Building Learning Healthcare Systems for Critical Care Medicine

Learning healthcare systems are an evolving way of integrating informatics, analytics, and continuous improvement into daily practice in healthcare. This article discusses strategies to build learning healthcare systems for critical care medicine.

Diagnosis and management of autoimmune diseases in the ICU

Autoimmune diseases encompass a broad spectrum of disorders characterized by disturbed immunoregulation leading to the development of specific autoantibodies, resulting in inflammation and multiple organ involvement. A distinction should be made between connective tissue diseases (mainly systemic lupus erythematosus, systemic scleroderma, inflammatory muscle diseases, and rheumatoid arthritis) and vasculitides (mainly small-vessel vasculitis such as antineutrophil cytoplasmic antibody-associated vasculitis and immune-complex mediated vasculitis). Admission of patients with autoimmune diseases to the intensive care unit (ICU) is often triggered by disease flare-ups, infections, and organ failure and is associated with high mortality rates. Management of these patients is complex, including prompt disease identification, immunosuppressive treatment initiation, and life-sustaining therapies, and requires multi-disciplinary involvement. Data about autoimmune diseases in the ICU are limited and there is a need for multicenter, international collaboration to improve patients' diagnosis, management, and outcomes. The objective of this narrative review is to summarize the epidemiology, clinical features, and selected management of severe systemic autoimmune diseases.

The impact of race on utilization of durable left ventricular assist device therapy in patients with advanced heart failure

BACKGROUND

Heart failure affects >6 million people in the United States alone and is most prevalent in Black patients who suffer the highest mortality risk. Yet prior studies have suggested that Black patients are less likely to receive advanced heart failure therapy. We hypothesized that Black patients would have decreased rates of durable left ventricular assist device (LVAD) implantation within our expansive heart failure program.

METHODS

A retrospective single-center cohort study was conducted at a single high-volume academic medical center. Patients between 18 and 85 years admitted with a diagnosis of cardiogenic shock or congestive heart failure between 1, 2013 and 12, 2017 with a left ventricular ejection fraction < 30% and inotropic dependence or need for mechanical circulatory support were included. Patients with contraindications to durable LVAD were excluded. An adjusted logistic regression model for durable LVAD implantation within 90 days of the index admission was used to determine the effect of race on durable LVAD implantation.

RESULTS

Among the 702 study patients (60.9% White, 34.1% Black), durable LVAD implantation was performed within 90 days of the index admission in 183 (26%) of the cohort. After multivariate analysis, Black patients were not found to have a statistically significant difference in durable LVAD implantation rates compared to White patients in our study (OR: 0.68 [95% confidence interval: 0.45-1.04; p: .074]).

CONCLUSIONS

Black patients in our study did not have a statistically significant difference in the rate of durable LVAD implantation compared with White patients after adjustments were made for age, sex, socioeconomic, and clinical covariates. Larger prospective studies are needed to validate these findings.

Racial and Ethnic Differences in the Prevalence of Do-Not-Resuscitate Orders among Older Adults with Severe Traumatic Brain Injury

Background

Older adults suffering from traumatic brain injury (TBI) are subject to higher injury burden and mortality. Do Not Resuscitate (DNR) orders are used to provide care aligned with patient wishes, but they may not be equitably distributed across racial/ethnic groups. We examined racial/ethnic differences in the prevalence of DNR orders at hospital admission in older patients with severe TBI.

Methods

We conducted a retrospective cohort study using the National Trauma Databank (NTDB) between 2007 to 2016. We examined patients ≥ 65 years with severe TBI. For our primary aim, the exposure was race/ethnicity and outcome was the presence of a documented DNR at hospital admission. We conducted an exploratory analysis of hospital outcomes including hospital mortality, discharge to hospice, and healthcare utilization (intracranial pressure monitor placement, hospital LOS, and duration of mechanical ventilation).

Results

Compared to White patients, Black patients (OR 0.48, 95% CI 0.35-0.64), Hispanic patients (OR 0.54, 95% CI 0.40-0.70), and Asian patients (OR 0.63, 95% CI 0.44-0.90) had decreased odds of having a DNR order at hospital admission. Patients with DNRs had increased odds of hospital mortality (OR 2.16, 95% CI 1.94-2.42), discharge to hospice (OR 2.08, 95% CI 1.75-2.46), shorter hospital LOS (−2.07 days, 95% CI −3.07 to −1.08) and duration of mechanical ventilation (−1.09 days, 95% CI −1.52 to −0.67). There was no significant difference in the utilization of ICP monitoring (OR 0.94, 95% CI 0.78-1.12).

Conclusions

We found significant racial and ethnic differences in the utilization of DNR orders among older patients with severe TBI. Additionally. DNR orders at hospital admission were associated with increased in-hospital mortality, increased hospice utilization, and decreased healthcare utilization. Future studies should examine mechanisms underlying race-based differences in DNR utilization.

Association of Early Multiple Organ Dysfunction With Clinical and Functional Outcomes Over the Year Following Traumatic Brain Injury: A Transforming Research and Clinical Knowledge in Traumatic Brain Injury Study

OBJECTIVES

Traumatic brain injury is a leading cause of death and disability in the United States. While the impact of early multiple organ dysfunction syndrome has been studied in many critical care paradigms, the clinical impact of early multiple organ dysfunction syndrome in traumatic brain injury is poorly understood. We examined the incidence and impact of early multiple organ dysfunction syndrome on clinical, functional, and disability outcomes over the year following traumatic brain injury.

DESIGN

Retrospective cohort study.

SETTING

Patients enrolled in the Transforming Clinical Research and Knowledge in Traumatic Brain Injury study, an 18-center prospective cohort study of traumatic brain injury patients evaluated in participating level 1 trauma centers.

SUBJECTS

Adult (age > 17 yr) patients with moderate-severe traumatic brain injury (Glasgow Coma Scale < 13). We excluded patients with major extracranial injury (Abbreviated Injury Scale score ≥ 3).

INTERVENTIONS

Development of early multiple organ dysfunction syndrome, defined as a maximum modified Sequential Organ Failure Assessment score greater than 7 during the initial 72 hours following admission.

MEASUREMENTS AND MAIN RESULTS

The main outcomes were: hospital mortality, length of stay, 6-month functional and disability domains (Glasgow Outcome Scale-Extended and Disability Rating Scale), and 1-year mortality. Secondary outcomes included: ICU length of stay, 3-month Glasgow Outcome Scale-Extended, 3-month Disability Rating Scale, 1-year Glasgow Outcome Scale-Extended, and 1-year Disability Rating Scale. We examined 373 subjects with moderate-severe traumatic brain injury. The mean (sd) Glasgow Coma Scale in the emergency department was 5.8 (3.2), with 280 subjects (75%) classified as severe traumatic brain injury (Glasgow Coma Scale 3-8). Among subjects with moderate-severe traumatic brain injury, 252 (68%) developed early multiple organ dysfunction syndrome. Subjects that developed early multiple organ dysfunction syndrome had a 75% decreased odds of a favorable outcome (Glasgow Outcome Scale-Extended 5-8) at 6 months (adjusted odds ratio, 0.25; 95% CI, 0.12-0.51) and increased disability (higher Disability Rating Scale score) at 6 months (adjusted mean difference, 2.04; 95% CI, 0.92-3.17). Subjects that developed early multiple organ dysfunction syndrome experienced an increased hospital length of stay (adjusted mean difference, 11.4 d; 95% CI, 7.1-15.8), with a nonsignificantly decreased survival to hospital discharge (odds ratio, 0.47; 95% CI, 0.18-1.2).

CONCLUSIONS

Early multiple organ dysfunction following moderate-severe traumatic brain injury is common and independently impacts multiple domains (mortality, function, and disability) over the year following injury. Further research is necessary to understand underlying mechanisms, improve early recognition, and optimize management strategies.

Clinical Data Extraction During Public Health Emergencies: A Blockchain Technology Assessment

OBJECTIVE

We sought to explore the technical and legal readiness of healthcare institutions for novel data-sharing methods that allow clinical information to be extracted from electronic health records (EHRs) and submitted securely to the Food and Drug Administration's (FDA's) blockchain through a secure data broker (SDB).

MATERIALS AND METHODS

This assessment was divided into four sections: an institutional EHR readiness assessment, legal consultation, institutional review board application submission, and a test of healthcare data transmission over a blockchain infrastructure.

RESULTS

All participating institutions reported the ability to electronically extract data from EHRs for research. Formal legal agreements were deemed unnecessary to the project but would be needed in future tests of real patient data exchange. Data transmission to the FDA blockchain met the success criteria of data connection from within the four institutions' firewalls, externally to the FDA blockchain via a SDB.

DISCUSSION

The readiness survey indicated advanced analytic capability in hospital institutions and highlighted inconsistency in Fast Healthcare Interoperability Resources format utilitzation across institutions, despite requirements of the 21st Century Cures Act. Further testing across more institutions and annual exercises leveraging the application of data exchange over a blockchain infrastructure are recommended actions for determining the feasibility of this approach during a public health emergency and broaden the understanding of technical requirements for multisite data extraction.

CONCLUSION

The FDA's RAPID (Real-Time Application for Portable Interactive Devices) program, in collaboration with Discovery, the Critical Care Research Network's PREP (Program for Resilience and Emergency Preparedness), identified the technical and legal challenges and requirements for rapid data exchange to a government entity using the FDA blockchain infrastructure.

Clinical Data Extraction During Public Health Emergencies: A Blockchain Technology Assessment

OBJECTIVE

We sought to explore the technical and legal readiness of healthcare institutions for novel data-sharing methods that allow clinical information to be extracted from electronic health records (EHRs) and submitted securely to the Food and Drug Administration's (FDA's) blockchain through a secure data broker (SDB).

MATERIALS AND METHODS

This assessment was divided into four sections: an institutional EHR readiness assessment, legal consultation, institutional review board application submission, and a test of healthcare data transmission over a blockchain infrastructure.

RESULTS

All participating institutions reported the ability to electronically extract data from EHRs for research. Formal legal agreements were deemed unnecessary to the project but would be needed in future tests of real patient data exchange. Data transmission to the FDA blockchain met the success criteria of data connection from within the four institutions' firewalls, externally to the FDA blockchain via a SDB.

DISCUSSION

The readiness survey indicated advanced analytic capability in hospital institutions and highlighted inconsistency in Fast Healthcare Interoperability Resources format utilitzation across institutions, despite requirements of the 21st Century Cures Act. Further testing across more institutions and annual exercises leveraging the application of data exchange over a blockchain infrastructure are recommended actions for determining the feasibility of this approach during a public health emergency and broaden the understanding of technical requirements for multisite data extraction.

CONCLUSION

The FDA's RAPID (Real-Time Application for Portable Interactive Devices) program, in collaboration with Discovery, the Critical Care Research Network's PREP (Program for Resilience and Emergency Preparedness), identified the technical and legal challenges and requirements for rapid data exchange to a government entity using the FDA blockchain infrastructure.

Acute Care Resource Use After Elective Surgery in the United States: Implications During the COVID-19 Pandemic

BACKGROUND

The COVID-19 pandemic created pressure to delay inpatient elective surgery to increase US health care capacity. This study examined the extent to which common inpatient elective operations consume acute care resources.

METHODS

This cross-sectional study used the Premier Healthcare Database to examine the distribution of inpatient elective operations in the United States from the fourth quarter of 2015 through the second quarter of 2018. Primary outcomes were measures of acute care use after 4 common elective operations: joint replacement, spinal fusion, bariatric surgery, and coronary artery bypass grafting. A framework for matching changing demand with changes in supply was created by overlaying acute care data with publicly available outbreak capacity data.

RESULTS

Elective coronary artery bypass grafting (n = 117 423) had the highest acute care use: 92.8% of patients used intensive care unit beds, 89.1% required postoperative mechanical ventilation, 41.0% required red blood cell transfusions, and 13.3% were readmitted within 90 days of surgery. Acute care use was also substantial after spinal fusion (n = 203 789): 8.3% of patients used intensive care unit beds, 2.2% required postoperative mechanical ventilation, 9.2% required red blood cell transfusions, and 9.3% were readmitted within 90 days of surgery. An example of a framework for matching hospital demand with elective surgery supply is provided.

CONCLUSIONS

Acute care needs after elective surgery in the United States are consistent and predictable. When these data are overlaid with national hospital capacity models, rational decisions regarding matching supply to demand can be achieved to meet changing needs.

Abstract P527: Temporal Trend of Mechanical Thrombectomy Utilization in Treatment of Perioperative Ischemic Stroke Following Elective Inpatient Surgery in the United States

Background: Perioperative ischemic stroke (PIS) significantly increases morbidity and mortality in patients undergoing elective surgery. Mechanical thrombectomy (MT) can improve outcomes of ischemic stroke, but the frequency and trend of its utilization for treatment of PIS is not studied.

Methods: In this retrospective observational study using the Premier Healthcare Database, we identified adults who underwent elective inpatient surgery from 2008 to 2018. Patients with PIS were identified using the established International Classification of Diseases (ICD) ninth revision codes or equivalent ICD, tenth revision codes. Cases that underwent MT were further identified using established ICD9 and ICD10 procedure codes. Descriptive statistics were used to compare patient and center level characteristics between patients who received MT versus did not after PIS.

Results: Of 6,349,668 patients with elective inpatient surgery, 12,507 (0.2%) had PIS. The mean age (and standard deviation) of these patients was 69.5 (11.7) years, and 48.8% were female. MT was used in 1.7% of all patients with PIS and its use increased from 0.0% in 3 rd quarter, 2008 to 4.4% in 4 th quarter, 2018. There was a significant increase in the use of MT after 3 rd quarter, 2015 when MT use was incorporated in acute stroke treatment guidelines (1.14% before 3 rd quarter, 2015 versus 3.07% after; p<0.0001). Amongst patients with PIS, patients who received mechanical thrombectomy were more likely to have their surgery performed at a teaching institute (67.3% versus 53.9%).

Conclusion: Although there was a significant increase in rates of utilization of MT, rates of utilization remain low, especially in non-teaching hospitals. This highlights improvements in the management of perioperative ischemic strokes and further opportunities to improve outcomes.

Association of Severe Acute Kidney Injury with Mortality and Healthcare Utilization Following Isolated Traumatic Brain Injury

BACKGROUND/OBJECTIVE

Traumatic brain injury (TBI) is a leading cause of morbidity, mortality, and disability in the USA. While cardiopulmonary dysfunction can result in poor outcomes following severe TBI, the impact of acute kidney injury (AKI) is poorly understood. We examined the association of severe AKI with hospital mortality and healthcare utilization following isolate severe TBI.

METHODS

We conducted a retrospective cohort study using the National Trauma Data Bank from 2007 to 2014. We identified a cohort of adult patients with isolated severe TBI and described the incidence of severe AKI, corresponding to Acute Kidney Injury Network stage 3 disease or greater. We examined the association of severe AKI with the primary outcome of hospital mortality using multivariable logistic regression models. In secondary analyses, we examined the association of severe AKI with dialysis catheter placement, tracheostomy and gastrostomy utilization, and hospital length of stay.

RESULTS

There were 37,851 patients who experienced isolated severe TBI during the study period. Among these patients, 787 (2.1%) experienced severe (Stage 3 or greater) AKI. In multivariable models, the development of severe AKI in the hospital was associated with in-hospital mortality (OR 2.03, 95% CI 1.64-2.52), need for tracheostomy (OR 2.10, 95% CI 1.52-2.89), PEG tube placement (OR 1.88, 95% CI 1.45-2.45), and increased hospital length of stay (p < 0.001).

CONCLUSIONS

The overall incidence of severe AKI is relatively low (2.1%), but is associated with increased mortality and multiple markers of increased healthcare utilization following severe TBI.

Racial and Ethnic Differences in Health Care Utilization Following Severe Acute Brain Injury in the United States

OBJECTIVE

To examine racial and ethnic differences in the utilization of 3 interventions (tracheostomy placement, gastrostomy tube placement, and hospice utilization) among patients with severe acute brain injury (SABI).

DESIGN

Retrospective cohort study.

SETTING

Data from the National Inpatient Sample, from 2002 to 2012.

PATIENTS

Adult patients with SABI defined as a primary diagnosis of stroke, traumatic brain injury, or post-cardiac arrest who received greater than 96 hours of mechanical ventilation.

EXPOSURE

Race/ethnicity, stratified into 5 categories (white, black, Hispanic, Asian, and other).

MEASUREMENTS AND MAIN RESULTS

Data from 86 246 patients were included in the cohort, with a mean (standard deviation) age of 60 (18) years. In multivariable analysis, compared to white patients, black patients had an 20% increased risk of tracheostomy utilization (relative risk [RR]: 1.20, 95% CI: 1.16-1.24, P < .001), Hispanic patients had a 10% increased risk (RR: 1.10, 95% CI: 1.06-1.14, P < .001), Asian patients had an 8% increased risk (RR: 1.08, 95% CI: 1.01-1.16, P = .02), and other race patients had an 10% increased risk (RR: 1.10, 95% CI: 1.04-1.16, P < .001). A similar relationship was observed for gastrostomy utilization. In multivariable analysis, compared to white patients, black patients had a 25% decreased risk of hospice discharge (RR: 0.75, 95% CI: 0.67-0.85, P < .001), Hispanic patients had a 20% decreased risk (RR: 0.80, 95% CI: 0.69-0.94, P < .01), and Asian patients had a 47% decreased risk (RR: 0.53, 95% CI: 0.39-0.73, P < .001). There was no observed relationship between race/ethnicity and in-hospital mortality.

CONCLUSIONS

Minority race was associated with increased utilization of tracheostomy and gastrostomy, as well as decreased hospice utilization among patients with SABI. Further research is needed to better understand the mechanisms underlying these race-based differences in critical care.

Mitochondrial quality control in alveolar epithelial cells damaged by S. aureus pneumonia in mice

Mitochondrial damage is often overlooked in acute lung injury (ALI), yet most of the lung's physiological processes, such as airway tone, mucociliary clearance, ventilation-perfusion (Va/Q) matching, and immune surveillance require aerobic energy provision. Because the cell's mitochondrial quality control (QC) process regulates the elimination and replacement of damaged mitochondria to maintain cell survival, we serially evaluated mitochondrial biogenesis and mitophagy in the alveolar regions of mice in a validated Staphylococcus aureus pneumonia model. We report that apart from cell lysis by direct contact with microbes, modest epithelial cell death was detected despite significant mitochondrial damage. Cell death by TdT-mediated dUTP nick-end labeling staining occurred on days 1 and 2 postinoculation: apoptosis shown by caspase-3 cleavage was present on days 1 and 2, while necroptosis shown by increased levels of phospho- mixed lineage kinase domain-like protein (MLKL) and receptor-interacting serine/threonine-protein kinase 1 (RIPK1) was present on day 1 Cell death in alveolar type I (AT₁) cells assessed by bronchoalveolar lavage fluid receptor for advanced glycation end points (RAGE) levels was high, yet AT₂ cell death was limited while both mitochondrial biogenesis and mitophagy were induced. These mitochondrial QC mechanisms were evaluated mainly in AT₂ cells by localizing increases in citrate synthase content, increases in nuclear mitochondrial biogenesis regulators nuclear respiratory factor-1 (NRF-1) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), and increases in light chain 3B protein (LC3-I)/LC3II ratios. Concomitant changes in p62, Pink 1, and Parkin protein levels indicated activation of mitophagy. By confocal microscopy, mitochondrial biogenesis and mitophagy were often observed on day 1 within the same AT₂ cells. These findings imply that mitochondrial QC activation in pneumonia-damaged AT₂ cells promotes cell survival in support of alveolar function.

Alpha-adrenergic mRNA subtype expression in the human nasal turbinate

PURPOSE

Alpha-adrenergic receptor (AR) agonist drugs (e.g., epinephrine) are commonly used for upper airway procedures, to shrink the mucosa, retard absorption of local anesthetic agents, and improve visualization by limiting hemorrhage. Decongestant therapy often also includes alphaAR agonist agents, however overuse of these drugs (e.g., oxymetazoline) can result in chronic rhinitis and rebound increases in nasal secretion. Since current decongestants stimulate alphaARs non-selectively, characterization of alphaAR subtype distribution in human airway (nasal turbinate) offers an opportunity to refine therapeutic targets while minimizing side-effects. We, therefore, investigated alphaAR subtype expression in human nasal turbinate within epithelial, duct, gland, and vessel cells using in situ hybridization.

METHODS

Since sensitive and specific anti-receptor antibodies and highly selective alphaAR subtype ligands are currently unavailable, in situ hybridization was performed on sections of three human nasal turbinate samples to identify distribution of alphaAR subtype mRNA. Subtype specific (35)S-labelled mRNA probes were incubated with nasal turbinate sections, and protected fragments remaining after RNase treatment analyzed by light and darkfield microscopy.

RESULTS

In non-vascular tissue alpha(1d) AR mRNA predominates, whereas notably the alpha(2c) is the only alphaAR subtype present in the sinusoids and arteriovenous anastamoses.

CONCLUSION

Combined with the current understanding that AR-mediated constriction of nasal sinusoids underpins decongestant therapies that minimize secretions and shrink tissues for airway procedures, these findings suggest that alpha(2c) AR subtypes provide a novel selective target for decongestant therapy in humans.

Beyond the biopsychosocial model: new approaches to doctor-patient interactions

BACKGROUND

The biopsychosocial model has been a cornerstone for the training of family physicians; however, little is known about the use of this model in community practice. This study, conducted in an urban Native American health center, examined the application of the biopsychosocial model by an experienced family physician (Dr M).

METHODS

Interactions between Dr M and 9 Native Americans with type 2 diabetes were audio-recorded following preliminary interviews. Interpretations of the interactions were elicited from Dr M through interpersonal process recall and interpretive dialogue sessions. The author analyzed this data using techniques from interpretive anthropology and narrative discourse analysis.

RESULTS

In a preliminary interview, Dr M described a sophisticated biopsychosocial approach to practice. However, she viewed her actual interactions with these patients as imbued with misunderstanding, mistrust, and disconnection. This occurred in spite of her experience and commitment to providing culturally sensitive primary care.

CONCLUSIONS

Biopsychosocial models of disease may conflict with patient-centered approaches to communication. To overcome difficulties in her practice environment, Dr M adopted a strategy that combined an instrumental biopsychosocial approach with a utilitarian mode of knowing and interacting with patients. The misunderstandings, mistrust, and constrained interactions point to deeper problems with the way knowledge is formed in clinical practice. We need further understanding of the interrelationships between physicians' clinical environments, knowledge of patients, and theories of disease. These elements are interwoven in the physicians' patient-specific narratives that influence their interactions in primary care settings.

Differential receptor usage by measles virus strains

Recently, we demonstrated that infection of cells with all measles virus (MV) strains tested was inhibited by antibodies against CD46, although not all strains caused downregulation of the MV receptor CD46 from the surface of human cells. We now show that infection of cells with MV strain WTFb, a variant of wild-type isolate WTF which has been isolated and propagated on human BJAB cells, is not inhibited by antibodies against CD46. In contrast, infection of cells with the closely related strain WTFv, a Vero cell-adapted variant of WTF, is inhibited by antibodies against CD46. This observation led us to investigate the interaction of these viruses and the vaccine strain Edmonston (Edm) with CD46 and target cells. Cellular receptors with high affinity binding for WTFb are present on BJAB cells, but not on transfected CD46-expressing CHO cells. In contrast to the Edm strain, virus particles and solubilized envelope glycoproteins of WTFb have a very limited binding capacity to CD46. Furthermore, we show that recombinant soluble CD46 either does not bind, or binds very weakly, to WTFb glycoproteins expressed on the cell surface. Our findings indicate that wild-type MV strain WTFb and vaccine strain Edm use different binding sites on human cells. In addition, the results suggest that MV strains may alternatively use CD46 and an unknown molecule as receptors, and that the degree of usage of both receptors may be MV strain-specific.

Mapping amino acids of the measles virus hemagglutinin responsible for receptor (CD46) downregulation

We compared the amino acid sequences of groups of receptor (CD46) downregulating and nondownregulating measles virus (MV) hemagglutinins (Hs) and identified seven group-specific differences as candidates for the mediation of the observed differential effects. Using site-directed mutagenesis, we mutated the chosen amino acids of the H of MV-strain WTF (WTF-H), a nondownregulating H, and Introduced the corresponding amino acids of Edmonston-H (Edm-H), a downregulating H. We identified four amino acids, 211G, 243R, 451V, and 481Y, which influenced the downregulative function when introduced into WTF-H. The double mutation 451V and 481Y in WTF-H led to a degree of CD46 downregulation comparable to that of Edm-H. Conversely, introducing amino acids 451E and 481N into Edm-H resulted in a loss of the downregulative function. These results indicate that these amino acids play a decisive role in the H-CD46 interaction.