Nonin and Choice Oximeter Review - Normal Cases

Nonin and Choice oximeter reivew: This is the third in a series of articles in comparing the performance of oximeters made by Nonin and Choice. We used the four oximeters Onyx 9500, MD300C63, GO2, and MD300C1 to take measurements under eight simulated conditions. These conditions are presets in the BIOTEK Index SpO2 Simulator and simulate eight different common clinical situations.

In summary, all the oximeters performed very well and within their specifications.

BioTek Presets Conditions

The BioTek preset feature combines SpO2 levels, heart rates and signal length (blood perfusion) into 8 preset conditions, which simulate a broad range of normal and abnormal conditions. The intent is to challenge the oximeter under test with a variety of patient conditions to show operation over a complete range. The following table shows the predefined conditions.

	Pulse Rate	Saturation	Signal Strength
Normal	55	98%	5.0%
Weak Pulse	95	90%	0.65%
Bradycardia	45	88%	5.0%
Hypoxic	95	70%	2.0%
Neonate	180	90%	1.0%
Tachycardia	130	85%	1.2%
Geriatric	95	92%	2.4%
Obese	90	93%	3.0%

SpO2 Measurements

To understand these numbers, please read Understanding Pulse Oximeter Accuracy. Slight variance (3% to 5%) among the readings for a given setting is normal.

The following table shows the SpO2 measurements obtained during the tests.

	BioTek	Onyx 9500	MD300C63	GO2	MD300C1
Normal	98%	98%	98%	98%	98%
Weak Pulse	90%	90%	88%	92%	93%
Bradycardia	88%	88%	87%	89%	90%
Hypoxic	70%	70%	74%	70%	71%
Neonate	90%	90%	91%	91%	90%
Tachycardia	85%	85%	87%	87%	87%
Geriatric	92%	92%	93%	92%	93%
Obese	93%	92%	93%	92%	94%

Pulse Rate Measurements

The following table shows the pulse rate readings obtained. The readings showed little differences among them. Unless the patient has heart flutter or fibrillation, counting the number of pulses should not be difficult.

	BioTek	Onyx 9500	MD300C63	GO2	MD300C1
Normal	55	55	55	55	55
Weak Pulse	95	95	95	95	96
Bradycardia	45	45	45	45	45
Hypoxic	95	95	95	95	95
Neonate	180	180	180	180	179
Tachycardia	130	130	130	130	130
Geriatric	95	95	95	95	95
Obese	90	90	90	90	91

References

1. Paul Batchelder and Dena Raley, "Maximizing the Laboratory Setting for Testing Devices and Understanding Statistical Output in Pulse Oximeter", International Anesthesia Research Society, Vol. 105, No. 8, August 2007.