Working…
COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC: https://www.coronavirus.gov.

Get the latest research information from NIH: https://www.nih.gov/coronavirus.
ClinicalTrials.gov
ClinicalTrials.gov Menu

Is Venous to Arterial Conversion (v-TAC) of Blood Gas Reliable in Critical Ill Patients in the ICU?

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT03309423
Recruitment Status : Unknown
Verified October 2017 by Mads Lumholdt, Aalborg University.
Recruitment status was:  Recruiting
First Posted : October 13, 2017
Last Update Posted : October 13, 2017
Sponsor:
Collaborator:
North Denmark Regional Hospital
Information provided by (Responsible Party):
Mads Lumholdt, Aalborg University

Tracking Information
First Submitted Date October 4, 2017
First Posted Date October 13, 2017
Last Update Posted Date October 13, 2017
Actual Study Start Date October 9, 2017
Estimated Primary Completion Date January 30, 2018   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures
 (submitted: October 12, 2017)
  • Lin's Concordance correlation coefficient (CCC) [ Time Frame: 1. january 2018 ]
    Comparison of pH between ABG and aVBG (from peripheral venous catheter). The closer CCC is to 1 the better correlation.
  • Lin's Concordance correlation coefficient (CCC) [ Time Frame: 1. january 2018 ]
    Comparison of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter). The closer CCC is to 1 the better correlation.
  • Lin's Concordance correlation coefficient (CCC) [ Time Frame: 1. january 2018 ]
    Comparison of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter). The closer CCC is to 1 the better correlation.
  • Lin's Concordance correlation coefficient (CCC) [ Time Frame: 1. january 2018 ]
    Comparison of pH between ABG and aVBG (from central venous catheter). The closer CCC is to 1 the better correlation.
  • Lin's Concordance correlation coefficient (CCC) [ Time Frame: 1. january 2018 ]
    Comparison of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter). The closer CCC is to 1 the better correlation.
  • Lin's Concordance correlation coefficient (CCC) [ Time Frame: 1. january 2018 ]
    Comparison of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter). The closer CCC is to 1 the better correlation.
  • Bland and Altman's plot [ Time Frame: 1. january 2018 ]
    Mean difference and 95% limits-of-agreement of pH between ABG and aVBG (from peripheral venous catheter)
  • Bland and Altman's plot [ Time Frame: 1. january 2018 ]
    Mean difference and 95% limits-of-agreement of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter).
  • Bland and Altman's plot [ Time Frame: 1. january 2018 ]
    Mean difference and 95% limits-of-agreement of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter).
  • Bland and Altman's plot [ Time Frame: 1. january 2018 ]
    Mean difference and 95% limits-of-agreement of pH between ABG and aVBG (from central venous catheter).
  • Bland and Altman's plot [ Time Frame: 1. january 2018 ]
    Mean difference and 95% limits-of-agreement of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter).
  • Bland and Altman's plot [ Time Frame: 1. january 2018 ]
    Mean difference and 95% limits-of-agreement of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter).
Original Primary Outcome Measures Same as current
Change History No Changes Posted
Current Secondary Outcome Measures
 (submitted: October 12, 2017)
  • Number of patients with sepsis group. [ Time Frame: 1. january 2018 ]
    Number and percentage of patients in 'sepsis' group.
  • Number of patient with metabolic disease [ Time Frame: 1. january 2018 ]
    Number and percentage of patients in 'metabolic disease' group.
  • Number of patient with acute respiratory insufficiency [ Time Frame: 1. january 2018 ]
    Number and percentage of patients in 'respiratory disease group' group.
  • Mean number of days until pH neutrality in sepsis group [ Time Frame: 1. january 2018 ]
    Mean number of days until patients ABG pH was within the range 7.35-7.45 in 'sepsis' group.
  • Mean number of days until pH neutrality in patients with metabolic disease. [ Time Frame: 1. january 2018 ]
    Mean number of days until patients ABG pH was within the range 7.35-7.45 in 'metabolic disease' group.
  • Mean number of days until pH neutrality in patients with respiratory disease. [ Time Frame: 1. january 2018 ]
    Mean number of days until patients ABG pH was within the range 7.35-7.45 in 'respiratory disease' group.
Original Secondary Outcome Measures Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title Is Venous to Arterial Conversion (v-TAC) of Blood Gas Reliable in Critical Ill Patients in the ICU?
Official Title Utility of Mathematically Converted Venous to Arterial Blood Gas for Clinical Monitoring
Brief Summary

Objective: Arterial blood gas (ABG) is essential in the clinical assessment of potential acutely ill patients venous to arterial conversion (v-TAC), a mathematical method, has recently been developed to convert peripheral venous blood gas (VBG) values to arterialized VBG (aVBG) values. The aim of this study is to test the reliability of aVBG compared to ABG in an intensive care unit (ICU) setting.

Method: Consecutive patients admitted to the ICU with pH values <7,35 or >7,45 are included in this study. Paired ABG and aVBG samples are drawn from patients via arterial catheter, central venous catheter and/or peripheral venous catheter and compared.

Detailed Description

Arterial blood gas (ABG) analysis is essential in assessment of respiratory and metabolic status in acutely ill patients. In comparison to peripheral venous blood (PVG) sampling, the ABG sampling procedure is more painful for the patient and technically more challenging for the clinician to perform. Other drawbacks of ABG sampling include adverse events such as subcutaneous hematoma, arterial thrombosis or embolization, and pseudoaneurysms.

Peripheral venous blood gas (VBG) sampling has been suggested as an alternative to the ABG procedure. This procedure causes less patient discomfort and the sample can be analysed in combination with other venous blood tests. Studies have revealed that pH and bicarbonate have good correlation, whereas venous and arterial blood gasses (pO2 and pCO2) show low agreement.

However, a new method has been developed to calculate ABG values mathematically from peripheral venous blood by use of venous to arterial conversion (v-TAC) software (Obimedical, Denmark), supplemented with oxygen saturation measured by pulse oximetry. The principle of the method is a mathematical transformation of VBG values to arterialized values (aVBG) by simulating the transport of blood back through the tissue. Initial testing of the method in an emergency department setting showed acceptable clinical congruence between arterial and mathematically arterialized pH and pCO2 with a small difference (+/- SD) on 0.001 +/- 0.024 and 0.00 0.46 kPa, respectively. However, inaccurate values of pO2 were seen when oxygen saturation measured by pulse oximetry was above 96%, due to the flat shape of the oxygen dissociation curve (ODC).

Although most patients in the ICU have arterial catheters therefrom ABG can be drawn, applying arterial catheter is difficult or even impossible in some patients. In relation to step-down some patients get arterial catheters removed and in the event of deterioration in patients acid-base or respiratory disease aVBG could prove useful as a minimally invasive tool to assess patients status.

The aim of this study is to investigate if v-TAC is reliable and safe to use in patients with critically respiratory or metabolic disease admitted to the ICU.

Study Type Observational
Study Design Observational Model: Case-Only
Time Perspective: Prospective
Target Follow-Up Duration Not Provided
Biospecimen Not Provided
Sampling Method Probability Sample
Study Population All patients admitted to the ICU with acid-base and oxygenation parameters outside the normal reference values.
Condition
  • Respiratory Insufficiency
  • Metabolic Disease
  • Acidosis
  • Alkalosis
  • Sepsis
  • Abdomen, Acute
Intervention Diagnostic Test: venous to arterial conversion (v-TAC)
Venous to arterial conversion (v-TAC) is a software (Obimedical, Denmark), which can convert venous blood gas values to arterial blood gas values. The principle of the method is a mathematical transformation of VBG values to arterialized values (aVBG) by simulating the transport of blood back through the tissue. To facilitate this simulation the following physiologically relevant assumptions were made: 1) The peripheral extremity was well perfused; 2) change in base excess across the tissue sampling site was approximately zero; 3) the respiratory quotient (rate of CO2 production and O2 utilisation over capillaries) could not vary outside the range 0.7 and 1.0, and 4) the haemoglobin concentration was constant from artery to vein.
Study Groups/Cohorts
  • Respiratory disease
    Patients with acute respiratory insufficiency admitted to the ICU and with pH <7,35 or >7,45
    Intervention: Diagnostic Test: venous to arterial conversion (v-TAC)
  • Metabolic disease
    Patients with acute metabolic disease admitted to the ICU and with pH <7,35 or >7,45
    Intervention: Diagnostic Test: venous to arterial conversion (v-TAC)
  • Sepsis
    Patients with acute sepsis admitted to the ICU and with pH <7,35 or >7,45
    Intervention: Diagnostic Test: venous to arterial conversion (v-TAC)
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status Unknown status
Estimated Enrollment
 (submitted: October 12, 2017)
50
Original Estimated Enrollment Same as current
Estimated Study Completion Date March 30, 2018
Estimated Primary Completion Date January 30, 2018   (Final data collection date for primary outcome measure)
Eligibility Criteria

Inclusion Criteria:

  • All patients admitted to the intensive care with the following:
  • Arterial catheter for other purpose.
  • Peripheral venous catheter or central venous catheter for other purpose.

Exclusion Criteria:

  • Normal pH in arterial blood gas.
Sex/Gender
Sexes Eligible for Study: All
Ages Child, Adult, Older Adult
Accepts Healthy Volunteers No
Contacts Contact information is only displayed when the study is recruiting subjects
Listed Location Countries Denmark
Removed Location Countries  
 
Administrative Information
NCT Number NCT03309423
Other Study ID Numbers v-TAC-ICU
Has Data Monitoring Committee Yes
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
IPD Sharing Statement
Plan to Share IPD: No
Plan Description: IPD will be stored in safe government controlled data drives and paper data will be stored in a secure office. Doors to this office will be closed when investigators are not present. Sensitive IPD will not be shared with external researchers.
Responsible Party Mads Lumholdt, Aalborg University
Study Sponsor Aalborg University
Collaborators North Denmark Regional Hospital
Investigators
Study Director: Peter Leutscher Professor, Center for Clinical Research
PRS Account Aalborg University
Verification Date October 2017