pulmonary edema has been demonstrated yet. Moreover, there are still few data that support the use of a specific mode of ventilation over the others.