Evaluation of a new pulse oximeter sensor.
BACKGROUND
A new forehead noninvasive oxygen saturation sensor may improve signal quality in patients with low cardiac index.


OBJECTIVE
To examine agreement between oxygen saturation values obtained by using digit-based and forehead pulse oximeters with arterial oxygen saturation in patients with low cardiac index.


METHODS
A method-comparison study was used to examine the agreement between 2 different pulse oximeters and arterial oxygen saturation in patients with low cardiac index. Readings were obtained from a finger and a forehead sensor and by analysis of a blood sample. Bias, precision, and root mean square differences were calculated for the digit and forehead sensors. Differences in bias and precision between the 2 noninvasive devices were evaluated with a t test (level of significance P<.05).


RESULTS
Nineteen patients with low cardiac index (calculated as cardiac output in liters per minute divided by body surface area in square meters; mean 1.98, SD 0.34) were studied for a total of 54 sampling periods. Mean (SD) oxygen saturations were 97% (2.4) for blood samples, 96% (3.2) for the finger sensor, and 97% (2.8) for the forehead sensor. By Bland Altman analysis, bias +/- precision was -1.16 +/- 1.62% for the digit sensor and -0.36 +/- 1.74% for the forehead sensor; root mean square differences were 1.93% and 1.70%, respectively. Bias and precision differed significantly between the 2 devices; the forehead sensor differed less from the blood sample.


CONCLUSIONS
In patients with low cardiac index, the forehead sensor was better than the digit sensor for pulse oximetry.
Fernandez
Marco
M
Saint Thomas Health Services, Nashville, TN 37202, USA. mfernand@stthomas.org
Burns
Kathy
K
Calhoun
Beverly
B
George
Saramma
S
Martin
Beverly
B
Weaver
Chris
C
D000368:Aged; D000369:Aged, 80 and over; D002303:Cardiac Output, Low / Q000097:blood*; D004867:Equipment Design; D005385:Fingers; D005546:Forehead; D006801:Humans; D008875:Middle Aged; D010092:Oximetry / Q000295:instrumentation*; D010100:Oxygen / Q000097:blood
D010100:Oxygen