Chest
Original ResearchCRITICAL CARE MEDICINEPrognostic Value of Different Dead Space Indices in Mechanically Ventilated Patients With Acute Lung Injury and ARDS
Section snippets
Materials and Methods
We prospectively studied 36 mechanically ventilated patients with ALI who had been admitted to the ICU of the Hospital of Sabadell (Sabadell, Spain) [22 patients] and the Hospital of Cattinara, Trieste (Trieste, Italy) [14 patients]. The protocol was approved by the ethics committees at both institutions, and informed consent was waived because of the observational nature of the study. ALI was defined as a Murray lung injury score of ≥113 and a Pao2/fraction of inspired oxygen (Fio2) ratio of <
Results
We included 36 patients, 12 female and 24 male, with a mean age of 66 ± 15.2 years. No patients died within the first 48 h. Patients coming from the two ICUs differed in mean age (Sabadell Hospital, 61.3 ± 16.5 years; Trieste Hospital, 73.4 ± 9.4 years; p < 0.05). The clinical variables studied (Tables 1, 2) and the mortality rate were similar in the Sabadell and Trieste Hospitals (41% and 36%, respectively; difference was not significant). Consequently, the data were analyzed as if from a
Discussion
In ARDS patients, pioneering studies18 have shown that physiologic dead space and its evolution in the first days of the disease were associated with death. Only in the last decade have Vdphys/Vt measurements regained the attention of researchers. Nuckton et al2 published the most successful study suggesting that high Vdphys/Vt is independently associated with increased risk of death in ARDS patients. The disadvantage of this method is the need for ventilator adjustments to obtain dead space
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2022, The Lancet Respiratory MedicineCitation Excerpt :ARDS characterised by diffuse consolidations on CT differs from ARDS with focal consolidations on CT in terms of baseline respiratory mechanics and response to positive end-expiratory pressure (PEEP),13,14 as well as biological markers of pulmonary epithelial injury such as RAGE (receptor for advanced glycation end-products), which is expressed with higher levels in the plasma in patients with diffuse radiographic opacities.15 Other sources of heterogeneity in ARDS that are reflected in clinical outcomes and, in some cases, in biomarker profiles include physiological derangements such as the degree of hypoxaemia, shunt fraction, and dead space;16,17 timing of onset;18–20 and trajectory of resolution.21 Two distinct biological phenotypes of ARDS, termed hyperinflammatory and hypoinflammatory, have been consistently identified through latent class analysis22 across five randomised clinical trials (RCTs), two observational cohorts, and in a paediatric RCT (figure 1).23–28
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2016, Chinese Journal of Traumatology - English EditionCitation Excerpt :The prediction equation constructed by Frankenfield DC et al7 for dead space fraction has been proved to be capable of avoiding the abovementioned disturbances. In fact, most pioneering studies have found that the dead space fraction can reliably predict the threshold values for prognosis (i.e. >60%).2–4,6,12–14 However, we found that the mean Vd/Vt among survivors was volatile and consistently <0.50.
This study was supported by Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica and Instituto de Salud Carlos III Red GIRA (G03/063), Red Respira (ISCiii RTIC 03/11), and Institut Universitari Fundació Parc Taulí.
The authors have reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.