An observational study in Respiratory Insufficiency, Metabolic Disease and Acidosis, sponsored by Aalborg University. Status unknown at 1 site in Denmark. Per ClinicalTrials.gov, last updated 2017-10-13.
Sponsored by Aalborg University · Observational
Among 28 studies in Respiratory Insufficiency with a site in Denmark — 2 open to participants now, 2 under way, none of them phase 3. Respiratory Insufficiency · Denmark.
Among the 28 studies in Respiratory Insufficiency with a site in Denmark, this one is one of 3 that started in 2017, is one of 9 observational ones, and was the 8th registered.
1,369 studies on the registry are indexed under Respiratory Insufficiency; 264 are open to participants now.
This study's planned enrollment of 50 is below the median of 100 across 455 observational studies indexed under Respiratory Insufficiency.
Browse Respiratory Insufficiency studies →2 of the 28 studies in Respiratory Insufficiency with a site in Denmark are open now, in 2 countries. Each count lists the studies.
Of the 178 Respiratory Insufficiency studies recruiting now, 134 (75%) set no upper age limit and 18 (10%) stop at 75 or younger; 21 take children under 18; 19 take healthy volunteers.
This study: all sexes · no healthy volunteers.
The full table on the hub →28 studies; the count open now beside each. This study's row is marked.
First in 2011; this study’s year is marked. 3 started in 2017.
Median enrollment 80 across the 19 interventional studies, 50 across the 9 observational. Of the 18 that completed or were terminated, 2 (11%) have results posted.
2 of 28 have an industry lead sponsor. The 10 most frequent:
Aalborg University is the lead sponsor of 182 studies on the registry; 31 are open to participants now.
Aalborg University has 1 study filed under Respiratory Insufficiency — fewer than ten, so there is no comparison to draw.
None of the studies under way reaches primary completion within a year.
Among the 28 studies in Respiratory Insufficiency with a site in Denmark, from their registry updates:
Nothing recorded among them since 2026-09-25.
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.
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.
All patients admitted to the ICU with acid-base and oxygenation parameters outside the normal reference values.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Patients with acute respiratory insufficiency admitted to the ICU and with pH \<7,35 or \>7,45
Diagnostic Test: venous to arterial conversion (v-TAC)
Patients with acute metabolic disease admitted to the ICU and with pH \<7,35 or \>7,45
Diagnostic Test: venous to arterial conversion (v-TAC)
Patients with acute sepsis admitted to the ICU and with pH \<7,35 or \>7,45
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.
Lin's Concordance correlation coefficient (CCC)
Comparison of pH between ABG and aVBG (from peripheral venous catheter). The closer CCC is to 1 the better correlation.
Time frame: 1. january 2018
Lin's Concordance correlation coefficient (CCC)
Comparison of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter). The closer CCC is to 1 the better correlation.
Time frame: 1. january 2018
Lin's Concordance correlation coefficient (CCC)
Comparison of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter). The closer CCC is to 1 the better correlation.
Time frame: 1. january 2018
Lin's Concordance correlation coefficient (CCC)
Comparison of pH between ABG and aVBG (from central venous catheter). The closer CCC is to 1 the better correlation.
Time frame: 1. january 2018
Lin's Concordance correlation coefficient (CCC)
Comparison of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter). The closer CCC is to 1 the better correlation.
Time frame: 1. january 2018
Lin's Concordance correlation coefficient (CCC)
Comparison of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter). The closer CCC is to 1 the better correlation.
Time frame: 1. january 2018
Bland and Altman's plot
Mean difference and 95% limits-of-agreement of pH between ABG and aVBG (from peripheral venous catheter)
Time frame: 1. january 2018
Bland and Altman's plot
Mean difference and 95% limits-of-agreement of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter).
Time frame: 1. january 2018
Bland and Altman's plot
Mean difference and 95% limits-of-agreement of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from peripheral venous catheter).
Time frame: 1. january 2018
Bland and Altman's plot
Mean difference and 95% limits-of-agreement of pH between ABG and aVBG (from central venous catheter).
Time frame: 1. january 2018
Bland and Altman's plot
Mean difference and 95% limits-of-agreement of pCO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter).
Time frame: 1. january 2018
Bland and Altman's plot
Mean difference and 95% limits-of-agreement of pO2 (Unit of Measurement: kilopascal) between ABG and aVBG (from central venous catheter).
Time frame: 1. january 2018
Number of patients with sepsis group.
Number and percentage of patients in 'sepsis' group.
Time frame: 1. january 2018
Number of patient with metabolic disease
Number and percentage of patients in 'metabolic disease' group.
Time frame: 1. january 2018
Number of patient with acute respiratory insufficiency
Number and percentage of patients in 'respiratory disease group' group.
Time frame: 1. january 2018
Mean number of days until pH neutrality in sepsis group
Mean number of days until patients ABG pH was within the range 7.35-7.45 in 'sepsis' group.
Time frame: 1. january 2018
Mean number of days until pH neutrality in patients with metabolic disease.
Mean number of days until patients ABG pH was within the range 7.35-7.45 in 'metabolic disease' group.
Time frame: 1. january 2018
Mean number of days until pH neutrality in patients with respiratory disease.
Mean number of days until patients ABG pH was within the range 7.35-7.45 in 'respiratory disease' group.
Time frame: 1. january 2018
Plan to share: No — 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.
No publications or documents are linked to this record.
Started Oct 2017 (actual). Primary completion is estimated for Jan 2018, 3 months after the start.
Of 232 non-industry observational studies under Respiratory Insufficiency, half reached primary completion within 22 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 54. This study's planned 3 months is below that.
Counting every sponsor, half of 248 studies reached it within 22 months; a quarter within 12 and three quarters within 44.
How these figures are worked out, and which studies are left out of them.
This study is status unknown, as verified in Oct 2017. You cannot join it, but the record below documents what was studied.
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