Sigh in Pressure Support Ventilation to Detect Respiratory System Compliance and Lung Recruitability

NCT07172061 | Completed DMC

• 1 other identifier: SIREC
• Study Type: interventional
• Target: 110
• Locations: 1 country
• Sites: 2

Brief Summary

The goal of this physiological study is to determine whether ventilator-delivered sigh breaths during pressure support ventilation (PSV) provide a reliable bedside index of lung recruitability and can guide PEEP optimization.The main questions it aims to answer are:

• Does respiratory system compliance measured at the end of a sigh (Crs\_sigh) differ from compliance obtained with an inspiratory hold during an assisted breath (Crs\_assisted), and can the Crs\_sigh/Crs\_assisted ratio indicate recruitability?
• Does adjusting PEEP based on the sigh-derived recruitability index improve respiratory mechanics and gas exchange compared with usual clinical PEEP settings?

Conditions

Mechanical Ventilation

Keywords

Assisted ventilation; Pressure support ventilation (PSV); PEEP; Recruitment; Sigh; Respiratory system compliance

Outcome Measures

Primary Outcomes (1)

• Sigh-to-Assisted Breath Respiratory System Compliance Ratio (Crs_sigh/Crs_assisted)

  Ratio of respiratory system compliance at the end of a ventilator-delivered sigh to compliance measured during an inspiratory hold on an assisted tidal breath. This normalized metric indexes recruitability during assisted ventilation; higher values indicate greater recruitability. The primary analysis is the within-patient change in the ratio from clinical PEEP to clinical PEEP +3 cmH₂O.

  End of each 15-minute step within a single study session (clinical PEEP; clinical PEEP +3 cmH₂O).

Secondary Outcomes (2)

• Patients with unreliable plateau pressure during assisted breaths

  Across both 15-minute steps within the single study session.

• Association between sigh-derived recruitability index and change in respiratory system compliance

  End of each 15-minute step within the single study session

Study Arms (2)

Clinical PEEP (baseline)

EXPERIMENTAL

Pressure support ventilation (PSV) at the clinical PEEP with ventilator-delivered sighs: one sustained inflation at 30 cmH₂O for 3 seconds every minute.

Other: PSV + sigh (Clinical PEEP and Clinical PEEP + 3 cmH₂O)

Clinical PEEP +3 cmH₂O

EXPERIMENTAL

Pressure support ventilation (PSV) with PEEP set 3 cmH₂O above the clinical PEEP, with ventilator-delivered sighs: one sustained inflation at 30 cmH₂O for 3 seconds every minute.

Other: PSV + sigh (Clinical PEEP and Clinical PEEP + 3 cmH₂O)

Interventions

PSV + sigh (Clinical PEEP and Clinical PEEP + 3 cmH₂O) OTHER

Each patient undergoes two sequential 15-minute steps: 1) pressure support ventilation at the clinical PEEP and 2) the same settings with PEEP increased by 3 cmH₂O. A ventilator-delivered sigh is programmed as one sustained inflation at 30 cmH₂O for 3 seconds every minute. All other ventilator parameters (trigger sensitivity, pressure support level, mandatory breath timing) remain unchanged. At the end of each step, inspiratory and expiratory holds are performed to collect respiratory mechanics and arterial blood gases; compliance during the sigh is calculated once flow is zero and airway pressure is stable.

Clinical PEEP (baseline); Clinical PEEP +3 cmH₂O

Eligibility Criteria

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

You may qualify if:

• Adults (≥18 years) receiving PSV with the ventilator's sigh function active.

You may not qualify if:

• Clinical contraindication to increasing PEEP
• Hemodynamic instability defined as SOFA cardiovascular score ≥3

Sponsors & Collaborators

• AUSL Romagna Rimini: lead
• Fondazione IRCCS San Gerardo dei Tintori: collaborator

Study Sites (2)

Ospedale Maurizio Bufalini

Cesena, Italy, 47521, Italy

Location

Fondazione IRCCS San Gerardo dei Tintori

Monza, Italy, 29000, Italy

Location

Related Publications (10)

• Shehabi Y, Chan L, Kadiman S, Alias A, Ismail WN, Tan MA, Khoo TM, Ali SB, Saman MA, Shaltut A, Tan CC, Yong CY, Bailey M; Sedation Practice in Intensive Care Evaluation (SPICE) Study Group investigators. Sedation depth and long-term mortality in mechanically ventilated critically ill adults: a prospective longitudinal multicentre cohort study. Intensive Care Med. 2013 May;39(5):910-8. doi: 10.1007/s00134-013-2830-2. Epub 2013 Jan 24.

  PMID: 23344834 BACKGROUND

• Marin-Corral J, Dot I, Boguna M, Cecchini L, Zapatero A, Gracia MP, Pascual-Guardia S, Vila C, Castellvi A, Perez-Teran P, Gea J, Masclans JR. Structural differences in the diaphragm of patients following controlled vs assisted and spontaneous mechanical ventilation. Intensive Care Med. 2019 Apr;45(4):488-500. doi: 10.1007/s00134-019-05566-5. Epub 2019 Feb 21.

  PMID: 30790029 BACKGROUND

• Bianchi I, Grassi A, Pham T, Telias I, Teggia Droghi M, Vieira F, Jonkman A, Brochard L, Bellani G. Reliability of plateau pressure during patient-triggered assisted ventilation. Analysis of a multicentre database. J Crit Care. 2022 Apr;68:96-103. doi: 10.1016/j.jcrc.2021.12.002. Epub 2021 Dec 21.

  PMID: 34952477 BACKGROUND

• Bastia L, Amendolagine L, Pozzi F, Carenini S, Cipolla C, Curto F, Bellani G, Fumagalli R, Chieregato A. Reliability of Respiratory System Compliance Calculation During Assisted Mechanical Ventilation: A Retrospective Study. Crit Care Med. 2023 Oct 1;51(10):e201-e205. doi: 10.1097/CCM.0000000000005964. Epub 2023 Jun 16.

  PMID: 37326475 BACKGROUND

• Mauri T, Grieco DL, Spinelli E, Leali M, Perez J, Chiavieri V, Rosa T, Ferrara P, Scaramuzzo G, Antonelli M, Spadaro S, Grasselli G. Personalized positive end-expiratory pressure in spontaneously breathing patients with acute respiratory distress syndrome by simultaneous electrical impedance tomography and transpulmonary pressure monitoring: a randomized crossover trial. Intensive Care Med. 2024 Dec;50(12):2125-2137. doi: 10.1007/s00134-024-07695-y. Epub 2024 Nov 11.

  PMID: 39527121 BACKGROUND

• Jonkman AH, Ranieri VM, Brochard L. Lung recruitment. Intensive Care Med. 2022 Jul;48(7):936-938. doi: 10.1007/s00134-022-06715-z. Epub 2022 May 2. No abstract available.

  PMID: 35499759 BACKGROUND

• Moraes L, Santos CL, Santos RS, Cruz FF, Saddy F, Morales MM, Capelozzi VL, Silva PL, de Abreu MG, Garcia CS, Pelosi P, Rocco PR. Effects of sigh during pressure control and pressure support ventilation in pulmonary and extrapulmonary mild acute lung injury. Crit Care. 2014 Aug 12;18(4):474. doi: 10.1186/s13054-014-0474-4.

  PMID: 25113136 BACKGROUND

• Patroniti N, Foti G, Cortinovis B, Maggioni E, Bigatello LM, Cereda M, Pesenti A. Sigh improves gas exchange and lung volume in patients with acute respiratory distress syndrome undergoing pressure support ventilation. Anesthesiology. 2002 Apr;96(4):788-94. doi: 10.1097/00000542-200204000-00004.

  PMID: 11964584 BACKGROUND

• Albert RK, Jurkovich GJ, Connett J, Helgeson ES, Keniston A, Voelker H, Lindberg S, Proper JL, Bochicchio G, Stein DM, Cain C, Tesoriero R, Brown CVR, Davis J, Napolitano L, Carver T, Cipolle M, Cardenas L, Minei J, Nirula R, Doucet J, Miller PR, Johnson J, Inaba K, Kao L. Sigh Ventilation in Patients With Trauma: The SiVent Randomized Clinical Trial. JAMA. 2023 Nov 28;330(20):1982-1990. doi: 10.1001/jama.2023.21739.

  PMID: 37877609 BACKGROUND

• Mauri T, Eronia N, Abbruzzese C, Marcolin R, Coppadoro A, Spadaro S, Patroniti N, Bellani G, Pesenti A. Effects of Sigh on Regional Lung Strain and Ventilation Heterogeneity in Acute Respiratory Failure Patients Undergoing Assisted Mechanical Ventilation. Crit Care Med. 2015 Sep;43(9):1823-31. doi: 10.1097/CCM.0000000000001083.

  PMID: 25985386 BACKGROUND

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD

Study Record Dates

• First Submitted: September 7, 2025
• First Posted: September 15, 2025
• Study Start: July 30, 2024
• Primary Completion: May 31, 2025
• Study Completion: June 30, 2025
• Last Updated: September 15, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

IT (2)