Foothills Medical Centre

Obstructive sleep apnea is an independent risk factor for stroke, potentially due to intermittent hypoxia (IH)-induced impairment of cerebral autoregulation. Human cerebral autoregulation during sleep is poorly characterized, and whether IH exposure during sleep alters cerebral autoregulation during sleep is unknown. In a secondary, exploratory analysis of previously collected cerebral blood flow (transcranial Doppler ultrasound measurement of peak blood velocity through the middle cerebral artery; [Formula: see text]), mean arterial pressure (MAP; finger photoplethysmography), and end-tidal partial pressure of CO2 ([Formula: see text]) data, dynamic cerebral autoregulation (dCA) was quantified using transfer function analysis gain, phase, and coherence in healthy males (n = 10; age: 26 ± 6 yr; body mass index: 24.5 ± 1.7 kg/m2; MAP: 87.5 ± 8.0 mmHg) during wakefulness and during nonrapid eye movement (NREM) sleep in normoxia or accompanied by IH. Compared with wakefulness, [Formula: see text] variability was lower during both sleep in normoxia and sleep accompanied by IH in the very low frequency (0.02-0.07 Hz) and low frequency (LF: 0.07-0.2 Hz) ranges (both comparisons, P ≤ 0.02) with MAP variability being lower in the LF range (P = 0.045); gain, phase, and coherence were similar between wakefulness and sleep (all comparisons, P ≥ 0.062). dCA measures during normoxic and IH-sleep were similar (all comparisons, P ≥ 0.09). Moreover, dCA gain and phase, and multiple and partial coherences during IH-sleep were not different between acute (<1 h) and prolonged (∼2 h) exposure (all comparisons, P ≥ 0.055) even though [Formula: see text] was lower following prolonged IH exposure (P = 0.002). These findings indicate dCA is effective during stage 2/3 NREM sleep and is not impacted by ∼2 h of sleep accompanied by IH.NEW & NOTEWORTHY This study found that dynamic cerebral autoregulation (dCA) is not different between wakefulness and stages 2/3 nonrapid eye movement (NREM) sleep in young healthy males and that ∼2 h of intermittent hypoxia exposure during sleep mimicking that experienced by patients with moderate-to-severe obstructive sleep apnea does not alter NREM stage 2/3 sleep dCA. This maintained dCA during sleep may result from the reduced cerebral blood flow and blood pressure variability observed during sleep.

Adults with spinal cord injury/ dysfunction (SCI/D) commonly take multiple medications for a variety of secondary conditions, and have described challenges with medication self-management. To help support medication self-management, a web-based toolkit, MedManageSCI, was co-designed by our team of researchers and adults with SCI/D, caregivers, and healthcare providers (www.medmanagesci.ca). Together, we co-developed the content areas to include in MedManageSCI, along with the design and brand considerations, to create an initial prototype of the toolkit. To finalize the prototype prior to implementation, the primary objective of this qualitative study was to further refine MedManageSCI by examining the clarity, comprehensiveness, relevance, and delivery of the toolkit modules. Cognitive interviews were conducted virtually between July 2024 and September 2024 with adults with SCI/D (N = 16). A concurrent verbal probing approach using scripted and spontaneous probes was followed. Data were coded using a pre-established coding matrix that aligned with the scripted probes. Participants provided 193 specific modifications to improve the clarity, comprehensiveness, relevance, or delivery of the MedManageSCI toolkit, which were categorized as: Comprehension, Design, and Web-based Delivery. The Comprehension category contained three subcategories: Written Refinements, Ensuring Accessibility, and Revamping Resources. The Design category contained three subcategories: Formatting Content, Streamlining Function, and Enhancing Visuals. Participants perceived the website as an ideal way to deliver the toolkit, noting several benefits of a web-based delivery in comparison to a paper-based toolkit. Overall, participants found the modules to be comprehensive and highly relevant. Further, we discuss the application of cognitive interviews for further refining the MedManageSCI prototype, recommendations to improve the comprehensibility, and the advantages of a web-based toolkit for the SCI/D population. Involving individuals with SCI/D in the development and refinement of self-management materials will help ensure that the content and resources are tailored and appropriate; thereby elevating its likelihood of uptake and dissemination during implementation.

Many national medical governing bodies encourage physicians to engage in continuing professional development (CPD) activities to cultivate their knowledge and skills to ensure their clinical practice reflects the current standards and evidence base. However, physicians often encounter various barriers that hinder their participation in CPD programs, such as time constraints, a lack of centralized coordination, and limited opportunities for self-assessment. The literature has highlighted the strength of using question-based learning interventions to augment physician learning and further enable change in practice. CPD By the Minute (CPD-Min) is a smartphone-enabled web-based app that was developed to address self-assessment gaps and barriers to engagement in CPD activities. This study aimed to assess the app using four objectives: (1) engagement and use of the app throughout the study, (2) effectiveness of this tool as a CPD activity, (3) relevance of the disseminated information to physicians' practice, and (4) acceptability to physicians of this novel tool as an educational initiative. The CPD-Min app disseminated 2 multiple-choice questions (1-min each) each week with feedback and references. Participants included licensed staff physicians, fellows, and residents across Canada. A concurrent multimethods study was conducted, consisting of preintervention and postintervention surveys, semistructured interviews, and app analytics. Guided by the Reach, Effectiveness, Adoption, Implementation, and Maintenance framework, the qualitative data were analyzed deductively and inductively. Of the 105 Canadian anesthesiologists participating in the study, 89 (84.8%) were staff physicians, 12 (11.4%) were fellows, and 4 (3.8%) were residents. Participants completed 110 questions each over the course of 52 weeks, with an average completion rate of 75% (SD 33%). In total, 40.9% (43/105) of participants answered >90% of the questions, including 15.2% (16/105) who completed all questions. Moreover, 69% (52/75) of participants reported the app to be an effective and valuable resource for their practice and to enhance continuous learning. Most participants (63/75, 84%) who completed the postsurveys reported that they would likely continue using the app as a CPD tool. These findings were further supported by the interview data. Three key themes were identified: the practical design of the novel educational app facilitates its adoption by clinicians, the app was perceived as a useful knowledge tool for continuous learning, and the app's low-stakes testing environment cultivated independent learning attitudes. The findings suggest the potential of the app to improve longitudinal assessments that promote lifelong learning among clinicians. The positive feedback and increased acceptance of the app supports it as an innovative tool for knowledge retention and CPD. Future research efforts should prioritize evaluating the app's long-term sustainability and its impact on physicians' practice, as well as exploring alternative approaches (such as artificial intelligence-based tools) for generating questions.

In this Continuing Professional Development module, we review the literature on postdural puncture headache (PDPH) in obstetrics. The pathophysiology, risk factors, diagnosis, and outcomes are discussed. We explore the evidence for prevention and treatment options of PDPH in obstetric patients and the importance of the anesthesiologist's role in caring for these patients. A PDPH is any headache that develops after a dural puncture and is not better accounted for by another diagnosis. Risk factors for PDPH include young age and female sex, which, along with the high rate of neuraxial anesthesia use in the obstetric population, predispose these patients to this complication. A spinal anesthesia technique using a small-gauge pencil-point needle with an experienced operator decreases the risk of PDPH. Individuals with PDPH have an increased risk of major neurologic complications, such as subdural hematoma, cerebral venous sinus thrombosis, and bacterial meningitis. No pharmacological modalities have shown a benefit in preventing or treating PDPH. Epidural blood patch remains the most effective treatment for PDPH and should not be delayed in obstetric patients with severe symptoms. Postpartum individuals cope with recovering from birth in addition to the demands of caring for a newborn. Often, the addition of a PDPH is incapacitating. Epidural blood patch should not be delayed in patients with early and severe symptoms. All individuals who experience PDPH should be assessed, receive appropriate treatment, and be reviewed by a member of the anesthesia team until symptoms have resolved, with appropriate follow-up instructions before discharge.

Study ObjectivesThere is a higher risk of cardiovascular disease (CVD) in patients with obstructive sleep apnea (OSA) and innate immunity is a potential pathophysiologic pathway. The objective of this study was to determine whether nocturnal hypoxemia is associated with circulating markers of innate immunity in OSA.MethodsThis was a cross-sectional study of an observational cohort from the multicentre, clinic-based, Canadian Sleep and Circadian Network. Oxygen desaturation index 4% (ODI4%) was used to diagnose and determine the severity of OSA. The percentage of time spent below SpO2 <90% (T90) and minimum SpO2 we considered as other measures of nocturnal hypoxemia. Multiple linear regressions were used to assess associations between total white blood cell (WBC) and subsets and ODI and hypoxemia indices.ResultsA total of 1296 patients were included in the analysis. There was a positive association between ODI4% and lymphocyte count, adjusting for confounders. For every 1-SD increase in ODI4%, lymphocyte counts increased by 0.08 × 109 L (95% CI 0.01 to 0.15) SD. Patients with severe OSA (ODI4% ≥ 30 events/hour) had significantly higher total WBC and lymphocyte count than non-OSA cohort, in the adjusted model, p-value <.02, for both. There was a positive association between T90 and total WBC, neutrophil, lymphocyte, and monocyte count, adjusting for confounders. Minimum SpO2 was independently associated with total WBC, neutrophil, and monocyte counts.ConclusionsIn this pan-Canadian clinic-based cohort of individuals with suspected OSA, nocturnal hypoxemia indices were associated with an increase in total WBC and subset counts.

The threat of tariffs from the current US administration is top of mind for most Canadians of late. Tariffs have the potential for damaging the Canadian economy, putting people out of work, and sowing the seeds for discontent, substance use, and addiction. One of the reasons cited for the imposition of tariffs was that Canada lacks border security, supposedly allowing vast quantities of fentanyl to enter the United States, despite a lack of evidence to support this claim.1 It also runs contrary to most effective approaches to deal with illicit drugs. In an underacknowledged landmark report,2 the RAND Corporation found that addressing the demand for cocaine by treating heavy users of cocaine was vastly more cost-effective than measures to curtail supply. In comparing the relative cost benefits of source-country control (coca leaf eradication and seizures in source countries), interdiction (cocaine and asset seizures by US Customs, US Coast Guard, US Army, and Immigration and Naturalization Services), domestic enforcement (cocaine seizures, asset seizures, and arrests of dealers and their agents by federal, state, and local law enforcement, as well as imprisonment of convicted drug dealers and their agents), and treatment of heavy users (outpatient and bed-based treatment programs), for every 1 dollar spent, source-country control returned 15 cents on the dollar, interdiction returned 32 cents on the dollar, and domestic enforcement returned 52 cents on the dollar. Comparatively, the treatment of heavy users returned $7.46 on every dollar spent. The report recommended diverting spending away from attempting to curtail supply or enforcement, as has been the predominant focus of the War on Drugs, to the treatment of heavy cocaine users. Previously, up to 70% of funding in Canada for addressing illicit substance use was allocated to enforcement strategies, resulting in increased incarceration rates,3 but over the years Canada has developed a more balanced approach where of the $513.4 million spent annually on the anti-drug strategy, 40% goes to enforcement, 37% to treatment, and 23% to prevention.4 The prior focus on enforcement also had the unintended consequence of shifting the drug supply from naturally sourced substances, like cocaine and heroin, to chemically created substances that are highly concentrated as they are less likely to be stopped by source-country control and interdiction as they can be mailed or domestically made from chemical precursors.5,6 As Fischer et al6 note in their important commentary in this issue of the Canadian Journal of Addiction, fentanyl and the other high potency synthetics are here to stay and require a more coherent and comprehensive treatment approach rather than the current piecemeal one. What is also increasingly apparent is that a predominantly biomedical approach alone will also not be effective. The interesting paper by Conway et al,7 also in this issue, identifies that the provision of safer supply prescription opioids did not appear to change the use of illicit drugs and that about 50% of the prescription opioids were taken irregularly or not at all. However, they may have been associated with slightly lower opioid overdose events and mortality rates. Buprenorphine and methadone are WHO essential medicines with demonstrated efficacy, reducing all-cause mortality and overdose in persons with opioid use disorder (OUD) while retained on Opioid Agonist Therapy (OAT).8,9 However, barriers to accessing OAT remain and up to half of persons started on OAT are not retained in treatment at 6 months.10 Addressing the often-complex psychological and social needs of our patients with frequent in-person contact to help them in the recovery process and avert potential relapse needs to become more part of daily addiction medicine practice again to enhance retention and long-term outcomes. Potentially, it was the ongoing provision of care that led to the trend in reduced overdose and mortality found by Conway et al,7 rather than the safer supply. Taken together, it appears clear that although evidence-based prescribing does play a major role in addiction treatment, especially with indicated pharmacotherapies, a predominantly biomedical approach will not work, just as policies that perpetuate the War on Drugs by predominantly focusing on enforcement also have not. The core work of addiction medicine remains direct and active, talking with the people we see to engage them where they are at, trying to address their often-complex biopsychosocial needs supportively, working with them to change their behaviors over time, and keeping them retained in follow-up care, knowing that addiction is a chronic disorder prone to relapse.