Figure 2.

Association between post-surgical methemoglobin and clinical outcomes

CI; Confidence interval; MetHb, methemoglobin. There was statistical evidence of a non-linear association only between post-surgical methemoglobin and the additional neurological outcome of delirium; therefore, post-surgical methemoglobin was modeled as a non-linear term for this outcome. Models adjusted for age, sex, diabetes status, preoperative renal function, preoperative left ventricular function, baseline chronic pulmonary disease, planned surgery, red blood cell transfusion, and hemoglobin concentration. The x axis is presented on a log-transformed scale.