Accuracy of laminated disposable pulse-oximeter sensors.
BACKGROUND
In our hospital, widespread utilization and clinical importance of arterial oxyhemoglobin saturation monitoring by pulse oximetry (SpO2) generated a growing cost-center in a time of fiscal restraint. We hypothesized that lamination of a pulse-oximeter sensor and insertion into a disposable, protective shield allowing reusability would not alter sensor response time or relative accuracy.


METHODS
Six healthy adult men volunteered to be studied during hypoxemia (induced by spontaneous ventilation of a 8-10% oxygen concentration in helium by face mask) to an SpO2 less than or equal to 70%. The SpO2 was monitored by 2 Nellcor N-200 pulse oximeters with D25II sensors and an Ohmeda 3700 pulse oximeter with the OxyTip sensors. Single desaturations, repeated twice in 5 subjects, and 2 desaturations, repeated 5 times in 1 subject, were evaluated. After the initial desaturation and recovery, 1 D25II sensor was laminated, inserted into a protective sheath, reattached and followed by repeat desaturation. SpO2 readings from each oximeter, during both desaturations sets were compared. Clinical importance was subjectively determined by comparison to published SpO2 bias data.


RESULTS
907 data sets were collected. In 447 SpO2 comparisons in 5 individuals (range 62-100%), 1 laminated sensor was 0.8 percentage points lower and one sensor was 1.3 percentage points higher (P less than 0.05) than controls compared with prelamination differences. No difference was clinically important. In individual repeated desaturations (range, 52-100%) following lamination, one sensor was 2.9 percentage points and one sensor was 2.6 percentage points higher. During repeat desaturations, differences between the OxyTip and the D25II control sensor were 1.3 percentage points lower and 1.8 percentage points higher than the initial desaturation (all p less than 0.001). Response times were not altered.


CONCLUSIONS
Lamination and protective shield applied to disposable sensors did not alter SpO2 measurements or response times to incremental reductions in SpO2 in a clinically important manner.
Russell
G B
GB
Penn State University College of Medicine, Hershey, USA.
Graybeal
J M
JM
D000328:Adult; D000704:Analysis of Variance; D003257:Consumer Product Safety; D003625:Data Collection; D004209:Disposable Equipment / Q000191:economics / Q000592:standards*; D017743:Equipment Reuse / Q000191:economics / Q000592:standards*; D006746:Hospital Bed Capacity, 500 and over; D017721:Hospital Costs; D006801:Humans; D000860:Hypoxia / Q000097:blood; D008297:Male; D010092:Oximetry / Q000191:economics / Q000295:instrumentation* / Q000592:standards; D010414:Pennsylvania; D011786:Quality Control