The Masimo monitor can measure hemoglobin level noninvasively and accuratly

Blood hemoglobin concentration is a very common and essential test to assess patient well being and the need for blood transfusion. In the perioperative period this measurement is further more critical mainly due to the acute nature of blood loss and the need for an immediate response. Currently, hemoglobin concentration is determined by analyzing a blood sample. It requires venipuncture or arterial puncture (via an arterial line). Besides the patient discomfort there are additional disadvantages such as infection, dealing with blood product, delay with diagnosis, low update rate and cost. Masimo Labs is in the process of developing a noninvasive monitor to detect hemoglobin concentrations in real time. The monitor uses a probe placed on the patient finger that gives hemoglobin concentration continuously and noninvasively. Masimo Labs is using a technology that resembles the well accepted and clinically proven pulse-oxymeter.

The study will include surgical patients at the UCI Medical Center, preferably in cases that are known to involve major blood loss. For these cases, the anesthesia team places an arterial line for anesthesia purposes. The arterial line is used for continuous blood pressure measurements and blood draw for the assessment of several indices. We plan to compare the hemoglobin concentrations measured from blood samples to the Masimo Labs pulse-hemoglobin level readings.

Inclusion Criteria:

• Adult having surgery with arterial line

Exclusion Criteria:

• Upper extremities surgery
• Pregnant women
• Children

Adult patients in UCI Medical Center undergoing surgery