Ventilatory Strategies After Cardiopulmonary Bypass Evaluated by Electrical Impedance Tomography

The Effects of Ventilatory Strategies on Pulmonary Function After Cardiopulmonary Bypass Evaluated by Electrical Impedance Tomography in Patients Undergoing Cardiac Surgery

Pulmonary complications after cardiac surgeries are common. It is one of the most crucial concerns of cardiac surgeons and anesthesiologists. These adverse events may vary from a mild respiratory dysfunction to acute respiratory distress syndrome (ARDS). One of the most public reasons of these complications is atelectasis that would result in hypoxia and pneumonia. Any of these adverse events rises the prevalence of morbidity and mortality. The chief inducing causes for atelectasis are CPB and dropped blood perfusion and ventilation of the lungs. The ventilation arrest is related with a high frequency of retained bronchial sections, local atelectasis, decrease in arterial O2 concentrations as a effect of surge in arteriovenous shunt, declined lung compliance, pulmonary edema and hence increased risk of nosocomial infections.

Electrical Impedance Tomography (EIT) is a non-invasive, radiation-free, real time bedside imaging modality, which provide the assessment of regional gas volume and lung ventilation. EIT has been experienced in quite a lot of animal and clinical applications including optimization of mechanical ventilator strategies and recognition of respiratory adverse events. Besides, EIT has been used to recognize ideal PEEP by detection of homogenous ventilation in non-dependent and dependent lung regions. Homogeneous ventilation is key for inhibition of ventilator-induced lung injury.

Study Overview

• Status: Completed
• Conditions: Elective Cardiac Surgical Patients
• Intervention / Treatment: Other: ventilation mode setting

Detailed Description

The aim of this study is to use four different ventilatory strategies 【Group R : IMV(intermittent mandatory ventilation) Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) ； Group RP, Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) + PEEP : 6 cm H2O ；Group RI : Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) + Reverse IE ratio ventilation( I:E=1:1) ；Group RPI: Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) + PEEP : 6 cm H2O + Reverse IE ratio ventilation( I:E=1:1)】 to compare the beneficial in decreasing the incidence of post-operative pulmonary dysfunction after cardiac surgery including of the data of EIT, GAS , Lactate , PFR：PaO2/FiO2 ratio , cardiac index (CI) , BMI..etc . EIT were measured at two perioperative timepoints 1. after intubation at the onset of anesthesia with mechanical ventilation with 7ml/ kg (Predicted body weight) 2. at the end of surgery.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Taiwan
  • Neihu Dist
    • Taipei City, Neihu Dist, Taiwan, 11490
      • Department of Anesthesiology, Tri-Service General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age between 20-80 year-old
• Adult patients receiving elective cardiac surgery with hypothermic CPB

Exclusion Criteria:

• Patients were excluded if they had complicating comorbidities, such as chronic hepatic or renal insufficiency, acute cardiopulmonary failure requiring mechanical ventilation, intra-aortic balloon pump, or extracorporeal membrane oxygenation

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Group R; IMV(intermittent mandatory ventilation) Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight)	Other: ventilation mode setting; Ventilation strategies with 4 kinds of ventilator mode since weaning cardiopulmonary bypass (CPB), Four group were control EtCO2 between 35～45mmHg by adjusting respiratory rate, EIT Measurements were performed under supine position
Experimental: Group RP; Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) + PEEP : 6 cm H2O	Other: ventilation mode setting; Ventilation strategies with 4 kinds of ventilator mode since weaning cardiopulmonary bypass (CPB), Four group were control EtCO2 between 35～45mmHg by adjusting respiratory rate, EIT Measurements were performed under supine position
Experimental: Group RI; Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) + Reverse IE ratio ventilation( I:E=1:1)	Other: ventilation mode setting; Ventilation strategies with 4 kinds of ventilator mode since weaning cardiopulmonary bypass (CPB), Four group were control EtCO2 between 35～45mmHg by adjusting respiratory rate, EIT Measurements were performed under supine position
Experimental: Group RPI; Regular Ventilation with Tidal volume with 7ml/ kg (Predicted body weight) + PEEP : 6 cm H2O + Reverse IE ratio ventilation( I:E=1:1)	Other: ventilation mode setting; Ventilation strategies with 4 kinds of ventilator mode since weaning cardiopulmonary bypass (CPB), Four group were control EtCO2 between 35～45mmHg by adjusting respiratory rate, EIT Measurements were performed under supine position

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The correlation between Different ventilation mode and the relevant value of EIT	Compare the correlation between Different ventilation mode and the relevant value of EIT in the population of open heart surgery patient	since weaning cardiopulmonary bypass (CPB) to the end of surgery
The demographic characteristics and relevant value of EIT	Campare the demographic characteristics and relevant value of EIT in the population of open heart surgery patient	since weaning cardiopulmonary bypass (CPB) to the end of surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
If the different ventilation mode setting can improve clinical outcome	Identify the different ventilation mode setting in open heart surgery patient if can improve clinical care benifit.	since weaning cardiopulmonary bypass (CPB) to the end of surgery
The correlation between heart function & oxygenation and different ventilation mode	Survey the correlation between heart function & oxygenation and different ventilation mode	since weaning cardiopulmonary bypass (CPB) to the end of surgery

Collaborators and Investigators

• Sponsor: National Defense Medical Center, Taiwan

Publications and helpful links

General Publications

• Spinelli E, Mauri T, Fogagnolo A, Scaramuzzo G, Rundo A, Grieco DL, Grasselli G, Volta CA, Spadaro S. Electrical impedance tomography in perioperative medicine: careful respiratory monitoring for tailored interventions. BMC Anesthesiol. 2019 Aug 7;19(1):140. doi: 10.1186/s12871-019-0814-7. Erratum In: BMC Anesthesiol. 2019 Sep 4;19(1):172.

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2018
• Primary Completion (Actual): July 31, 2019
• Study Completion (Actual): July 31, 2019

Study Registration Dates

• First Submitted: March 21, 2021
• First Submitted That Met QC Criteria: March 23, 2021
• First Posted (Actual): March 24, 2021

Study Record Updates

• Last Update Posted (Actual): March 24, 2021
• Last Update Submitted That Met QC Criteria: March 23, 2021
• Last Verified: March 1, 2021

More Information

Terms related to this study

• Keywords: cardiac surgery; Electrical Impedance Tomography; Ventilatory strategies
• Other Study ID Numbers: Ventilatory with EIT post CPB

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No