Multiple arterial vs. single arterial coronary artery bypass grafting: sex-related differences in outcomes.

BACKGROUND AND AIMS: Uncertainty exists over whether multiple arterial grafting has a sex-related association with survival after coronary artery bypass grafting. This study aims to compare the long-term survival of using multiple arterial grafting vs. single arterial grafting in women and men undergoing coronary artery bypass grafting. METHODS: The retrospective study used the Australian and New Zealand Society of Cardiothoracic Surgical Database with linkage to the National Death Index. Patients from 2001 to 2020 were identified. Sex-stratified, inverse probability weighted Cox proportional hazard model was used to facilitate survival comparisons. The primary outcome was all-cause mortality. RESULTS: A total number of 54 275 adult patients receiving at least two grafts in primary isolated bypass operations were analysed. The entire study cohort consisted of 10 693 (19.7%) female patients and 29 711 (54.7%) multiple arterial grafting procedures. At a median (interquartile range) postoperative follow-up of 4.9 (2.3-8.4) years, mortality was significantly lower in male patients undergoing multiarterial than single arterial procedures (adjusted hazard ratio 0.82; 95% confidence interval 0.77-0.87; P < .001). The survival benefit was also significant for females (adjusted hazard ratio 0.83; 95% confidence interval 0.76-0.91; P < .001) at a median (interquartile range) follow-up of 5.2 (2.4-8.7) years. The interaction model from Cox regression suggested insignificant subgroup effect from sex (P = .08) on the observed survival advantage. The survival benefits associated with multiple arterial grafting were consistent across all sex-stratified subgroups except for female patients with left main coronary disease. CONCLUSIONS: Compared to single arterial grafting, multiple arterial revascularization is associated with improved long-term survival for women as well as men.

ECPR Survivor Estimates: A Simulation-Based Approach to Comparing ECPR Delivery Strategies.

Objective: The number of out-of-hospital cardiac arrest (OHCA) patients who may benefit from prehospital extracorporeal cardiopulmonary resuscitation (ECPR) is yet to be elucidated. Patient eligibility is determined both by case characteristics and physical proximity to an ECPR service. We applied accessibility principles to historical cardiac arrest data, to identify the number of patients who would have been eligible for prehospital ECPR in Sydney, Australia, and the potential survival benefit had prehospital ECPR been available.Methods: The New South Wales cardiac arrest registry between January 2017 to June 2021 included 39,387 cardiac arrests. We retrospectively defined two groups: 1) possible ECPR eligible arrests that would have triggered activation of a team, and 2) ECPR eligible arrests, those arrests that met ECPR inclusion criteria and remained refractory. Transport accessibility modeling was used to ascertain the number of arrests that would have been served by a hypothetical prehospital service and the potential survival benefit.Results: There were 699 arrests screened as possibly ECPR eligible in the Sydney metropolitan area, 488 of whom were subsequently confirmed as ECPR eligible refractory OHCA. Of these, 38% (n = 185) received intra-arrest transfer to hospital, with 37% (n = 180) arriving within 60 min. Using spatial and transport modeling, a prehospital team located at an optimal location could establish 437 (90%) patients onto ECMO within 60 min, with an estimated survival of 48% (IQR 38-57). Based on existing survival curves, compared to conventional CPR, an optimally located prehospital ECPR service has the potential to save one additional life for every 3.0 patients.Conclusions: A significant number of historical OHCA patients could have benefited from prehospital ECPR, with a potential survival benefit above conventional CPR.

From a Position of Known Angiographic Perfect Patency: What Happens Next?

BACKGROUND AND AIM: The biological behaviour of coronary graft conduits over time may be considered by serial angiography. METHODS: A single institution retrospective cohort received mostly clinically indicated angiography between 1997 and 2020, following coronary bypass surgery. Only perfectly patent grafts (absence of any lumen irregularity) for each conduit type at the first postoperative angiogram were selected for a later comparison. The latest angiograms were at least 5 years postoperatively, and at least 1 year after first postoperative angiogram. Analysis was done according to each graft (anastomosis). Comparisons used generalised estimating equations, adjusted for binary logistic regression. RESULTS: Of 143 patients, there were 410 of 468 (87.6%) perfectly patent grafts at the first angiogram, analysed at 6.8±4.0 years postoperative, of which 157 were internal mammary arteries, 228 were radial arteries, and 25 were saphenous veins. At the latest angiogram (12.2±3.8 years postoperative), comparison with the first angiogram for each individual graft found preserved perfect patency for internal mammary arteries, 156 of 157 (99.4%), and for radial arteries, 227 of 228 (99.6%) but saphenous veins deteriorated considerably, 13 of 25 (52.0%). The two arterial grafts (internal mammary and radial) were superior to vein grafts (odds ratio 163; 95% confidence interval [CI] 22-1,211; p<0.001), but not different from each other (odds ratio 0.95; 95% CI 0.78-1.16; p=0.584). CONCLUSIONS: From a position of known angiographic perfect patency post-CABG, internal mammary artery and radial artery grafts retained their perfect patency in the longer term, but saphenous vein grafts did not.

Oxygenation during the apnoeic phase preceding intubation in adults in prehospital, emergency department, intensive care and operating theatre environments.

BACKGROUND: Apnoeic oxygenation is the delivery of oxygen during the apnoeic phase preceding intubation. It is used to prevent respiratory complications of endotracheal intubation that have the potential to lead to significant adverse events including dysrhythmia, haemodynamic decompensation, hypoxic brain injury and death. Oxygen delivered by nasal cannulae during the apnoeic phase of intubation (apnoeic oxygenation) may serve as a non-invasive adjunct to endotracheal intubation to decrease the incidence of hypoxaemia, morbidity and mortality. OBJECTIVES: To evaluate the benefits and harms of apnoeic oxygenation before intubation in adults in the prehospital, emergency department, intensive care unit and operating theatre environments compared to no apnoeic oxygenation during intubation. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 4 November 2022. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs that compared the use of any form of apnoeic oxygenation including high flow and low flow nasal cannulae versus no apnoeic oxygenation during intubation. We defined quasi-randomization as participant allocation to each arm by means that were not truly random, such as alternation, case record number or date of birth. We excluded comparative prospective cohort and comparative retrospective cohort studies, physiological modelling studies and case reports. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. hospital stay and 2. incidence of severe hypoxaemia. Our secondary outcomes were 3. incidence of hypoxaemia, 4. lowest recorded saturation of pulse oximetry (SpO2), 5. intensive care unit (ICU) stay, 6. first pass success rate, 7. adverse events and 8. MORTALITY: We used GRADE to assess certainty of evidence. MAIN RESULTS: We included 23 RCTs (2264 participants) in our analyses. Eight studies (729 participants) investigated the use of low-flow (15 L/minute or less), and 15 studies (1535 participants) investigated the use of high-flow (greater than 15 L/minute) oxygen. Settings were varied and included the emergency department (2 studies, 327 participants), ICU (7 studies, 913 participants) and operating theatre (14 studies, 1024 participants). We considered two studies to be at low risk of bias across all domains. None of the studies reported on hospital length of stay. In predominately critically ill people, there may be little to no difference in the incidence of severe hypoxaemia (SpO2 less than 80%) when using apnoeic oxygenation at any flow rate from the start of apnoea until successful intubation (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.66 to 1.11; P = 0.25, I² = 0%; 15 studies, 1802 participants; low-certainty evidence). There was insufficient evidence of any effect on the incidence of hypoxaemia (SpO2 less than 93%) (RR 0.58, 95% CI 0.23 to 1.46; P = 0.25, I² = 36%; 3 studies, 489 participants; low-certainty evidence). There may be an improvement in the lowest recorded oxygen saturation, with a mean increase of 1.9% (95% CI 0.75% to 3.05%; P < 0.001, I² = 86%; 15 studies, 1525 participants; low-certainty evidence). There may be a reduction in the duration of ICU stay with the use of apnoeic oxygenation during intubation (mean difference (MD) ‒1.13 days, 95% CI ‒1.51 to ‒0.74; P < 0.0001, I² = 46%; 5 studies, 815 participants; low-certainty evidence). There may be little to no difference in first pass success rate (RR 1.00, 95% CI 0.93 to 1.08; P = 0.79, I² = 0%; 8 studies, 826 participants; moderate-certainty evidence). There may be little to no difference in incidence of adverse events including oral trauma, arrhythmia, aspiration, hypotension, pneumonia and cardiac arrest when apnoeic oxygenation is used. There was insufficient evidence about any effect on mortality (RR 0.84, 95% CI 0.70 to 1.00; P = 0.06, I² = 0%; 6 studies, 1015 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: There was some evidence that oxygenation during the apnoeic phase of intubation may improve the lowest recorded oxygen saturation. However, the differences in oxygen saturation were unlikely to be clinically significant. This did not translate into any measurable effect on the incidence of hypoxaemia or severe hypoxaemia in a group of predominately critically ill people. We were unable to assess the influence on hospital length of stay; however, there was a reduction in ICU stay in the apnoeic oxygenation group. The mechanism for this is unclear as there was little to no difference in first pass success or adverse event rates.

Prehospital Extracorporeal Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis.

OBJECTIVES: To evaluate the available published evidence of the effects of extracorporeal cardiopulmonary resuscitation (ECPR) in the prehospital setting on clinical outcomes in patients with out-of-hospital cardiac arrest. DESIGN: A systematic review and meta-analysis designed according to the Preferred Reporting Items for Systematic Reviews an Meta-Analyses guidelines. SETTING: In the prehospital setting. PARTICIPANTS: All randomized control trials (RCTs) and observational trials using pre-hospital ECPR in adult patients (>17 years). INTERVENTIONS: Prehospital ECPR. MEASUREMENTS AND MAIN RESULTS: The study authors searched Medline, Embase, and PUBMED for all RCTs and observational trials. The studies were assessed for clinical, methodologic, and statistical heterogeneity. The primary outcome was survival at hospital discharge. The study outcomes were aggregated using random-effects meta-analysis of means or proportions as appropriate. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence. Four studies were included, with a total of 222 patients receiving prehospital ECPR (mean age = 51 years [95% CI 44-57], 81% of patients were male (CI 74-87), and 60% patients had a cardiac cause for their arrest (95% CI 43-76). Overall survival at discharge was 23.4% (95% CI 15.5-33.7; I2 = 62%). The pooled low-flow time was 61.1 minutes (95% CI 45.2-77.0; I2 = 97%). The quality of evidence was assessed to be low, and the overall risk of bias was assessed to be serious, with confounding being the primary source of bias. CONCLUSION: No definitive conclusions can be made as to the efficacy of prehospital ECPR in refractory cardiac arrest. Higher quality evidence is required.

Barriers and facilitators to achieving competence in lung ultrasound: A survey of physiotherapists following a lung ultrasound training course.

BACKGROUND AND PURPOSE: Lung ultrasound (LUS) is an emerging tool for acute respiratory physiotherapists. In Australia, there are a select few LUS training courses run for physiotherapists. Research to date has evaluated LUS training courses for physiotherapists in terms of knowledge and skill acquisition. The impact of LUS training on user competence and confidence and whether LUS is used in clinical practice has yet to be evaluated. This study therefore explored the impact of attending a physiotherapy LUS training course on acquisition of competence and confidence and the barriers and facilitators for physiotherapists in achieving competence in LUS. METHODS: A quantitative survey containing 21 questions was distributed to 77 Australian physiotherapists. RESULTS: Of the invited physiotherapists, 39 (50%) completed the survey. Most participants were working in intensive care, in the public hospital setting. Binary logistic regression was performed and demonstrated no significant difference in the relationship between years of clinical experience and having confidence in performing or interpreting LUS images. There was also no statistical significance in the relationship between years of clinical experience and gaining competence and accreditation in LUS. Of the 39 responders, 20 physiotherapists had performed at least one LUS scan since completing training; however, most identified they never use LUS to inform clinical decision-making. Only one physiotherapist had gained accreditation through an ultrasound-governing body. The most frequently reported barriers to achieving competence were lack of clinical time to devote to training and lack of an LUS supervisor. CONCLUSION: A majority of physiotherapists who participated in an LUS training course did not attain competence or accreditation, nor were they confident in performing LUS and interpreting images. Barriers exist that prevent intensive care physiotherapists from being able to use LUS in clinical practice. LUS is also not frequently used by acute respiratory physiotherapists to make clinical decisions.

Interrater reliability in assigning a lung ultrasound score.

BACKGROUND AND PURPOSE: Lung ultrasound (LUS) for physiotherapists is an emerging bedside tool. The LUS score of aeration presents as a possible means of assessing and monitoring lung aeration associated with respiratory physiotherapy treatments. There are no studies to date that have assessed the interrater reliability (IRR) of physiotherapists assigning the LUS score of aeration. This study assessed the IRR of assigning the LUS score among adult, mechanically ventilated patients in an intensive care unit with a clinical suspicion of acute lobar atelectasis. METHODS: A convenience sample of patients had an LUS performed by a physiotherapist, and images were independently reviewed by two physiotherapists. Each lung zone was assigned an LUS score between 0 and 3 (with 0 being normal aeration and 3 being complete consolidation, presence of effusion, or pneumothorax). IRR was assessed using the kappa statistic. RESULTS: A total of 1032 LUS images were obtained. Assigning of the LUS across all lung zones demonstrated substantial agreement with kappa 0.685 (95% confidence interval: 0.650, 0.720). Right (0.702 [0.653, 0.751]) and left (0.670 [0.619, 0.721]) lung zones also demonstrated substantial agreement. CONCLUSION: We found substantial IRR between physiotherapists in assigning the LUS score in a mechanically ventilated adult population in the intensive care unit. AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRATION NUMBER: ACTRN12619000783123.

Job satisfaction and symptoms of depression, anxiety, stress, and burnout: A survey of Australian and New Zealand intensive care research coordinators.

INTRODUCTION: Intensive care unit clinical research is often implemented by specialised research coordinators (RCs). Clinical research activity within Australian and New Zealand intensive care units has escalated, particularly during the COVID-19 pandemic. Growth of the intensive care RC workforce to match research demand is poorly understood. AIM: The aim of this study was to repeat an Intensive Care Research Coordinator Interest Group workforce survey conducted in 2004 and 2009 to describe the current workforce and role satisfaction and also to determine reported symptoms of depression, anxiety, stress, and burnout in Australian and New Zealand intensive care RCs. METHODS: In April 2021, an online anonymised survey was distributed to intensive care RCs to complete demographic and workforce questions, the McCloskey/Mueller Satisfaction Scale, the Depression Anxiety Stress Scales-21, and the Maslach Burnout Inventory-Human Services Survey for Medical Personnel. RESULTS: Of 128 Intensive Care Research Coordinator Interest Group eligible members, 98 (77%) completed the survey. Respondents were mainly women (91%), the median age was 47 years, 37% have a postgraduate qualification, and a third have over 10 years of RCC experience (31%). Half do not have permanent employment (52%). The mean Depression Anxiety Stress Scales-21 scores were within the normal range, and respondents reported symptoms of depression (21 [21%]), anxiety (23 [23%]), and stress (26 [27%]). Nearly half of the respondents (44%) exhibited an early symptom of burnout by reporting problematic experiences of work. The overall role satisfaction score was 3.5/5 (neutral; neither satisfied nor dissatisfied). CONCLUSIONS: Intensive care RCs are an experienced group of professionals with limited satisfaction in the role. One-fifth of the ICU RCs experienced depression, anxiety, or stress symptoms, with close to half reporting signs of burnout. These results highlight the need to address areas of concern to ensure retention of this specialised intensive care workforce.

Severe inbreeding, increased mutation load and gene loss-of-function in the critically endangered Devils Hole pupfish.

Small populations with limited range are often threatened by inbreeding and reduced genetic diversity, which can reduce fitness and exacerbate population decline. One of the most extreme natural examples is the Devils Hole pupfish (Cyprinodon diabolis), an iconic and critically endangered species with the smallest known range of any vertebrate. This species has experienced severe declines in population size over the last 30 years and suffered major bottlenecks in 2007 and 2013, when the population shrunk to 38 and 35 individuals, respectively. Here, we analysed 30 resequenced genomes of desert pupfishes from Death Valley, Ash Meadows and surrounding areas to examine the genomic consequences of small population size. We found extremely high levels of inbreeding (FROH = 0.34-0.81) and an increased amount of potentially deleterious genetic variation in the Devils Hole pupfish as compared to other species, including unique, fixed loss-of-function alleles and deletions in genes associated with sperm motility and hypoxia. Additionally, we successfully resequenced a formalin-fixed museum specimen from 1980 and found that the population was already highly inbred prior to recent known bottlenecks. We thus document severe inbreeding and increased mutation load in the Devils Hole pupfish and identify candidate deleterious variants to inform management of this conservation icon.

Coronary artery bypass surgery for acute coronary syndrome: A network meta-analysis of on-pump cardioplegic arrest, off-pump, and on-pump beating heart strategies.

BACKGROUND: Coronary artery bypass grafting (CABG) in the setting of an acute coronary syndrome is a high-risk procedure, and the best strategy for myocardial revascularisation remains debated. This study compares the 30-day mortality benefit of on-pump CABG (ONCAB), off-pump CABG (OPCAB), and on-pump beating heart CABG (OnBHCAB) strategies. METHODS: A systematic search of three electronic databases was conducted for studies comparing ONCAB with OPCAB or OnBHCAB in patients with acute coronary syndrome (ACS). The primary outcome, 30-day mortality, was compared using a Bayesian hierarchical network meta-analysis (NMA). A random effects consistency model was applied, and direct and indirect comparisons were made to determine the relative effectiveness of each strategy on postoperative outcomes. RESULTS: One randomised controlled trial and eighteen observational studies fulfilling the inclusion criteria were identified. A total of 4320, 5559, and 1962 patients underwent ONCAB, OPCAB, and OnBHCAB respectively. NMA showed that OPCAB had the highest probability of ranking as the most effective treatment in terms of 30-day mortality (odds ratio [OR], 0.50; 95% credible interval [CrI], 0.23-1.00), followed by OnBHCAB (OR, 0.62; 95% CrI, 0.20-1.57), however the 95% CrI crossed or included unity. A subgroup NMA of nine studies assessing only acute myocardial infarction (AMI) patients demonstrated a 72% reduction in likelihood of 30-day mortality after OPCAB (CrI, 0.07-0.83). No significant increase in rate of stroke, renal dysfunction or length of intensive care unit stay was found for either strategy. CONCLUSIONS: Although no single best surgical revascularisation approach in ACS patients was identified, the significant mortality benefit with OPCAB seen with AMI suggests high acuity patients may benefit most from avoiding further myocardial injury associated with cardiopulmonary bypass and cardioplegic arrest.