Accuracy of Determining Hemoglobin Level Using Occlusion Spectroscopy in Patients with Severe Gastrointestinal Bleeding

作者:Coquin Julien; Bertarrex Amandine; Dewitte Antoine; Lefevre Laurent; Joannes Boyau Olivier; Fleureau Catherine; Winnock Stephane; Leuillet Sebastien; Janvier Gerard; Ouattara Alexandre*
来源:Anesthesiology, 2013, 118(3): 640-648.
DOI:10.1097/ALN.0b013e3182833fcc

摘要

Background: In patients presenting with severe hemorrhage, the authors conducted an equivalence trial that compared noninvasive occlusion spectroscopy and the capillary blood method to determine hemoglobin level.
Methods: This prospective observational study included patients admitted to their intensive care unit for gastrointestinal bleeding. A ring-shaped sensor, connected to a NBM-200MP (OrSense r, Nes Ziona, Israel), was fitted onto the patient's thumb to intermittently measure hemoglobin (So t Hb). During the first 24 h after admission, venous hemoglobin level, considered as the reference method, was determined at the laboratory every 8 h and was compared to So t Hb and the capillary blood method. The primary endpoint was the proportion of inaccurate measurements, defined as greater than 15% difference compared with reference values or their unavailability for any technical reason.
Results: The study was scheduled to include 68 patients but was stopped prematurely after an interim analysis of 34 patients. The proportion of inaccuracies revealed that So t Hb could not be considered equivalent to the capillary blood method (47% [95% CI, 43-51] and 24% [95% CI, 2028]). Considering venous hemoglobin level as a reference method, the mean biases for So t Hb (n = 133) and the capillary blood method (n = 135) were, respectively, -0.4 +/- 2.0 and 0.8 +/- 1.2 g/dl (P < 0.05). So t Hb was associated with an increased incidence of failed transfusion. The inaccuracy of So t Hb tended to be increased in patients receiving vasopressor agents.
Conclusions: Noninvasive determination of hemoglobin level based on occlusion spectroscopy lacks accuracy in patients presenting with severe gastrointestinal bleeding and cannot be considered equivalent to the capillary-based method. This inaccuracy seems to be moderately influenced by the infusion of vasopressor agents.