Basoudan N.,University of British Columbia |
Basoudan N.,Health Science University |
Shadgan B.,International Collaboration on Repair Discoveries |
Guenette J.A.,University of British Columbia |
And 3 more authors.
European Journal of Applied Physiology | Year: 2016
Purpose: To non-invasively examine the effect of acute hypoxia and inspiratory threshold loading (ITL) on inspiratory muscles [sternocleidomastoid (SCM), scalene (SA) and parasternal (PS)] oxygenation in healthy adults using near-infrared spectroscopy (NIRS). Methods: Twenty healthy adults (12 M/8 F) were randomly assigned to perform two ITL tests while breathing a normoxic or hypoxic (FIO2 = 15 %) gas mixture. NIRS devices were placed over the SCM, PS, SA, and a control muscle, tibialis anterior (TA), to monitor oxygenated (O2Hb), deoxygenated (HHb), total hemoglobin (tHb) and tissue saturation index (TSI). With the nose occluded, subjects breathed normally for 4 min through a mouthpiece that was connected to a weighted threshold loading device. ITL began by adding a 100-g weight to the ITL device. Then, every 2 min 50-g was added until task failure. Vital signs, ECG and ventilatory measures were monitored throughout the protocol. Result: Participants were 31 ± 12 year and had normal spirometry. At task failure, the maximum load and ventilatory parameters did not differ between the hypoxic and normoxic ITL. At hypoxic ITL task failure, SpO2 was significantly lower, and ∆HHb increased more so in SA, SCM and PS than normoxic values. SCM ∆TSI decreased more so during hypoxic compared to normoxic ITL. ∆tHb in the inspiratory muscles (SCM, PS and SA) increased significantly compared to the decrease in TA during both hypoxic and normoxic ITL. Conclusion: The SCM, an accessory inspiratory muscle was the most vulnerable to deoxygenation during incremental loading and this response was accentuated by acute hypoxia. © 2016, Springer-Verlag Berlin Heidelberg. Source
Linder A.,Center for Heart Lung Innovation |
Linder A.,Lund University |
Fjell C.,Center for Heart Lung Innovation |
Levin A.,University of British Columbia |
And 3 more authors.
American Journal of Respiratory and Critical Care Medicine | Year: 2014
Rationale: Long-term outcomes after acute kidney injury (AKI) are poorly described. Objectives: We hypothesized that one single episode of minimal (stage 1) AKI is associated with reduced long-term survival compared with no AKI after recovery from critical illness. Methods: A prospective cohort of 2,010 intensive care unit (ICU) patients admitted to the ICU between years 2000 and 2009 at a provincial tertiary care hospital. Development of AKI was determined according to the KDIGO classification and mortality up to 10 years after ICU admission was recorded. Measurements and Main Results: Of the 1,844 eligible patients, 18.4% had AKI stage 1, 12.1% had stage 2, 26.5% had stage 3, and 43.0%hadnoAKI.The 28-day, 1-year, 5-year, and 10-year survival rates were 67.1%, 51.8%, 44.1%, and 36.3% in patients with mild AKI, which was significantly worse compared with the critically ill patients with no AKI at any time (P< 0.01). The unadjusted 10-year mortality hazard ratio was 1.53 (95% confidence interval, 1.22.0) for 28-day survivors with stage 1 AKI compared with critically ill patients with no AKI. Adjusted 10-year mortality risk was 1.26 (1.01.6). After propensity matching stage 1 AKI with no AKI patients, mild AKI was still significantly associatedwith decreased 10-year survival (P=0.036). Conclusions: Patients with one episode of mild AKI have significantly lower long-term survival rates than critically ill patients with no AKI. Close medical follow-up of these patients may be warranted and mechanistic research is required to understand how AKI influences long-term events. © 2014 by the American Thoracic Society. Source
Fung G.,Center for Heart Lung Innovation |
Luo H.,Center for Heart Lung Innovation |
Qiu Y.,Center for Heart Lung Innovation |
Yang D.,Center for Heart Lung Innovation |
And 2 more authors.
Circulation Research | Year: 2016
Viral myocarditis remains a prominent infectious-inflammatory disease for patients throughout the lifespan. The condition presents several challenges including varied modes of clinical presentation, a range of timepoints when patients come to attention, a diversity of approaches to diagnosis, a spectrum of clinical courses, and unsettled perspectives on therapeutics in different patient settings and in the face of different viral pathogens. In this review, we examine current knowledge about viral heart disease and especially provide information on evolving understanding of mechanisms of disease and efforts by investigators to identify and evaluate potential therapeutic avenues for intervention. ©2016 American Heart Association, Inc. Source
Ryerson C.J.,St. Pauls Hospital |
Ryerson C.J.,Center for Heart Lung Innovation |
O'Connor D.,St. Pauls Hospital |
Dunne J.V.,St. Pauls Hospital |
And 6 more authors.
Chest | Year: 2015
BACKGROUND: Mortality risk prediction tools have been developed in idiopathic pulmonary fi brosis, however, it is unknown whether these models accurately estimate mortality in systemic sclerosis-associated interstitial lung disease (SSc-ILD). METHODS: Four baseline risk prediction models-the Composite Physiologic Index, the Interstitial Lung Disease-Gender, Age, Physiology Index, the du Bois index, and the modifi ed du Bois index-were calculated for patients recruited from a specialized SSc-ILD clinic. Each baseline model was assessed using logistic regression analysis with 1-year mortality as the outcome variable. Discrimination was quantifi ed using the area under the receiver operating characteristic curve. Calibration was assessed using the goodness-of-fi t test. Th e incremental prognostic ability of additional predictor variables was determined by adding prespecifi ed variables to each baseline model. RESULTS: The 156 patients with SSc-ILD completed 1,294 pulmonary function tests, 725 6-min walk tests, and 637 echocardiograms. Median survival was 15.0 years from the time of SSc-ILD diagnosis. All baseline models were signifi cant predictors of 1-year mortality in SSc-ILD. Th e modifi ed du Bois index had an area under the receiver operating characteristic curve of 0.84, compared with 0.77 to 0.81 in the other models. Calibration was acceptable for the modifi ed du Bois index, but was poor for the other models. All baseline models include FVC and 6-min walk distance was identified as an additional independent predictor of 1-year mortality. CONCLUSIONS: Th e modifi ed du Bois index has good discrimination and calibration for the prediction of 1-year mortality in SSc-ILD. FVC and 6-min walk distance are important independent predictors of 1-year mortality in SSc-ILD. © 2015 American College of Chest Physicians. Source
Suetrong B.,Center for Heart Lung Innovation |
Walley K.R.,Center for Heart Lung Innovation
Chest | Year: 2016
Increased blood lactate concentration (hyperlactatemia) and lactic acidosis (hyperlactatemia and serum pH < 7.35) are common in patients with severe sepsis or septic shock and are associated with significant morbidity and mortality. In some patients, most of the lactate that is produced in shock states is due to inadequate oxygen delivery resulting in tissue hypoxia and causing anaerobic glycolysis. However, lactate formation during sepsis is not entirely related to tissue hypoxia or reversible by increasing oxygen delivery. In this review, we initially outline the metabolism of lactate and etiology of lactic acidosis; we then address the pathophysiology of lactic acidosis in sepsis. We discuss the clinical implications of serum lactate measurement in diagnosis, monitoring, and prognostication in acute and intensive care settings. Finally, we explore treatment of lactic acidosis and its impact on clinical outcome. Copyright © 2016 American College of Chest Physicians. Published byElsevier Inc. All rights reserved. Source