Background Patients undergoing complex spine surgery present with multilevel spinal involvement, advanced age, and multiple comorbidities. Surgery is associated with significant blood loss and remarkable hemodynamic changes. The present study aimed to investigate the accuracy and trending ability of a non-invasive continuous method to monitor hemoglobin (SpHb) concentrations using a Radical-7™ Pulse CO-Oximeter in complex spine surgery. Methods Forty-nine patients who underwent complex spine surgery were enrolled in this prospective observational study. Multiple time points were established for data collection throughout the operation. Simultaneous SpHb–total hemoglobin (tHb) paired data were recorded for analyses. Linear regression analysis, Bland–Altman plot, four-quadrant plot, and Critchley polar plot were used to assess the accuracy and trending ability of the monitor. Results A total of 272 pairs of SpHb-tHb data were available and were divided into two groups based on the perfusion index (PI): PI values ≥1.0 ( n = 200) and PI values < 1.0 ( n = 72). The correction coefficients (r) between SpHb and tHb were 0.6946 and 0.6861 in the groups with PI values ≥1.0 and < 1.0, respectively ( P < 0000.1). In the ≥1.0 group, the mean bias was − 0.21 g/dL and the percentage error (PE) was 15.85%, whereas in the < 1.0 group, the mean bias was − 0.04 g/dL and the PE was 17.42%. Four-quadrant plot revealed a concordance rate of 85.11%, whereas the Critchley polar plot showed a concordance rate of 67.21%. Conclusions The present study demonstrates the acceptable accuracy of the Radical-7™ Pulse CO-Oximeter even with a low PI. However, the trending ability was limited and unsatisfactory.

ObjectivesOutcomes of sex differences in major cardiac surgery remain controversial. A comprehensive understanding of sex differences in major adult cardiac surgery could provide better knowledge of risk factors, management strategy and short-term or long-term outcomes. The present study aimed to investigate sex differences in the risks of outcomes of major cardiac surgeries and subgroup analyses of different valve types.DesignPopulation-based nationwide cohort study.SettingData were obtained from National Health Insurance Research Database (NHIRD) in Taiwan.ParticipantsA total of 66 326 adult patients (age ≥20 years; 30.3% women) who underwent a first major cardiac surgery (isolated coronary artery bypass graft (CABG), isolated valve or concomitant bypass/valve) from 2000 to 2013 were identified via Taiwan NHIRD.Main outcome measuresOutcomes of primary interest were in-hospital death and all-cause mortality during follow-up period. Propensity score matching was conducted as a secondary analysis for the sensitivity test.ResultsWomen who underwent isolated CABG tended to have greater risks of both in-hospital (OR 1.37; 95% CI 1.26 to 1.49) and late outcomes (HR 1.26; 95% CI 1.22 to 1.31). Women after concomitant CABG/valve also had a greater in-hospital (OR 1.19; 95% CI 1.01 to 1.40) and long-term mortality (HR 1.14; 95% CI 1.05 to 1.24). Women after isolated mitral valve repair have a non-favourable outcome of in-hospital mortality (OR 1.70; 95% CI 1.01 to 2.87). Women who did not receive an isolated aortic valve replacement had more favourable all-cause mortality outcome (HR 0.90; 95% CI 0.84 to 0.96). Secondary analysis in the propensity score-matching cohort demonstrated results similar to the primary analysis.ConclusionsFemale patients who underwent procedures involving CABG (with or without concurrent valvular intervention) had generally worse outcomes. However, the results of isolated valve surgery were variable on the basis of the type of intervened valve.

Introduction: The study aimed to reveal how the fraction of inspired oxygen (FIO 2 ) affected the value of mixed venous oxygen saturation (SvO 2 ) and the accuracy of Fick-equation-based cardiac output (Fick-CO). Methods: Forty two adult patients who underwent elective cardiac surgery were enrolled and randomly divided into 2 groups: FIO 2 < 0.7 or >0.85. Under stable general anesthesia, thermodilution-derived cardiac output (TD-CO), SvO 2 , venous partial pressure of oxygen, hemoglobin, arterial oxygen saturation, arterial partial pressure of oxygen, and blood pH levels were recorded before surgical incision. Results: Significant differences in FIO 2 values were observed between the 2 groups (0.56 ± 0.08 in the <70% group and 0.92 ± 0.03 in the >0.85 group; P < .001). The increasing FIO 2 values lead to increases in SvO 2 , venous partial pressure of oxygen, and arterial partial pressure of oxygen, with little effects on cardiac output and hemoglobin levels. When comparing to TD-CO, the calculated Fick-CO in both groups had moderate Pearson correlations and similar linear regression results. Although the FIO 2 <0.7 group presented a less mean bias and a smaller limits of agreement, neither group met the percentage error criteria of <30% in Bland-Altman analysis. Conclusion: Increased FIO 2 may influence the interpretation of SvO 2 and the exacerbation of Fick-CO estimation, which could affect clinical management. Trial Registration: ClinicalTrials.gov ID number: NCT04265924, retrospectively registered (Date of registration: February 9, 2020).