{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T00:53:24Z","timestamp":1781657604864,"version":"3.54.5"},"reference-count":0,"publisher":"Diving and Hyperbaric Medicine Journal","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diving Hyperb Med"],"abstract":"<jats:p>Introduction: During clinical use of extracorporeal membrane oxygenation (ECMO) in hyperbaric conditions at our centre, upward titration of indicated sweep gas flow rates is required to maintain adequate CO2 clearance. This project measured the impact of hyperbaric pressure on oxygen flow rates delivered by the Comweld Ezi-Flow flowmeters used in our centre. \nMethods: Oxygen flow rates through Comweld Ezi-flow standard and low oxygen gas flowmeters were set at 101.3 kPa (1 atmosphere absolute [atm abs]) and then measured at intervals up to 284 kPa (2.8 atm abs) using a calibrated gas flow analyser, with cross verification against a small Douglas bag test type apparatus. During testing, the chamber was compressed and decompressed at a rate of 10 kPa\u00b7min-1. Flow rates during chamber compression and decompression were compared.\nResults: The indicated rate of oxygen gas flow through the unadjusted flowmeters changed minimally \u2013 typically rising by a maximum of half of the diameter of the indicator ball. The actual (volumetric) flow, tested across indicated flow rates from 3 to 12 L\u00b7min-1, was consistently reduced by approximately 50% as the chamber pressure increased from 101.3 to 284 kPa (1 to 2.8 atm abs). A slightly smaller reduction was observed when assessing the low flowmeter across the same pressure range; reductions of 40.0 and 43.3% were demonstrated at 0.3 to 0.6 L\u00b7min-1 respectively. Differences in flow rates between compression and decompression were minor except at the very lowest flows.\nConclusions: At 284 kPa (2.8 atm abs), actual volumetric flow of oxygen through Comweld Ezi-Flow flowmeters is dramatically reduced and this needs appropriate compensation to ensure therapeutic aims are achieved.<\/jats:p>","DOI":"10.28920\/dhm56.2.154-160","type":"journal-article","created":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T00:04:32Z","timestamp":1781654672000},"page":"154-160","source":"Crossref","is-referenced-by-count":0,"title":["Quantifying discrepancy between indicated and actual oxygen flow rates delivered by Comweld Ezi-flow low and standard flowmeters under hyperbaric conditions: a technical report"],"prefix":"10.28920","volume":"56","author":[{"given":"Yoav","family":"Aufgang","sequence":"first","affiliation":[{"name":"Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia, School of Translational Medicine, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6521-418X","authenticated-orcid":false,"given":"Bridget","family":"Devaney","sequence":"additional","affiliation":[{"name":"Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia, Emergency and Trauma Centre, Alfred Health, Melbourne, Australia, School of Public Health and Preventive Medicine, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason","family":"Chan","sequence":"additional","affiliation":[{"name":"Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia,  School of Translational Medicine, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ian","family":"Millar","sequence":"additional","affiliation":[{"name":"Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia, School of Public Health and Preventive Medicine, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theo","family":"Tsouras","sequence":"additional","affiliation":[{"name":"Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"11463","published-online":{"date-parts":[[2026,6,30]]},"container-title":["Diving and Hyperbaric Medicine Journal"],"original-title":[],"deposited":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T00:04:34Z","timestamp":1781654674000},"score":1,"resource":{"primary":{"URL":"https:\/\/dhmjournal.com\/index.php?option=com_content&view=article&id=424"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,30]]},"references-count":0,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,6,30]]}},"URL":"https:\/\/doi.org\/10.28920\/dhm56.2.154-160","relation":{},"ISSN":["2209-1491"],"issn-type":[{"value":"2209-1491","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,30]]}}}