Artifactual reduction in oxygen saturation readings affected by indocyanine green in ophthalmic angiography.

PURPOSE: To investigate time-dependent changes in oxygen saturation (SpO2) readings during fluorescein angiography (FA) or simultaneous fluorescein and indocyanine green angiography (F/I). STUDY DESIGN: A prospective observational study. METHODS: One hundred twenty-five consecutive patients underwent FA or F/I. After application of the exclusion criteria, 67 patients (28 underwent FA, 39 underwent F/I) were included in the study. During angiography, SpO2 was measured by using a pulse oximeter and recording each second. The arm-to-retina circulation time (ARCT) was measured on the angiography video images. Latency time was defined as the time from intravenous injection of the dye to observation of a 3% decrease in the SpO2 reading, and variation SpO2, as the difference between baseline SpO2 and the lowest SpO2 value. RESULTS: The mean variation SpO2 was - 1.0 ± 0.6 during FA, and - 6.1 ± 1.5 during F/I. Variation SpO2 was within 2% during FA and > 3% during F/I. No corresponding changes were observed in the other vital signs or subjective symptoms. The mean latency time was 33.3 ± 6.4 s. Latency time was positively correlated with the ARCT in the F/I group (rs = 0.766, P < .001). CONCLUSION: Reductions in SpO2 readings were identified during F/I, but not during FA. Our results suggest that clinicians should be mindful that reductions in SpO2 readings during F/I may be artifactually caused by indocyanine green.

Prevalence and risk factors of hepatitis B virus reactivation in patients with solid tumors with resolved HBV infection.

BACKGROUND: Reports of hepatitis B virus (HBV) reactivation in solid tumors are very limited, and their frequencies and risk factors were previously unknown. AIM: To evaluate the prevalence and risk factors of HBV reactivation in patients with solid tumors with resolved HBV infection. METHODS: All 1088 patients with solid tumors were assessed for eligibility; 251 patients had resolved HBV infection (negative for HBs antigen and positive for anti-HBc antibody and/or positive for anti-HBs antibody), and HBV-DNA was assessed for 243 of these patients in whom we analyzed the prevalence of HBV reactivation. Risk factors for HBV reactivation were exploratorily evaluated by analysis of a case-control study. RESULTS: The prevalence of HBV-DNA reactivation was 2.1% (95% confidence interval [CI], 0.3-3.9%). We did not observe any exacerbation of HBV-DNA by early intervention. A low anti-HBs antibody titer (<10.0 mIU/mL) and high average daily dexamethasone dose (>1.0 mg/day) were high risk factors, with odds ratios of 5.94 (95% CI, 1.15-30.6, P = 0.03) and 8.69 (95% CI, 1.27-58.8, P = 0.02), respectively. CONCLUSION: HBV reactivation in solid tumor patients was relatively rare. Therefore, risk factors that can identify targets for HBV screening must be determined in future studies.