Regional access to a centralized extracorporeal membrane oxygenation (ECMO) service in Victoria, Australia.

Introduction: Victoria, Australia provides a centralised state ECMO service, supported by ambulance retrieval. Equity of access to this service has not been previously described. Objective: Describe the characteristics of ECMO recipients and quantify geographical and socioeconomic influence on access. Design: Retrospective observational study with spatial mapping. Participants and setting: Adult (≥18 years) ECMO recipients from July 2016-June 2022. Data from administrative Victorian Admissions Episodes Database analysed in conjunction with Australian Urban Research Infrastructure Network population data and choropleth mapping. Presumed ECMO modes were inferred from cardiopulmonary bypass and pre-hospital cardiac arrest codes. Spatial autoregressive models including Moran's test used for spatial lag testing. Outcomes: Demographics and outcomes of ECMO recipients; ECMO incidence by patient residence (Statistical-Area Level 2, SA-2) and Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD); and ECMO utilisation adjusted for patient factors and linear distance from the central ECMO referral site. Results: 631 adults received ECMO over 6 years, after exclusion of paediatric (n = 242), duplicate (n = 135), and interstate or incomplete (n = 72) records. Mean age was 51.8 years, and 68.8 % were male. Overall ECMO incidence was 3.00 ± 3.95 per 105 population. 135 (21.4 %) were presumed VA-ECMO, 59 (9.3 %) presumed ECPR, and 437 (69.3 %) presumed VV-ECMO. Spatial lag was non-significant after adjusting for patient characteristics. Distance from the central referral site (dy/dx = 0.19, 95% CI -0.41-0.04, p = 0.105) and IRSAD score (dy/dx = 0.17, 95% CI -0.19-0.53, p = 0.359) did not predict ECMO utilisation. Conclusion: Victorian ECMO incidence rates were low. We did not find evidence of inequity of access to ECMO irrespective of regional area or socioeconomic status.

Intensive care implications of epidemic thunderstorm asthma.

OBJECTIVE: To investigate the environmental precipitants, treatment and outcome of critically ill patients affected by the largest and most lethal reported epidemic of thunderstorm asthma. DESIGN, SETTING AND PARTICIPANTS: Retrospective multicentre observational study. Meteorological, airborne particulate and pollen data, and a case series of 35 patients admitted to 15 intensive care units (ICUs) due to the thunderstorm asthma event of 21-22 November 2016, in Victoria, Australia, were analysed and compared with 1062 total ICU-admitted Australian patients with asthma in 2016. MAIN OUTCOME MEASURES: Characteristics and outcomes of total ICU versus patients with thunderstorm asthma, the association between airborne particulate counts and storm arrival, and ICU resource utilisation. RESULTS: All 35 patients had an asthma diagnosis; 13 (37%) had a cardiac or respiratory arrest, five (14%) died. Compared with total Australian ICU-admitted patients with asthma in 2016, patients with thunderstorm asthma had a higher mortality (15% v 1.3%, P < 0.001), were more likely to be male (63% v 34%, P < 0.001), to be mechanically ventilated, and had shorter ICU length of stay in survivors (median, 31.8 hours [interquartile range (IQR), 14.8-43.6 hours] v 40.7 hours [IQR, 22.3-75.1 hours]; P = 0.025). Patients with cardiac arrest were more likely to be born in Asian or subcontinental countries (5/10 [50%] v 4/25 [16%]; relative risk, 3.13; 95% CI, 1.05-9.31). A temporal link was demonstrated between airborne particulate counts and arrival of the storm. The event used 15% of the public ICU beds in the region. CONCLUSION: Arrival of a triggering storm is associated with an increase in respirable airborne particles. Affected critically ill patients are young, have a high mortality, a short duration of bronchospasm, and a prior diagnosis of asthma is common.

The Melbourne epidemic thunderstorm asthma event 2016: an investigation of environmental triggers, effect on health services, and patient risk factors.

BACKGROUND: A multidisciplinary collaboration investigated the world's largest, most catastrophic epidemic thunderstorm asthma event that took place in Melbourne, Australia, on Nov 21, 2016, to inform mechanisms and preventive strategies. METHODS: Meteorological and airborne pollen data, satellite-derived vegetation index, ambulance callouts, emergency department presentations, and data on hospital admissions for Nov 21, 2016, as well as leading up to and following the event were collected between Nov 21, 2016, and March 31, 2017, and analysed. We contacted patients who presented during the epidemic thunderstorm asthma event at eight metropolitan health services (each including up to three hospitals) via telephone questionnaire to determine patient characteristics, and investigated outcomes of intensive care unit (ICU) admissions. FINDINGS: Grass pollen concentrations on Nov 21, 2016, were extremely high (>100 grains/m3). At 1800 AEDT, a gust front crossed Melbourne, plunging temperatures 10°C, raising humidity above 70%, and concentrating particulate matter. Within 30 h, there were 3365 (672%) excess respiratory-related presentations to emergency departments, and 476 (992%) excess asthma-related admissions to hospital, especially individuals of Indian or Sri Lankan birth (10% vs 1%, p<0·0001) and south-east Asian birth (8% vs 1%, p<0·0001) compared with previous 3 years. Questionnaire data from 1435 (64%) of 2248 emergency department presentations showed a mean age of 32·0 years (SD 18·6), 56% of whom were male. Only 28% had current doctor-diagnosed asthma. 39% of the presentations were of Asian or Indian ethnicity (25% of the Melbourne population were of this ethnicity according to the 2016 census, relative risk [RR] 1·93, 95% CI 1·74-2·15, p <0·0001). Of ten individuals who died, six were Asian or Indian (RR 4·54, 95% CI 1·28-16·09; p=0·01). 35 individuals were admitted to an intensive care unit, all had asthma, 12 took inhaled preventers, and five died. INTERPRETATION: Convergent environmental factors triggered a thunderstorm asthma epidemic of unprecedented magnitude, tempo, and geographical range and severity on Nov 21, 2016, creating a new benchmark for emergency and health service escalation. Asian or Indian ethnicity and current doctor-diagnosed asthma portended life-threatening exacerbations such as those requiring admission to an ICU. Overall, the findings provide important public health lessons applicable to future event forecasting, health care response coordination, protection of at-risk populations, and medical management of epidemic thunderstorm asthma. FUNDING: None.

Participant perceptions of a rapid response team training course.

BACKGROUND: Rapid response team (RRT) responders would benefit from training, to ensure competent and efficient management of the deteriorating patient. DESIGN, SETTING AND PARTICIPANTS: We obtained delegate feedback on a pilot training course for RRTs, commissioned by the Australian and New Zealand Intensive Care Society (ANZICS), at the second ANZICS: The Deteriorating Patient Conference. METHODS: We surveyed participants on their perceptions of the course overall, and their perceptions of sessions containing presentations and videotaped and live demonstrations of simulated scenarios of patients whose conditions were deteriorating. RESULTS: The survey response rate was 64% (96 of 150 potential attendees). Responses were positive, with 79.8% of responses (912/1143) agreeing that the participants had learnt something new, that the course would increase their confidence and competence during RRT calls, and that it had assisted them as an educator. The course was well received overall, with the interactive and live demonstration components of the course garnering positive feedback in the comments section of surveys. CONCLUSIONS: There was unanimous agreement by participants for further development of a formalised RRT training course for responding to the deteriorating patient. Participants who were RRT educators also supported the development of an RRT train-the-trainer course.