Prevalence and Survival of Prolonged Venovenous Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome: An Analysis of the Extracorporeal Life Support Organization Registry

OBJECTIVES

To examine trends in utilization and outcomes among patients with the acute respiratory distress syndrome (ARDS) requiring prolonged venovenous extracorporeal membrane oxygenation (VV ECMO) support.

DESIGN

Retrospective observational cohort study.

SETTING

Adult patients in the Extracorporeal Life Support Organization registry.

PATIENTS

Thirteen thousand six hundred eighty-one patients that required ECMO for the support of ARDS between January 2012 and December 2022.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Mortality while supported with VV ECMO and survival to hospital discharge based on ECMO duration were examined utilizing multivariable logistic regression. Among the 13,681 patients supported with VV ECMO, 4,040 (29.5%) were supported for greater than or equal to 21 days and 975 (7.1%) for greater than or equal to 50 days. Patients supported with prolonged VV ECMO were less likely to be discharged alive from the hospital compared with those with short duration of support (46.5% vs. 59.7%; p < 0.001). However, among patients supported with VV ECMO greater than or equal to 21 days, duration of extracorporeal life support was not significantly associated with mortality (odds ratio [OR], 0.99; 95% CI, 0.98-1.01; p = 0.87 and adjusted OR, 0.99; 95% CI, 0.97-1.02; p = 0.48). Even in those supported with VV ECMO for at least 120 days (n = 113), 52 (46.0%) of these patients were ultimately discharged alive from the hospital.

CONCLUSIONS

Prolonged VV ECMO support of ARDS has increased and accounts for a substantial portion of cases. Among patients that survive for greater than or equal to 21 days while receiving VV ECMO support, duration is not predictive of survival to hospital discharge and clinical recovery may occur even after very prolonged VV ECMO support.

Derivation and validation of a noninvasive prediction tool to identify pulmonary hypertension in patients with IPF: Evolution of the model FORD

BACKGROUND

The administration of inhaled prostanoids to patients with pulmonary hypertension (PH) related to idiopathic pulmonary fibrosis (IPF) and other fibrotic lung diseases improves functional outcomes. Selection of patients with IPF at risk for concomitant PH to undergo right heart catheterization (RHC) remains challenging. We sought to develop a clinical prediction tool based on common noninvasive parameters to identify PH in patients with IPF.

METHODS

A prediction model based on noninvasive parameters was derived from patients enrolled in the ARTEMIS-IPF randomized, placebo-controlled clinical trial. Predictor variables were tested for association with the presence of PH diagnosed based on RHC. The derived multivariable logistic regression model and associated point-score index were then externally validated in a real-world cohort of patients with IPF.

RESULTS

Of the 481 patients included in the ARTEMIS-IPF study, 9.8% (N = 47) were diagnosed with PH related to IPF. Four variables were associated with PH and were included in the final model: forced vital capacity/diffusing capacity for carbon monoxide ratio (F), oxygen saturation nadir during 6-minute walk test (6MWT) (O), race (R), and distance ambulated during 6MWT (D). A model containing continuous predictors (FORD calculator) and a simple point-score system (FORD index) performed similarly well in the derivation cohort (area under the curve [AUC]: 0.75 and 0.75, respectively) and validation cohort (AUC: 0.69 and 0.69, respectively).

CONCLUSIONS

The FORD models are simple, validated tools incorporating noninvasive parameters that can be applied to identify patients at risk of PH related to IPF who may benefit from invasive testing.

Survival analysis from the INCREASE study in PH-ILD: evaluating the impact of treatment crossover on overall mortality

OBJECTIVE

A post-hoc analysis of the INCREASE trial and its open-label extension (OLE) was performed to evaluate whether inhaled treprostinil has a long-term survival benefit in patients with pulmonary hypertension associated with interstitial lung disease (PH-ILD).

METHODS

Two different models of survival were employed; the inverse probability of censoring weighting (IPCW) and the rank-preserving structural failure time (RPSFT) models both allow construction of a pseudo-placebo group, thereby allowing for long-term survival evaluation of patients with PH-ILD receiving inhaled treprostinil. Time-varying stabilised weights were calculated by fitting Cox proportional hazards models based on the baseline and time-varying prognostic factors to generate weighted Cox regression models with associated adjusted HRs.

RESULTS

In the INCREASE trial, there were 10 and 12 deaths in the inhaled treprostinil and placebo arms, respectively, during the 16-week randomised trial. During the OLE, all patients received inhaled treprostinil and there were 29 and 33 deaths in the prior inhaled treprostinil arm and prior placebo arm, respectively. With a conventional analysis, the HR for death was 0.71 (95% CI 0.46 to 1.10; p=0.1227). Both models demonstrated significant reductions in death associated with inhaled treprostinil treatment with HRs of 0.62 (95% CI 0.39 to 0.99; p=0.0483) and 0.26 (95% CI 0.07 to 0.98; p=0.0473) for the IPCW and RPSFT methods, respectively.

CONCLUSION

Two independent modelling techniques that have been employed in the oncology literature both suggest a long-term survival benefit associated with inhaled treprostinil treatment in patients with PH-ILD.

Antithrombotic Therapy for VTE Disease: Compendium and Review of CHEST Guidelines 2012-2021

The CHEST Antithrombotic Therapy for Venous Thromboembolism Disease evidence-based guidelines are now updated in a more frequent, focused manner. Guidance statements from the most recent full guidelines and two subsequent updates have not been gathered into a single source. An international panel of experts with experience in prior antithrombotic therapy guideline development reviewed the 2012 CHEST antithrombotic therapy guidelines and its two subsequent updates. All guideline statements and their associated patient, intervention, comparator, and outcome questions were assembled. A modified Delphi process was used to select statements considered relevant to current clinical care. The panel further endorsed minor phrasing changes to match the standard language for guidance statements using the modified Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) format endorsed by the CHEST Guidelines Oversight Committee. The panel appended comments after statements deemed as relevant, including suggesting that statements be updated in future guidelines because of interval evidence. We include 58 guidance statements from prior versions of the antithrombotic therapy guidelines, with updated phrasing as needed to adhere to contemporary nomenclature. Statements were classified as strong or weak recommendations based on high-certainty, moderate-certainty, and low-certainty evidence using GRADE methodology. The panel suggested that five statements are no longer relevant to current practice. As CHEST continues to update guidance statements relevant to antithrombotic therapy for VTE disease, this article serves as a unified collection of currently relevant statements from the preceding three guidelines. Suggestions have been made to update specific statements in future publications.

Hospitalization Rates in Interstitial Lung Disease: An Analysis of the Pulmonary Fibrosis Foundation Registry

RATIONALE

Little is known about hospitalization in other types of interstitial lung disease (ILD) besides idiopathic pulmonary fibrosis (IPF).

OBJECTIVES

We sought to determine the frequency of hospitalizations in various types of ILD and elucidate the association of hospitalization with outcomes.

METHODS

An analysis of the Pulmonary Fibrosis Foundation Patient Registry data was performed. Inpatient hospitalization rates and survival following hospitalization were compared for various types of ILD.

RESULTS

Hospitalization rates were similar across ILD types (40.6% of IPF participants, 42.8% of connective tissue disease related ILD (CTD-ILD), 44.9% of non-IPF idiopathic interstitial pneumonia (IIPs), 46.5% of chronic hypersensitivity pneumonitis (CHP) participants, and 53.3% of "other" ILD participants). All-cause hospitalization was not associated with decreased transplant-free survival (adjusted hazard ratio (AHR) 1.20, 95% CI: 0.98, 1.46, p=0.0759) after adjusting for co-morbidities and severity of illness; however respiratory-related hospitalization was (AHR 1.53, 95% CI: 1.23, 1.90, p=0.0001). CTD-ILD (HR 0.43, 95% CI: 0.25, 0.75, p=0.0031) and non-IPF IIP (HR 0.3, 95% CI: 0.15, 0.58, p=0.005) had a lower risk of death following hospitalization compared to IPF while CHP (HR 0.67, 95% CI: 0.37, 1.20, p=0.1747) and "other-ILD" (HR 0.54, 95% CI: 0.19, 1.54, p=0.25) had a comparable risk to IPF.

CONCLUSION

Rates of hospitalization are similar across ILD subtypes. The risk of death or transplant following hospitalization is lower in CTD-ILD, CHP and non-IPF IIP compared to IPF participants. In a mixed population of ILD participants, all-cause hospitalizations were not associated with decreased transplant-free survival; however respiratory-related hospitalizations were.

Pulmonary vascular dysfunction without pulmonary hypertension: A distinct phenotype in idiopathic pulmonary fibrosis

Pulmonary vascular dysfunction in the absence of pulmonary hypertension (PH) has been observed in patients with idiopathic pulmonary fibrosis (IPF). We describe the prevalence and etiology of elevated pulmonary vascular resistance (PVR) without PH among patients with IPF. Hemodynamic, echocardiographic, and functional respiratory imaging (FRI) data was compared between patients with IPF without PH with normal (<3 wood units) and elevated PVR (≥3 wood units). Mortality between these two groups were compared to patients with IPF and PH. Of 205 patients with IPF, there were 146 patients without PH, of whom 114 (78.1%) had a normal PVR and 32 (21.9%) who had a high PVR. Functional testing and hemodynamics were similar in the two groups, except for the cardiac index which was significantly lower in patients with a high PVR (2.3 vs. 2.6 L/min/m2; p = 0.004). Echocardiographic comparison demonstrated a higher tricuspid regurgitant velocity in those with a high PVR (3.4 vs 3.0 m/s; p = 0.046). FRI revealed proportionately fewer large vessels as a proportion of the vasculature in the patients without PH and elevated PVRs. Among patients without PH, PVR was associated with increased mortality. In conclusion, patients with IPF without PH but a high PVR appear to be a distinct phenotype with a prognosis between those with and without PH, likely reflecting the continuum of vascular dysfunction. The basis for this unique hemodynamic profile could not be definitively discerned although FRI suggested an aberrant anatomical vascular response.

Pulmonary Hypertension in Interstitial Lung Disease: Updates in Disease, Diagnosis, and Therapeutics

Pulmonary hypertension is a debilitating condition that frequently develops in the setting of interstitial lung disease, likely related to chronic alveolar hypoxemia and pulmonary vascular remodeling. This disease process is likely to be identified more frequently by providers given recent advancements in definitions and diagnostic modalities, and provides practitioners with emerging opportunities to improve patient outcomes and quality of life. Despite years of data suggesting against the efficacy of pulmonary vasodilator therapy in patients with pulmonary hypertension due to interstitial lung disease, new data have emerged identifying promising advancements in therapeutics. The authors present to you a comprehensive review of pulmonary hypertension in interstitial lung disease, reviewing our current understanding of pathophysiology, updates in diagnostic approaches, and highlights of recent clinical trials which provide an effective approach for medical management.

Factors associated with listing for lung transplantation in IPF patients: An analysis of the pulmonary fibrosis foundation registry

Rationale and objectives

Lung transplantation is a potentially life-saving treatment option for patients with idiopathic pulmonary fibrosis (IPF); however, not all eligible candidates get referred and listed for transplantation. Amongst IPF patients within the Pulmonary Fibrosis Foundation Patient Registry (PFF-R), we sought to determine the proportion of patients who undergo lung transplant listing and the characteristics associated with transplant listing.

Methods

An analysis of IPF patients with at least six months of follow-up data was performed. Patients with well-established contraindications to lung transplantation were excluded. Two complementary analyses were performed. The "prevalent" population included all patients with IPF at time of enrollment into the registry. The "incident severe" population included all patients with IPF who progressed to GAP Stage 3.

Results

Of the 2003 patients in the PFF-R, 475 patients were included in the "prevalent" population. Of this group, only 42 (8.8%) were either listed for or underwent lung transplant. Univariable analysis of the "prevalent" population found age (per 10 year increase, OR 0.531, p = 0.0025), percent predicted FVC (OR 0.572, p=<0.0001), percent predicted DLCO (OR 0.606, p < 0.0001), 6-min walk distance (per 50 m, OR 0.831, p = 0.019), and oxygen use at rest (OR 5.157, p < 0.0001) were predictive of listing. On multivariable analysis, age (per 10 year increase, OR 0.558, p = 0.0088), percent predicted FVC (OR 0.728, p = 0.0161), and oxygen use at rest (OR 3.264, p = 0.0029) remained significant predictors for lung transplant listing. The "incident severe" group consisted of 176 patients (8.8%). 24 patients (13.6%) from this cohort were either listed for or received a transplant. Only age (per 10 year increase, OR 0.0286, p = 0.0465) was associated with transplant listing on univariable analysis in the Incident severe population.

Conclusion

Only a small proportion of potentially eligible patients with IPF are listed for lung transplantation, even when seen at pulmonary fibrosis centers of excellence. Advanced age appears to be the primary factor associated with failure to be listed. Further refinement of future registry data is required to more clearly delineate exact reasons for low rates of listing.

Pulmonary Hypertension in Interstitial Lung Disease: Management Options to Move Beyond Supportive Care

Purpose of Review

This review delineates current diagnostic and management strategies for pulmonary hypertension due to interstitial lung disease (PH-ILD).

Recent Findings

The INCREASE trial, a phase III multicenter, randomized, placebo-controlled trial demonstrated both improved 6-min walk distance and decreased disease progression with inhaled treprostinil. This pivotal trial led to inhaled treprostinil becoming the first FDA approved medication for treatment of PH-ILD. The availability of this treatment has generated subsequent recommendations for the screening for PH in patients with ILD. As a result, it is becoming increasingly important for clinicians to gain awareness and familiarity with the evolving management options for PH-ILD.

Summary

The management of PH-ILD has its roots in goal-directed treatment of the underlying lung disease. However, recent medication advances and ongoing clinical studies are opening opportunities for more disease-specific treatment.

External validation and longitudinal application of the DO-GAP index to individualise survival prediction in idiopathic pulmonary fibrosis

Background

The Distance-Oxygen-Gender-Age-Physiology (DO-GAP) index has been shown to improve prognostication in idiopathic pulmonary fibrosis (IPF) compared to the Gender-Age-Physiology (GAP) score. We sought to externally validate the DO-GAP index compared to the GAP index for baseline risk assessment in patients with IPF. Additionally, we evaluated the utility of serial change in the DO-GAP index in predicting survival.

Methods

We performed an analysis of patients with IPF from the Pulmonary Fibrosis Foundation-Patient Registry (PFF-PR). Discrimination and calibration of the two models were assessed to predict transplant-free survival and IPF-related mortality. Joint longitudinal time-to-event modelling was utilised to individualise survival prediction based on DO-GAP index trajectory.

Results

There were 516 patients with IPF from the PFF-PR with available demographics, pulmonary function tests, 6-min walk test data and outcomes included in this analysis. The DO-GAP index (C-statistic: 0.73) demonstrated improved discrimination in discerning transplant-free survival compared to the GAP index (C-statistic: 0.67). DO-GAP index calibration was adequate, and the model retained predictive accuracy to identify IPF-related mortality (C-statistic: 0.74). The DO-GAP index was similarly accurate in the subset of patients taking antifibrotic medications. Serial change in the DO-GAP index improved model discrimination (cross-validated area under the curve: 0.83) enabling the personalised prediction of disease trajectory in individual patients.

Conclusion

The DO-GAP index is a simple, validated, multidimensional score that accurately predicts transplant-free survival in patients with IPF and can be adapted longitudinally in individual patients. The DO-GAP may also find use in studies of IPF to risk stratify patients and possibly as a clinical trial end-point.

Prevalence of pulmonary hypertension in patients with COVID-19 related lung disease listed for lung transplantation: A UNOS registry analysis

COVID-19 related lung disease (CRLD) has emerged as an indication for lung transplantation (LT) in highly select patients. The prevalence and prognostic implication of coexisting pulmonary hypertension (PH) in patients with CRLD listed for LT is not known. Adult patients in the United Network for Organ Sharing database listed for LT for COVID-19 related acute respiratory distress syndrome or fibrosis through March 2022 were identified. The prevalence and impact of precapillary PH on pre- and posttransplantation survival was determined. Time-to-event analysis was used to compare outcomes between those with and without precapillary PH. We identified 245 patients listed for LT for CRLD who had right heart catheterization data available at the time of registry listing. Median age of the cohort was 54 years (interquartile range [IQR]: 46, 60), 56 (22.9%) were female, and the median lung allocation score was 81.3 (IQR: 53.3, 89.4). The prevalence of precapillary PH at the time of transplant listing was 27.9%. There was no significant difference in pretransplant mortality in patients with and without precapillary PH (sHR: 0.5; 95% confidence interval [CI]: 0.1-1.7, p = 0.261). A total of 187 patients ultimately underwent LT; of those, 60 (31.0%) were identified as having precapillary PH during the waitlist period. Posttransplantation survival was similar between patients with and without pretransplant precapillary PH (hazard ratio: 0.96; 95% CI: 0.2-3.7, p = 0.953). We observed a high rate of concomitant precapillary PH in patients listed for LT for CRLD. Though common, coexisting precapillary PH was not associated with a significant difference in either pre- or post-transplantation outcomes.

Derivation and validation of a simple multidimensional index incorporating exercise capacity parameters for survival prediction in idiopathic pulmonary fibrosis

INTRODUCTION

The gender-age-physiology (GAP) index is an easy-to-use baseline mortality prediction model in idiopathic pulmonary fibrosis (IPF). The GAP index does not incorporate exercise capacity parameters such as 6 min walk distance (6MWD) or exertional hypoxia. We evaluated if the addition of 6MWD and exertional hypoxia to the GAP index improves survival prediction in IPF.

METHODS

Patients with IPF were identified at a tertiary care referral centre. Discrimination and calibration of the original GAP index were assessed. The cohort was then randomly divided into a derivation and validation set and performance of the GAP index with the addition of 6MWD and exertional hypoxia was evaluated. A final model was selected based on improvement in discrimination. Application of this model was then evaluated in a geographically distinct external cohort.

RESULTS

There were 562 patients with IPF identified in the internal cohort. Discrimination of the original GAP index was measured by a C-statistic of 0.676 (95% CI 0.635 to 0.717) and overestimated observed risk. 6MWD and exertional hypoxia were strongly predictive of mortality. The addition of these variables to the GAP index significantly improved model discrimination. A revised index incorporating exercise capacity parameters was constructed and performed well in the internal validation set (C-statistic: 0.752; 95% CI 0.701 to 0.802, difference in C-statistic compared with the refit GAP index: 0.050; 95% CI 0.004 to 0.097) and external validation set (N=108 (C-statistic: 0.780; 95% CI 0.682 to 0.877)).

CONCLUSION

A simple point-based baseline-risk prediction model incorporating exercise capacity predictors into the original GAP index may improve prognostication in patients with IPF.

Inhaled Treprostinil Dosage in Pulmonary Hypertension Associated With Interstitial Lung Disease and Its Effects on Clinical Outcomes

BACKGROUND

Pulmonary hypertension (PH) complicates the course of many patients with fibrotic interstitial lung disease (ILD). Inhaled treprostinil (iTre) has been shown to improve functional ability and to delay clinical worsening in patients with PH resulting from ILD.

RESEARCH QUESTION

Do higher dosages of iTre have greater benefits in preventing clinical worsening and achieving clinical improvement?

STUDY DESIGN AND METHODS

Post hoc analysis of the INCREASE study, a 16-week double-blind, randomized, placebo-controlled trial of iTre in patients with PH resulting from ILD. Four groups were identified based on the number of breaths per session (bps; < 9 and ≥ 9 bps) of active drug or placebo attained at 4 weeks. Patients were evaluated for clinical worsening (15% decrease in 6-min walkdistance, cardiopulmonary hospitalization, lung transplantation, or death) or clinical improvement (15% increase in the six-minute walk distance with a concomitant 30% reduction in N-terminal prohormone of brain natriuretic peptide without any clinical worsening event).

RESULTS

At 4 weeks, 70 patients were at a dose of ≥ 9 bps (high-dosage group) and 79 patients were at a dose of < 9 bps (low-dosage group) in the iTre arm vs 86 patients in the high-dose group and 67 patients in the low-dose group in the placebo arm. Between weeks 4 and 16, 17.1% of patients in the high-dose treprostinil group and 22.8% in the low-dose treatment group experienced a clinical worsening event vs 33.7% and 34.3% of patients in the two placebo arms, respectively (P = .006). By week 16, 15.7% and 12.7% of patients in the high- and low-dose iTre groups, respectively, demonstrated clinical improvement vs 7% and 1.5% patients in the placebo arms (P = .003) INTERPRETATION: Higher dosages of iTre overall show greater benefit in terms of preventing clinical worsening and achieving clinical improvement. These data support the early initiation and uptitration of therapy to a dosage of at least 9 bps four times daily in patients with PH resulting from ILD.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02630316; URL: www.

CLINICALTRIALS

gov.

ACR Appropriateness Criteria® Suspected Pulmonary Hypertension: 2022 Update

Pulmonary hypertension may be idiopathic or related to a large variety of diseases. Various imaging examinations may be helpful in diagnosing and determining the etiology of pulmonary hypertension. Imaging examinations discussed in this document include chest radiography, ultrasound echocardiography, ventilation/perfusion scintigraphy, CT, MRI, right heart catheterization, and pulmonary angiography. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Agreement Between the TEG 6s and TEG 5000 Analyzers in Extracorporeal Membrane Oxygenation

Thromboelastography (TEG) evaluates viscoelastic properties of blood clot formation. The TEG 5000 analyzer is commonly used but prone to errors related to vibration or operator error. The TEG 6s was developed to overcome these limitations. Performance of TEG 6s compared with TEG 5000 has not been reported in extracorporeal membrane oxygenation (ECMO). We compared the agreement between devices via a single-center prospective observational study in hospitalized adult patients on ECMO. Data for both devices were collected daily for 3 days after ECMO initiation. Standard tests for method comparison were used. Thirty-four matching samples were available for analysis. Minimal bias was noted; however, the limit of agreement was wide for TEG parameters. Visually, agreement was better for values within the reference ranges of the tests. Lin's coefficients demonstrated moderate correlation for reaction time and alpha angle (0.58; 95% confidence interval [CI], 0.31-0.76 and 0.63; 95% CI, 0.40-0.78, respectively). Excellent correlation was demonstrated for kinetic time and maximum amplitude (0.88; 95% CI, 0.79-0.94 and 0.89; 95% CI, 0.79-0.94). The TEG 6s device may represent an acceptable surrogate for the TEG 5000 in patients on ECMO. However, limitations in reliability were noted, and the devices may not be interchangeable when results fall outside of the reference values.

Lung Transplantation for Patients With COVID-19

The COVID-19 pandemic has caused acute lung injury in millions of individuals worldwide. Some patients develop COVID-related acute respiratory distress syndrome (CARDS) and cannot be liberated from mechanical ventilation. Others may develop post-COVID fibrosis, resulting in substantial disability and need for long-term supplemental oxygen. In both of these situations, treatment teams often inquire about the possibility of lung transplantation. In fact, lung transplantation has been successfully employed for both CARDS and post-COVID fibrosis in a limited number of patients worldwide. Lung transplantation after COVID infection presents a number of unique challenges that transplant programs must consider. In those with severe CARDS, the inability to conduct proper psychosocial evaluation and pretransplantation education, marked deconditioning from critical illness, and infectious concerns regarding viral reactivation are major hurdles. In those with post-COVID fibrosis, our limited knowledge about the natural history of recovery after COVID-19 infection is problematic. Increased knowledge of the likelihood and degree of recovery after COVID-19 acute lung injury is essential for appropriate decision-making with regard to transplantation. Transplant physicians must weigh the risks and benefits of lung transplantation differently in a post-COVID fibrosis patient who is likely to remain stable or gradually improve in comparison with a patient with a known progressive fibrosing interstitial lung disease (fILD). Clearly lung transplantation can be a life-saving therapeutic option for some patients with severe lung injury from COVID-19 infection. In this review, we discuss how lung transplant providers from a number of experienced centers approach lung transplantation for CARDS or post-COVID fibrosis.

Inhaled Nitric Oxide via High-Flow Nasal Cannula in Patients with Acute Respiratory Failure Related to COVID-19

INTRODUCTION

Limited evidence exists regarding use of inhaled nitric oxide (iNO) in spontaneously breathing patients. We evaluated the effectiveness of continuous iNO via high-flow nasal cannula (HFNC) in COVID-19 respiratory failure.

METHODS

We performed a multicenter cohort study of patients with respiratory failure from COVID-19 managed with HFNC. Patients were stratified by administration of iNO via HFNC. Regression analysis was used to compare the need for mechanical ventilation and secondary endpoints including hospital mortality, length of stay, acute kidney injury, need for renal replacement therapy, and need for extracorporeal life support.

RESULTS

A total of 272 patients were identified and 66 (24.3%) of these patients received iNO via HFNC for a median of 88 h (interquartile range: 44, 135). After 12 h of iNO, supplemental oxygen requirement was unchanged or increased in 52.7% of patients. Twenty-nine (43.9%) patients treated with iNO compared to 79 (38.3%) patients without iNO therapy required endotracheal intubation (P = .47). After multivariable adjustment, there was no difference in need for mechanical ventilation between groups (odds ratio: 1.53; 95% confidence interval [CI]: 0.74-3.17), however, iNO administration was associated with longer hospital length of stay (incidence rate ratio: 1.41; 95% CI: 1.31-1.51). No difference was found for mortality, acute kidney injury, need for renal replacement therapy, or need for extracorporeal life support.

CONCLUSION

In patients with COVID-19 respiratory failure, iNO delivered via HFNC did not reduce oxygen requirements in the majority of patients or improve clinical outcomes. Given the observed association with increased length of stay, judicious selection of those likely to benefit from this therapy is warranted.

Fostamatinib for the Treatment of Hospitalized Adults With Coronavirus Disease 2019: A Randomized Trial

BACKGROUND

Coronavirus disease 2019 (COVID-19) requiring hospitalization is characterized by robust antibody production, dysregulated immune response, and immunothrombosis. Fostamatinib is a novel spleen tyrosine kinase inhibitor that we hypothesize will ameliorate Fc activation and attenuate harmful effects of the anti-COVID-19 immune response.

METHODS

We conducted a double-blind, randomized, placebo-controlled trial in hospitalized adults requiring oxygen with COVID-19 where patients receiving standard of care were randomized to receive fostamatinib or placebo. The primary outcome was serious adverse events by day 29.

RESULTS

A total of 59 patients underwent randomization (30 to fostamatinib and 29 to placebo). Serious adverse events occurred in 10.5% of patients in the fostamatinib group compared with 22% in placebo (P = .2). Three deaths occurred by day 29, all receiving placebo. The mean change in ordinal score at day 15 was greater in the fostamatinib group (-3.6 ± 0.3 vs -2.6 ± 0.4, P = .035) and the median length in the intensive care unit was 3 days in the fostamatinib group vs 7 days in placebo (P = .07). Differences in clinical improvement were most evident in patients with severe or critical disease (median days on oxygen, 10 vs 28, P = .027). There were trends toward more rapid reductions in C-reactive protein, D-dimer, fibrinogen, and ferritin levels in the fostamatinib group.

CONCLUSION

For COVID-19 requiring hospitalization, the addition of fostamatinib to standard of care was safe and patients were observed to have improved clinical outcomes compared with placebo. These results warrant further validation in larger confirmatory trials.

CLINICAL TRIALS REGISTRATION

Clinicaltrials.gov, NCT04579393.

Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report - Executive Summary

BACKGROUND

This is the second update to the 9^th edition of these guidelines. We provide recommendations on 17 PICO (Patients, Interventions, Comparators, Outcomes) questions, four of which have not been addressed previously.

METHODS

We generate strong and weak recommendations based on high, moderate, and low-certainty evidence, using GRADE methodology.

RESULTS

The panel generated 29 guidance statements, 13 of which are graded as strong recommendations, covering aspects of antithrombotic management of venous thromboembolism from initial management through secondary prevention and risk reduction of post-thrombotic syndrome. Four new guidance statements are added that did not appear in the 9^th edition (2012) or first update (2016). Eight statements have been substantially modified from the first update.

CONCLUSION

New evidence has emerged since 2016 which further informs the standard of care for patients with venous thromboembolism. Substantial uncertainty remains regarding important management questions, particularly in limited disease and special patient populations.

High-Flow Nasal Cannula Therapy in COVID-19: Using the ROX Index to Predict Success

BACKGROUND

Optimal timing of mechanical ventilation in COVID-19 is uncertain. We sought to evaluate outcomes of delayed intubation and examine the ROX index (ie, [[Formula: see text]]/breathing frequency) to predict weaning from high-flow nasal cannula (HFNC) in patients with COVID-19.

METHODS

We performed a multicenter, retrospective, observational cohort study of subjects with respiratory failure due to COVID-19 and managed with HFNC. The ROX index was applied to predict HFNC success. Subjects that failed HFNC were divided into early HFNC failure (≤ 48 h of HFNC therapy prior to mechanical ventilation) and late failure (> 48 h). Standard statistical comparisons and regression analyses were used to compare overall hospital mortality and secondary end points, including time-specific mortality, need for extracorporeal membrane oxygenation, and ICU length of stay between early and late failure groups.

RESULTS

272 subjects with COVID-19 were managed with HFNC. One hundred sixty-four (60.3%) were successfully weaned from HFNC, and 111 (67.7%) of those weaned were managed solely in non-ICU settings. ROX index >3.0 at 2, 6, and 12 hours after initiation of HFNC was 85.3% sensitive for identifying subsequent HFNC success. One hundred eight subjects were intubated for failure of HFNC (61 early failures and 47 late failures). Mortality after HFNC failure was high (45.4%). There was no statistical difference in hospital mortality (39.3% vs 53.2%, P = .18) or any of the secondary end points between early and late HFNC failure groups. This remained true even when adjusted for covariates.

CONCLUSIONS

In this retrospective review, HFNC was a viable strategy and mechanical ventilation was unecessary in the majority of subjects. In the minority that progressed to mechanical ventilation, duration of HFNC did not differentiate subjects with worse clinical outcomes. The ROX index was sensitive for the identification of subjects successfully weaned from HFNC. Prospective studies in COVID-19 are warranted to confirm these findings and to optimize patient selection for use of HFNC in this disease.

Incidence and prognostic significance of pleural effusions in pulmonary arterial hypertension

It has been suggested pleural effusions may develop in right heart failure in the absence of left heart disease. The incidence and prognostic significance of pleural effusions in pulmonary arterial hypertension is uncertain. Patients with pulmonary arterial hypertension followed at our tertiary care center were reviewed. Survival was examined based on the subsequent development of a pleural effusion. A total of 191 patients with pulmonary arterial hypertension met the inclusion criteria. The prevalence of pleural effusions on initial assessment was 7.3%. Among patients without a pleural effusion on initial imaging and at least one follow-up computerized tomography (N = 142), pleural effusion developed in 27.5% (N = 39) of patients. No alternative etiology of the effusion was identified in 19 (48.7%) cases and effusions deemed related to pulmonary arterial hypertension occurred at an incident rate of 38.6 cases per 1000 person-years. Of these, 14 (73.7%) were bilateral, 3 (15.8%) were right-sided, and 2 (10.5%) were left-sided. Effusion size was trace or small in 18 patients (94.7%). Development of a new pleural effusion was associated with attenuated survival in unadjusted survival analysis (HR: 3.80; 95% CI: 1.55–9.31), multivariate analysis (HR: 5.13; 95% CI: 1.86–14.16), and after the multivariate model was adjusted for concomitant pericardial effusion (HR: 4.86; 95% CI: 1.51–15.71). Negative impact on survival remained unchanged when effusions more likely related to an alternative cause were removed from analysis. In conclusion, pleural effusions can complicate pulmonary arterial hypertension in the absence of left heart disease. These effusions are frequently small in size, bilateral in location, and their presence is associated with decreased survival. Attenuated survival appears independent of the risk associated with a new pericardial effusion.

Impact of the new definition for pulmonary hypertension in patients with lung disease: an analysis of the United Network for Organ Sharing database

The implications of the recent change in the definition of pulmonary hypertension on epidemiology and outcomes are not known. We sought to determine the percentage of patients with the two most common lung diseases that would be reclassified regarding the presence/absence of pulmonary hypertension with the revised definition. A query of the United Network for Organ Sharing database was performed. The percentage of patients meeting the current and previous definition of pulmonary hypertension was described. Outcomes of patients stratified by the current and previous definitions were compared. There were 15,563 patients with right heart catheterization data analyzed. Pulmonary hypertension was more prevalent in both chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis under the new definition at 52.4% versus 82.4%, and 47.6% versus 73.6%, respectively. “Pre-capillary” pulmonary hypertension by the new definition was lower at 28.1% for chronic obstructive pulmonary disease and 36.8% for idiopathic pulmonary fibrosis. Of the patients with pulmonary hypertension by the old definition, 23.9% of chronic obstructive pulmonary disease patients and 18.7% of idiopathic pulmonary fibrosis patients were not classified as pulmonary hypertension by the new definition. Conversely, 15.9% of chronic obstructive pulmonary disease patients and 15.1% of idiopathic pulmonary fibrosis patients who did not meet diagnostic criteria for pulmonary hypertension by the old definition did have pulmonary hypertension by the new definition. Patients in both disease categories had shorter transplant-free waitlist survival in the presence of pulmonary hypertension by both the new and old definitions. There was a trend toward the new definition of pre-capillary pulmonary hypertension better discerning outcomes compared to the old definition of pulmonary hypertension in idiopathic pulmonary fibrosis patients. Most patients with advanced lung disease who are listed for lung transplantation have pulmonary hypertension, but fewer have pre-capillary pulmonary hypertension than pulmonary hypertension by the old definition. Both the old and new definition of precapillary pulmonary hypertension appear to discern outcomes among the two groups of lung disease analyzed, with some evidence to suggest that the new definition performs slightly better in the idiopathic pulmonary fibrosis population.

Association of D-dimer and Fibrinogen With Hypercoagulability in COVID-19 Requiring Extracorporeal Membrane Oxygenation

BACKGROUND

D-dimer concentration has been used by institutions to identify candidates for intensified anticoagulant treatment for venous thromboembolism prevention and for the mitigation of the microthrombotic complications associated with COVID-19. Thromboelastography (TEG) maximum amplitude (MA) has been validated as a marker of hypercoagulability and MA ≥68 mm has been utilized as a marker of hypercoagulability in other conditions.

METHODS

The goal of this study was to evaluate the relationship between coagulation, inflammatory, and TEG parameters in patients with COVID-19 on extracorporeal membrane oxygenation (ECMO). We performed a single-center retrospective analysis of consecutive patients that received ECMO for the treatment of COVID-19. TEG, inflammatory, and coagulation markers were compared in patients with and without a thrombotic complication. Correlation tests were performed to identify the coagulation and inflammatory markers that best predict hypercoagulability as defined by an elevated TEG MA.

RESULTS

A total of 168 TEGs were available in 24 patients. C-reactive protein and fibrinogen were significantly higher in patients that developed a thrombotic event versus those that did not (P = 0.04 and P = 0.04 respectively). D-dimer was negatively correlated with TEG MA (P < 0.01), while fibrinogen was positively correlated (P < 0.01). A fibrinogen >441 mg/dL was found to have a sensitivity of 91.2% and specificity of 85.7% for the detection of MA ≥68 mm.

CONCLUSIONS

In critically ill patients with COVID-19 treated with ECMO, D-dimer concentration had an inverse relationship with degree of hypercoagulability as measured by TEG MA. D-dimer elevation may potentially reflect hemostatic perturbation in patients on ECMO or the severity of COVID-19 related sepsis rather than designate patients likely to benefit from anticoagulation. Fibrinogen concentration may represent a more useful marker of hypercoagulability in this population.

Idiopathic pulmonary fibrosis patients with severe physiologic impairment: characteristics and outcomes

RESEARCH QUESTION

There is no widely accepted grading system for IPF disease severity, although physiologic impairment based on pulmonary function testing is frequently employed. We sought to describe clinical and functional characteristics as well as outcomes of patients with severe physiologic impairment.

PATIENTS AND METHODS

IPF patients with severe physiologic impairment defined by FVC ≤ 50% and/or DLco ≤ 30% predicted evaluated in the Inova Advanced Lung Disease Program between 2011 and 2019 were included. Demographic, physiologic, functional treatment and outcome data were collated.

RESULTS

There were 531 patients with IPF evaluated of whom 242 (46%) had severe physiologic impairment. Mean age was 72 ± 8 years; baseline FVC was 53 ± 17% and DL_CO 28 ± 9% of predicted. The mean 6 min walks test (6MWT) distance was 304 ± 121 m with 59% of the patients requiring supplemental oxygen ([Formula: see text] group). There was a poor correlation between the 6MWT distance and both FVC% and DLco%. Patients in the 6MWT_RA group had a better transplant-free survival than the [Formula: see text] group (p = 0.002). Patients managed before October 2014 and not receiving antifibrotic therapy had worse outcomes with reduced transplant-free survival compared with patients presenting after this date who did receive antifibrotic therapy (n = 113) (log rank p < 0.0001).

CONCLUSION

IPF patients often present with severe physiologic impairment which may be poorly correlated with their functional status. Assessment of IPF disease severity should not be based on physiologic impairment alone, but should also encompass functional status as well as need for supplemental oxygen. Antifibrotic therapy in patients with severe physiologic impairment is associated with improved outcomes.

Outcomes of mechanically ventilated patients with COVID-19 associated respiratory failure

Purpose

The outcomes of patients requiring invasive mechanical ventilation for COVID-19 remain poorly defined. We sought to determine clinical characteristics and outcomes of patients with COVID-19 managed with invasive mechanical ventilation in an appropriately resourced US health care system.

Methods

Outcomes of COVID-19 infected patients requiring mechanical ventilation treated within the Inova Health System between March 5, 2020 and April 26, 2020 were evaluated through an electronic medical record review.

Results

1023 COVID-19 positive patients were admitted to the Inova Health System during the study period. Of these, 164 (16.0%) were managed with invasive mechanical ventilation. All patients were followed to definitive disposition. 70/164 patients (42.7%) had died and 94/164 (57.3%) were still alive. Deceased patients were older (median age of 66 vs. 55, p <0.0001) and had a higher initial d-dimer (2.22 vs. 1.31, p = 0.005) and peak ferritin levels (2998 vs. 2077, p = 0.016) compared to survivors. 84.3% of patients over 70 years old died in the hospital. Conversely, 67.4% of patients age 70 or younger survived to hospital discharge. Younger age, non-Caucasian race and treatment at a tertiary care center were all associated with survivor status.

Conclusion

Mortality of patients with COVID-19 requiring invasive mechanical ventilation is high, with particularly daunting mortality seen in patients of advanced age, even in a well-resourced health care system. A substantial proportion of patients requiring invasive mechanical ventilation were not of advanced age, and this group had a reasonable chance for recovery.

Association Between Anticoagulation and Survival in Interstitial Lung Disease: An Analysis of the Pulmonary Fibrosis Foundation Patient Registry

BACKGROUND

Aberrations in the coagulation system have been implicated in the pathogenesis of interstitial lung disease (ILD). Anticoagulants have been proposed as a potential therapy in ILD; however, a randomized controlled trial examining warfarin as a treatment for IPF was terminated early due to increased death rates. This has led some to speculate that warfarin specifically may be harmful in ILD, and use of direct oral anticoagulants (DOACs) could result in superior outcomes.

RESEARCH QUESTION

The goal of this study was to delineate the relationship between anticoagulation and outcomes in patients with ILD through an analysis of the Pulmonary Fibrosis Foundation Patient Registry.

STUDY DESIGN AND METHODS

An analysis of all patients in the Pulmonary Fibrosis Foundation Patient Registry was performed. Patients were stratified into three groups: no anticoagulation, DOAC use, or warfarin use. Survival was analyzed by using both Kaplan-Meier curves and Cox proportional hazards models.

RESULTS

Of 1,911 patients included in the analysis, 174 (9.1%) were given anticoagulants; 93 (4.9%) received DOACs, and 81 (4.2%) received warfarin. There was a twofold increased risk of death or transplant for patients receiving DOACS; for warfarin, the risk was over two and half times greater. DOACs were not associated with an increased risk of mortality following adjustment for confounding variables. However, even after adjustment, patients given the anticoagulant warfarin remained at increased risk of mortality. In patients with IPF, warfarin was associated with reduced transplant-free survival, but DOACs were not. There was no statistically significant difference in survival between those receiving warfarin and those receiving a DOAC.

INTERPRETATION

The need for anticoagulation is associated with an increased risk for death or transplant in patients with ILD, in both the IPF and non-IPF population. Further research is required to determine if warfarin and DOACs present varying safety profiles in patients with ILD.

Expert consensus on the management of adverse events and prescribing practices associated with the treatment of patients taking pirfenidone for idiopathic pulmonary fibrosis: a Delphi consensus study

Background

In patients with idiopathic pulmonary fibrosis (IPF) treated with pirfenidone (Esbriet®, Genentech USA, Inc. South San Francisco, CA.), effectively managing treatment-related adverse events (AEs) may improve adherence. Due to a lack of clinical evidence and expertise, managing these AEs can be challenging for patients and physicians alike. In the absence of evidence, consensus recommendations from physicians experienced in using pirfenidone to treat IPF are beneficial.

Methods

Using a modified Delphi process, expert recommendations were developed by a panel of physicians experienced with using pirfenidone for IPF. Over three iterations, panelists developed and refined a series of statements on the use of pirfenidone in IPF. Their agreement on each statement was ranked using a Likert scale.

Results

A panel of 12 physicians participated and developed a total of 286 statements on dosing and administration, special populations, drug-drug interactions, laboratory analysis, warnings and precautions, and AE management. Expert recommendations were achieved with regard to slower initial titrations and slower titrations for AEs, dosing with meal(s) or substantial meals, and adding other prescribed pharmacological agents for AEs.

Conclusion

Until there is further clinical evidence, the resulting consensus recommendations are intended to provide direction on the practical management of IPF with pirfenidone, by encompassing a broad experience from the real world to complement data gleaned from clinical trials.

The association between white blood cell count and outcomes in patients with idiopathic pulmonary fibrosis

BACKGROUND

The course of idiopathic pulmonary fibrosis (IPF) is uncertain with variable patterns of disease progression. We sought to evaluate the prognostic utility of the WBC, a routinely performed lab test, in a well-defined cohort of outpatient IPF subjects.

METHODS

We reviewed IPF patient records from two independent ILD centers (Inova Fairfax in Falls Church, VA, USA and Ege University Hospital in Izmir, Turkey) between 2007 and 2018. Demographics, CBC data, and patient outcomes were obtained. Survival differences were analyzed.

RESULTS

There were 436 IPF outpatients in the cohort with a median WBC of 8.9 × 10⁹ cells per liter. For pragmatic purposes, patients were categorized into two groups, WBC ≥9 or WBC <9. Patients with WBC <9 had a median transplant-free survival of 50.5 months from the time of the CBC, compared to 32.4 months for those with WBC ≥9 (p < 0.0001). The association between WBC and attenuated survival remained significant after adjusting for GAP stage, steroid use, and antifibrotic use when WBC was analyzed both as a continuous (HR: 1.11; 95% CI: 1.05-1.17) and a dichotomized variable (high (WBC ≥9) vs. low (WBC <9), (HR: 1.53; 95% CI:1.09-2.15). WBC and absolute neutrophil count (ANC) were highly correlated suggesting that PMNs account for most of this association (r = 0.92).

CONCLUSIONS

Baseline WBC may impart important and readily available prognostic information in outpatients with IPF. Further studies are warranted to validate this as a potential biomarker for IPF, as well as to define the biologic basis for the association.

The Trouble With Group 3 Pulmonary Hypertension in Interstitial Lung Disease: Dilemmas in Diagnosis and the Conundrum of Treatment

Pulmonary hypertension (PH) due to interstitial lung disease (ILD; PH-ILD) can complicate a multitude of ILDs, including idiopathic pulmonary fibrosis, chronic hypersensitivity pneumonitis, and nonspecific interstitial pneumonia. Development of PH-ILD is associated with increased need for supplemental oxygen, reduced mobility, and decreased survival. A high index of suspicion is required to make the diagnosis, given the substantial overlap in symptoms with those of ILD without PH. Severely reduced diffusing capacity or 6-min walk test distance, prominent exertional desaturation, and impaired heart rate recovery after exercise are all suggestive of the development of PH-ILD. Traditional transthoracic echocardiography is the most commonly used screening test for PH-ILD, but it lacks sensitivity and specificity. Newer echocardiographic tools involving 3-dimensional assessment of the right ventricle may have a role in both prognosis and the monitoring of patients with PH-ILD. Right-sided heart catheterization remains the gold standard for confirming a diagnosis of PH-ILD. Although there is little debate about the use of supplemental oxygen and diuretic therapy in the treatment of PH-ILD, treatment with pulmonary vasodilator therapy remains controversial. Although several studies have been terminated prematurely for harm, the recently completed INCREASE trial of inhaled treprostinil appears to validate the concept of treating PH-ILD with pulmonary vasodilators and, we hope, will serve as a foundation from which future studies can be developed.

A 24-Year-Old Woman With Precipitous Respiratory Failure After Lung Transplantation

CASE PRESENTATION

A 24-year-old woman with ΔF508/Y1092X cystic fibrosis (CF) complicated by severe obstructive lung disease (FEV₁ of 30% predicted) was admitted for IV antibiotics for planned sinus surgery resulting from severe chronic sinusitis causing frequent exacerbations and declining lung function. She had persistent airway infection with multidrug-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and growth of a fungus presumed to be an airway colonizer, identified as Stephanoascus ciferrii 1 year before presentation. Two days after surgery, she developed acute respiratory failure requiring mechanical ventilation. On day 4 of mechanical ventilation, venovenous-extracorporeal membrane oxygenation (VV-ECMO) was initiated for refractory respiratory failure. The following day, she was listed for bilateral lung transplant and was transplanted 4 days later. Following transplantation, she was decannulated from ECMO; however, over the next 12 hours, oxygenation deteriorated requiring reinstitution of VV-ECMO for presumed severe primary graft dysfunction. Despite treatment with broad spectrum antimicrobial coverage with piperacillin/tazobactam, ciprofloxacin, linezolid, micafungin, voriconazole, and ganciclovir, she failed to improve and developed complex bilateral pleural effusions.

Pulmonary hypertension due to interstitial lung disease

PURPOSE OF REVIEW

Pulmonary hypertension has been reported to complicate the course of a number of fibrotic lung diseases, including idiopathic pulmonary fibrosis, chronic hypersensitivity pneumonitis and nonspecific interstitial pneumonitis. Most commonly, mild elevations in the mean pulmonary artery pressure are seen in patients with advanced pulmonary fibrosis. However, some patients may develop severe pulmonary hypertension, which appears out of proportion to the degree of their restrictive lung disease.

RECENT FINDINGS

The benefits of pulmonary vasodilator therapy have yet to be established in pulmonary hypertension complicating fibrotic lung disease. In fact, one recent clinical trial examining riociguat in patients with pulmonary hypertension complicating idiopathic interstitial pneumonias was terminated early for an increased risk of death or hospitalization. Multiple clinical trials on this topic are currently ongoing, including studies examining inhaled pulmonary vasodilator therapies.

SUMMARY

The development of pulmonary hypertension is associated with increased exertional oxygen requirements, worsened functional capacity and attenuated life expectancy. It is hoped that continued research will find an effective therapy for this condition, which will improve quality of life and extend life expectancy in patients with this condition.

Extracorporeal Membrane Oxygenation as a Bridge to Initial Medical Therapy in a Patient With Decompensated Pulmonary Arterial Hypertension Presenting With Biventricular Failure

Extracorporeal membrane oxygenation (ECMO) can be used as a bridge to medical therapy in decompensated right heart failure due to pulmonary arterial hypertension (PAH). A middle-aged man with previously undiagnosed pulmonary hypertension was successfully bridged to intravenous prostanoid therapy with venoarterial ECMO support after presenting with cardiogenic shock and hypoxemic respiratory failure. Although the patient initially had biventricular failure, PAH was suspected due to underlying mixed connective tissue disease and disproportionate right ventricular dysfunction. On occasion, patients with PAH may present with biventricular failure. A high index of suspicion for PAH and serial reassessment of left ventricular function following correction of shock may demonstrate improvement in left ventricular function, allowing for initiation of pulmonary vasodilator therapy.

Cardiac Support: Emphasis on Venoarterial ECMO

Major advances have been made in mechanical circulatory support in recent years. Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) provides both pulmonary and circulatory support for critically ill patients with hemodynamic compromise, serving as a bridge to recovery or definitive therapy in the form of transplant or a durable ventricular assist device. In the past, VA ECMO support was used in cases of cardiogenic shock or failure to wean from cardiopulmonary bypass; however, the technology is now being applied to an ever-expanding list of conditions, including massive pulmonary embolism, cardiac arrest, drug overdose, and hypothermia.

Early postoperative management after lung transplantation: Results of an international survey

INTRODUCTION

Little data exist regarding optimal therapeutic strategies postoperatively after lung transplant (LTx). Current practice patterns rely on expert opinion and institutional experience resulting in nonuniform postoperative care. To better define current practice patterns, an international survey of LTx clinicians was conducted.

METHODS

A 30-question survey was sent to transplant clinicians via email to the International Society of Heart and Lung Transplantation open forum mailing list and directly to the chief transplant surgeon and pulmonologist of all LTx centers in the United States.

RESULTS

Fifty-two clinicians representing 10 countries responded to the survey. Sedatives use patterns included: opiates + propofol (57.2%), opiates + dexmedetomidine (18.4%), opiates + intermittent benzodiazepines (14.3%), opiates + continuous benzodiazepines (8.2%), and opiates alone (2%). About 40.4% reported no formal sedation scale was followed and 13.5% of programs had no formal policy on sedation and analgesia. A lung protective strategy was commonly employed, with 13.8%, 51.3%, and 35.9% of respondents using tidal volumes of <6 mL/kg ideal body weight (IBW), 6 mL/kg IBW, and 8 mL/kg IBW, respectively.

CONCLUSION

Practice patterns in the early postoperative care of lung transplant recipients differ considerably among centers. Many of the reported practices do not conform to consensus guidelines on management of critically ill patients.

Ventricular Diastolic Pressure Ratio as a Marker of Treatment Response in Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is diagnosed and classified through right-sided heart catheterization, with a number of hemodynamic markers used to help guide treatment decisions. These markers may not reflect the complex remodeling of the right ventricle or the interplay between ventricles and struggle to predict treatment response. This study investigates the use of a novel marker: the ratio of left ventricular end-diastolic pressure to right ventricular end-diastolic pressure (LVEDP/RVEDP) in predicting treatment outcomes in a cohort of patients with PH.

METHODS

We performed a retrospective analysis of patients with PH at INOVA Fairfax Hospital's advanced lung disease program with simultaneous left-sided and right-sided heart catheterization. The primary end point was the time to clinical improvement, defined by an improvement in distance walked on the 6-min walk test (6MWT) of > 35 m in a year without interceding hospitalization for worsening PH or the need for additional PH therapy.

RESULTS

A total of 51 patients were included in the final analysis, 21 of whom (41.2%) had a salutary treatment effect with a mean improvement in the 6MWT of 75 m. Treatment responders were more likely to have a lower LVEDP/RVEDP ratio (1.08 vs 1.62; P = .051). This association persisted in the final multivariate regression model after adjustment for age and sex and controlling for severity of PH (OR, 0.17; 95% CI, 0.03-0.65; P = .024).

CONCLUSIONS

The LVEDP/RVEDP ratio is a novel marker for therapeutic response in patients with PH treated with pulmonary vasodilator medications and may offer robust predictive value independent of existing markers of disease severity.

Hemothorax following lung transplantation: incidence, risk factors, and effect on morbidity and mortality

Background: Hemothorax after lung transplantation may result in increased post-operative morbidity and mortality. Risk factors for developing hemothorax and the outcomes of patients who develop hemothorax have not been well studied. Methods: A retrospective chart review was performed on all patients who underwent lung transplantation at a single center between March 2009 and July 2014. Comparison was made between patients with and without hemothorax post-transplant. Results: There were 132 lung transplantations performed during the study period. Hemothorax was a complication in 17 (12.9 %) patients, occurring an average of 9 days after transplant. No difference was found between the hemothorax and non-hemothorax groups with respect to age, preoperative anticoagulation, lung allocation score, prior thoracotomy, coagulation profile, use of cardiopulmonary bypass, ischemic time, or postoperative P/F ratio. There was a trend towards a higher incidence of hemothorax in patients with underlying sarcoidosis and re-transplantation (p = 0.13 and 0.17, respectively). Hemothorax developed early (<48 h post-operatively) in 5 patients and presented in a delayed manner (≥48 h post-operatively) in 12 patients. Delayed hemothorax occurred primarily in the setting of anticoagulation (10 out of 12 patients). The hemothorax group had decreased ventilator-free days (p = 0.006), increased ICU length of stay (p = 0.01) and increased hospital length of stay (p = 0.005). Hemothorax was also associated with reduced 90-day survival (p = 0.001), but similar 1, 3, and 5-year survival (p = 0.63, p = 0.30, and p = 0.25), respectively). Conclusion: The development of hemothorax is associated with increased morbidity and decreased short-term survival. Hemothorax may present either within the first 48 h after surgery or in a delayed fashion, most commonly in the setting of anticoagulation.

Hemothorax following lung transplantation: incidence, risk factors, and effect on morbidity and mortality

BACKGROUND

Hemothorax after lung transplantation may result in increased post-operative morbidity and mortality. Risk factors for developing hemothorax and the outcomes of patients who develop hemothorax have not been well studied.

METHODS

A retrospective chart review was performed on all patients who underwent lung transplantation at a single center between March 2009 and July 2014. Comparison was made between patients with and without hemothorax post-transplant.

RESULTS

There were 132 lung transplantations performed during the study period. Hemothorax was a complication in 17 (12.9 %) patients, occurring an average of 9 days after transplant. No difference was found between the hemothorax and non-hemothorax groups with respect to age, preoperative anticoagulation, lung allocation score, prior thoracotomy, coagulation profile, use of cardiopulmonary bypass, ischemic time, or postoperative P/F ratio. There was a trend towards a higher incidence of hemothorax in patients with underlying sarcoidosis and re-transplantation (p = 0.13 and 0.17, respectively). Hemothorax developed early (<48 h post-operatively) in 5 patients and presented in a delayed manner (≥48 h post-operatively) in 12 patients. Delayed hemothorax occurred primarily in the setting of anticoagulation (10 out of 12 patients). The hemothorax group had decreased ventilator-free days (p = 0.006), increased ICU length of stay (p = 0.01) and increased hospital length of stay (p = 0.005). Hemothorax was also associated with reduced 90-day survival (p = 0.001), but similar 1, 3, and 5-year survival (p = 0.63, p = 0.30, and p = 0.25), respectively).

CONCLUSION

The development of hemothorax is associated with increased morbidity and decreased short-term survival. Hemothorax may present either within the first 48 h after surgery or in a delayed fashion, most commonly in the setting of anticoagulation.

Introducing routine HIV screening for patients on an internal medicine residency inpatient service: a quality improvement project

The US Centers for Disease Control and Prevention (CDC) recommend human immunodeficiency virus (HIV) screening for all persons aged 13 to 64 years who present to a health care provider. We sought to improve adherence to the CDC guidelines on the Internal Medicine Resident Hospital Service. We surveyed residents about the CDC guidelines, sent email reminders, provided education, and engaged them in friendly competition. Credit for guideline adherence was awarded if an offer of HIV screening was documented at admission, if a screening test was performed, or if a notation in the resident sign out sheet indicated why screening was not performed.

We examined HIV screening of a postintervention group of patients admitted between August 8, 2012, and June 30, 2013, and compared them to a preintervention group admitted between August 1, 2011, and June 30, 2012. Postintervention offers of HIV screening increased significantly (7.9% [44/559] vs 55.5% [300/541]; P<.001), as did documentation of residents' contemplation of screening (8.9% [50/559] vs 67.5% [365/541]; P<.001). A significantly higher proportion of HIV screening tests was ordered postintervention (7.7% [43/559] vs 44.4% [240/541]; P<.001). Monthly HIV screening documentation ranged from 0% (0/53) to 17% (9/53) preintervention, whereas it ranged from 30.6% (11/36) to 100% (62/62) postintervention.

HIV screening adherence can be improved through resident education, friendly competition, and system reminders. Barriers to achieving sustained adherence to the CDC guidelines include a heterogeneous patient population and provider discomfort with the subject.

Pulmonary artery size as a predictor of outcomes in idiopathic pulmonary fibrosis

IPF patients have heightened propensity for pulmonary hypertension, which portends a worse outcome. Presence of pulmonary hypertension may be reflected in an enlarged pulmonary artery. We investigated pulmonary artery size measured on high-resolution computed tomography (HRCT) as an outcome predictor in IPF.We retrospectively reviewed all IPF patients evaluated at a tertiary-care centre between 2008 and 2013. Pulmonary artery and ascending aorta diameters were measured from chest HRCT with pulmonary artery:ascending aorta diameter (PA:A) ratio calculations. Outcome analysis defined by either death or lung transplant based on pulmonary artery size and PA:A ratio over 60 months was performed. Independent effects of different variables on overall outcomes were evaluated using the Cox proportional hazards model.98 IPF patients with available HRCT scans had a mean pulmonary artery diameter and PA:A ratio of 32.8 mm and 0.94, respectively. Patients with a PA:A ratio >1 had higher risk of death or transplant compared with a PA:A ratio ≤1 (p<0.001). A PA:A ratio >1 was also an independent predictor of outcomes in unadjusted and adjusted outcomes analyses (hazard ratio 3.99, p<0.001 and hazard ratio 3.35, p=0.002, respectively).A PA:A ratio >1 is associated with worse outcomes in patients with IPF.

HRCT PA

A ratio measurement may assist in risk stratification and prognostication of IPF patients.

Pulmonary artery size as a predictor of pulmonary hypertension and outcomes in patients with chronic obstructive pulmonary disease

RATIONALE

The relationship between pulmonary artery size with underlying pulmonary hypertension and mortality remains to be determined in COPD. We sought to evaluate the relationships in a cohort of patients with advanced COPD.

METHODS

A retrospective study of advanced COPD patients evaluated between 1998 and 2012 was conducted at a tertiary care center. Patients with chest computed tomography images and right heart catheterizations formed the study cohort. The diameters of the pulmonary artery and ascending aorta were measured by independent observers and compared to pulmonary artery pressures. Intermediate-term mortality was evaluated for the 24-month period subsequent to the respective studies. Cox proportional hazards model was used to determine independent effects of variables on survival.

RESULTS

There were 65 subjects identified, of whom 38 (58%) had pulmonary hypertension. Patients with and without pulmonary hypertension had mean pulmonary artery diameters of 34.4 mm and 29.1 mm, respectively (p = 0.0003). The mean PA:A ratio for those with and without pulmonary hypertension was 1.05 and 0.87, respectively (p = 0.0003). The PA:A ratio was an independent predictor of mortality with a reduced survival in those with a PA:A >1 (p = 0.008).

CONCLUSIONS

The PA:A ratio is associated with underlying pulmonary hypertension in patients with COPD and is an independent predictor of mortality. This readily available measurement may be a valuable non-invasive screening tool for underlying pulmonary hypertension in COPD patients and appears to impart important independent prognostic information.