Roy G Brower

Johns Hopkins University, Baltimore, Maryland, United States

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Publications (157)1153.12 Total impact

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    ABSTRACT: Introduction: The effect of exercise on cytokines may improve muscle strength. Neuromuscular electrical stimulation (NMES) is a muscle-preserving therapy that benefits patients unable to participate in active exercise. How NMES alters cytokines is unclear. The aim of this study was to study the effects of 1 NMES session on cytokines associated with protein metabolism during exercise. Methods: We evaluated the effects of NMES on IL-1, IL-6, IL-10 and TNF-α levels in peripheral blood. Participants received NMES to bilateral lower extremity muscles (quadriceps, tibialis anterior, gastrocnemius) for 30 min. Blood samples immediately pre- and post-NMES were drawn at 15-min intervals to 2-h follow-up, and the mean values of pre-NMES levels were compared to peak and trough post-NMES levels. For cytokines with significant changes, we conducted a repeated-measures linear regression analysis. We also measured post-NMES lactate and creatine kinase levels. Results: We enrolled nine eligible participants. There was a significant increase in peak IL-6 from the mean pre-NMES value [0·65 (0·89) to 1·04 (0·89) pg ml(-1) , P = 0·001] and a significant decrease in trough IL-1 [0·08 (0·07) to 0·02 (0·02) pg ml(-1) , P = 0·041] and TNF-α [2·42 (0·54) to 2·16 (0·59) pg ml(-1) , P = 0·021]. In repeated-measures regression analysis, we identified significantly higher mean IL-6 values throughout the full 120 min post-NMES period, and a significantly higher mean IL-1 value at 30 min post-NMES. There were no significant differences in peak IL-10, trough IL-6, lactate, or creatine kinase values. Conclusions: In nine healthy humans, 30 min of NMES was temporally associated with changes in cytokines similar to the effects of active exercise and may mediate NMES' observed effects on reducing muscle weakness.
    No preview · Article · Oct 2015 · Clinical Physiology and Functional Imaging
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    ABSTRACT: Abstract .Background: Recent recommendations for lung protective mechanical ventilation (MV) include a tidal volume (VT) target of 6 ml/kg predicted body weight (PBW). Different PBW equations might introduce important differences in tidal volumes delivered to research subjects and to patients. Methods: PBW equations use height, age, and gender as input variables. We compared NIH ARDS Network (ARDSNet), actuarial table (ACTUARIAL), and Stewart (STEWART) PBW equations used in clinical trials, across physiologic ranges for age and height. We used 3-D and 2-D surface analysis to compare these PBW equations. We then used age and height from actual clinical trial subjects to quantify PBW equation differences. Results: Significant potential differences exist between these PBW predictions. The ACTUARIAL and ARDSNet surfaces for women were the only surfaces that intersected and produced both positive and negative differences. Mathematical differences between PBW equations at limits of height and age exceeded 30% in women and 24% in men for ACTUARIAL versus ARDSNet, and about 25% for women and 15% for men for STEWART versus ARDSNet. The largest mathematical differences were present in older, shorter subjects, especially women. Actual differences for clinical trial subjects were as high as 15% for men and 24% for women. Conclusions: Significant differences between PBW equations for both men and women could be important sources of inter-study variation. Studies should adopt a standard PBW equation. We recommend using the NIH/NHLBI ARDS Network PBW equation because it is associated with the clinical trial that identified 6ml/kg PBW as an appropriate target. .
    No preview · Article · Mar 2015
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    ABSTRACT: Recent recommendations for lung protective mechanical ventilation (MV) include a tidal volume (VT) target of 6 ml/kg predicted body weight (PBW). Different PBW equations might introduce important differences in tidal volumes delivered to research subjects and to patients. PBW equations use height, age, and gender as input variables. We compared NIH ARDS Network (ARDSNet), actuarial table (ACTUARIAL), and Stewart (STEWART) PBW equations used in clinical trials, across physiologic ranges for age and height. We used 3-D and 2-D surface analysis to compare these PBW equations. We then used age and height from actual clinical trial subjects to quantify PBW equation differences. Significant potential differences exist between these PBW predictions. The ACTUARIAL and ARDSNet surfaces for women were the only surfaces that intersected and produced both positive and negative differences. Mathematical differences between PBW equations at limits of height and age exceeded 30% in women and 24% in men for ACTUARIAL versus ARDSNet, and about 25% for women and 15% for men for STEWART versus ARDSNet. The largest mathematical differences were present in older, shorter subjects, especially women. Actual differences for clinical trial subjects were as high as 15% for men and 24% for women. Significant differences between PBW equations for both men and women could be important sources of inter-study variation. Studies should adopt a standard PBW equation. We recommend using the NIH/NHLBI ARDS Network PBW equation because it is associated with the clinical trial that identified 6ml/kg PBW as an appropriate target.
    No preview · Article · Mar 2015 · Chest
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    ABSTRACT: Mechanical-ventilation strategies that use lower end-inspiratory (plateau) airway pressures, lower tidal volumes (VT), and higher positive end-expiratory pressures (PEEPs) can improve survival in patients with the acute respiratory distress syndrome (ARDS), but the relative importance of each of these components is uncertain. Because respiratory-system compliance (CRS) is strongly related to the volume of aerated remaining functional lung during disease (termed functional lung size), we hypothesized that driving pressure (ΔP=VT/CRS), in which VT is intrinsically normalized to functional lung size (instead of predicted lung size in healthy persons), would be an index more strongly associated with survival than VT or PEEP in patients who are not actively breathing. Using a statistical tool known as multilevel mediation analysis to analyze individual data from 3562 patients with ARDS enrolled in nine previously reported randomized trials, we examined ΔP as an independent variable associated with survival. In the mediation analysis, we estimated the isolated effects of changes in ΔP resulting from randomized ventilator settings while minimizing confounding due to the baseline severity of lung disease. Among ventilation variables, ΔP was most strongly associated with survival. A 1-SD increment in ΔP (approximately 7 cm of water) was associated with increased mortality (relative risk, 1.41; 95% confidence interval [CI], 1.31 to 1.51; P<0.001), even in patients receiving "protective" plateau pressures and VT (relative risk, 1.36; 95% CI, 1.17 to 1.58; P<0.001). Individual changes in VT or PEEP after randomization were not independently associated with survival; they were associated only if they were among the changes that led to reductions in ΔP (mediation effects of ΔP, P=0.004 and P=0.001, respectively). We found that ΔP was the ventilation variable that best stratified risk. Decreases in ΔP owing to changes in ventilator settings were strongly associated with increased survival. (Funded by Fundação de Amparo e Pesquisa do Estado de São Paulo and others.).
    Full-text · Article · Feb 2015 · New England Journal of Medicine
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    ABSTRACT: Mechanical ventilation is a cornerstone in the management of critically ill patients worldwide; however, less is known about the clinical management of mechanically ventilated patients in low and middle income countries where limitation of resources including equipment, staff and access to medical information may play an important role in defining patient-centred outcomes. We present the design of a prospective, longitudinal study of mechanically ventilated patients in Peru that aims to describe a large cohort of mechanically ventilated patients and identify practices that, if modified, could result in improved patient-centred outcomes and lower costs. Five Peruvian intensive care units (ICUs) and the Medical ICU at the Johns Hopkins Hospital were selected for this study. Eligible patients were those who underwent at least 24 h of invasive mechanical ventilation within the first 48 h of admission into the ICU. Information on ventilator settings, clinical management and treatment were collected daily for up to 28 days or until the patient was discharged from the unit. Vital status was assessed at 90 days post enrolment. A subset of participants who survived until hospital discharge were asked to participate in an ancillary study to assess vital status, and physical and mental health at 6, 12, 24 and 60 months after hospitalisation, Primary outcomes include 90-day mortality, time on mechanical ventilation, hospital and ICU lengths of stay, and prevalence of acute respiratory distress syndrome. In subsequent analyses, we aim to identify interventions and standardised care strategies that can be tailored to resource-limited settings and that result in improved patient-centred outcomes and lower costs. We obtained ethics approval from each of the four participating hospitals in Lima, Peru, and at the Johns Hopkins School of Medicine, Baltimore, USA. Results will be disseminated as several separate publications in different international journals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
    Preview · Article · Jan 2015 · BMJ Open

  • No preview · Article · Jan 2015
  • Claude Guérin · Taylor Thompson · Roy Brower

    No preview · Article · Dec 2014 · Intensive Care Medicine
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    ABSTRACT: Rationale: Reducing tidal volume decreases mortality in ARDS. However, the effect of the timing of low tidal volume ventilation is not well understood. Objectives: To evaluate the association of ICU mortality with initial tidal volume and with tidal volume change over time. Methods: Multivariable, time-varying Cox regression analysis of a multi-site, prospective study of 482 ARDS patients with 11,558 twice-daily tidal volume assessments (evaluated in ml/kg of Predicted Body Weight [PBW]) and daily assessment of other mortality predictors. Measurements and Main Results: An increase of 1 ml/kg PBW in initial tidal volume was associated with a 23% increase in ICU mortality risk (adjusted hazard ratio 1.23, 95% confidence interval [CI] 1.06--1.44, p=0.008). Moreover, a 1 ml/kg PBW increase in subsequent tidal volumes compared to the initial tidal volume was associated with a 15% increase in mortality risk (adjusted hazard ratio 1.15, 95% CI 1.02--1. 29, p=0.019). Compared to a prototypical patient receiving 8 days with a tidal volume of 6 ml/kg PBW, the absolute increase in ICU mortality (95% CI) of receiving 10 and 8 ml/kg PBW, respectively, across all 8 days was 7.2% (3.0 - 13.0%) and 2.7% (1.2-4.6%). In scenarios with variation in tidal volume over the 8-day period, mortality was higher when a larger volume was used earlier. Conclusions: Higher tidal volumes shortly after ARDS onset were associated with a greater risk of ICU mortality compared to subsequent tidal volumes. Timely recognition of ARDS and adherence to low tidal volume ventilation is important for reducing mortality. Clinicaltrials.gov NCT00300248.
    No preview · Article · Dec 2014 · American Journal of Respiratory and Critical Care Medicine
  • Neil R Aggarwal · Roy G Brower
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    ABSTRACT: It was recently suggested that targeting normoxemia (PaO2 85-110 mmHg) in ARDS patients might prevent neurocognitive dysfunction in survivors. However, targeting normoxemia may cause detrimental effects to the lungs from oxygen toxicity. Some have suggested that oxygen is not harmful to the lungs at FiO2s less than 0.6-0.7, but contrasting evidence in normal humans suggests that there can be untoward effects of moderate FiO2s. Furthermore, in experimental models of the acute respiratory distress syndrome, co-existing lung inflammation increases susceptibility to oxygen toxicity. Co-existing lung inflammation may lower the threshold for oxygen toxicity in patients with ARDS or in other acute illnesses in the lung. Moreover, physicians frequently prescribe higher FiO2s than are necessary to achieve their arterial oxygenation goal, further increasing the risk of oxygen toxicity. Targeting normoxemia in ARDS patients may prevent some long-term neurocognitive deficits in survivors, but it may increase lung inflammation and cause worse short-term clinical outcomes. We advocate for a clinical trial in ARDS patients to determine more appropriate goals for arterial oxygenation.
    No preview · Article · Oct 2014

  • No preview · Article · Oct 2014 · Chest
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    ABSTRACT: Background Donor to recipient lung size matching at lung transplantation (LTx) can be estimated by the predicted total lung capacity (pTLC)ratio (donor pTLC/recipient pTLC). We aimed to determine whether the pTLC-ratio is associated with the risk of primary graft dysfunction (PGD) after bilateral LTx (BLT). Methods We calculated the pTLC-ratio for 812 adult BLTs from the Lung Transplant Outcomes Group between 3/2002-12/2010. Patients were stratified by pTLC-ratio>1.0 ("oversized") and pTLC-ratio≤1.0 ("undersized"). PGD was defined as any ISHLT grade 3 PGD within 72 hours of reperfusion (PGD 3). We analyzed the association between risk factors and PGD using multivariable conditional logistic regression. As transplant diagnoses can influence the size matching decisions and also modulate the risk for PGD, we performed pre-specified analyses by assessing the impact of lung size mismatch within diagnostic categories. Results In univariate analyses oversizing was associated with a 39% lower odds of PGD3 (OR 0.61, 95% CI, p=0.003). In a multivariate model accounting for center effects and known PGD risks, oversizing remained independently associated with a decreased odds of PGD3 (OR 0.58, 95% CI 0.38-0.88, p=0.01). The risk adjusted point estimate was similar for the non-COPD diagnoses groups (OR 0.52, 95%CI 0.32-0.86, p=0.01); however there was no detected association within the COPD group (OR 0.72, 95% CI 0.29-1.78, p=0.5). Conclusion Oversized allografts are associated with a decreased risk of PGD3 after BLT; this effect appears most apparent in non-COPD patients.
    No preview · Article · Sep 2014 · The Journal of Heart and Lung Transplantation
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    ABSTRACT: Purpose: The purpose of the study is to compare neuromuscular electrical stimulation (NMES) vs sham on leg strength at hospital discharge in mechanically ventilated patients. Materials and methods: We conducted a randomized pilot study of NMES vs sham applied to 3 bilateral lower extremity muscle groups for 60 minutes daily in the intensive care unit (ICU). Between June 2008 and March 2013, we enrolled adults who were receiving mechanical ventilation within the first week of ICU stay and who could transfer independently from bed to chair before hospital admission. The primary outcome was lower extremity muscle strength at hospital discharge using Medical Research Council score (maximum, 30). Secondary outcomes at hospital discharge included walking distance and change in lower extremity strength from ICU awakening. Clinicaltrials.gov: NCT00709124. Results: We stopped enrollment early after 36 patients due to slow patient accrual and the end of research funding. For NMES vs sham, mean (SD) lower extremity strength was 28 (2) vs 27 (3), P = .072. Among secondary outcomes, NMES vs sham patients had a greater mean (SD) walking distance (514 [389] vs 251 [210] ft, P = .050) and increase in muscle strength (5.7 [5.1] vs 1.8 [2.7], P = .019). Conclusions: In this pilot randomized trial, NMES did not significantly improve leg strength at hospital discharge. Significant improvements in secondary outcomes require investigation in future research.
    No preview · Article · Sep 2014 · Journal of Critical Care
  • Michael Eberlein · Gregory A Schmidt · Roy G Brower
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    ABSTRACT: Chest wall strapping induces breathing at low lung volumes. Mild to moderate obesity can lead to similar changes in lung volumes, due to chest wall and abdominal restriction. Chest wall strapping is also conceptually similar to a mismatch between significantly oversized donor lungs transplanted into a recipient with a smaller chest cavity. Chest wall strapping increases lung elastic recoil, reduces pulmonary compliance, and substantially increases maximal expiratory flows. The interactions between elastic properties of the lung parenchyma and small airways are critical for pulmonary function. Chest wall strapping lowers residual volume and closing volume, likely from the interdependence between increased elastic recoil and airways leading to greater radial distending forces on small airways and small airway dilation. Chronic obstructive pulmonary disease (COPD) and chronic rejection of the transplanted lung, bronchiolitis obliterans syndrome (BOS), are primarily diseases of the small airways and are characterized by progressive obstruction and subsequent loss of small airways. In COPD, higher body mass index (BMI) (conceptually like being more tightly strapped) is associated with lower lung volumes, increased airway conductance, and with lower risk of progression to emphysema or death. Likewise, in lung transplantation, oversized donor lungs have been linked to higher expiratory airflows, lower risk of BOS, and improved survival. This paper reviews the physiology of chest wall strapping and explores how it could enhance the understanding or even the treatment of small airway diseases such as COPD and BOS.
    No preview · Article · Aug 2014
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    ABSTRACT: The use of extracorporeal membrane oxygenation (ECMO) for severe acute respiratory failure (ARF) in adults is growing rapidly given recent advances in technology, even though there is controversy regarding the evidence justifying its use. Since ECMO is a complex, high risk, and costly modality, at present it should be conducted in centers with sufficient experience, volume and expertise to ensure it is used safely. This position paper represents the consensus opinion of an international group of physicians and associated healthcare workers, who have expertise in therapeutic modalities used in the treatment of patients with severe ARF, with a focus on ECMO. The aim of this paper is to provide physicians, ECMO center directors and coordinators, hospital directors, health care organizations, regional, national and international policy makers a description of the optimal approach to organizing ECMO programs for ARF in adult patients. Importantly, this will help ensure that ECMO is delivered safely and proficiently, such that future observational and randomized clinical trials assessing this technique may be performed by experienced centers under homogeneous and optimal conditions. Given the need for further evidence, we encourage restraint in the widespread use of ECMO until we have a better appreciation for both the potential clinical applications and the optimal techniques for performing ECMO.
    No preview · Article · Jul 2014 · American Journal of Respiratory and Critical Care Medicine
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    ABSTRACT: Background: In the acute respiratory distress syndrome (ARDS), inflammation in the lungs and other organs can cause life-threatening organ failure. Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (statins) can modulate inflammatory responses. Previous observational studies suggested that statins improved clinical outcomes in patients with sepsis. We hypothesized that rosuvastatin therapy would improve clinical outcomes in critically ill patients with sepsis-associated ARDS. Methods: We conducted a multicenter trial in which patients with sepsis-associated ARDS were randomly assigned to receive either enteral rosuvastatin or placebo in a double-blind manner. The primary outcome was mortality before hospital discharge home or until study day 60 if the patient was still in a health care facility. Secondary outcomes included the number of ventilator-free days (days that patients were alive and breathing spontaneously) to day 28 and organ-failure-free days to day 14. Results: The study was stopped because of futility after 745 of an estimated 1000 patients had been enrolled. There was no significant difference between study groups in 60-day in-hospital mortality (28.5% with rosuvastatin and 24.9% with placebo, P=0.21) or in mean (±SD) ventilator-free days (15.1±10.8 with rosuvastatin and 15.1±11.0 with placebo, P=0.96). The groups were well matched with respect to demographic and key physiological variables. Rosuvastatin therapy, as compared with placebo, was associated with fewer days free of renal failure to day 14 (10.1±5.3 vs. 11.0±4.7, P=0.01) and fewer days free of hepatic failure to day 14 (10.8±5.0 vs. 11.8±4.3, P=0.003). Rosuvastatin was not associated with an increased incidence of serum creatine kinase levels that were more than 10 times the upper limit of the normal range. Conclusions: Rosuvastatin therapy did not improve clinical outcomes in patients with sepsis-associated ARDS and may have contributed to hepatic and renal organ dysfunction. (Funded by the National Heart, Lung, and Blood Institute and the Investigator-Sponsored Study Program of AstraZeneca; ClinicalTrials.gov number, NCT00979121.).
    Full-text · Article · Jun 2014 · New England Journal of Medicine
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    ABSTRACT: Between 10-57% of lung transplant (LTx) recipients develop primary graft dysfunction (PGD) within 72 hours of LTx. PGD is clinically and histologically analogous to the acute respiratory distress syndrome (ARDS). In patients at risk for, or with ARDS, lung protective ventilation strategies (low tidal volumes and positive end expiratory pressure) improve outcomes. There is, however, little information on mechanical ventilation strategies after LTx. The aim of this international survey was to describe the current practices of mechanical ventilation immediately after LTx. An electronic survey was sent to the medical and surgical directors of U.S. LTx programs (n=111) and to members of the Pulmonary Council of the International Society for Heart and Lung Transplantation (n=470). One hundred and forty-nine individuals from 18 countries responded to the questionnaire. The most common modes of ventilation were Pressure Assist/Control (37%) and Volume Assist/Control (35%). Tidal volumes were most often determined by recipient characteristics; donor characteristics were rarely considered (35%) and infrequently known by the team managing the ventilator (42%). When presented with a choice of ideal tidal volumes, a majority of respondents selected 6 ml/kg recipient predicted body weight (58%), fewer selected 10 ml/kg (21%), and none selected 15 ml/kg. A majority preferred limiting the fraction of inspired oxygen rather than positive end expiratory pressure (PEEP) (69% versus 31%, p = 0.006). The median minimum PEEP was 5 cm H2O and the median maximum PEEP was 11.5 cm H2O. The presence of PGD increased the perceived importance of monitoring plateau pressure to adjust tidal volumes. The median plateau pressure limit perceived as a threshold triggering reduction in tidal volumes was 30 cm H2O. Most respondents reported using lung-protective approaches to mechanical ventilation after lung transplantation. Low tidal volumes based on recipient characteristics were frequently chosen. Donor characteristics were often not considered and were frequently not known by the team managing mechanical ventilation after LTx.
    Preview · Article · Mar 2014 · Annals of the American Thoracic Society
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    ABSTRACT: Critically ill patients commonly experience poor sleep quality in the intensive care unit (ICU) because of various modifiable factors. To address this issue, an ICU-wide, multifaceted quality improvement (QI) project was undertaken to promote sleep in the Johns Hopkins Hospital Medical ICU (MICU). To supplement previously published results of this QI intervention, the present article describes the specific QI framework used to develop and implement this intervention, which consists of 4 steps: (a) summarizing the evidence to create a list of sleep-promoting interventions, (b) identifying and addressing local barriers to implementation, (c) selecting performance measures to assess intervention adherence and patient outcomes, and (d) ensuring that all patients receive the interventions through staff engagement and education and regular project evaluation. Measures of performance included daily completion rates of daytime and nighttime sleep improvement checklists and completion rates of individual interventions. Although long-term adherence and sustainability pose ongoing challenges, this model provides a foundation for future ICU sleep promotion initiatives.
    No preview · Article · Nov 2013 · American Journal of Medical Quality
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    ABSTRACT: Rationale: The association between a high predicted total lung capacity (pTLC)-ratio (=pTLCdonor / pTLCrecipient), suggestive of an oversized allograft, with improved survival after lung transplantation (LTx) remains controversial. Objective: To characterize the donor-recipient lung size matching based on the pTLC-ratio and to investigate the relationship of the pTLC-ratio with post-LTx survival. Methods: All subjects in the SRTR transplant registry, who underwent first-time LTx in the lung allocation score based system between May 4th 2005 and March 31st 2012 were studied, and the pTLC-ratio was calculated based on gender, height and age. Risk of death after LTx was analyzed using Cox proportional hazards models. Measurements and Main Results: The pTLC-ratio was available for 10,289 of the 10,318 study subjects (99.7%). The mean pTLC-ratio was 1.015 ± 0.175 (interquartile range [IQR] 0.918-1.119). Univariate analysis showed that the pTLC-ratio was strongly associated with death in the first LTx year (p < 0.0001). With the pTLC-ratio entered as a spline there was a non-linear association with declining risk of death with higher pTLC-ratio from 0.5 to about 1.3, where an inflection occurred with rising risk at higher values. Accounting for the pTLC-ratio, recipient and donor gender were not independently associated with death after LTx. The comparison of pTLC-ratio from 1.119 to 0.918 (the IQR) was associated with similar point estimates of reduced risk of death at one year across univariate (HR 0.78) and comprehensive risk adjusted multivariate models (HR 0.86). Conclusion: The pTLC-ratio is an independent predictor of death in the first year after LTx and explains the association of gender with survival after LTx. Incorporating the pTLC-ratio in the lung allocation mechanism could improve outcomes after LTx.
    No preview · Article · Aug 2013 · Annals of the American Thoracic Society
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    Roy G Brower

    Preview · Article · Aug 2013 · Intensive Care Medicine
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    ABSTRACT: A higher predicted total lung capacity (pTLC)-ratio (=pTLC donor/pTLC recipient), suggestive of oversized allografts, is associated with improved survival after lung transplantation. It is unknown whether the pTLC-ratio has a different association with survival in bilateral (BLT) versus single lung transplantation (SLT). The pTLC-ratio was calculated for all adult patients in the United Network of Organ Sharing lung transplant (LTx) registry who underwent first-time LTx in the post lung allocation score era, between May 2005 and April 2010. The LTx recipients were stratified according to procedure (BLT vs SLT). Risk of death at 1 year after LTx was analyzed using Kaplan-Meier survival and Cox proportional hazards models. In the 4,520 BLT patients, each 0.1 increase in pTLC-ratio conferred a 7% decrease in the hazard for death at 1 year (p < 0.001) in univariate analysis. This association remained significant after controlling for diagnosis, comorbidities, acuity, donor, and transplant factors (hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.88 to 0.98, p = 0.01). Additional adjustment by a propensity score to account for biases to oversizing showed similar results (HR 0.94, 95% CI 0.90 to 0.99, p = 0.018). In the 2,477 SLT patients, each 0.1 increase in pTLC-ratio conveyed a 6% decrease in the hazard for death at 1 year (p = 0.002) in univariate analysis, which did not persist in the multivariate model (HR 1.00, p = 0.8). A higher pTLC-ratio, suggestive of an oversized allograft, is associated with improved survival after lung transplantation. This association is primarily evident in BLT patients.
    No preview · Article · Jun 2013 · The Annals of thoracic surgery

Publication Stats

8k Citations
1,153.12 Total Impact Points

Institutions

  • 1988-2015
    • Johns Hopkins University
      • • Department of Medicine
      • • Division of Pulmonary and Critical Care Medicine
      • • Department of Physical Medicine and Rehabilitation
      Baltimore, Maryland, United States
  • 1985-2011
    • Johns Hopkins Medicine
      • • Department of Medicine
      • • Division of Pulmonary and Critical Care Medicine
      Baltimore, Maryland, United States
  • 2007
    • University of Toronto
      Toronto, Ontario, Canada
  • 2004
    • University of Pennsylvania
      Philadelphia, Pennsylvania, United States
  • 2003-2004
    • Duke University
      Durham, North Carolina, United States