ABSTRACT
Objective To evaluate the accuracy of continuous noninvasive hemoglobin ( Hb ) monitoring in the patients undergoing cesarean section. Methods A total of 200 patients, at 36-42 weeks of gestation, aged 19-40 yr, with body mass index of 20.5-35.1 kg∕m2 , of ASA physical statusⅠorⅡ, undergoing elective cesarean section from June 2014 to October 2014 in our hospital, were enrolled. A sensor was positioned at patient′s finger and connected to the Masimo Radical?7 Pulse CO?Oximeter, a continuous noninvasive Hb measurement device. Noninvasive Hb obtained with Pulse CO?oximeter ( SpHb) was recorded. Before skin incision ( T0 ) , after delivery of the placenta ( T1 ) , after suturing the uterus ( T2 ) and at the end of operation ( T3 ) , blood samples from the radical artery were collected for determination of total Hb ( tHb) , and SpHb was also recorded. The agreement between two methods was assessed using Bland?Altman analysis. Results At T0-T3, tHb was 111±9, 103±8, 94±8 and (89±7) g∕L, respectively, and SpHb was 124 ± 9, 120 ± 12, 108 ± 9 and ( 103 ± 8 ) g∕L, respectively. Bland?Altman analysis showed that at T0-T3 , the mean difference between SpHb and tHb was 13.5, 17.1, 14.1 and 13.9 g∕L, respectively, and 95% confidence interval was 13.1-13.9, 16.5-17.7, 13.6-14.6 and 13.4-14.4 g∕L, respectively. The limit of agreement was 8.4-18.6, 9.1-25.1, 7.8-20.4 and 7.4-20.4 g∕L at T0-T3 , respectively, and the interchangeable limits of the two methods ranged between 3.5-23.5, 7.1-27.1, 4.1-24.1 and 3.9-23.9 g∕L at T0-T3 , respectively. The repeatability coefficient of tHb and SpHb was 16.5 and 15.8 g∕L, respectively. The relative error of SpHb was (4.6±1.0)%, (5.3±1.4)%, (4.9±1.2)% and (4.8±1.2)% at T0-T3, respectively. Conclusion Continuous noninvasive Hb monitoring provides good accuracy in the patients undergoing cesarean section.
