ORCID Profile
0000-0003-2566-4308
Current Organisations
University of Toronto
,
University of Saskatchewan
,
Li Ka Shing Knowledge Institute
,
Unity Health Toronto
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Publisher: BMJ
Date: 03-2016
Publisher: Wiley
Date: 06-09-2022
DOI: 10.1111/TRF.17084
Abstract: Transfusion Requirements in Cardiac Surgery III (TRICS III), a multi‐center randomized controlled trial, demonstrated clinical non‐inferiority for restrictive versus liberal RBC transfusion for patients undergoing cardiac surgery. However, it is uncertain if transfusion strategy affects long‐term health‐related quality of life (HRQOL). In this planned sub‐study of Australian patients in TRICS III, we sought to determine the non‐inferiority of restrictive versus liberal transfusion strategy on long‐term HRQOL and to describe clinical outcomes 24 months postoperatively. The restrictive strategy involved transfusing RBCs when hemoglobin was .5 g/dl the transfusion triggers in the liberal group were: .5 g/L intraoperatively, .5 g/L in intensive care, or .5 g/dl on the ward. HRQOL assessments were performed using the 36‐item short form survey version 2 (SF‐36v2). Primary outcome was non‐inferiority of summary measures of SF‐36v2 at 12 months, (non‐inferiority margin: −0.25 effect size restrictive minus liberal scores). Secondary outcomes included non‐inferiority of HRQOL at 18 and 24 months. Six hundred seventeen Australian patients received allocated randomization HRQOL data were available for 208/311 in restrictive and 217/306 in liberal group. After multiple imputation, non‐inferiority of restrictive transfusion at 12 months was not demonstrated for HRQOL, and the estimates were directionally in favor of liberal transfusion. Non‐inferiority also could not be concluded at 18 and 24 months. Sensitivity analyses supported these results. There were no differences in quality‐adjusted life years or composite clinical outcomes up to 24 months after surgery. The non‐inferiority of a restrictive compared to a liberal transfusion strategy was not established for long‐term HRQOL in this dataset.
Publisher: Elsevier BV
Date: 2021
Publisher: Elsevier BV
Date: 04-2019
Publisher: Springer Science and Business Media LLC
Date: 24-12-2014
DOI: 10.1007/S12630-014-0302-Y
Abstract: Acute kidney injury (AKI) is a potentially serious complication of cardiac surgery. Anemia and red blood cell (RBC) transfusion have in idually been identified as potentially modifiable risk factors, but their interrelationship with AKI has not been clearly defined. The purpose of this study was to explore the interrelationship of preoperative anemia, intraoperative anemia, and RBC transfusion on the day of surgery with AKI in cardiac surgery. This historical cohort study included 16 hospitals, each contributing data on approximately 100 consecutive patients who underwent cardiac surgery with cardiopulmonary bypass. Acute kidney injury was defined as a > 50% increase in creatinine levels during the first postoperative week. Multivariable regression was used to identify the interrelationship between preoperative anemia (hemoglobin < 130 g·L(-1) in males and < 120 g·L(-1) in females), intraoperative anemia (hemoglobin < 80 g·L(-1) during cardiopulmonary bypass), RBC transfusion on the day of surgery, and their interaction terms, after adjusting for site and baseline AKI risk. Of the 1,444 patients included in the study, 541 (37%) had preoperative anemia, 501 (35%) developed intraoperative anemia, 619 (43%) received RBC transfusions, and 238 (16%) developed AKI. After risk-adjustment, an in idual with the combination of these three risk factors had a 2.6-fold (95% confidence interval 2.0 to 3.3) increase in the relative risk of AKI over an in idual with none of these risk factors. Preoperative anemia, intraoperative anemia, and RBC transfusion on the day of surgery are interrelated risk factors for AKI after cardiac surgery. Targeting these risk factors may reduce the burden of AKI.
Publisher: Elsevier BV
Date: 10-2014
DOI: 10.1053/J.JVCA.2013.10.005
Abstract: The primary objective of this study was to establish the relationship among tricuspid annular velocity (S'), tricuspid annular plane systolic excursion (TAPSE), and stroke volume (SV) in a cardiac surgical population with and without right ventricular (RV) dysfunction. The secondary objective was to assess the effect of ephedrine on these relationships in a population without RV dysfunction. Prospective, nonrandomized, unblinded study. Single tertiary-level, university-affiliated hospital. Twenty-seven patients undergoing elective coronary artery bypass grafting with no evidence of RV dysfunction (Group 1). Sixteen ventilated postcardiac surgical patients with suspected RV dysfunction (Group 2). Ten mg of intravenous ephedrine to Group 1 only. Using transthoracic echocardiography, S' and TAPSE were measured using color tissue Doppler applied at the RV base in a 4-chamber view. SV was calculated using thermodilution. Six patients in Group 1 and 6 patients in Group 2 were excluded because of poor imaging or ineligibility. Modest correlation was found between TAPSE and SV in Group 1 (R = 0.50, p<0.001). There was no correlation between TAPSE and SV in Group 2. There was no correlation between S' and SV in both groups. In Group 1, the relationship between TAPSE and S' was curvilinear (R = 0.74 pre-ephedrine, p<0.001 R = 0.64, p = 0.009 post-ephedrine). There was no relationship between TAPSE and S' in Group 2. Ephedrine increased S' and TAPSE. The TAPSE-S' relationship was not significantly altered. In the presence of RV dysfunction, TAPSE did not correlate with cardiac output. In the absence of RV dysfunction, the relationship between TAPSE and S' described a curvilinear relationship.
Publisher: Elsevier BV
Date: 03-2020
DOI: 10.1016/J.BJA.2019.11.025
Abstract: The Duke Activity Status Index (DASI) questionnaire might help incorporate self-reported functional capacity into preoperative risk assessment. Nonetheless, prognostically important thresholds in DASI scores remain unclear. We conducted a nested cohort analysis of the Measurement of Exercise Tolerance before Surgery (METS) study to characterise the association of preoperative DASI scores with postoperative death or complications. The analysis included 1546 participants (≥40 yr of age) at an elevated cardiac risk who had inpatient noncardiac surgery. The primary outcome was 30-day death or myocardial injury. The secondary outcomes were 30-day death or myocardial infarction, in-hospital moderate-to-severe complications, and 1 yr death or new disability. Multivariable logistic regression modelling was used to characterise the adjusted association of preoperative DASI scores with outcomes. The DASI score had non-linear associations with outcomes. Self-reported functional capacity better than a DASI score of 34 was associated with reduced odds of 30-day death or myocardial injury (odds ratio: 0.97 per 1 point increase above 34 95% confidence interval [CI]: 0.96-0.99) and 1 yr death or new disability (odds ratio: 0.96 per 1 point increase above 34 95% CI: 0.92-0.99). Self-reported functional capacity worse than a DASI score of 34 was associated with increased odds of 30-day death or myocardial infarction (odds ratio: 1.05 per 1 point decrease below 34 95% CI: 1.00-1.09), and moderate-to-severe complications (odds ratio: 1.03 per 1 point decrease below 34 95% CI: 1.01-1.05). A DASI score of 34 represents a threshold for identifying patients at risk for myocardial injury, myocardial infarction, moderate-to-severe complications, and new disability.
Publisher: Massachusetts Medical Society
Date: 27-09-2018
Publisher: Massachusetts Medical Society
Date: 16-07-2020
Publisher: Wiley
Date: 17-11-2022
DOI: 10.1111/DOM.14591
Abstract: To characterize the association between diabetes and transfusion and clinical outcomes in cardiac surgery, and to evaluate whether restrictive transfusion thresholds are harmful in these patients. The multinational, open‐label, randomized controlled TRICS‐III trial assessed a restrictive transfusion strategy (haemoglobin [Hb] transfusion threshold g/L) compared with a liberal strategy (Hb g/L for operating room or intensive care unit or g/L for ward) in patients undergoing cardiac surgery on cardiopulmonary bypass with a moderate‐to‐high risk of death (EuroSCORE ≥6). Diabetes status was collected preoperatively. The primary composite outcome was all‐cause death, stroke, myocardial infarction, and new‐onset renal failure requiring dialysis at 6 months. Secondary outcomes included components of the composite outcome at 6 months, and transfusion and clinical outcomes at 28 days. Of the 5092 patients analysed, 1396 (27.4%) had diabetes (restrictive, n = 679 liberal, n = 717). Patients with diabetes had more cardiovascular disease than patients without diabetes. Neither the presence of diabetes (OR [95% CI] 1.10 [0.93‐1.31]) nor the restrictive strategy increased the risk for the primary composite outcome (diabetes OR [95% CI] 1.04 [0.68‐1.59] vs. no diabetes OR 1.02 [0.85‐1.22] P interaction = .92). In patients with versus without diabetes, a restrictive transfusion strategy was more effective at reducing red blood cell transfusion (diabetes OR [95% CI] 0.28 [0.21‐0.36] no diabetes OR [95% CI] 0.40 [0.35‐0.47] P interaction = .04). The presence of diabetes did not modify the effect of a restrictive transfusion strategy on the primary composite outcome, but improved its efficacy on red cell transfusion. Restrictive transfusion triggers are safe and effective in patients with diabetes undergoing cardiac surgery.
Publisher: Elsevier BV
Date: 06-2018
Publisher: Springer Science and Business Media LLC
Date: 06-2000
Abstract: Partial liquid ventilation (PLV) improves gas exchange in animal studies of lung injury. Perfluorocarbons (PFCs) are heavy liquids and are therefore preferentially delivered to the most dependent areas of lung. We hypothesised that improved oxygenation during PLV might be the consequence of a redistribution of pulmonary blood flow away from poorly ventilated, dependent alveoli, leading to improved ventilation erfusion (V/Q) matching. This study investigated whether partially filling the lung with PFC would result in a redistribution of pulmonary blood flow. Prospective experimental study. Hospital research institute laboratory. Six anaesthetised pigs without lung injury. Animals were anaesthetised and ventilated (gas tidal volume 12 ml/kg, PEEP 5, FIO2 1.0, rate 16). Whilst the pigs were maintained in the supine position, regional pulmonary blood flow was measured during conventional gas ventilation and repeated during PLV. Flow to regions of lung was determined by injection of radioactive microspheres (Co(57), Sn(113), Sc(46)). Measurements were performed with ventilation held at end-expiratory pressure and, in two PLV animals only, repeated with ventilation held at peak inspiratory pressure. During conventional gas ventilation, blood flow followed a linear distribution with the highest flow to the most dependent lung. In the lung partially filled with PFC a ersion of blood flow away from the most dependent lung was seen (p = 0.007), resulting in a more uniform distribution of flow down the lung (p = 0.006). Linear regression analysis (r2 = 0.75) also confirmed a difference in distribution pattern. On applying an inspiratory hold to the liquid-containing lung, blood flow was redistributed back towards the dependent lung. Partially filling the lung with PFC results in a redistribution of pulmonary blood flow away from the dependent region of the lung. During PLV a different blood flow distribution may be seen between inspiration and expiration. The clinical significance of these findings has yet to be determined.
Publisher: Massachusetts Medical Society
Date: 03-06-2021
Publisher: Elsevier BV
Date: 2021
Publisher: Elsevier BV
Date: 08-2019
Start Date: 2019
End Date: 2022
Funder: Canadian Institutes of Health Research
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