FIO2 Influences SvO2 Interpretation and Fick-based Cardiac Output Assessment

Increased FIO2 Influences SvO2 Interpretation and Accuracy of Fick-based Cardiac Output Assessment in Cardiac Surgery Patients

In this study, the investigators sought to clarify the influence of FIO2 levels on the variables in the Fick equation and then assessed the influence of each variable on the accuracy of Fick-CO measurements in patients undergoing cardiac surgery.

Study Overview

• Status: Completed
• Conditions: Cardiac Output
• Intervention / Treatment: Other: fraction of inspired oxygen (FIO2)

Detailed Description

Patients who are aged ≥20 years, are undergoing planned elective cardiac surgery, and provided signed informed consent are included in the present study. Any patients with an intra-cardiac shunt are excluded.

The patients are randomly assigned to 2 groups: FIO2 <0.7 or FIO2 >0.85. And during the surgery, the oximeter values are kept ≥98%. Intra-operatively, FIO2, PaO2, SaO2, SvO2, PvO2, Hb, blood pH values, body temperature and TD-CO are recorded.

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

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• undergoing planned elective cardiac surgery
• agree to sign informed consent

Exclusion Criteria:

• intra-cardiac shunt

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: >0.85 FIO2 group; This group receives FIO2 >0.85 during the surgery.	Other: fraction of inspired oxygen (FIO2); The fraction of inspired oxygen (FIO2) is given accordingly (>0.85 for the >0.85 group, and <0.7 for the <0.7 group) to the patients during the surgery.
ACTIVE_COMPARATOR: <0.7 FIO2 group; This group receives FIO2 <0.7 during the surgery.	Other: fraction of inspired oxygen (FIO2); The fraction of inspired oxygen (FIO2) is given accordingly (>0.85 for the >0.85 group, and <0.7 for the <0.7 group) to the patients during the surgery.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Hemoglobin Values in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will collect hemoglobin data in each patient.	under general anesthesia but before surgical incision
The Oxygen Consumption in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will use the LaFarge equation to calculate oxygen consumption (ml/min/m^2) in each patient.	under general anesthesia but before surgical incision
The Blood PH Values in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will calculate oxygen consumption in each patient.	under general anesthesia but before surgical incision
The Body Temperatures in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will calculate oxygen consumption in each patient.	under general anesthesia but before surgical incision
The SaO2 in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will calculate oxygen consumption in each patient.	under general anesthesia but before surgical incision
The SvO2 in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will calculate oxygen consumption in each patient.	under general anesthesia but before surgical incision
The PaO2 in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will calculate oxygen consumption in each patient.	under general anesthesia but before surgical incision
The PvO2 in Different FIO2 Groups during Cardiac Surgeries	The patients were divided into two FIO2 groups (FIO2 >0.85 or <0.7) during the surgery. We will calculate oxygen consumption in each patient.	under general anesthesia but before surgical incision

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Precision of Fick-based Cardiac Output in Different FIO2 Groups during Cardiac Surgeries	After collecting the elements data included in the Fick eqaution (oxygen consumption, hemoglobin, SaO2, SvO2, PaO2, and PvO2), we can calculate the Fick-based cardiac output in each patient. And the pulmonary artery thermodilution is adopted as the standard cardiac output monitoring method. We will calculate the correlation and level of agreement between Fick-based cardiac output and pulmonary artery thermodilution in the two groups.	under general anesthesia but before surgical incision

Collaborators and Investigators

• Sponsor: Chang Gung Memorial Hospital

Publications and helpful links

General Publications

• Lin SY, Chang FC, Lin JR, Chou AH, Tsai YF, Liao CC, Tsai HI, Chen CY. Increased FIO2 influences SvO2 interpretation and accuracy of Fick-based cardiac output assessment in cardiac surgery patients: A prospective randomized study. Medicine (Baltimore). 2021 Sep 10;100(36):e27020. doi: 10.1097/MD.0000000000027020.

Study record dates

Study Major Dates

• Study Start (ACTUAL): December 1, 2015
• Primary Completion (ACTUAL): November 30, 2016
• Study Completion (ACTUAL): November 30, 2016

Study Registration Dates

• First Submitted: February 9, 2020
• First Submitted That Met QC Criteria: February 9, 2020
• First Posted (ACTUAL): February 12, 2020

Study Record Updates

• Last Update Posted (ACTUAL): February 17, 2020
• Last Update Submitted That Met QC Criteria: February 12, 2020
• Last Verified: February 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: 104-7177B

Drug and device information, study documents

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