Bedside dynamic calculation of mechanical power: A validation study

J Crit Care. 2020 Apr:56:167-170. doi: 10.1016/j.jcrc.2019.12.027. Epub 2020 Jan 2.

Abstract

Purpose: To develop an equation to calculate the bedside dynamic mechanical power (MPdyn) for modern ventilators using the Work of Breathing ventilator (WOBv) parameter.

Materials and methods: We developed an equation based on mechanical power values, which is equal to WOBv x minute volume. To measure mechanical power with this equation forty adult patients, hospitalized with the diagnosis of Acute Respiratory Distress Syndrome and underwent invasive mechanical ventilation, were used. To be able compare our results with Gattinoni's standart mechanical power equation (MPstd) the contribution of the PEEP was included in our equation. Then results obtained from MPdyn and MPstd were compared using univariable regression and Bland-Altman analysis. This comparison was performed at different I:E ratios, PEEP levels and tidal volumes.

Results: Analysis of the results for each condition showed that MPdyn and MPstd equation correlated with R2 ≥ 0.98. Additionally, there was no statistically significant difference between MPdyn and MPstd for patient power means were 0.04 J/min (p = .42) using Bland-Altman analysis.

Conclusions: Physicians can easily calculate mechanical power by using MPdyn at the bedside of patients on volume control mode.

MeSH terms

  • Aged
  • Decision Making
  • Female
  • Humans
  • Intensive Care Units
  • Lung / physiopathology*
  • Male
  • Middle Aged
  • Positive-Pressure Respiration / methods*
  • Positive-Pressure Respiration / standards*
  • Reproducibility of Results
  • Respiration
  • Respiratory Distress Syndrome
  • Tidal Volume*
  • Turkey
  • Ventilators, Mechanical*
  • Work of Breathing*