Clinical trial NCT04538339: Prediction of Arterial Lactate and Blood Gas Values Through the Analysis of Central Venous Blood
Official title: Prediction of Arterial Lactate and Blood Gas Values Through the Analysis of Central Venous Blood. A Human, Prospective, Multicenter Validation Study.
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Circulatory Failure
Keywords: Lactate
arterial blood gas
central venous blood
gazometer
Lead sponsor: Centre Hospitalier Régional d'Orléans
Sponsor class: OTHER
First posted: 2020-09-04
Enrollment: 398
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Studied patients will be adult patients admitted to intensive car unit and presenting signs of acute circulatory failure. Patients should carry arterial and central venous catheters for their medical needs and not exclusively for the purpose of the study.

Brief summary: Predicting arterial lactate and blood gas values with sufficient accuracy by simply analyzing central venous blood would be interesting in intensive care unit patients in whom the insertion of an arterial catheter or arterial punctures could be avoided. This prospective study aims at externally validating published mathematical models built to predict arterial values from central venous blood analysis.

Detailed description: Mathematical models for predicting arterial blood gas and arterial lactate have recently be published (PMID 27543529; see the citations section). The aim of the study is to externally validate these models in a multicenter (11 centres in France) cohort of intensive care unit patients suffering from acute circulatory failure. For the peru pose of the study, patients will undergo concomitent central venous/arterial blood sampling from 1 to 4 times during their intensive cafe unit stay. Clinical characteristics of the patients and central venous blood gas and lactate values will be used to predicted arterial values according to previously published formula. Predicted and actual arterial values of each variable of interest (pH, PaCO2, SaO2, lactate) will then be compared.

Eligibility criteria: Inclusion Criteria:

* age\>18 years
* patient admitted in a intensive care unit
* patient already carrying an indwelling arterial catheter and a superior vena cava central catheter
* patient presenting an acute circulatory failure defined by the presence of at least two of the following items: a) Persistent hypotension (systolic arterial blood pressure \< 90 mm Hg or mean arterial pressure \< 65 mm Hg) or need for continuous intravenous vasopressor treatment (at any dose). b) Presence of at least one of the following signs of hypoperfusionfusion :Change in mental status ; Skin mottling ; Oliguria (Urine output \<0.5 ml/kg body weight for at least one hour); Arterial lactate \> 2 mmol/l or peripheral venous lactate \> 3.2 mmol/l; ScvO2 \<70%.
* Routine medical management requires central venous blood sampling for ScvO2 measurement and arterial blood sampling for gazometry.

Exclusion Criteria:

* Opposition to participation in the study
* Impossibility to take a concomitant arterial and venous gazometric sample.
* Patient treated with ECMO (extracorporeal membrane,oxygrnation), intermittent dialysis or continuous dialysis during sampling
* Patient hospitalized without consent and/or deprived of liberty by court decision.

Primary outcomes:
measure: Percentage error rate when predicting arterial values (pH, PaCO2, SaO2 and lactate) from central venous values.
timeFrame: 15 minutes
Secondary outcomes:
measure: Bias and agreement interval between predicted and actual arterial values for each variable of interest.
timeFrame: 15 minutes
Other outcomes:
Locations:
city: Angers
country: France
facility: CHU d'ANGERS
city: Dijon
country: France
facility: CHU de DIJON
city: Garches
country: France
facility: Chu de Garches
city: Limoges
country: France
facility: Chu Limoges
city: Marseille
country: France
facility: Hopital de La Timone
city: Nantes
country: France
facility: CHU de NANTES
city: Orléans
country: France
facility: Chr D'Orleans
city: Poitiers
country: France
facility: CHRU de POITIERS
city: Strasbourg
country: France
facility: CHU de STRASBOURG
city: Versailles
country: France
facility: Ch de Versailles
Study officials:
affiliation: CHR Orléans, France
name: Toufik Kamel, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Boulain T, Garot D, Vignon P, Lascarrou JB, Benzekri-Lefevre D, Dequin PF; Clinical Research in Intensive Care and Sepsis (CRICS) Group. Predicting arterial blood gas and lactate from central venous blood analysis in critically ill patients: a multicentre, prospective, diagnostic accuracy study. Br J Anaesth. 2016 Sep;117(3):341-9. doi: 10.1093/bja/aew261.