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

Abstract

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 ® , 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, 20-28]). 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.

Continuous Measurement of Hemoglobin

“…The author is not supported by, nor maintains any financial interest in, any commercial activity that may be associated with the topic of this article. Bruno Riou Editorial Views you reach the conclusion of Coquin et al 2 study. In the near future, we need to answer the following questions: (1) Do we need continuous hemoglobin monitoring?…”

Current Use of Noninvasive Hemoglobin Monitoring in Anesthesia

“…Determining hemoglobin using a noninvasive hemoglobin monitoring device in ICU patients with severe gastrointestinal bleeding appears inaccurate for clinical decision making [4, 32 • ]. In ICU patients admitted for gastrointestinal hemorrhage, the NBM-200MP lacked accuracy compared with cHb regardless of the measurement site [4]. When a study of the Radical-7 in a similar situation was performed, its clinical performance and accuracy were also not acceptable.…”

“…The lights in wavelength ranging from 600 to 950 nm are emitted from the ten spectrally stabilized emitters and detected within sensor, and the hemoglobin concentration can be measured by analyzing the signals at these wavelengths [7]. NBM-200MP additionally displays plethysmography and oxygen saturation of hemoglobin, based on the association of lowperfusion oximetry combined with occlusion spectroscopy [4]. Several studies of the OrSense products have been conducted, but have shown inconsistent results with a wide variation in biases.…”

“…NBM-200 is spot-check device and analyze pulse rate and hemoglobin value. It uses differential light absorption before and after blood flow obstruction in a finger using a ring-shaped finger sensor that is temporarily squeezed to over-systolic pressure [4,5]. This technology is known as occlusion spectroscopy and has been used to noninvasively measure glucose concentration.…”

“…The Rainbow technology has been revealed as inaccurate under poor perfusion conditions [4]; OrSense developed another noninvasive hemoglobin monitoring devices to overcome this limitation, the NBM-200 and NBM-200MP (OrSense, NesZiona, Israel). NBM-200 is spot-check device and analyze pulse rate and hemoglobin value.…”