Sigh Ventilation on Postoperative Hypoxemia in Cardiac Surgery

NCT06248320 | Completed DMC

• 1 other identifier: SIGHVENT
• Study Type: interventional
• Target: 192
• Locations: 1 country
• Sites: 1

Brief Summary

Postoperative pulmonary complications (PPCs) remain a frequent event after pump-on cardiac surgery and are mostly characterized by postoperative hypoxemia.These complications are significant contributors to prolonged intensive care unit admissions and an escalation in in-hospital mortality rates. The dual impact of general anesthesia with invasive mechanical ventilation results in ventilator-induced lung injury, while cardiac surgery introduces additional pulmonary insults. These include systemic inflammatory responses initiated by cardiopulmonary bypass and ischemic lung damage consequent to aortic cross-clamping. Contributing factors such as blood transfusions and postoperative pain further exacerbate the incidence of PPCs by increasing the permeability of the alveolar-capillary barrier and disrupting mucociliary functions, often culminating in pulmonary atelectasis. Protective ventilation strategies, inspired by acute respiratory distress syndrome (ARDS) management protocols, involve the utilization of low tidal volumes (6-8mL/kg predicted body weight). However, the uniform application of low tidal volumes, especially when combined with the multifactorial pulmonary insults inherent to cardiac surgery, can precipitate surfactant dysfunction and induce atelectasis. The role of pulmonary surfactant in maintaining alveolar stability is critical, necessitating continuous synthesis to sustain low surface tension and prevent alveolar collapse. The most potent stimulus for surfactant secretion is identified as the mechanical stretch of type II pneumocytes, typically induced by larger tidal volumes. This background sets the foundation for a research study aimed at assessing the safety and efficacy of incorporating sighs into perioperative protective ventilation. This approach is hypothesized to mitigate postoperative hypoxemia and reduce the incidence of PPCs in patients undergoing scheduled on-pump cardiac surgery.

Conditions

Hypoxemia; Postoperative Complications; Cardiac Disease; Acute Lung Injury

Keywords

Mechanical ventilation; Cardiac Surgery; Hypoxemia; Pulmonary Complications

Outcome Measures

Primary Outcomes (1)

• Time-weighted average pulse oximetry (SpO2/FiO2)

  Calculated the SpO2/FiO2 ratio every 15min during the initial postextubation hour, then averaged the SpO2/FiO2 ratios weighted by measurement interval. The comparison between arms was made through T-test.

  1 hour after endotracheal extubation

Secondary Outcomes (9)

• Proportion of respiratory failure

  first 7 days postextubation

• Severity of postoperative pulmonary complications

  first 7 days after surgery

• Invasive mechanical ventilation (IMV) days

  first 7 days after surgery

• Reintubation rate

  first 7 days after surgery

• Proportion of receiving non-invasive ventilation (NIV) or High-flow nasal cannula (HFNC) support

  first 7 days after surgery

Study Arms (2)

Sigh ventilation

EXPERIMENTAL

* Sigh breaths consisting of increasing positive end-expiratory pressure (PEEP) that produces a plateau pressure of 35 cmH2O (or 40 cmH2O in patients with BMIs \> 35). The sigh breaths will be delivered once every 6 minutes, as part of usual invasive mechanical ventilation, from intubation to extubation. * No sigh ventilation during thoracotomy * Lung protective ventilation from intubation to extubation, consisted of low tidal volume (6-8ml/kg/pbw) and positive end-expiratory pressure setting according to ARDS low PEEP-FiO2 table

Procedure: Sigh ventilation

Conventional ventilation

NO INTERVENTION

\- Lung protective ventilation from intubation to extubation, consisted of low tidal volume (6-8ml/kg/pbw) and positive end-expiratory pressure setting according to ARDS low PEEP-FiO2 table

Interventions

Sigh ventilation PROCEDURE

Sigh breaths were delivered from intubation to extubation. Intervention primarily conducted in the following three stages: 1. From intubation to surgical opening of the chest cavity; 2. From the surgical closure of the chest cavity close and continue unit the operating room exiting; 3. From Intensive Care Unit (ICU) arrival to Spontaneous breathing trial (SBT) start.

Sigh ventilation

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Elective cardiac surgery with general anesthesia
• Conventional cardiopulmonary bypass and aortic cross clamp
• Providing written informed consent by the patient himself/herself or the next of kin

You may not qualify if:

• Emergent surgery including aortic dissection, cardiac rupture and active endocarditis surgery
• Left ventricular assist device implantation
• Patients anticipated to require intraoperative support with Extracorporeal Membrane Oxygenation (ECMO) or Intra-Aortic Balloon Pump (IABP)
• Chronic pulmonary disease requiring long-term home oxygen therapy
• Receiving invasive mechanical ventilation within 7 days prior to surgery
• Preoperative shock
• Obstructive Sleep Apnea Syndrome (OSAS) requiring intermittent non-invasive ventilatort support
• Preoperative left ventricular ejection fraction\<40%
• Pulmonary arterial systolic pressure\>50 mmHg
• Redo surgery

Sponsors & Collaborators

• Zhongda Hospital: lead

Study Sites (1)

Zhongda Hospital, Southeast University

Nanjing, Jiangsu, 210009, China

Location

Related Publications (1)

• Wang Z, Cheng Q, Huang S, Sun J, Xu J, Xie J, Cao H, Guo F. Effect of perioperative sigh ventilation on postoperative hypoxemia and pulmonary complications after on-pump cardiac surgery (E-SIGHT): study protocol for a randomized controlled trial. Trials. 2024 Sep 4;25(1):585. doi: 10.1186/s13063-024-08416-y.

  PMID: 39232795 DERIVED

MeSH Terms

Conditions

Hypoxia; Postoperative Complications; Heart Diseases; Acute Lung Injury

Condition Hierarchy (Ancestors)

Signs and Symptoms, Respiratory; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Pathologic Processes; Cardiovascular Diseases; Lung Injury; Lung Diseases; Respiratory Tract Diseases

Study Officials

• Fengmei Guo, PhD, MD

  Nanjing Zhongda Hospital, Southeast University

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Director of Intensive Care Unit, Principal Investigator, Clinical Professor, Zhongda Hospital, Southeast University, China

Study Record Dates

• First Submitted: January 30, 2024
• First Posted: February 8, 2024
• Study Start: February 25, 2024
• Primary Completion: July 22, 2024
• Study Completion: August 11, 2024
• Last Updated: November 4, 2024

Record last verified: 2024-10

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)