{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T16:25:55Z","timestamp":1784132755953,"version":"3.55.0"},"update-to":[{"DOI":"10.12688\/f1000research.52885.1","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2021,9,20]],"date-time":"2021-09-20T00:00:00Z","timestamp":1632096000000}}],"reference-count":52,"publisher":"F1000 Research Ltd","license":[{"start":{"date-parts":[[2021,9,20]],"date-time":"2021-09-20T00:00:00Z","timestamp":1632096000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002383","name":"King Saud University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002383","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["f1000research.com"],"crossmark-restriction":false},"short-container-title":["F1000Res"],"abstract":"<ns3:p>\n                    <ns3:bold>Background:<\/ns3:bold>\n                    Acute type two respiratory failure (AT2RF) is characterized by high carbon dioxide levels (PaCO\n                    <ns3:sub>2<\/ns3:sub>\n                    &gt;6kPa). Non-invasive ventilation (NIV), the current standard of care, has a high failure rate. High flow nasal therapy (HFNT) has potential additional benefits such as CO\n                    <ns3:sub>2<\/ns3:sub>\n                    clearance, the ability to communicate and comfort. The primary aim of this systematic review is to determine whether HFNT in AT2RF improves 1) PaCO\n                    <ns3:sub>2<\/ns3:sub>\n                    , 2) clinical and patient-centred outcomes and 3) to assess potential harms.\n                  <\/ns3:p>\n                  <ns3:p>\n                    <ns3:bold>Methods:<\/ns3:bold>\n                    We searched EMBASE, MEDLINE and CENTRAL \u00a0(January 1999-January 2021). Randomised controlled trials (RCTs) and cohort studies comparing HFNT with low flow nasal oxygen (LFO) or NIV were included. Two authors independently assessed studies for eligibility, data extraction and risk of bias. We used Cochrane risk of bias tool for RCTs and Ottawa-Newcastle scale for cohort studies.\n                  <\/ns3:p>\n                  <ns3:p>\n                    <ns3:bold>Results:<\/ns3:bold>\n                    From 727 publications reviewed, four RCTs and one cohort study (n=425) were included. In three trials of HFNT vs NIV, comparing PaCO\n                    <ns3:sub>2<\/ns3:sub>\n                    (kPa) at last follow-up time point, there was a significant reduction at four hours\u00a0(1 RCT; HFNT median 6.7, IQR 5.6 \u2013 7.7 vs NIV median 7.6, IQR 6.3 \u2013 9.3) and no significant difference at\u00a0 24-hours or five days. Comparing HFNT with LFO, there was no significant difference at 30-minutes. There was no difference in intubation or mortality.\n                  <\/ns3:p>\n                  <ns3:p>\n                    <ns3:bold>Conclusions:<\/ns3:bold>\n                    This review identified a small number of studies with low to very low certainty of evidence. A reduction of PaCO\n                    <ns3:sub>2<\/ns3:sub>\n                    at an early time point of four hours post-intervention was demonstrated in one small RCT. Significant limitations of the included studies were lack of adequately powered outcomes and clinically relevant time-points and small sample size. Accordingly, systematic review cannot recommend the use of HFNT as the initial management strategy for AT2RF and trials adequately powered to detect clinical and patient-relevant outcomes are urgently warranted.\n                  <\/ns3:p>","DOI":"10.12688\/f1000research.52885.2","type":"journal-article","created":{"date-parts":[[2021,9,20]],"date-time":"2021-09-20T06:07:43Z","timestamp":1632118063000},"page":"482","update-policy":"https:\/\/doi.org\/10.12688\/f1000research.crossmark-policy","source":"Crossref","is-referenced-by-count":7,"title":["High flow nasal oxygen for acute type two respiratory failure: a systematic review"],"prefix":"10.12688","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9234-223X","authenticated-orcid":false,"given":"Asem Abdulaziz","family":"Alnajada","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bronagh","family":"Blackwood","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1551-5800","authenticated-orcid":false,"given":"Abdulmajeed","family":"Mobrad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adeel","family":"Akhtar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivan","family":"Pavlov","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Murali","family":"Shyamsundar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2560","published-online":{"date-parts":[[2021,9,20]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"ii1-ii35","DOI":"10.1136\/thoraxjnl-2015-208209","article-title":"BTS\/ICS guideline for the ventilatory management of acute hypercapnic respiratory failure in adults.","volume":"71","author":"A Davidson","year":"2016","journal-title":"Thorax."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"550-554","DOI":"10.1136\/thorax.55.7.550","article-title":"One year period prevalence study of respiratory acidosis in acute exacerbations of COPD: implications for the provision of non-invasive ventilation and oxygen administration.","volume":"55","author":"P Plant","year":"2000","journal-title":"Thorax."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"43-48","DOI":"10.1136\/thx.2010.153114","article-title":"National Chronic Obstructive Pulmonary Disease Resources and Outcomes Project implementation group. 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status","group":{"name":"current-referee-status","label":"Current Referee Status"}},{"value":"10.5256\/f1000research.56213.r87742, Ben Messer, North East Assisted Ventilation Service, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK, 14 Jul 2021, version 1, 1 approved, 1 approved with reservations","URL":"https:\/\/f1000research.com\/articles\/10-482\/v1#referee-response-87742","order":0,"name":"referee-response-87742","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Asem Alnajada<\/b>; \n<i>Posted: 01 Sep 2021<\/i>; We would like to thank the reviewer for his time in reviewing this manuscript. The comments have been responded to individually as stated below. We feel that the manuscript has improved with his input and hope that he is satisfied by our response and additional changes.  \n<b>C1:<\/b> This is a thorough systematic review which has appropriate methodology and identifies the paucity of evidence available comparing HFNO to NIV. There are minimal differences detectable and no clinically important differences.  \n<b>R1:<\/b> Thank you for this comment, as you mentioned the paucity has been identified in HFNO vs NIV. This is an important point to mention as this is currently a signal that HFNO is non-inferior to NIV in managing mild to moderate acute type 2 respiratory failure but the evidence base is poor and important clinical outcomes need to be robustly investigated.  \n<b>C2:<\/b> The conclusions drawn are appropriate and importantly, mention is made of the benefits of NIV which provide a rationale for further study including a trial of NIV vs HFNO.  \n<b>R2:<\/b> We agree with the rational comment you had given. Further studies are required to thoroughly evaluate the clinical significance between the treatment groups.  We once again thank the reviewer for the time and effort taken in reviewing the manuscript and providing the comments.","URL":"https:\/\/f1000research.com\/articles\/10-482\/v2#referee-comment-7114","order":1,"name":"referee-comment-7114","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.5256\/f1000research.77259.r94734, Federico Longhini, Anesthesia and Intensive Care, Department of Medical and Surgical Sciences, Magna Gr\u00e6cia University, Catanzaro, Italy, 20 Sep 2021, version 2, indexed","URL":"https:\/\/f1000research.com\/articles\/10-482\/v2#referee-response-94734","order":2,"name":"referee-response-94734","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"The author(s) declared that no grants were involved in supporting this work","order":3,"name":"grant-information","label":"Grant Information"},{"value":"This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.","order":0,"name":"copyright-info","label":"Copyright"}]}}