Sigh Ventilation on Postoperative Hypoxemia in Cardiac Surgery

NCT ID: NCT06248320

Last Updated: 2024-11-04

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 192 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-02-25
• Study Completion Date: 2024-08-11

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.

Detailed Description

The purpose of this single center, parallel group, randomized controlled study is to evaluate the effect of a perioperative sigh ventilation strategy on postoperative outcomes during the first 7 days following cardiac surgery. The study will include 192 adult patients undergoing scheduled on-pump cardiac surgery. The sigh ventilation approach will combine sigh ventilation and lung protective ventilation (6-8 ml/kg/pbw) from intubation to extubation. It will be compared to a conventional approach without sigh ventilation, with lung protective ventilation and positive end-expiratory pressure (PEEP) setting same as the intervention arm. The primary endpoint is the Spo2/Fio2 ratio during the initial post extubation hour. The secondary endpoints are postoperative pulmonary complications and hospital length of stay .

Conditions

Hypoxemia; Postoperative Complications; Cardiac Disease; Acute Lung Injury

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

Sigh ventilation

• 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

Group Type: EXPERIMENTAL

Sigh ventilation

Intervention Type: 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.

Conventional ventilation

\- 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

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Sigh ventilation

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.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• 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

Exclusion Criteria

• 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

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Zhongda Hospital

OTHER

Sponsor Role: lead

Responsible Party

Fengmei Guo

Director of Intensive Care Unit, Principal Investigator, Clinical Professor, Zhongda Hospital, Southeast University, China

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Fengmei Guo, PhD, MD

Role: STUDY_CHAIR

Nanjing Zhongda Hospital, Southeast University

Locations

Zhongda Hospital, Southeast University

Nanjing, Jiangsu, China

Countries

China

References

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.

Reference Type: DERIVED

PMID: 39232795 (View on PubMed)

Other Identifiers

SIGHVENT

Identifier Type: -

Identifier Source: org_study_id