Comparison of Dynamic Mechanical Power Formula With Geometric Method in Pressure- and Volume-Controlled Ventilation: A Validation Study

NCT07099729 | Completed

• 1 other identifier: 2025-76
• Study Type: observational
• Target: 37
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective observational study aims to validate the dynamic mechanical power (MPdyn) formula by comparing it with the gold-standard geometric method (MPgeo) in patients with acute respiratory distress syndrome (ARDS) who are mechanically ventilated in volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) modes. Mechanical power (MP) is a composite parameter that integrates multiple components of ventilator-induced lung injury (VILI) and has shown strong associations with mortality in ARDS. While several formulas exist for calculating MP in VCV and PCV modes, most require inspiratory resistance, which is not readily available at the bedside. The MPdyn formula, introduced by Asar et al., allows for bedside calculation without inspiratory resistance and has shown good agreement with established formulas such as MPrs and MPLM. However, it has never been validated against the geometric method, which calculates mechanical power based on the area of the pressure-volume (P-V) loop and is considered the most accurate standard. In this single-center study, 37 deeply sedated ARDS patients were ventilated with a Servo-U ventilator using both VCV and PCV modes. For each mode, two different I:E ratios (1:2 and 1:1) were applied, and 12 screenshots of full P-V loops were captured per patient, totaling 444 images. Geometric MP (MPgeo) was calculated using Python-based image processing with OpenCV and NumPy libraries. Dynamic mechanical power (MPdyn) was computed using ventilator-recorded values of minute volume (MVe), work of breathing per liter (WOBv), and PEEP. The primary outcome was the agreement between MPdyn and MPgeo values under different ventilator modes and I:E ratios. Secondary outcomes included regression correlation (R²) and Bland-Altman analysis of bias and limits of agreement. This study seeks to determine whether MPdyn is a valid and reliable surrogate for geometric mechanical power, particularly in clinical settings where bedside calculation is needed and inspiratory resistance cannot be easily measured.

Conditions

Acute Respiratory Distress Syndrome (ARDS); Ventilated Patient in Intensive Care

Keywords

mechanical power; volume control ventilation; pressure control ventilation

Outcome Measures

Primary Outcomes (1)

• Agreement Between Dynamic Mechanical Power (MPdyn) and Geometric Mechanical Power (MPgeo) Across Ventilation Modes and I:E Ratios

  To assess the agreement between MPdyn (calculated using the dynamic mechanical power formula) and MPgeo (calculated from ventilator screenshots) in patients with ARDS under four different ventilation settings: VCV with I:E 1:2 VCV with I:E 1:1 PCV with I:E 1:2 PCV with I:E 1:1 Agreement will be quantified using Bland-Altman analysis and correlation coefficients.

  Between 24 and 48 hours after ICU admission

Study Arms (1)

ARDS patients group

This group includes all patients diagnosed with Acute Respiratory Distress Syndrome (ARDS) who underwent both volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) modes in a sequential and crossover manner.

Other: Volume-Controlled Ventilation (VCV) with inspiratory-to-expiratory (I:E) ratio of 1:2.; Other: Volume-Controlled Ventilation (VCV) with inspiratory-to-expiratory (I:E) ratio of 1:1.; Other: Pressure-Controlled Ventilation (PCV) with inspiratory-to-expiratory (I:E) ratio of 1:2.; Other: Pressure-Controlled Ventilation (PCV) with inspiratory-to-expiratory (I:E) ratio of 1:1.

Interventions

Volume-Controlled Ventilation (VCV) with inspiratory-to-expiratory (I:E) ratio of 1:2. OTHER

Patients received volume-controlled ventilation (VCV) with an inspiratory-to-expiratory (I:E) ratio of 1:2. Mechanical power was calculated geometrically (MPgeo) using ventilator screenshots, and results were compared with dynamic mechanical power (MPdyn) values.

ARDS patients group

Volume-Controlled Ventilation (VCV) with inspiratory-to-expiratory (I:E) ratio of 1:1. OTHER

Patients received volume-controlled ventilation (VCV) with an inspiratory-to-expiratory (I:E) ratio of 1:1. MPgeo was computed from ventilator screenshots and compared to MPdyn values to assess agreement.

ARDS patients group

Pressure-Controlled Ventilation (PCV) with inspiratory-to-expiratory (I:E) ratio of 1:2. OTHER

Patients received pressure-controlled ventilation (PCV) with an I:E ratio of 1:2. Mechanical power was measured using both geometric (MPgeo) and dynamic (MPdyn) methods for validation purposes.

ARDS patients group

Pressure-Controlled Ventilation (PCV) with inspiratory-to-expiratory (I:E) ratio of 1:1. OTHER

Patients received pressure-controlled ventilation (PCV) with an I:E ratio of 1:1. Geometric mechanical power calculations from ventilator screenshots were compared with MPdyn values for accuracy assessment.

ARDS patients group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of adult ICU patients diagnosed with ARDS and receiving mechanical ventilation (VCV or PCV mode) at a tertiary care hospital. Data will be collected between 24 and 48 hours after ICU admission.

You may qualify if:

• Age ≥ 18 years
• Diagnosis of moderate-to-severe ARDS according to the Berlin criteria
• Receiving mechanical ventilation in volume-controlled (VCV) or pressure-controlled (PCV) mode
• Stable hemodynamics during data collection
• Expected to remain under mechanical ventilation for at least 48 hours
• Written informed consent from legal representative

You may not qualify if:

• Presence of chest tube or pneumothorax
• Known neuromuscular disease affecting respiratory function
• Pregnancy
• Patients with do-not-resuscitate (DNR) or limitation-of-therapy orders
• Incomplete ventilator data or poor-quality screenshots

Sponsors & Collaborators

• Başakşehir Çam & Sakura City Hospital: lead

Study Sites (1)

Bakirkoy Sadi Konuk Research Hospital

Istanbul, Turkey (Türkiye)

Location

Related Publications (14)

• Marini JJ, Rodriguez RM, Lamb V. Bedside estimation of the inspiratory work of breathing during mechanical ventilation. Chest. 1986 Jan;89(1):56-63. doi: 10.1378/chest.89.1.56.

  PMID: 3940790 BACKGROUND

• Cabello B, Mancebo J. Work of breathing. Intensive Care Med. 2006 Sep;32(9):1311-4. doi: 10.1007/s00134-006-0278-3. Epub 2006 Jul 13. No abstract available.

  PMID: 16838150 BACKGROUND

• ARDS Definition Task Force; Ranieri VM, Rubenfeld GD, Thompson BT, Ferguson ND, Caldwell E, Fan E, Camporota L, Slutsky AS. Acute respiratory distress syndrome: the Berlin Definition. JAMA. 2012 Jun 20;307(23):2526-33. doi: 10.1001/jama.2012.5669.

  PMID: 22797452 BACKGROUND

• Acicbe O, Ozgur CY, Rahimi P, Canan E, Asar S, Cukurova Z. The effect of inspiratory rise time on mechanical power calculations in pressure control ventilation: dynamic approach. Intensive Care Med Exp. 2023 Dec 20;11(1):98. doi: 10.1186/s40635-023-00584-6.

  PMID: 38117345 BACKGROUND

• Iotti GA, Braschi A, Brunner JX, Smits T, Olivei M, Palo A, Veronesi R. Respiratory mechanics by least squares fitting in mechanically ventilated patients: applications during paralysis and during pressure support ventilation. Intensive Care Med. 1995 May;21(5):406-13. doi: 10.1007/BF01707409.

  PMID: 7665750 BACKGROUND

• Asar S, Acicbe O, Sabaz MS, Kucur Tulubas E, Hergunsel GO, Cukurova Z, Canan E, Cakar N. Simplified calculation of mechanical power for pressure controlled ventilation in Covid-19 ARDS patients. Minerva Anestesiol. 2022 Jan-Feb;88(1-2):42-50. doi: 10.23736/S0375-9393.21.15741-4.

  PMID: 35224956 BACKGROUND

• van der Meijden S, Molenaar M, Somhorst P, Schoe A. Calculating mechanical power for pressure-controlled ventilation. Intensive Care Med. 2019 Oct;45(10):1495-1497. doi: 10.1007/s00134-019-05698-8. Epub 2019 Jul 29. No abstract available.

  PMID: 31359082 BACKGROUND

• Becher T, van der Staay M, Schadler D, Frerichs I, Weiler N. Calculation of mechanical power for pressure-controlled ventilation. Intensive Care Med. 2019 Sep;45(9):1321-1323. doi: 10.1007/s00134-019-05636-8. Epub 2019 May 17. No abstract available.

  PMID: 31101961 BACKGROUND

• Chi Y, He H, Long Y. A simple method of mechanical power calculation: using mean airway pressure to replace plateau pressure. J Clin Monit Comput. 2021 Oct;35(5):1139-1147. doi: 10.1007/s10877-020-00575-y. Epub 2020 Aug 11.

  PMID: 32780353 BACKGROUND

• Giosa L, Busana M, Pasticci I, Bonifazi M, Macri MM, Romitti F, Vassalli F, Chiumello D, Quintel M, Marini JJ, Gattinoni L. Mechanical power at a glance: a simple surrogate for volume-controlled ventilation. Intensive Care Med Exp. 2019 Nov 27;7(1):61. doi: 10.1186/s40635-019-0276-8.

  PMID: 31773328 BACKGROUND

• Asar S, Acicbe O, Cukurova Z, Hergunsel GO, Canan E, Cakar N. 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.

  PMID: 31931417 BACKGROUND

• Serpa Neto A, Deliberato RO, Johnson AEW, Bos LD, Amorim P, Pereira SM, Cazati DC, Cordioli RL, Correa TD, Pollard TJ, Schettino GPP, Timenetsky KT, Celi LA, Pelosi P, Gama de Abreu M, Schultz MJ; PROVE Network Investigators. Mechanical power of ventilation is associated with mortality in critically ill patients: an analysis of patients in two observational cohorts. Intensive Care Med. 2018 Nov;44(11):1914-1922. doi: 10.1007/s00134-018-5375-6. Epub 2018 Oct 5.

  PMID: 30291378 BACKGROUND

• Gattinoni L, Tonetti T, Cressoni M, Cadringher P, Herrmann P, Moerer O, Protti A, Gotti M, Chiurazzi C, Carlesso E, Chiumello D, Quintel M. Ventilator-related causes of lung injury: the mechanical power. Intensive Care Med. 2016 Oct;42(10):1567-1575. doi: 10.1007/s00134-016-4505-2. Epub 2016 Sep 12.

  PMID: 27620287 BACKGROUND

• Trinkle CA, Broaddus RN, Sturgill JL, Waters CM, Morris PE. Simple, accurate calculation of mechanical power in pressure controlled ventilation (PCV). Intensive Care Med Exp. 2022 May 30;10(1):22. doi: 10.1186/s40635-022-00448-5.

  PMID: 35644896 BACKGROUND

MeSH Terms

Conditions

Respiratory Distress Syndrome

Condition Hierarchy (Ancestors)

Lung Diseases; Respiratory Tract Diseases; Respiration Disorders

Study Design

• Study Type: observational
• Observational Model: CASE CROSSOVER
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Specialist Doctor

Study Record Dates

• First Submitted: July 25, 2025
• First Posted: August 1, 2025
• Study Start: April 1, 2025
• Primary Completion: June 1, 2025
• Study Completion: June 1, 2025
• Last Updated: August 1, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)