{
  "abstract": "Background and Aims Diaphragmatic ultrasound has proven valuable for detecting dysfunction in critical care, but its preoperative role remains underexplored. We assessed intra-operator reproducibility and inter-individual variability of diaphragmatic excursion (DE) in patients without respiratory risk factors, exploring its potential role in preoperative risk stratification.Methods Twelve women (54±12 years, Body Mass Index 25.7±2.7 kg/m 2, Duke Activity Status Index >34 points) underwent preoperative diaphragmatic ultrasound assessment in supine position by a single operator. A curved probe (2–5 MHz) was placed in the longitudinal plane along the midclavicular line and below the costal margin. DE was measured using M-mode during quiet breathing, deep inspiration, and sniff test (rapid nasal inspiration). Each maneuver was repeated three times. Intra-observer reliability (intraclass correlation coefficient, ICC) and inter-individual variability (coefficient of variation, CV) were analyzed.Results The mean DE were 1.14 ± 0.32 cm for quiet breathing, 4.87 ± 1.41 cm for deep inspiration and 2.13 ± 0.81 cm for the sniff test. All maneuvers showed high intra-observer reproducibility (ICC>0.95) but substantial variability, particularly during sniff test (CV >30%). ( Table 1)Abstract EP197 Table 1Diaphragmatic excursion measurements and analysis Maneuver ICC (1,k) Global CV (%) Measured DE (cm)* Reference DE (cm)** Quiet breathing0.9528.11.14 ± 0.321.7 ± 0.4Deep inspiration0.9628.94.87 ± 1.414. ± 1.1Sniff test0.9738.02.13 ± 0.812.6 ± 0.6CV: coefficient of variation; DE: diaphragmatic excursion; ICC: intraclass correlation coefficient* Data are presented as mean ± SD.** Reference values from Boussuges et al. (2021) in seated position.Conclusions Diaphragmatic ultrasound demonstrates excellent intra-observer reliability (ICC >0.95), supporting its utility for serial perioperative assessments. However, significant inter-individual variability (CV >30%, especially during sniff testing) and systematically lower supine values compared to seated references suggest that tracking perioperative trends may be more clinically relevant than relying on absolute preoperative measurements. Despite these limitations, diaphragmatic ultrasound remains a valuable bedside tool for functional assessment, though standardized protocols are needed to optimize its perioperative application.",
  "authors": [
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Ana Rita Rocha"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Beatriz Xavier"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Susana Maia"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Alexandra Carneiro"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Ines Alves"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Erica Amaral"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Miguel Sá"
    },
    {
      "affiliations": [
        "Anesthesiology, Unidade Local de Saúde de Trás-os-Montes e Alto Douro, Vila Real, Portugal"
      ],
      "name": "Susana Caramelo"
    }
  ],
  "title": "EP197 Diaphragmatic ultrasound: reliability and clinical implications for preoperative evaluation",
  "uid": "a4d841c2-6e73-5163-90ae-9884e41c0881"
}