Oxygen Saturation: Analytical Comparison for COVID (SHOCOVID)

In many patients, respiratory Sars-Cov2 infection causes arterial hypoxemia, which remains without signs of verbalized respiratory distress, up to a point. This phenomenon, called "happy" or "silent" hypoxemia, has a plural pathophysiological basis. Hypoxemia has been shown to be predictively associated with admission to the ICU. Therefore, the question of constant monitoring of oxygenation, practiced on a large scale, at home, in asymptomatic patients or contact cases, arises. A large number of portable pulse oximeter are currently freely available on the market; however, their clinical validation remains sometimes doubtful, or even absent from FDA standards. The objective of this study is to evaluate the accuracy of SpO2 values provided by portable pulse oximeter in COVID patients, in comparison with the reference method. The study will be conducted on a population of adult patients with COVID, hospitalized in the ICU, for whom gasometry sampling is already scheduled in the usual management.

The constant monitoring of saturation by the pulse oximeter, the result of three centuries of technological progress, has introduced a true revolution in medical management that now relies on this vital parameter. In many patients, Sars-Cov2 respiratory infection causes arterial hypoxemia, which remains without signs of verbalized respiratory distress, up to a certain point. This phenomenon, called "happy" or "silent" hypoxemia, has a plural pathophysiological basis. Hypoxemia has been shown to be predictively associated with admission to the ICU. Therefore, the question of constant monitoring of oxygenation, practiced on a large scale, at home, in asymptomatic patients or contact cases, arises. Despite its many advantages (non-invasive, kinetic), the pulse oximeter can be misused in several pathophysiological situations. The reference method for measuring hemoglobin oxygen saturation remains arterial gasometry. However, a large number of portable pulse oximeter are currently freely available on the market; however, their clinical validation is sometimes questionable or even absent from FDA standards. The objective of this study is to evaluate the accuracy of SpO2 values provided by portable pulse oximeter in COVID patients, in comparison with the reference method (arterial gasometry). The study will be conducted on a population of adult patients with COVID, hospitalized in the ICU, for whom gasometry sampling is already scheduled in the usual management. Daily at 6am, during the systematic monitoring, arterial gasometry will be taken (as part of routine care) by the nurse or medical staff on duty. Synchronous measurement of Sp02 given by three portable pulse oximeter (1 measurement point per device, therefore 3 measurements/patient/day for a minimum of 3 days).

Measurement of oxygen saturation by pulse oximetry once a day, at 6 a.m., for a minimum of 3 days, thanks to three pulse oximeters (1 measurement point per device/day), in parallel with a synchronous sampling, programmed as part of the usual care, of arterial gasometry.

To evaluate the accuracy of SpO2 value provided by portable pulse oximeter in COVID patients compared with the reference method.

Measurement of oxygen saturation by pulse oximetry once a day, at 6 a.m., for a minimum of 3 days, using three pulse oximeters (1 measurement point per device/day), in parallel with a synchronous, programmed arterial gasometry sampling Evaluation according to the standards of the SFBC (French Society of Clinical Biology) for the comparison of methods: minimum 40 points per apparatus, evenly distributed over the pathophysiological range of the saturations explored (9, 10): 60-100%.

Data analysis will allow to identify potential biases in the measurement of oxygen saturation in COVID patients

Inclusion Criteria: Patients hospitalized in the intensive care unit for COVID Age ≥ 18 years Patients or family/trusted person informed and not objecting to participating in the research Exclusion Criteria: Carbon monoxide poisoning Homozygous sickle cell disease Severe anemia (< 7 g/L) with associated hypoxemia Methemoglobinemia Sulfhemoglobinemia Sepsis, vasoconstrictive drugs Patients under guardianship / curators Patient under state medical aid