Physiologic changes in the hepatopulmonary syndrome before and after liver transplant: A longitudinal and predictor analysis

BACKGROUND AND AIMS

Hepatopulmonary syndrome (HPS) is a common complication of liver disease defined by abnormal oxygenation and intrapulmonary vascular dilatation, treated with liver transplantation. Little is known about changes in HPS physiological parameters over time. We sought to describe baseline clinical and physiological characteristics in HPS and their relationships, temporal changes in physiological parameters before and after transplant, and predictors of changes in oxygenation.

APPROACH AND RESULTS

This was a retrospective cohort study in the Canadian HPS Program (n = 132). Rates of change after diagnosis were: -3.7 (-6.4, -0.96) mm Hg/year for partial pressure of arterial oxygen (PaO 2 ); -26 (-96, 44) m/year for 6-minute walk distance, and 3.3% (-6.6, -0.011) predicted/year for diffusion capacity. Noninvasive shunt of ≥ 20% predicted a slower PaO 2 decline by 0.88 (0.36, 1.4) mm Hg/month. We identified 2 PaO 2 deterioration classes-"very severe disease, slow decliners" (PaO 2 45.0 mm Hg; -1.0 mm Hg/year); and "moderate disease, steady decliners" (PaO 2 65.5 mm Hg; -2.5 mm Hg/year). PaO 2 increased by 6.5 (5.3, 7.7) mm Hg/month in the first year after transplant. The median time to normalization was 149 (116, 184) days. Posttransplant improvement in PaO 2 was 2.5 (0.1, 4.9) mm Hg/month faster for every 10 mm Hg greater pretransplant orthodeoxia.

CONCLUSIONS

We present a large and long longitudinal data analysis in HPS. In addition to rates of physiological decline and improvement before and after liver transplantation, we present novel predictors of PaO 2 decline and improvement rates. Our findings enhance our understanding of the natural history of HPS and provide pathophysiologic clues. Importantly, they may assist providers in prognostication and prioritization before and after transplant.

Quality of virtual care for ambulatory care sensitive conditions: Patient and provider experiences

Background

The COVID-19 pandemic and the need for physical distancing has led to rapid uptake of virtual visits to deliver ambulatory health care. Despite widespread adoption, there has been limited evaluation of the quality of care being delivered through virtual modalities for ambulatory care sensitive conditions (ACSCs).

Objective

To characterize patients’ and providers’ experiences with the quality and sustainability of virtual care for ACSCs.

Design

This was a multi-method study utilizing quantitative and qualitative data from patient surveys, provider surveys, and provider focus groups at a large academic ambulatory care hospital between May 2020 and June 2021. We included patients and providers utilizing telephone or video visits for the following ACSCs: hypertension, angina, heart failure, atrial fibrillation, diabetes, chronic obstructive pulmonary disease, or asthma.

Main measures

Quantitative and qualitative patient and provider survey responses were mapped to the Six Domains of Healthcare Quality framework. Provider focus groups were coded to identify themes within each quality domain.

Key results

Surveys were completed by 110/352 (31%) consenting patients and 20/61 (33%) providers. 5 provider focus groups were held with 14 participants. Patients found virtual visits to be generally more convenient than in-person visits for ACSCs. The perceived effectiveness of virtual visits was dependent on the clinical and social complexity of individual encounters. Respondents reported difficulty forming effective patient-provider relationships in the virtual environment. Patients and providers felt that virtual care has potential to both alleviate and exacerbate structural barriers to equitable access to care.

Conclusions

In a large academic ambulatory care hospital, patients and providers experienced the quality of virtual visits for the management of ACSCs to be variable depending on the biopsychosocial complexity of the individual encounter. Our findings in each quality domain highlight key considerations for patients, providers and institutions to uphold the quality of virtual care for ACSCs.

Patient and provider experience with virtual care in a large, ambulatory care hospital in Ontario, Canada during the COVID-19 pandemic: An observational study (Preprint)

Background

Virtual care use increased during the COVID-19 pandemic. The impact of that shift on patient and provider experiences is unclear.

Objective

We evaluated patient and provider experiences with virtual visits across an academic, ambulatory hospital in Toronto, Canada and assessed predictors of positive experience with virtual care.

Methods

Survey data were analyzed from consenting patients who attended at least one virtual visit (video or telephone) and from consenting providers who delivered at least one virtual visit. Distributions for demographic variables and responses to survey questions are reported, with statistical significance assessed using chi-square tests and t tests. Ordinal logistic regression analysis was used to identify any patient predictors of responses.

Results

During the study period, 253 patients (mean age 45.1, SD 15.6 years) completed 517 video visit surveys, and 147 patients (mean age 41.6, SD 16.4 years) completed 209 telephone visit surveys. A total of 75 and 94 providers completed the survey in June 2020 and June 2021, respectively. On a scale from 1 to 10 regarding likelihood to recommend virtual care to others, fewer providers rated a score of 8 or above compared with patients (providers: 62/94, 66% for video and 49/94, 52% for telephone; patients: 415/517, 80% for video and 150/209, 72% for telephone). Patients of non-White ethnicity had lower odds of rating a high score of 9 or 10 compared with White patients (odds ratio 0.52, 95% CI 0.28-0.99).

Conclusions

Patient experiences with virtual care were generally positive, but provider experiences were less so. Findings suggest potential differences in patient experience by ethnicity, warranting further investigation into equity concerns with virtual care.

Outpatient visit trends for internal medicine ambulatory care sensitive conditions after the COVID-19 pandemic: a time-series analysis

BACKGROUND

The COVID-19 pandemic led to a dramatic shift in the delivery of outpatient medicine with reduced in-person visits and a transition to predominantly virtual visits. We sought to understand trends in visit patterns for ambulatory care sensitive conditions (ACSCs) commonly seen in internal medicine clinics.

METHODS

We included adult outpatients seen for an ACSC between March 15th, 2017 and March 14th, 2021 at a single-centre in Ontario, Canada. Monthly visits were assessed by visit type (new consultation, follow-up), diagnosis, and clinic. Time series analyses compared visit volumes pre- and post-pandemic. Proportion of virtual visits were compared before and during the pandemic. Patient and visit factors were compared between in-person and virtual visits.

RESULTS

8274 patients with 34,021 visits were included. Monthly visits increased by 15% during the pandemic (p <  0.0001). New consultations decreased by 10% (p = 0.0053) but follow-up visits increased by 21% (p <  0.0001). Monthly heart failure visits increased by 43% (p <  0.0001) whereas atrial fibrillation visits decreased. Pre- pandemic, < 1% of visits were virtual compared to 82% during the pandemic (p <  0.0001). Less than half of heart failure visits were virtual whereas > 95% of diabetes visits were virtual.

CONCLUSIONS

We found a significant increase in overall visits to internal medicine clinics driven by increased volumes of follow-up visits, which more than offset decreased new consultations. There was variability in visit trends and uptake of virtual care by visit diagnosis, which may indicate challenges with delivery of virtual care for certain conditions.

Cardiac magnetic resonance derived left atrial strain after ST-elevation myocardial infarction: an independent prognostic indicator

Background

The prognostic value of cardiac magnetic resonance (CMR) derived left atrial (LA) strain, ejection fraction (LAEF) and indexed volumes (LAVI_max and LAVI_min) after ST-elevation myocardial infarction (STEMI) remains controversial. The aim of this study was to assess the relationship between LA function and major adverse cardiovascular events (MACE) after STEMI.

Methods

A total of 202 prospectively recruited patients who underwent CMR at median day 4 after STEMI had complete CMR data for feature tracking assessment. LA reservoir and booster strain were quantified based on the average of three independently repeated measurements.

Results

MACE occurred in 35 patients during a median follow up of 607 days. Patients with MACE had lower median LA reservoir strain (18.9% vs. 29.4%, P<0.001), LA booster strain (9.4% vs. 13.0%, P=0.002) and LAEF (41.5% vs. 49.2%, P<0.001) than patients without MACE. Kaplan-Meier analyses demonstrated a difference in MACE between high- and low-risk groups for LA reservoir strain (cutoff 19.2%, P<0.001), LA booster strain (cutoff 9.7%, P<0.001) and LAEF (cutoff 38.5%, P<0.001). The AUC increased from 0.713 (95% CI: 0.608-0.818) for LVEF to 0.775 (95% CI: 0.680-0.870) when LA reservoir strain was added to LVEF (P=0.047). Univariate Cox regression analysis showed that all LA parameters had a significant effect on MACE, while multivariate analysis found LA reservoir strain was an independent predictor of MACE (HR 0.905; 95% CI: 0.843-0.972, P=0.006).

Conclusions

CMR derived LA reservoir strain independently predicted MACE after STEMI when adjusted for standard risk measures.

Cardiac magnetic resonance derived left atrial function after ST-elevation myocardial infarction: an important prognostic indicator

Background

The prognostic value of cardiac magnetic resonance (CMR) derived left atrial (LA) strain, ejection fraction (LAEF) and volumes (LAVImax and LAVImin) after STEMI is controversial.

Aim

To assess the relationship between LA function and major adverse cardiovascular events (MACE) within 2 years after STEMI.

Methods

We prospectively recruited 213 consecutive STEMI patients who underwent CMR at median day 4. 202 patients had complete CMR data for feature tracking assessment. LA reservoir and booster strain were quantified by one blinded observer based on the average of three independently repeated measurements from two- and four-chamber views. MACE was a composite of all-cause mortality, reinfarction, new or worsening heart failure, stroke and sustained ventricular arrhythmias.

Results

The cohort included 174 (86.1%) males, median age 56 years (IQR 50–65 years). MACE occurred in 35 (17.3%) patients. Patients with MACE had lower median reservoir strain (18.9 vs 29.4%, p&lt;0.001), booster strain (9.4 vs 13.0%, p=0.002) and LAEF (41.5 vs 49.2%, p&lt;0.001), and higher LAVImax (43.5 vs 38.6ml/m2, p=0.019) and LAVImin (23.7 vs 19.3ml/m2, p&lt;0.001) than patients without MACE. Patients with reduced left ventricular ejection fraction (LVEF≤40%) had lower median reservoir strain (22.5 vs 30.1%, p&lt;0.001), booster strain (11.3 vs 12.9%, p=0.021) and LAEF (43.3 vs 50.3%, p&lt;0.001) than patients with LVEF&gt;40%. AUC analyses showed reservoir strain (AUC 0.769; 95% CI 0.676–0.861, p&lt;0.001), booster strain (AUC 0.684; 95% CI 0.558–0.810, p=0.002) and LAEF (AUC 0.698; 95% CI 0.596–0.800, p&lt;0.001) predicted MACE. Kaplan Meier analyses showed a difference in MACE between high- and low-risk groups for reservoir strain (cutoff 21%, p&lt;0.001), booster strain (cutoff 9.6%, p&lt;0.001) and LAEF (cutoff 41%, p&lt;0.001). Univariate Cox regression analyses showed all LA parameters had a significant effect on MACE, while multivariate analyses found additional prognostic utility using reservoir strain.

Conclusion

LA reservoir strain provided incremental prognostic value beyond established clinical and CMR parameters for predicting MACE after STEMI.

Kaplan Meier analyses

Funding Acknowledgement

Type of funding source: None

Outcomes after endoscopic resection of large laterally spreading lesions of the papilla and conventional ampullary adenomas are equivalent

BACKGROUND

Endoscopic resection of ampullary adenomas is a safe and effective alternative to surgical resection. A subgroup of patients have large laterally spreading lesions of the papilla Vateri (LSL-P), which are frequently managed surgically. Data on endoscopic resection of LSL-P are limited and long-term outcomes are unknown. The aim of this study was to compare the outcomes of endoscopic resection of LSL-P with those of standard ampullary adenomas.

METHODS

A retrospective analysis of a prospectively collected and maintained database was conducted. LSL-P was defined as extension of the lesion ≥ 10 mm from the edge of the ampullary mound. Piecemeal endoscopic mucosal resection of the laterally spreading component was followed by resection of the ampulla. Patient, lesion, and procedural data, as well as results of endoscopic follow-up, were collected.

RESULTS

125 lesions were resected. Complete endoscopic resection was achieved in 97.6 % at the index procedure (median lesion size 20 mm, interquartile range [IQR] 13 - 30 mm). Compared with ampullary adenomas, LSL-Ps were significantly larger (median 35 mm vs. 15 mm), contained a higher rate of advanced pathology (38.6 % vs. 18.5 %), and had higher rates of intraprocedural bleeding (50 % vs. 24.7 %) and delayed bleeding (25.0 % vs. 12.3 %). Both groups had similar rates of histologically proven recurrence at first surveillance (16.4 % vs. 17.9 %). Median follow-up for the entire cohort was 18.5 months. For patients with at least two surveillance endoscopies (n = 68; median follow-up 29 months, IQR 18 - 48 months), 95.6 % were clear of disease and considered cured.

CONCLUSIONS

LSL-P can be resected endoscopically with comparable outcomes to standard ampullectomy, albeit with a higher risk of bleeding. Endoscopic treatment should be considered as an alternative to surgical resection, even for large LSL-P.

Endoscopic mucosal resection of large and giant lateral spreading lesions of the duodenum: success, adverse events, and long-term outcomes

BACKGROUND AND AIMS

Large sporadic duodenal adenomas are uncommon but they harbor malignant potential, which requires consideration of definitive treatment. EMR is gaining acceptance as an effective and safe alternative to high-risk surgical procedures, but data on long-term outcomes are limited. Herein we describe the short- and long-term outcomes of these lesions in a tertiary referral center.

METHODS

Prospectively collected data were analyzed to identify risk factors for adverse events and outcomes. Patient demographics, lesion characteristics, and procedural technical data were collected.

RESULTS

From 2007 to 2015, 106 adenomas ≥10 mm were resected (mean patient age, 69 years; 54% male; median size, 25 mm; interquartile range [IQR], 19-40). Complete endoscopic resection was achieved in 96%. Intraprocedural bleeding occurred in 43% of cases and was associated with lesion size (P < .001), number of resected specimens (P = .003), and longer procedures (P = .001). Delayed bleeding occurred in 15% (56% did not require active intervention) and was associated with lesion size (P = .03). Perforation occurred in 3 patients. The 30-day mortality was 0%. Median follow-up was 22 months (IQR, 7-45). Histologically proven adenoma recurrence was identified and treated in 12 of 83 patients (14.4%) on first surveillance endoscopy. For the 53 patients for whom follow-up ≥12 months was available (median follow-up, 36 months; IQR, 24-51), 48 patients (90.6%) were free of adenoma and considered cured.

CONCLUSIONS

In a tertiary referral center, endoscopic resection of duodenal adenomas is a safe and effective alternative to surgery. Lesion size is strongly associated with adverse events, particularly intraprocedural bleeding and delayed bleeding. Good long-term outcomes are demonstrated.

Internationational Labor Movements, Trade Flows and Migration Transitions: A Theoretical Perspective

This article presents a theoretical analysis of how the processes of industrialization and development interact with international trade in goods or services to influence a country's turning point from labor exporter to labor importer. It is concluded that trade in goods complements capital movements but substitutes for labor movements, whereas trade in services and labor movements complement each other. The proposed analytical framework suggests that both international trade and migration may contribute to, but cannot lead to, a development process that brings about a migration transition in surplus labor economies.

Chronically homeless persons' participation in an advance directive intervention: A cohort study

BACKGROUND

Chronically homeless individuals have high rates of hospitalization and death, and they may benefit from the completion of advance directives.

AIM

To determine the rate of advance directive completion using a counselor-guided intervention, identify characteristics associated with advance directive completion, and describe end-of-life care preferences in a group of chronically homeless individuals.

DESIGN

Participants completed a survey and were offered an opportunity to complete an advance directive with a trained counselor.

PARTICIPANTS

A total of 205 residents of a shelter in Canada for homeless men (89.1% of those approached) participated from April to June 2013.

RESULTS

Duration of homelessness was ⩾12 months in 72.8% of participants, and 103 participants (50.2%) chose to complete an advance directive. Socio-demographic characteristics, health status, and health care use were not associated with completion of an advance directive. Participants were more likely to complete an advance directive if they reported thinking about death on a daily basis, believed that thinking about their friends and family was important, or reported knowing their wishes for end-of-life care but not having told anyone about these wishes. Among individuals who completed an advance directive, 61.2% named a substitute decision maker, and 94.1% expressed a preference to receive cardiopulmonary resuscitation in the event of a cardiorespiratory arrest if there was a chance of returning to their current state of health.

CONCLUSION

A counselor-guided intervention can achieve a high rate of advance directive completion among chronically homeless persons. Most participants expressed a preference to receive cardiopulmonary resuscitation in the event of a cardiorespiratory arrest.

Proposed management algorithm for severe hypoxemia after liver transplantation in the hepatopulmonary syndrome

The hepatopulmonary syndrome (HPS) is defined as the triad of liver disease, intrapulmonary vascular dilatation, and abnormal gas exchange, and is found in 10-32% of patients with liver disease. Liver transplantation is the only known cure for HPS, but patients can develop severe posttransplant hypoxemia, defined as a need for 100% inspired oxygen to maintain a saturation of ≥85%. This complication is seen in 6-21% of patients and carries a 45% mortality. Its management requires the application of specific strategies targeting the underlying physiologic abnormalities in HPS, but awareness of these strategies and knowledge on their optimal use is limited. We reviewed existing literature to identify strategies that can be used for this complication, and developed a clinical management algorithm based on best evidence and expert opinion. Evidence was limited to case reports and case series, and we determined which treatments to include in the algorithm and their recommended sequence based on their relative likelihood of success, invasiveness, and risk. Recommended therapies include: Trendelenburg positioning, inhaled epoprostenol or nitric oxide, methylene blue, embolization of abnormal pulmonary vessels, and extracorporeal life support. Availability and use of this pragmatic algorithm may improve management of this complication, and will benefit from prospective validation.

Imatinib for the treatment of pulmonary arterial hypertension and pulmonary capillary hemangiomatosis

Despite currently available treatments, the prognoses of pulmonary arterial hypertension (PAH) and pulmonary capillary hemangiomatosis (PCH) remain poor. Platelet-derived growth factor and its receptor (PDGFR) have been implicated in the pathogenesis of pulmonary hypertension in PAH and PCH. Imatinib, a PDGFR antagonist, may be beneficial in the treatment of both conditions because of its potent antiproliferative effect. We report two cases that demonstrate the potential for safe and efficacious use of imatinib in PAH and PCH.

Defining and characterizing severe hypoxemia after liver transplantation in hepatopulmonary syndrome

Hepatopulmonary syndrome is defined as a triad of liver disease, intrapulmonary vascular dilatations, and abnormal gas exchange, and it carries a poor prognosis. Liver transplantation is the only known cure for this syndrome. Severe hypoxemia in the early postoperative period has been reported to be a major complication and often leads to death in this population, but it has been poorly characterized. We sought to propose an objective definition for this complication and to describe its risk factors, incidence, and outcomes. We performed a systematic literature search and reviewed our single-center experience to characterize this complication. On the basis of the most commonly applied definition in 27 identified studies, we objectively defined severe postoperative hypoxemia as hypoxemia requiring a 100% fraction of inhaled oxygen to maintain a saturation ≥ 85% and out of proportion to any concurrent lung process. Nineteen of the 27 reports (70%) fulfilled this definition, as did 4 of the 21 patients (19%) at our center. We determined the prevalence and mortality of this complication from reports including 10 or more consecutive patients and providing sufficient postoperative details to determine whether this complication had occurred. In these reports, the prevalence of this complication was 12% (25/209). For the 11 cases with reported outcomes, the posttransplant mortality rate was 45% (5/11). There was a trend toward an increased risk of developing this complication in patients with very severe preoperative hypoxemia, defined as a partial pressure of arterial oxygen ≤ 50 mm Hg (8/41 with very severe hypoxemia versus 3/49 without severe hypoxemia, P = 0.053), and there was a significantly increased risk for patients with anatomic shunting ≥ 20% (7/25 with anatomic shunting ≥ 20% versus 1/25 without anatomic shunting ≥ 20%, P = 0.049). In conclusion, increased preoperative vigilance for this common complication is required among high-risk patients, and further research is required to identify the best management strategies.

Potential role of the gene transcription factor cyclic AMP-responsive element binding protein in ethanol withdrawal-related anxiety

This investigation examined the effects of acute and chronic ethanol exposure and its withdrawal on the cAMP-responsive element binding protein (CREB) and the activator protein-1 (AP-1) gene transcription factors in the rat brain. The anxiogenic effects of ethanol withdrawal after acute or protracted ethanol treatment of rats were measured by the elevated plus-maze (EPM) test. It was observed that ethanol withdrawal after acute ethanol treatment has no effect on open-arm activity (percent of open-arm entries and the mean percent of time spent on the open arms) of rats on the EPM test. On the other hand, the time course studies of the development of anxiety during ethanol withdrawal (0, 12, 24, and 72 h) after 15 days of ethanol treatment indicate that peak anxiety (significant decrease in open-arm activity) occurred at 24 h of ethanol withdrawal in rats. It was observed that acute ethanol treatment and its withdrawal (24 h) had no effect on CRE- or AP-1 DNA-binding activities in the rat cortex as determined by the electrophoretic gel-mobility shift assay. It was also found that chronic ethanol treatment and its withdrawal (24 h) had no effect on AP-1 DNA-binding activity in the rat cortex. Investigation of the time course studies of changes in CRE-DNA-binding activity during ethanol withdrawal (0, 12, 24, and 72 h) after 15 days of ethanol treatment indicated that the peak reduction of CRE-DNA-binding activity occurred at 24 h of ethanol withdrawal. The changes in the immunolabeling of the CREB-related target, that is, brain-derived neurotrophic factor (BDNF), in the rat cortex during chronic ethanol treatment and its withdrawal (24 h) were examined using western blotting. It was found that 24 h but not 0 h of ethanol withdrawal after 15 days of ethanol treatment caused a significant decrease in the immunolabeling of BDNF in the rat cortex. Fluoxetine (alone) treatment of rats for 1 or 15 days had no effect on open-arm activity and cortical CRE-DNA-binding activity. However, when fluoxetine was administered concurrently with ethanol treatment for 15 days, it caused a reversal of the anxiogenic effects of ethanol withdrawal and antagonized the down-regulation of CRE-DNA-binding activity and of the decrease in immunolabeling of BDNF in the cortices of ethanol-withdrawn rats. On the other hand, acute fluoxetine treatment produced normalization of the reduction of cortical CRE-DNA binding in ethanol-withdrawn rats (24 h) but did not reach the level of significance compared with normal control rats. Acute fluoxetine treatment had no effect on anxiety in ethanol-withdrawn rats. Taken together, these results suggest the possibility that decreased CRE-DNA-binding activity in the rat cortex may be associated with the molecular mechanisms of ethanol dependence (i.e., ethanol withdrawal-related anxiety).