Misleading information from pulse oximetry and the usefulness of continuous blood gas monitoring in a post cardiac surgery patient.

We report a case where misleading readings form a pulse oximeter were compared with the results obtained from a continuous multiparameter blood gas sensor (Paratrend 7 - Biomedical Sensors UK). The continuous mode of recording was useful in determining the right clinical course for the patient and serves to show how pulse oximetry may demonstrate misleading results in low flow states.