University of Manitoba Scholarship
Permanent URI for this collection
Overview
This collection contains open access research publications authored or co-authored by University of Manitoba researchers. Content within this collection includes pre and post-print versions of articles and book chapters, conference proceedings and technical reports. MSpace is where faculty and students can deposit their research output to meet the open access requirements of grant funding agencies and other related mandates. Deposit is subject to copyright compliance, distribution license and other license restrictions that may be imposed on the work.
Before You Submit
All submissions are subject to content and MSpace policies. Submitters are required to acknowledge compliance with these and copyright and publication licences to successfully deposit. Go to My MSpace to begin the submission process and, when prompted, choose the University of Manitoba Scholarship collection. Unfinished or rejected submissions can be restarted by accessing My MSpace.
Browse
Recent Submissions
- ItemOpen AccessComputed tomography perfusion assessment of poor neurological outcome in comatose cardiac arrest patients (CANCCAP): a prospective study(BMC, 2025-05-23) Shankar, Jai; Alcock, Susan; Wiens, Evan; Ayroso, Marco; Park, JaeYeon; Singh, Navjit; Blackwood, Benjamin ; Trivedi, Reva; Marin, Roman; Sinha, Namita; Trivedi, Anurag; Kirkpatrick, Iain; Essig, Marco; Schaffer, StephenAbstract Background Computed tomography perfusion (CTP) of the brain, are increasingly being employed for the assessment of critically ill patients admitted to intensive care units (ICU), including comatose cardiac arrest patients (CCAP). The purpose of our study was to validate the use of CTP in predicting in-hospital mortality in CCAPs. Method This prospective cohort study enrolled newly admitted adult CCAP, with an out of hospital cardiac arrest (OHCA) and were scheduled for admission to the ICU for further management. Just before ICU admission, CCAP underwent a routine CT scan of the head and CTP of whole head. The treating physicians remained blinded to the CTP results and all patients received standard management. The CTP maps were evaluated to determine a binary outcome of non-survivable brain injury (NSBI), by two independent neuroradiologists, blinded to each other’s assessment and to the clinical history of the patients. Results A total of 91 patients were enrolled and 90 (Male-78; mean age-62 years) were included in the final analysis. One patient declined consent. Of these, 42 individuals (47%) had in-hospital mortality. Patients with in-hospital mortality were older; had higher levels of creatinine, blood urea nitrogen, blood CO2 and lower pH, carbonate, and heart rate. In multivariate analysis, PCI was independently associated with reduction in-hospital mortality. CTP demonstrated exceptionally high specificity (100%; 95% CI 92–100%) and positive predictive value (100%; 95%CI 6.3–100%) for the prediction of NSBI. For CTP, Bennet’s S-score showed excellent agreement between the two readers (s = 0.82–0.95). Conclusion CTP was safe and demonstrated very high specificity and positive predictive value and may be used as an additional diagnostic tool for identifying patients at high risk of in-hospital mortality.
- ItemOpen AccessErroneous calibration of esophageal pressure in case of airway closure(BMC, 2025-05-02) Docci, Mattia; Beloncle, Francois; Lesimple, Arnaud; Piraino, Thomas; Raimondi Cominesi, Davide; Restivo, Andrea; Sousa, Mayson L. A.; Rezoagli, Emanuele; Mercat, Alain; Richard, Jean-Christophe; Brochard, LaurentAbstract Airway closure results in a lack of communication between proximal and distal airways unless the airway pressure (Paw) overcomes the airway opening pressure (AOP). This has been described in patients undergoing mechanical ventilation with acute respiratory distress syndrome, obesity, hydrostatic pulmonary edema and during cardiopulmonary resuscitation. In these categories of patients, esophageal pressure (Pes) can guide the personalization of mechanical ventilation and calibration of the esophageal balloon is necessary to obtain reliable Pes measurements. The impact of airway closure has never been envisaged. This study investigated the impact of airway closure on the calibration of the esophageal balloon by the ∆Paw/∆Pes following a positive pressure occlusion test during passive mechanical ventilation. The calibration test was performed in twelve human cadavers with airway closure at end-expiration at different levels of positive end-expiratory pressure (PEEP) and at end-inspiration. The ∆Paw/∆Pes measured at end-expiration and at end-inspiration were significantly different when total PEEP was lower than AOP (estimated means 0.42 [0.40; 0.44] vs. 0.95 [0.92; 0.97], P < 0.001), while this difference was not observed when total PEEP was higher than AOP (estimated means 0.99 [0.92; 1.05] vs. 0.99 [0.92; 1.06], P = 0.854). These results were corroborated by observations during esophageal balloon calibration in two patients requiring Pes monitoring for clinical management. In case of airway closure, compression of the chest is not fully transmitted to the airways. This can lead to a conspicuous underestimation of the ∆Paw/∆Pes and poor reliability of this monitoring technique when the test takes place below AOP. Our results favor a positive pressure occlusion test performed during an end-inspiratory occlusion as the new standard of operative procedures for positioning and calibrating the esophageal balloon.
- ItemOpen AccessDiagnosis of in-hospital mortality using admission CT perfusion in severe traumatic brain injury patients (ACT-TBI study)(BMC, 2025-05-01) Shankar, Jai; Alcock, Susan; Leeies, Murdoch; Ayroso, Marco; Unrau, Sarah; Park, JaeYeon; Blackwood, Benjamin ; Trivedi, Reva; Marin, Roman; Raja, Muhammed; Sinha, Namita; Trivedi, Anurag; Essig, Marco; Martin, Douglas; Grierson, Robert; Zeiler, Frederick A.Abstract Background Severe traumatic brain injury (TBI) stands as the leading cause of post-injury hospitalization, disability, and mortality globally. Imaging serves as a cornerstone in the assessment of patients with severe TBI and CT Perfusion (CTP) has emerged as an early prognostic tool. Our study aims to validate CTP features of non-survivable brain injury, upon hospital admission to characterize in-hospital mortality, through a well-powered prospective cohort study. Methods In a prospective cohort study, adult patients with severe TBI were recruited to undergo whole head CTP at the time of their first imaging. Interpretation of the CTP images were conducted by two independent neuroradiologists (JS and ME), blinded to clinical results and each other’s assessment. Non-survivable brain injury was defined as a matched decrease of cerebral blood flow (CBF) and cerebral blood volume (CBV) in the brainstem. The results of CTP were not disclosed to the clinical team providing patient care, and the patients received standard institutional management. The primary outcome was a binary outcome of in-hospital mortality. The primary validity analysis involved calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for features of non-survivable brain injury on admission CTP compared to in-hospital mortality, along with 95% confidence intervals. Results Out of the 201 patients initially enrolled in the study, 195 patients (mean age 42.9 years; Male- 160, 82%) were included in the final analysis. Among the participants, a total of 55 patients (28.2%) died during their hospital stay. The odds ratio (OR) was highest for the presence of intracranial hemorrhage (ICH) (OR-20.25; 95% CI- 7.08–71.80, p < 0.001) and gun shot wound (GSW) (OR-22.67; 95% CI- 3.66–257.5, p = 0.003), which were independently associated with in-hospital mortality. With every decade of age, there was 1.77 times of (95% CI- 1.37–2.36, p < 0.001) higher odds of in-hospital mortality. Of the 55 patients with in-hospital mortality, 17 (31%) met the criteria of non-survival brain injury on the CTP at the time of hospital admission. Both CTP and CT-angiogram (CTA)A had 100% specificity and PPV. The highest sensitivity of 33% and NPV of 80% was seen with non-survivable criteria of CTP. As a result, this variable exhibited the highest accuracy of 82% with an area under the curve (AUC) of 0.67. The inter-rater reliability for CTP ranged from poor (kappa = 0.07) to fair (kappa = 0.44), indicating variability in agreement between raters. In contrast, the inter-rater reliability for CTA scales ranged from fair (kappa = 0.39) to substantial (kappa = 0.79), suggesting more consistent agreement among raters. CTP was found to be safe as no patients experience any complications associated with CTP. Conclusion CTP features of non-survivable brain injury showed very high specificity and positive predictive value for diagnosing in-hospital mortality in patients with severe TBI.
- ItemOpen AccessFunctional work disability from the perspectives of persons with systemic lupus erythematosus: a qualitative thematic analysis(BMC, 2025-05-26) Nowrouzi-Kia, Behdin; Howe, Aaron S.; Li, Anson; Tan, Jeremy; Saade-Cleves, Natalia; Jules, Kevon; Sadek, Malak; Bani-Fatemi, Ali; Avina-Zubieta, Antonio; Fox, Mary T.; Shaw, William; Haaland, Derek; Pope, Janet; Fortin, Paul R.; Bingham, Kathleen S.; Peschken, Christine; Reynolds, Jennifer; Ivory, Catherine; Gladman, Dafna D.; Urowitz, Murray B.; Sanchez-Guerrero, Jorge; Lim, Lily S. H.; Keeling, Stephanie; Katz, Patti; Kavkan, Mahta; Bonilla, Dennisse; Nielsen, Wils; Touma, ZahiAbstract Background Systemic lupus erythematosus (SLE) disease symptoms that can significantly restrict work ability and work participation resulting in reduced mental well-being. This study investigates the significant impact of work participation and disability on the mental wellbeing, health-related quality of life, and disease-related outcomes in individuals with SLE. Methods With the objective of creating an SLE-related functional profile rooted in work disability (WD) prevention, 46 SLE patients were purposively recruited from Canadian medical centres. Through semi-structured interviews guided by a WD prevention framework, factors associated with WD and lived experiences of SLE-related WD were qualitatively explored. Braun and Clarke’s six-stage inductive thematic analysis was used to organize the data. Results Most participants experienced some form of work disability across their employment history related to their clinical manifestations of SLE, including hospitalizations, physical limitations, fatigue, and neurocognitive symptoms (e.g. brain fog). Thematic analysis revealed three key themes: (a) the influence of illness experience on work, (b) the stigmatization of illness disclosure, and (c) the availability of workplace resources/accommodations. Participants emphasized the desirability of work with reduced physical and mental demands, increased personal control, and workplace flexibility to prevent WD. Conclusion The study underscores the need for a collaborative, multi-component, and multidisciplinary intervention targeting psychosocial and workplace factors to establish a goal-oriented preventative framework, potentially improving WD outcomes in SLE individuals.
- ItemOpen AccessContextual factors related to aging determine force-based manipulation dosage: a prospective cross-sectional study(BMC, 2025-05-21) Maiers, Michele J.; Sundin, Alexander R.; Oster, Ryan J.; Kreul, Steven; Malone, Quinn; Passmore, Steven R.Abstract Background Contextual factors influence clinicians’ delivery of force-based manipulation (FBM), like spinal manipulative therapy (SMT). It is particularly important to discern how contextual factors interact with therapeutic forces delivered to an older adult population, to minimize risk and identify ideal dosage. This study aimed to determine whether contextual factors pertaining to aging result in the modulation of kinetic and kinematic parameters used by experienced clinicians when delivering SMT. Methods Participants were randomly presented with a series of 12 AI-generated patient vignettes, featuring both visual and auditory content and representing varying age-related contextual factors. Factors included chronological (35-, 65- and 85-year-old), pathological (“healthy” vs degenerative spine), and felt (perceived as “young” vs. “old”) age. Participants delivered SMT to a human analogue manikin based on each vignette, presented six times in randomized order. Kinetic and kinematic parameters were collected and analyzed for differences between “young” and “old” contextual factors of age, using a 3-way repeated measures ANOVA model. Results Sixteen licensed chiropractors (8 female, 8 male) participated, with an average age of 45.4 (SD = 9.7, range 34–64) years and 18.3 (SD = 10.8, range 5–39) years of experience. A main effect in peak force was found for both chronological (F(2,30) = 26.18; p <.001, ηp2 = 0.636) and pathological age (F(1,15) = 11.58; p =.004, ηp2 = 0.436), following a stepwise progression of decreased force with increased age and with pathology. No statistically significant differences were found in peak force based on felt age, or in time to peak force for any factor. A main effect was found for chronological age with peak acceleration (F(2,20) = 9.50; p <.001, ηp2 = 0.487) and peak velocity (F(2,20) = 7.20; p =.004, ηp2 = 0.419), but not for pathological or felt age. There was a significant difference in time to peak velocity for felt age (F(1,10) = 12.23; p =.006, ηp2 = 0.550), with a shorter time to peak velocity in response to vignettes with older felt age. Conclusion Contextual factors of aging modulated certain kinetic and kinematic characteristics when delivering SMT. This provides evidence that practitioners differentially discern aspects of aging to inform how they deliver FBM dosage. Future research is needed to identify ideal kinetic and kinematic characteristics based on considerations of aging.