Comparing Non-Invasive Spectrophotometry to Hematology Analysis for Hemoglobin Measurements in Sickle Cell Disease Patients

Khaled Yassen; Nawal Omer; Fatimah Alsahaf; Fatima Al Amer; Fatimah Alhamad; Imran Alherz; Abdulaziz Bushehab; Fatma Alniniya; Maryam Alwabari

doi:10.3390/jcm12247517

Comparing Non-Invasive Spectrophotometry to Hematology Analysis for Hemoglobin Measurements in Sickle Cell Disease Patients

J Clin Med. 2023 Dec 5;12(24):7517. doi: 10.3390/jcm12247517.

Authors

Khaled Yassen¹, Nawal Omer², Fatimah Alsahaf³, Fatima Al Amer³, Fatimah Alhamad³, Imran Alherz⁴, Abdulaziz Bushehab⁵, Fatma Alniniya⁴, Maryam Alwabari³

Affiliations

¹ Anesthesia Unit, Surgery Department, College of Medicine, King Faisal University, Hofuf 31983, Al Ahsa, Saudi Arabia.
² Hereditary Blood Disease Center, Hofuf 36422, Al Ahsa, Saudi Arabia.
³ College of Medicine, King Faisal University, Hofuf 31983, Al Ahsa, Saudi Arabia.
⁴ Anesthesia Department, King Fahad Hospital, Ministry of Health, Hofuf 36441, Al Ahsa, Saudi Arabia.
⁵ Nursing Services, Hereditary Blood Disease Center, Hofuf 36422, Al Ahsa, Saudi Arabia.

Abstract

Patients with sickle cell disease (SCD) require repeated blood sampling for hemoglobin (Hb) concentration measurements. The primary aim of this study was to compare non-invasive spectrophotometric hemoglobin (SpHb, g/dL) measurements to those taken via an automated hematology analyzer (Hb, g/dL) in patients with SCD visiting outpatient clinics and to investigate the correlations and agreements between both measurement techniques. Secondarily, we aimed to identify the SpHb cut-off concentration for the diagnosis of anemia and to monitor the effects of the pleth variability index (PVI, %) and perfusion index (PI) on SpHb measurements. The results gained from the examination of one hundred and fifty-eight patients indicated that the SpHb measurements overestimated the lab Hb concentrations, with a mean (SpHb-Hb) bias of 0.82 g/dL (SD 1.29). The SpHb measurements were positively correlated with the Hb measurements (Kendall's tau correlation (τ), n = 158, τ = 0.68, p < 0.001), with an intra-class correlation (ICC) of 0.67 and a 95% CI from 0.57 to 0.74 (p = 0.000). The SpHb cut-off concentration to diagnose anemia was 11.4 and 11.7 g/dL for males and females, respectively. SpHb sensitivity was low for males and females at 64.4% and 57.1%; however, the specificity was higher at 90.9% and 75%, with positive predictive values (PPVs) of 95.6 and 85.7, respectively. No correlation existed between SpHb measurements and the PVI (%) in contrast with a moderate correlation with the PI (r = 0.049, p = 0.54, and r = 0.36, p < 0.001, respectively). The mean PI was low at 2.52 ± 1.7. In conclusion, the SpHb measurements were consistently higher than the lab Hb concentrations, with a positive correlation. The sensitivity and precision of the SpHb measurements were lower than expected. However, the SpHb specificity and its positive predictive values (PPVs) indicated that it is less likely for a patient with a positive SpHb test result for anemia to be non-anemic. These results will allow SpHb measurement to play a role in excluding the presence of anemia. In light of the low PI values determined, the SpHb measurements were challenging to take and, thus, require further technological improvements.

Keywords: hemoglobin; monitoring; non-invasive; sickle cell disease.

Grants and funding

3,474/Future Scientist Program sponsored by Abdulmonem Alrashed Humanitarian Foundation, Ministry of Education and the Dean Ship of Research (Grant 3,474), King Faisal University, Al Ahsa, Hofuf, Saudi Arabia.