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Table 1 True model values and corresponding estimates

From: Comments on the use of expiratory time constant for determinations of plateau pressure, respiratory system compliance, and total resistance

Patient Parameter or variable True value Estimated value Percentage error
A τE 0.25 s 0.25 s 0%
  Rtot 5 cm H2O × s/L 5 cm H2O × s/L 0%
  Crs 0.05 L/cm H2O 0.05 L/cm H2O 0%
  Pplt 13 cm H2O 13 cm H2O 0%
B τE 1.995 s 1.995 s 0%
  Rtot 21 cm H2O × s/L 24.6 cm H2O × s/L 17%
  Crs 0.095 L/cm H2O 0.0812 L/cm H2O −14.5%
  Pplt 9.78 cm H2O 8.00 cm H2O −18.2%
  1. A volume-controlled continuous mandatory ventilation was simulated with a constant inspiratory flow, a tidal volume of 0.65 L, a breathing frequency of 15 breaths per minute, an inspiration time of 1.3 seconds, a post-expiratory pause of 0.3 seconds, and an expiration time of 2.4 seconds. No external positive end-expiratory pressure was simulated. For each patient, 10 breathing cycles were simulated to allow the steady state to be reached. Data from the last simulated cycle were used to estimate expiratory time constant (τE), plateau pressure (Pplt), respiratory system compliance (Crs), and total resistance (Rtot).