Background: Certain vital dyes are known to cause pulse oximetry (Spo2) desaturation. The authors studied the effect of isosulfan blue (IB) on Spo2.
Methods: Thirty-three women, aged 34-81 yr, who were undergoing surgery for breast cancer were studied. IB, 5 ml (50 mg), was injected intraparenchymally around the tumor area by the surgeon. A pulse oximeter was used to continuously record Spo2 values up to 130 min after IB injection. Friedman repeated-measures analysis of ranks was used to analyze the baseline Spo2 and values at 5, 10, 20, 30, 40, 50, and 60 min.
Results: Spo2 values were significantly different from baseline values at 5, 10, 20, 30, 40, 50, and 60 min (P < 0.05). In a typical patient, a maximum Spo2 decrease of 3% can be anticipated 25 min after injection of IB.
Conclusions: After peritumoral administration of IB, 50 mg, a significant interference with Spo2 will occur.