• Am. J. Respir. Crit. Care Med. · Dec 2024

    Air Hunger Far Exceeds Dyspnea Sense of Effort During Mechanical Ventilation and a Weaning Trial.

    • Amal Jubran, Franco Laghi, GrantBrydon J BBJBUniversity at Buffalo, Medicine, Buffalo, New York, United States.Bahá'í Institute for Higher Education,, Tehran, Iran (the Islamic Republic of)., and Martin J Tobin.
    • Hines VA Hospital, Pulmonary and Critical Care Medicine, Hines, Illinois, United States.
    • Am. J. Respir. Crit. Care Med. 2024 Dec 16.

    RationaleNo systematic investigation into dyspnea in patients receiving prolonged ventilation (>21 days) after recovering from critical-illness has been published.ObjectivesTo determine magnitude, nature and pathophysiological basis of dyspnea during an unassisted-breathing trial in prolonged-ventilation patients.MethodsDyspnea intensity and descriptor selection were investigated in 27 prolonged-ventilation patients during a 60-min unassisted-breathing trial. Pressure-time product (PTP), respiratory mechanics, and transcutaneous PCO2 (PtcCO2) were also measured.Measurements And Main ResultsOf 10 patients who reported dyspnea during assist-control ventilation, 9 (90.0%) selected "Not getting enough air" to characterize dyspnea. Tidal-volume setting was lower in dyspneic than non-dyspneic patients: 480.0 versus 559.4 ml (p<0.046). During the unassisted-breathing trial (n=26), patients developed increases in dyspnea (p<0.01) and PtcCO2 (p<0.01), but no change in minute ventilation. Dyspnea score was strongly linked to PtcCO2 (p<0.012) and airway resistance (p<0.013) but not respiratory work (although PTP was almost 3 times higher than normal). At 60 min into the trial, 83.3% of patients selected "Not getting enough air" on its own or in combination with "Too much effort" to describe discomfort whereas only 16.7% selected "Too much effort" on its own (p<0.001). Across the dyspnea spectrum, patients chose "Not getting enough air" overwhelmingly over other descriptor options (p<0.001).ConclusionsPatients developed increases in dyspnea and PtcCO2 but unchanged minute ventilation and work of breathing during an unassisted-breathing trial; patients selected air-hunger descriptors overwhelmingly over excessive effort; the observations support the belief that air hunger results from heightened respiratory-center stimulation combined with incapacity to increase minute ventilation.

      Pubmed     Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…