{
  "abstract": "Introduction The ARTP had previously recommended 2 – 4 minutes for plethysmographic thermal equilibrium before measuring thoracic gas volume (TGV), although their most recent guidelines simply recommend allowing for ‘sufficient time’ for thermal equilibration (Sylvester et al. BMJORR 2020:5;7(1): e000575). Our current equipment provider recommends an equilibration period of 45 seconds – 1 minute. We sought to determine if these conflicting recommendations yielded different results.Methods This is a prospective pilot study of TGV measurement (MedGraphics Platinum Elite, Tewksbury, UK) in 7 staff members at the time of submission (with more due to be recruited). The ability of participants to perform technically acceptable and reproducible TGV manoeuvres was predetermined via biological quality control. Once the plethysmograph was sealed, participants performed TGV measurements at 45 seconds, 2 minutes, 3 minutes, and 4 minutes. A thermometer was placed inside the plethysmograph and temperature was recorded at each time point. Serial measurements of both TGV and temperature were compared using a repeated measures ANOVA test.Results Participants were 5 males and 2 females of mean age 32 (range 23 – 66), mean BMI 25.1 kg/m² (SEM 1.24) with no history of respiratory disease and previous plethysmographic lung volumes within normal limits. Temperature increased significantly over the 4-minute testing period (p < 0.0001) but there was no significant difference in TGV ( table 1).Abstract P13 Table 1A summary of TGV measurements and plethysmograph temperature across the 4 time points of the testing protocol (n = 7). Data are presented as mean and standard error (SEM). VTG did not differ significantly (p = ns) despite a significant increase in plethysmograph temperature (p < 0.0001)Conclusions Our pilot data suggest that the discordance in guidelines of thermal equilibrium time does not influence TGV measurement, at least in healthy individuals. However, our current data set is limited and would need to be extended to include patients with respiratory disease before definitive conclusions can be made.",
  "authors": [
    {
      "affiliations": [
        "University Hospitals Birmingham, Birmingham, UK"
      ],
      "name": "Sara McNamara"
    },
    {
      "affiliations": [
        "University Hospitals Birmingham, Birmingham, UK"
      ],
      "name": "James Stockley"
    },
    {
      "affiliations": [
        "University Hospitals Birmingham, Birmingham, UK"
      ],
      "name": "Brendan Cooper"
    }
  ],
  "title": "P13 Comparison of thoracic gas volume using ARTP guidelines for thermal equilibrium versus manufacturer recommendations",
  "uid": "12e93464-aca4-5f52-bd8f-9a328fc4c2b5"
}