The % of oxyhemoglobin of arterial blood is measured in patients under general anesthesia, why? What measure?

Question

measurenment would change?

Answer 1

The "oxygen saturation" is measured with a pulse oximeter that is non-invasive and just attaches to your finger. It tells us the percentage of your hemoglobin that is completely bound with oxygen. The device is actually a type of "sphectophotometer" if you ever studied chemistry. A previous writer is correct in saying that it basically ensures that your body is well oxygenated. It is obviously a very important monitor that is required in all anesthetics given. Before the days of measuring oxygen saturation, anesthetists had to go by such signs as the color of your lips, etc. which is not nearly as accurate. In addition, the appearance of blue lips (or cyanosis) is a very late finding and means that the oxygen levels are dangerously low. Pulse oximetry, together with other monitors has made anesthesia safer than it ever had been before.

Answer 2

Arterial Blood Gas Sampling

ABG sampling is performed to obtain accurate measures of Pao2, Paco2, and blood pH; these variables combined with the patient's temperature allow for calculation of HCO3 level (which can also be measured directly from venous blood) and Sao2. ABG sampling can also accurately measure carboxyhemoglobin and methemoglobin.

The radial artery is usually used. Because arterial puncture in rare cases leads to thrombosis and impaired perfusion of distal tissue, Allen's test is first performed to ensure adequate collateral circulation. With this maneuver, the radial and ulnar pulses are simultaneously occluded until the hand becomes pale. The ulnar pulse is then released while the pressure on the radial pulse is maintained. A blush across the entire hand within 7 sec of release of the ulnar pulse suggests adequate flow through the ulnar artery.

Under sterile conditions, a 22- to 25-gauge needle attached to a heparinized syringe is inserted just proximal to the maximal impulse of the radial arterial pulse and advanced slightly distally into the artery until pulsatile blood is returned. Systolic BP often pushes back the syringe plunger. After 3 to 5 mL of blood is collected, the needle is quickly withdrawn, and firm pressure is applied to the puncture site to facilitate hemostasis. Simultaneously, the ABG specimen is placed on ice to reduce O2 consumption and CO2 production by WBCs and is sent to the laboratory.

Answer 3

Hi. To make sure their is enough oxygen in the blood. The % of oxygen can change and the reflected light level on the finger worn probe changes