Trusting The Pulse OximeterAbstract

Pulse oximeter is very essential in monitoring the oxygenation of hemoglobin in a patient. It normally involves putting a sensor on a patient’s finger tip or even earlobe. It measurers the absorbance of blood passing through the arteries and this is done at different wavelengths. The purpose of this essay is to study and complete a Mini Clini by summarizing it and finding out the reasons why Methylene blue dye is used as an immediate treatment.

Trusting the Pulse OximeterMethylene blue is used as an immediate treatment in the Mini Clini because it reacts with red blood cells to form a compound known as leukomethylene blue which reduces oxidized hemoglobin by converting the ferric ion in oxidized hemoglobin back to its oxygen carrying state; the ferrous ion state. This increases the oxygen carrying capacity of blood while drastically reducing the carbon monoxide levels in blood. Moreover, it has been shown to increase PaO2 levels and reduce the difference in PaO2 levels between the alveoli and the artery by reducing the levels of cyclic GMP.

Summary

Problem: An intubated thirty two week gestation infant suffering from moderate Respiratory

Distress has a pulse oximeter reading of SpO2 of ninety eight percent. The patient is on a

therapy known as continuous positive airway pressure. ABG level analysis revealed

PaO2 values of three twenty five millimeters of mercury and methemoglobin values of

thirty eight percent. The endotracheal tube irritation was reduced by administering the

Hurricane spray

Device description and Use: The pulse oximeter is a trivial non invasive potable device that

gives the values of pulse rate and arterial oxygen saturation by using the spectro-

photometric principle. It is normally placed on the foot of a newborn

Solution: The pulse oximeter readings are prone to external interferences especially from the

light and motion artifacts. Moreover, poor positioning of the pulse oximeter on the

newborn’s foot can result in inaccurate readings. This can be assessed and corrected by

correlating the clinical symptoms with the pulse oximetric values. Respiratory distress

is associated with reduced blood oxygen carrying capacity. Therefore, we would expect

the pulse oximeter values to highlight this by giving lower values of SpO2 and PaO2.

Additionally, a rise in methemoglobin level is inversely proportional to the PaO2 levels

in blood therefore with the increased methemoglobin levels, we expect the PaO2 to be

decreased.

Conclusion

This essay has focused on the pulse oximeter values which as we have seen, are prone to human and natural errors which can be corrected using proper correlation.

References

Prashant. R, Ginimuge, SD Jyothi (2010): “ Methylene Blue revisited”. Journal of

Anesthesiology and Clinical Pharmacology. Jersey Publishers Volume: 26 Issue: 4 

Page: 517-520

Severinghaus, John W.; Honda, Yoshiyuki (April 1987): “History of Blood Gas Analysis: Pulse

Oximeter” Journal of Clinical Monitoring. Sage Publishers 3 (2): 135–138.