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Background: There is limited published data on the caseload of general surgeons in Central Australia. The region has a significant Indigenous population, who often face higher rates of chronic diseases and require more frequent surgical interventions compared to non-Indigenous individuals. This study aims to outline the workload of surgeons at Alice Springs Hospital to determine the necessary skill set and surgical education for future surgeons., Methods: A retrospective review of all general surgery operative cases performed in Central Australia, Alice Springs Hospital was conducted between January 2012 and December 2021. The RACS Morbidity Audit and Logbook Tool was used to classify surgical procedures along with Medicare Benefits Schedule item numbers. Tables were created to present the annual and specialty-specific data on the types and volumes of procedures., Results: From January 2012 to December 2021, 35 318 cases were performed, with 92.5% being general surgery, 3% plastics and reconstructive surgery and 2.8% vascular procedures. Indigenous patients received a higher proportion of procedures (50-60%) compared to non-Indigenous patients (30-50%). Common procedures included incision and drainage of abscesses and debridement of wounds, while trends across specialties showed a decline in ENT and plastic surgeries, stable thoracic and vascular cases, and increased numbers of urology operations., Conclusion: General surgeons in rural centres must possess a wide range of skills and be capable of performing a variety of procedures. Trainees should be encouraged to consider practicing in rural areas, and those interested should account for the specific needs of the communities they plan to serve., (© 2024 Royal Australasian College of Surgeons.)

Background: Intravenous (IV) vasopressors are the mainstay of physiological support for hemodynamically unstable patients. However, the role of oral vasopressors remains unclear. The objective of our study was to evaluate the feasibility of evaluating midodrine for critically ill patients with IV vasopressor-dependent shock., Methods: We conducted a single-center, concealed-allocation, parallel-group, blinded feasibility randomized controlled trial (RCT) evaluating the effect of oral midodrine versus placebo on IV vasopressor-dependent shock in the intensive care unit (ICU). The study was performed in a medical-surgical ICU at the University of Alberta Hospital from April 2021 to July 2022. We included patients aged 18 years or older admitted to the ICU with ongoing vasopressor support with decreasing vasopressor dose(s). Patients were randomly assigned 1:1 to midodrine or a placebo for the duration of their IV vasopressor therapy. The primary outcome was study feasibility and secondary outcomes included patient-centered outcomes. Feasibility was assessed through rate of recruitment, adherence to study protocol, and patient safety., Results: Twenty patients were enrolled in the study and underwent randomization (n = 11 midodrine, n = 9 control). Recruitment was recorded at 1.2 participants per month, protocol adherence was 90%, and allocation remained concealed. No adverse events were reported in either group. Sepsis was the most common cause of shock in both groups. The midodrine group had a shorter length of ICU stay of 9.6 (SD 8.7) vs 10.4 (SD 14.5) days. Hospital mortality was lower for the midodrine group (n = 2, 18.2% vs n = 4, 37.5%). Vasopressor re-initiation after 24 h was more frequent in the midodrine group (n = 4, 36.4% vs n = 2, 25%). There were no readmissions to the ICU following discharge in either group., Conclusions: The evaluation of midodrine for patients in the ICU is feasible and safe. This trial will inform future large-scale RCTs regarding the utility of midodrine in critically ill patients with IV vasopressor-dependent shock., Trial Registration: This pilot RCT was registered at clinicaltrials.gov (NCT04489589). Registered July 27, 2020. https://clinicaltrials.gov/study/NCT04489589., Competing Interests: Declarations. Ethics approval and consent to participate: This trial was approved by the local Research Ethics Board (REB) in August 2020 (Pro00096716). Informed consent was obtained from the patient or surrogate decision-maker (SDM) prior to being enrolled in the study. Consent for publication: Not applicable. Competing interests: The authors declare that they have no competing interests., (© 2024. The Author(s).)

Purpose: Although health research in Canada is primarily conducted in academic hospitals, most patients receive their care in community hospitals. The benefits of increasing research capacity in community hospitals include improved study recruitment, increased generalizability of results, broader patient access to novel therapies, better patient outcomes, enhanced staff satisfaction, and improved organizational efficiency. Nevertheless, building research programs in community hospitals remains challenging because of a lack of support and expertise. To address this gap, we developed a toolkit to help community hospital professionals build and sustain their community hospital research programs., Source: The toolkit was developed by the Canadian Community Intensive Care Unit Research Network (CCIRNet), a group of clinician-researchers and research staff from community hospitals across Canada who have experience building community hospital research programs. Feedback from a concurrent qualitative study of Canadian community critical care professionals informed the toolkit's design., Principal Findings: The CCIRNet toolkit outlines five stages of community hospital clinical research program development: 1) building a research team and gaining support, 2) developing a new research program, 3) choosing a first research study, 4) getting the study up and running, and 5) sustaining a research program. Feedback from qualitative interviews emphasized the need for a step-by-step approach, frequently asked questions, and essential resources. Accordingly, each stage is structured in a question-and-answer format and includes relevant resources for each section., Conclusion: The CCIRNet toolkit is a practical resource for establishing research programs in community hospitals. The toolkit may increase research participation and support clinical research capacity building in community hospitals., (© 2024. The Author(s).)

Background: Acute myocardial infarction (AMI) usually presents in older populations, in which there are established demographic and outcome differences for ST-elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI). No similar comparisons for AMI in the young population exist., Methods: We compared all index NSTEMI and STEMI hospitalizations in young (18-45 years) patients who required revascularization in Alberta, Canada. Outcomes were survival to discharge, and a composite of heart failure hospitalization, cardiac arrest hospitalization, and all-cause mortality at 1 and 5 years., Results: There were 1679 patients included with an index AMI who required revascularization: 655 (39.0%) NSTEMI and 1024 (61.0%) STEMI. The population was disproportionately male (86%), particularly in STEMI patients (87.3%). Marked dyslipidemia (35%) and active smoking (42%) were common, with similar rates among groups. Percutaneous coronary intervention was used in 98.7% of STEMI and 91.5% of NSTEMI patients (P < 0.001), with the remainder who underwent surgical revascularization. The in-hospital mortality rate during index AMI was higher in STEMI compared with NSTEMI patients (1.7% vs 0%; P < 0.001). The rates of the composite outcome were similar for both groups at 1 and 5 years of follow-up in patients who survived to index hospital discharge. After adjusting for sex, age, heart failure and/or cardiac arrest at index AMI, outcomes remained similar among groups at 1 and 5 years., Conclusions: In young patients with AMI, STEMI was a disproportionately male phenomenon and associated with higher mortality at index hospitalization. One-year and 5-year outcomes were similar among STEMI and NSTEMI patients in those discharged alive at index AMI. Smoking and dyslipidemia appear to be major risk factors in the young., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: Opioids remain the mainstay of analgesia for critically ill patients, but its exposure is associated with negative effects including persistent use after discharge. Nonsteroidal anti-inflammatory drugs (NSAIDs) may be an effective alternative to opioids with fewer adverse effects. We aimed to describe beliefs and attitudes towards the use of NSAIDs in adult intensive care units (ICUs)., Methods: Our survey of Canadian ICU physicians was conducted using a web-based platform and distributed through the Canadian Critical Care Society (CCCS) email distribution list. We used previously described survey development methodology including question generation and reduction, pretesting, and clinical sensibility and pilot testing., Results: We received 115 completed surveys from 321 CCCS members (36%). Nonsteroidal anti-inflammatory drugs use was most described as "rarely" (59 respondents, 51%) with the primary concern being adverse events (acute kidney injury [108 respondents, 94%] and gastrointestinal bleeding [92 respondents, 80%]). The primary preferred analgesic was acetaminophen (75 respondents, 65%) followed by opioids (40 respondents, 35%). Most respondents (91 respondents, 80%) would be willing to participate in a randomized controlled trial examining NSAID use in critical care., Conclusions: In our survey, Canadian critical care physicians did not mention commonly using NSAIDs primarily because of concerns about adverse events. Nevertheless, respondents were interested in further studying ketorolac, a commonly used NSAID outside of the ICU, in critically ill patients., (© 2024. Canadian Anesthesiologists' Society.)

Background: Despite the high rates of cholecystectomy in Australia, there is minimal literature regarding the outcomes of cholecystectomy in rural Central Australia within the Northern Territory. This study aims to better characterize the outcomes for patients undergoing cholecystectomy in Central Australia and review clinical and patient characteristics, which may affect outcomes., Method: A retrospective case-control study was performed using data obtained from medical records for all patients undergoing cholecystectomy at Alice Springs Hospital in the Northern Territory from January 2018 until December 2022. Patient characteristics were gathered, and key outcomes examined included: inpatient mortality and 30-day mortality, bile duct injury, bile leak, return to theatre, conversion to open, duration of procedure, length of stay, and up-transfer to a tertiary referral centre., Results: A total of 466 patients were included in this study. Majority of the patients were female and there was a large portion of Indigenous Australians (56%). There were no inpatient mortalities, or 30-day mortalities recorded. There were two bile leaks and/or bile duct injuries (0.4%) and two unplanned returned to theatres (0.4%). Indigenous Australians were more likely to require an emergency operation and had a longer median length of stay (P < 0.001)., Conclusion: Cholecystectomy can be performed safely and to a high standard in Central Australia. Surgeons in Central Australia must appreciate the nuances in the management of patients who come from a significantly different socioeconomic background, with complex medical conditions when compared to metropolitan centres., (© 2024 Royal Australasian College of Surgeons.)

Purpose: The Finke Desert Race is an offroad motorbike and buggy race held annually in central Australia. Owing to the treacherous conditions, this race sees a significant influx of trauma presentations to Alice Springs Hospital, the closest rural hospital. Completion of a tertiary trauma survey (TTS) within 24 hours of a patient's admission is part of standard trauma management., Method: A retrospective analysis was undertaken of trauma presentations managed by general surgery over a 5-day period of the Finke Desert Race weekend, compared to a 3-month control period from February to April of the same year. To be included, patients met the criteria for completion of a TTS., Results: The total number of trauma presentations over the 5-day period of the race weekend was 18 (an incidence rate of 3.6 cases/day), compared to a total of 31 in the 3-month control period (an incidence rate of 0.36 cases/day). The daily rate of major trauma presentations during the Finke race weekend was 9.9 times greater than during the control period. Completion of TTS was missed in only 5.6 % of patients over the Finke weekend, compared to 14.3 % of patients in the control period. The median time from presentation to the emergency department to completion of TTS during the Finke weekend was 20 h 19 min, compared to 20 h 36 min during the control period., Conclusion: Despite the substantial influx of trauma during the race weekend, fewer patients missed having a TTS completed compared to the control period. The median time taken to completion of TTS was similar between the two time periods. These findings suggest that the general surgery department was able to maintain standard trauma management principles., Competing Interests: The authors have no conflicts of interest to declare., (© 2024 The Authors.)

Purpose: Critical care research in Canada is conducted primarily in academically affiliated intensive care units (ICUs) with established research infrastructure. Efforts are made to engage community hospital ICUs in research, although the impacts of their inclusion in clinical research have never been explicitly quantified. We therefore sought to determine the number of additional eligible patients that could be recruited into critical care trials and the change in time to study completion if community ICUs were included in clinical research., Methods: We conducted a decision tree analysis using 2018 Alberta Health Services data. Patient demographics and clinical characteristics for all ICU patients were compared against eligibility criteria from ten landmark, randomized, multicentre critical care trials. Individual patients from academic and community ICUs were assessed for eligibility in each of the ten studies, and decision tree analysis models were built based on prior inclusion and exclusion criteria from those trials., Results: The number of potentially eligible patients for the ten trials ranged from 2,082 to 10,157. Potentially eligible participants from community ICUs accounted for 40.0% of total potentially eligible participants. The recruitment of community ICU patients in trials would have increased potential enrolment by an average of 64.0%. The inclusion of community ICU patients was predicted to decrease time to trial completion by a mean of 14 months (43% reduction)., Conclusion: Inclusion of community ICU patients in critical care research trials has the potential to substantially increase enrolment and decrease time to trial completion., (© 2023. Canadian Anesthesiologists' Society.)

While opioids are part of usual care for analgesia in the ICU, there are concerns regarding excess use. This is a systematic review of nonsteroidal anti-inflammatory drugs (NSAIDs) use in postoperative critical care adult patients., Data Sources: We searched Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, trial registries, Google Scholar, and relevant systematic reviews through March 2023., Study Selection: Titles, abstracts, and full texts were reviewed independently and induplicate by two investigators to identify eligible studies. We included randomized control trials (RCTs) that compared NSAIDs alone or as an adjunct to opioids for systemic analgesia. The primary outcome was opioid utilization., Data Extraction: In duplicate, investigators independently extracted study characteristics, patient demographics, intervention details, and outcomes of interest using predefined abstraction forms. Statistical analyses were conducted using Review Manager software Version 5.4. (The Cochrane Collaboration, Copenhagen, Denmark)., Data Synthesis: We included 15 RCTs ( n = 1,621 patients) for admission to the ICU for postoperative management after elective procedures. Adjunctive NSAID therapy to opioids reduced 24-hour oral morphine equivalent consumption by 21.4 mg (95% CI, 11.8-31.0 mg reduction; high certainty) and probably reduced pain scores (measured by Visual Analog Scale) by 6.1 mm (95% CI, 12.2 decrease to 0.1 increase; moderate certainty). Adjunctive NSAID therapy probably had no impact on the duration of mechanical ventilation (1.6 hr reduction; 95% CI, 0.4 hr to 2.7 reduction; moderate certainty) and may have no impact on ICU length of stay (2.1 hr reduction; 95% CI, 6.1 hr reduction to 2.0 hr increase; low certainty). Variability in reporting adverse outcomes (e.g., gastrointestinal bleeding, acute kidney injury) precluded their meta-analysis., Conclusions: In postoperative critical care adult patients, systemic NSAIDs reduced opioid use and probably reduced pain scores. However, the evidence is uncertain for the duration of mechanical ventilation or ICU length of stay. Further research is required to characterize the prevalence of NSAID-related adverse outcomes., (Copyright © 2023 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)

Background: Type 2 myocardial infarction (T2MI) occurs when myocardial oxygen demand exceeds myocardial oxygen supply. T2MIs occur more frequently and have worse outcomes compared to Type 1 myocardial infarction caused by an acute plaque rupture. No clinical trial evidence is available to guide pharmacological therapies in this high-risk population., Methods: The Rivaroxaban in Type 2 Myocardial Infarction (R2MI) trial (NCT04838808) was a trainee-led, pragmatic, pilot study that randomised patients with a T2MI to either rivaroxaban 2.5 mg twice daily or placebo. The trial was stopped early due to low recruitment. Investigators explored the challenges of conducting the trial in this population. This was supplemented by a retrospective chart review of 10,000 consecutive troponin assays undertaken during the study period., Results: Over a 1-year period, 276 patients with T2MI were screened for inclusion of which only 7 (2.5%) were randomised in the trial. Study investigators identified trial design and participant population factors that limited recruitment. These included: heterogeneity of patient presentation, poor clinical prognosis, and lack of dedicated non-trainee study personnel. The major limitation to recruitment was the frequency of identified exclusion criterion. The retrospective chart review identified 1715 patients with an elevated high-sensitivity troponin level, of which 916 (53%) were adjudicated to be related to T2MI. Of these, 94.5% possessed an exclusion criterion for the trial., Conclusion: Patients with a T2MI are challenging to recruit into clinical trials involving oral anticoagulation. Future studies should account for only ∼1 in every 20 screened individuals being a candidate for study recruitment., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:All authors declare no conflict of interest. This work was funded from a competitive research grant competition – the CCS-Bayer Cardiovascular Research Award which was awarded to Pishoy Gouda. The sponsor had no input in the design or conduct of the study., (© 2023 The Authors.)

Introduction: Intensive care unit (ICU) lengths of stay are modified by ongoing need for haemodynamic support in critically ill patients. This is most commonly provided by intravenous vasopressor therapy. Midodrine has been used as an oral agent for haemodynamic support in patients with orthostatic hypotension or cirrhosis. However, its efficacy in treating shock in the ICU, particularly for patients weaning from intravenous vasopressors, remains uncertain. The objective of this systematic review is to determine the efficacy of midodrine in vasopressor dependent shock., Methods and Analysis: We will search Ovid MEDLINE, Ovid Embase, CINAHL and Cochrane Library for observational trials and randomised controlled trials evaluating midodrine in critically ill patients from inception to 21 April 2022. We will also review unpublished data and relevant conference abstracts. Outcomes will include ICU length of stay, duration of intravenous vasopressor support, ICU mortality, hospital mortality, hospital length of stay and rates of ICU readmission. Data will be analysed in aggregate, where appropriate. We will evaluate risk of bias using the modified Cochrane tool and certainty of evidence using Grading of Recommendations, Assessment, Development and Evaluations methodology. We will perform trial sequential analysis for the outcome of ICU length of stay., Ethics and Dissemination: Ethics approval is not required as primary data will not be collected. Findings of this review will be disseminated through peer-related publication and will inform future clinical trials., Prospero Registration Number: CRD42021260375., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Critical care research in Canada is conducted primarily in academically-affiliated intensive care units with established research infrastructure, including research coordinators (RCs). Recently, efforts have been made to engage community hospital ICUs in research albeit with barriers. Automation or artificial intelligence (AI) could aid the performance of routine research tasks. It is unclear which research study processes might be improved through AI automation., Methods: We conducted a cross-sectional survey of Canadian ICU research personnel. The survey contained items characterizing opinions regarding research processes that may be amenable to AI automation. We distributed the questionnaire via email distribution lists of 3 Canadian research societies. Open-ended questions were analyzed using a thematic content analysis approach., Results: A total of 49 survey responses were received (response rate: 8%). Tasks that respondents felt were time-consuming/tedious/tiresome included: screening for potentially eligible patients (74%), inputting data into case report forms (65%), and preparing internal tracking logs (53%). Tasks that respondents felt could be performed by AI automation included: screening for eligible patients (59%), inputting data into case report forms (55%), preparing internal tracking logs (51%), and randomizing patients into studies (45%). Open-ended questions identified enthusiasm for AI automation to improve information accuracy and efficiency while freeing up RCs to perform tasks that require human interaction. This enthusiasm was tempered by the need for proper AI education and oversight., Conclusions: There were balanced supportive (increased efficiency and re-allocation of tasks) and challenges (informational accuracy and oversight) with regards to AI automation in ICU research.

Bidirectional ventricular tachycardia (BiVT) is a rare form of ventricular tachycardia that manifests on surface electrocardiogram by dual QRS morphologies alternating on a beat-to-beat basis. It was first reported in the 1920s as a complication of digoxin, and since then, it has been reported in other conditions including fulminant myocarditis, sarcoidosis, catecholaminergic polymorphic ventricular tachycardia, and Andersen-Tawil syndrome. The mechanism for BiVT is not as well known as other forms of ventricular tachycardia but appears to include typical mechanisms including triggered activity from afterdepolarizations, abnormal automaticity, or reentry. This review will go beyond the definition, surface electrocardiogram, mechanisms, causes, and treatment of BiVT as per our current understanding., Competing Interests: The authors report no conflicts of interest in this work., (© 2022 Almarzuqi et al.)

A 31-year-old man with primary oxalosis and resultant polyneuropathy presented with worsening leg pain. He was found to have bilateral superficial femoral artery dissections with a non-viable left leg and critically ischaemic right leg. He underwent emergency left above-knee amputation with harvesting of the full-length ipsilateral great saphenous vein (GSV). In a novel technique, the vein was stored for 10 days before being used as conduit in a femoral-popliteal bypass in the contralateral leg. The success of the delayed GSV autograft means the salvage of clinically viable veins in non-viable limbs should be considered when patients present with bilateral acute or critically ischaemic limbs.

Background: Intravenous (IV) vasopressors to support hemodynamics are a primary indication for intensive care unit (ICU) admission. Utilization of oral vasopressor therapy may offer an alternative to IV vasopressor therapy in the ICU, thus decreasing the need for ICU admission. Oral vasopressors, such as midodrine, have been used for hemodynamic support in non-critically ill patients, but their evaluation in critically ill patients to potentially spare IV vasopressor therapy has been limited., Methods: The LIBERATE study will be a multicenter, parallel-group, blinded, randomized placebo-controlled trial. It will recruit adult (i.e., age ≥ 18 years) critically ill patients receiving stable or decreasing doses of IV vasopressors. Eligible patients will be randomized to receive either midodrine 10 mg administered enterally every 8 h or placebo until 24 h post-discontinuation of IV vasopressors. The primary outcome will be ICU length of stay. Secondary outcomes include all-cause mortality at 90 days, hospital length of stay, length of IV vasopressor support, re-initiation of IV vasopressors, rates of ICU readmission, and occurrence of AEs. Health economic outcomes including ICU, hospital and healthcare costs, and cost-effectiveness will be evaluated. Pre-planned subgroup analyses include age, sex, frailty, severity of illness, etiology of shock, and comorbid conditions., Discussion: LIBERATE will rigorously evaluate the effect of oral midodrine on duration of ICU stay and IV vasopressor support in critically ill patients., Trial Registration: ClinicalTrials.gov NCT05058612 . Registered on September 28, 2021., (© 2022. The Author(s).)

Introduction: Advancements in medical and consumer-grade technologies have made it easier than ever to monitor a patient's heart rhythm and to diagnose arrhythmias. Octogenarians with symptomatic arrhythmias have unique management challenges due to their frailty, complex drug interactions, cognitive impairment, and competing comorbidities. The management decisions are further complicated by the lack of randomized evidence to guide treatment., Areas Covered: A comprehensive literature review was undertaken to outline various tachyarrhythmias and bradyarrhythmias and their management, the role of cardiac implantable electronic devices, cardiac ablations, and specific geriatric arrhythmia considerations as recommended in international guidelines., Expert Opinion: Atrial fibrillation (AF) is arguably the most important arrhythmia in the elderly and is associated with significant morbidity and mortality. Early diagnosis of AF, potentially with smart devices (wearables), has the potential to reduce the incidence of stroke, systemic emboli, and the risk of dementia. Bradyarrhythmias have a high incidence in the elderly as well, often requiring implantation of a permanent pacemaker. Leadless pacemakers implanted directly into the right ventricle are great options for gaining traction in elderly patients.

Spontaneous coronary artery dissection (SCAD) is a rare but increasingly recognised cause of acute coronary syndrome. While numerous risk factors are associated with SCAD, one potential cause is coronary artery vasospasm. The use of cabergoline-an ergot derivative and dopamine agonist that may induce vasospasm-has been associated with SCAD in one other case report worldwide. Here, we describe SCAD in a 37-year-old woman on long-term cabergoline therapy with no other cardiac risk factors. Cabergoline-induced SCAD should be considered in patients presenting with an acute coronary syndrome who are treated with this medication., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Predicting successful liberation from mechanical ventilation (MV) in critically ill patients is challenging. Brain natriuretic peptide (BNP) has been proposed to help guide decision-making for readiness to liberate from MV following a spontaneous breathing trial (SBT)., Methods: We performed a systematic review and meta-analysis of randomized and prospective observational studies that measured BNP levels at the time of SBT in patients receiving MV. The primary endpoint was successful liberation from MV (absence of reintubation or non-invasive ventilation at 48 h). Statistical analyses included bi-variate and Moses-Littenberg models and DerSimonian-Laird pooling of areas under ROC curve (AUROC)., Results: A total of 731 articles were screened. Eighteen adult and 2 pediatric studies were fulfilled pre-specified eligibility. The measure of the relative variation of BNP during SBT (ΔBNP%) after exclusion of SBT failure by clinical criteria in adults yielded a sensitivity and specificity of 0.889 [0.831-0.929] and 0.828 [0.730-0.896] for successful liberation from MV, respectively, with a pooled AUROC of 0.92 [0.88-0.97]. The pooled AUROC for any method of analysis for absolute variation of BNP (ΔBNP), pre-SBT BNP, and post-SBT BNP were 0.89 [0.83-0.95], 0.77 [0.63-0.91], and 0.85 [0.80-0.90], respectively., Conclusion: The relative change in BNP during a SBT has potential value as an incremental tool after successful SBT to predict successful liberation from MV in adults. There is insufficient data to support the use of BNP in children or as an alternate test to clinical indices of SBT, or the use of ΔBNP, BNP-pre, and BNP-post as an alternate or incremental test., Trial Registration: PROSPERO CRD42018087474 (6 February 2018).

Introduction: Predicting successful liberation from mechanical ventilation (MV) among critically ill patients receiving MV can be challenging. The current parameters used to predict successful extubation have shown variable predictive value. Brain natriuretic peptide (BNP) has been proposed as a novel biomarker to help guide decision-making in readiness for liberation of MV following a spontaneous breathing trial (SBT). Current evidence on the predictive ability of BNP has been uncertain, and BNP has not been integrated into clinical practice guidelines., Methods and Analysis: We will perform a systematic review and meta-analysis to evaluate the value of BNP during SBT to predict success of liberation from MV. A search strategy will be developed in collaboration with a research librarian, and electronic databases (MEDLINE, EMBASE, Cochrane Library, Web of Science) and additional sources will be searched. Search themes will include: (1) BNP and (2) weaning, extubation and/or liberation from MV. Citation screening, selection, quality assessment and data abstraction will be performed in duplicate. The primary outcome will be liberation from MV; secondary outcomes will include time to reintubation, mortality, MV duration, total and postextubation intensive care unit (ICU) stay, hospitalisation duration, tracheostomy rate, ICU-acquired weakness rate and ventilator-free days. Primary statistical analysis will include predictive value of BNP by receiver operating characteristic curve, sensitivity/specificity and likelihood ratios for combination of BNP and SBT parameters for failure of liberation from MV. Secondary statistical analysis will be performed on individual and combinations of extracted metrics., Ethics and Dissemination: Our review will add knowledge by mapping the current body of evidence on the value of BNP testing for prediction of successful liberation from MV, and describe knowledge gaps and research priorities. Our findings will be disseminated through peer-reviewed publication, presentation at a scientific congress, through regional/national organisations and social media. Research ethics approval is not required., Prospero Registration Number: CRD42018087474., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The DANPACE study suggested implanting dual-pacing dual-sensing dual-response rate-adaptive (DDDR) pacemakers in patients with sick sinus syndrome, even though 90.7% of their atrial-pacing atrial-sensing inhibited-response rate-adaptive (AAIR) group did not require upgrade. Most centers implant DDDR pacemakers due to risk of future atrioventricular (AV) block. Given that AAIR pacemakers are less expensive, have one less lead with potentially one less point of complication, we question whether DDDR pacemakers are superior to AAIR pacemakers. We aim to describe long-term outcomes of AAIR implants., Methods: Patients presenting to the Grey Nuns Hospital in Edmonton, Canada from 1990 to 2012 with sick sinus syndrome without AV block had AAIR pacemakers implanted. Outcomes that were measured over the follow-up time included need for ventricular lead reoperation, incidence of AV block and incidence of sudden cardiac death from AV block., Results: During this period, 330 patients presented with sick sinus syndrome. Eighty-seven (26.4%) patients met criteria for and received AAIR pacemakers. Seventy-eight (91.8%) did not require upgrade over mean follow-up of 10.6 ± 0.6 years. Amongst this group, 31 patients (39.7%) were alive, whereas 47 (60.3%) were deceased at end of follow-up due to other comorbidities. No sudden deaths were attributable to AV block. Only 7 patients (8.2%) required ventricular lead reoperation: 2 (2.4%) presented urgently with symptomatic AV block; 3 (3.5%) had atrial fibrillation requiring beta-blockade; 1 (1.2%) had atrial lead dislodgment; and 1 (1.2%) was electively upgraded at battery end-of-life., Conclusions: This study looks at safety of AAIR pacemakers with only 2.4% of patients developing AV block requiring urgent upgrade. Approximately 91.8% of patients remained with their original AAIR pacemakers (mean follow-up 10.6 vs 5.4 years in DANPACE). Our findings are similar to the DANPACE study but our conclusions are different as we believe AAIR pacing should be considered for selected patients with sick sinus syndrome without AV block.

Purpose: To investigate the hypothesis that some patients are hyperproducers of cholesterol while others are hyperabsorbers by comparing the low-density lipoprotein (LDL) responses to statins versus ezetimibe adjunct therapy., Methods: Consecutive patients (N = 109), who received statin monotherapy followed by ezetimibe adjunct therapy, were prospectively studied. The expected LDL levels for each patient on statin and on ezetimibe adjunct therapy were calculated. The difference between expected and actual LDL levels on statin and on ezetimibe adjunct therapy was calculated for each patient and subsequently correlated., Results: The mean LDL levels (mg/dL) were baseline, 168.7 ± 3.6; on statin, 104.2 ± 2.6; on ezetimibe adjunct, 74.2 ± 2.2. Statins reduced LDL by 36.7 ± 1.5%, while adding ezetimibe resulted in a further reduction of 28.1 ± 1.4%. The percent LDL reduction by statin was negatively correlated to the percent reduction by ezetimibe adjunct therapy (r = -0.29, P = .002). The difference between expected and actual LDL levels on statin was negatively correlated to that on ezetimibe adjunct therapy (r = -0.38, P < .001)., Conclusions: This study demonstrated that the LDL response to ezetimibe is inversely related to the response to statin. This lends support to the hypothesis that some patients may be hyperabsorbers of cholesterol while others may be hyperproducers. This suggests that a less than expected response to the initial dose of statin in a patient would likely require the addition of ezetimibe to achieve the recommended target levels in spite of the use of maximum dose statin therapy.

Introduction: Rapid-access carotid endarterectomy (RACE) is an evidence-based treatment for symptomatic carotid stenosis. Our vascular centre aims to provide this service within 48 h of symptoms in appropriate patients. This study audits safety and efficacy of the first year of RACE., Subjects and Methods: A clear trust protocol was publicised for the RACE pathway. A prospective database was established for all carotid endarterectomies (CEAs) performed. Outcomes were compared between elective (ECE) and rapid-access operations., Results: In 1 year, 96 patients received CE; 20 were performed urgently. There were no significant differences in age or gender between ECE and RACE groups. Twenty-three (30%) of ECE were for asymptomatic stenoses; no other significant differences in surgical indication were seen. Of symptomatic ECE, 43% were for completed stroke versus 55% for RACE. Median delay between diagnosis and surgery was 113 days for elective and 2 days for RACE patients. There was one death following ECE (1.3%) and one stroke after RACE (5%), all not significant. Anaesthetic method did not influence outcome. The main reasons for delaying surgery in RACE patients were optimisation of patient fitness and availability of theatre time., Conclusions: The RACE pathway dramatically reduces delay without compromising patient safety. In the first year of service, we have treated 50% of suitable patients within 48 h. Further education of patients and colleagues should reduce delay and improve outcomes for symptomatic carotid disease.

Background: Although pacemaker manufacturers provide projections on longevity, these projections cannot be relied upon due to the assumptions of output parameters being far in excess of those programmed in clinical practice., Objective: The purpose of this review was to compare the actual longevity to the calculated longevity of pacemakers based on battery cell characteristics taking into account individual programmed parameters, mode, degree of usage, and percent pacing. This was also compared to the manufacturers' own projected longevities., Methods: Patients who had a pacemaker replaced between 1998 and 2003 were included (n = 124). Cell characteristics were obtained from manufacturers and programmed parameters were obtained at each visit. Stepwise calculations were done for each visit to find current drain during each interval, and then were used in a weighted average to find the total average lifetime current drain. This was subsequently used to find a calculated longevity for each pacemaker to be compared to the actual longevity observed., Results: The pacemakers lasted 491+/-92 days (mean+/-SEM) less than calculated. There was also a difference between dual- and single-chamber devices (though not statistically significant). Moreover, it was found that there were significant differences between manufacturers., Conclusions: There appears to be a significant discrepancy between calculated and actual longevities, confirming that battery depletion occurs earlier than expected. This suggests that current drain expended for ancillary functions may be considerable. Another factor may be pre-implantation drain. Vigilance with programming of outputs, modes, sensors, heart rates, and ancillary functions could potentially extend longevity and postpone/obviate the need for costly repeat surgery with its attended risk of complications. Furthermore, the differences between manufacturers seem to parallel the clinical impressions.

Chemokines are important mediators of macrophage and T-cell recruitment in a number of inflammatory pathologies, and chemokines expressed in atherosclerotic lesions may play an important role in mononuclear cell recruitment and macrophage differentiation. We have analyzed the expression of the linked chromosome 16q13 genes that encode macrophage-derived chemokine (MDC/CCL22), thymus- and activation-regulated chemokine (TARC/CCL17), and the CX(3)C chemokine fractalkine (CX(3)CL1) in primary macrophages and human atherosclerotic lesions by reverse transcription-polymerase chain reaction and immunohistochemistry. We show that macrophage expression of the chemokines MDC, fractalkine, and TARC is upregulated by treatment with the Th2-type cytokines interleukin-4 and interleukin-13. High levels of MDC, TARC, and fractalkine mRNA expression are seen in some, but not all, human arteries with advanced atherosclerotic lesions. Immunohistochemistry shows that MDC, fractalkine, and TARC are expressed by a subset of macrophages within regions of plaques that contain plaque microvessels. We conclude that MDC, fractalkine, and TARC, which are chromosome 16q13 chemokines, could play a role in mononuclear cell recruitment into atherosclerotic lesions and influence the subsequent inflammatory response. Macrophage-expressed chemokines upregulated by interleukin-4 may be useful surrogate markers for the presence of Th2-type immune responses in human atherosclerotic lesions.