Chest
Volume 96, Issue 2, August 1989, Pages 287-290
Journal home page for Chest

Skin Color and Ear Oximetry

https://doi.org/10.1378/chest.96.2.287Get rights and content

Measurements of arterial blood oxygen saturation from two ear oximeters were compared with 655 simultaneously drawn arterial blood samples in 187 patients grouped by skin color quantified by the Munsell color system. Technical problems including warning lights and messages with the two ear oximeters were recorded. There were significantly more technical problems in patients with the darkest skin color associated with inability to obtain a reading or warning messages indicating poor tissue penetration of the signal (18 and 15 percent vs 1 percent). When readings could be obtained, the ear oximetry readings were found to be slightly less accurate in the darker patient groups. These findings suggest that dark skin color may affect the performance and accuracy of ear oximeters, including the newer type of pulse oximeters. (Chest 1989; 96:287–90)

Section snippets

Patients

We studied prospectively 187 pulmonary patients referred to our laboratory for clinical exercise testing. A standard protocol was followed for either steady-state or incremental, maximal exercise testing for each patient. Steady-state tests involved exercise for at least four minutes at a level approximating the patient's normal daily activity level. Maximal tests employed one minute work increments to a symptom-limited maximum. Patients exercised either walking on a treadmill or seated on a

RESULTS

Of the 187 patients studied, the Ohmeda/Biox III oximeter was used for 476 rest and exercise samples in 136 patients and the Hewlett-Packard oximeter was used for 524 rest and exercise samples in 154 patients. The instruments were used simultaneously for 345 rest and exercise samples in 103 patients.

Technical problems with ear oximetry readings were noted in 10 out of 136 patients (7 percent) tested with the Ohmeda/Biox oximeter and five out of 154 patients (3 percent) with the Hewlett-Packard

DISCUSSION

The results of this study indicate potential problems with the performance of cutaneous oximeters in some individuals with dark skin color. For both the newer “pulse-type” two wave-length Ohmeda/Biox III and the older eight wave-length Hewlett-Packard 47201A ear oximeter, technical problems were observed significantly more frequently in the darkest patients.

For the Ohmeda/Biox III instrument, technical problems were observed in 18 percent of the darkest (group 4) patients vs only 5 percent of

REFERENCES (12)

  • HansenJE et al.

    Validity of ear oximetry in clinical exercise testing

    Chest

    (1987)
  • SaundersNA et al.

    Ear oximetry: accuracy and practicability in the assessment of arterial oxygenation

    Am Rev Respir Dis

    (1976)
  • ChapmanKR et al.

    The accuracy and response characteristics of a simplified ear oximeter

    Chest

    (1983)
  • RiesAL et al.

    Accuracy of two ear oximeters at rest and during exercise in pulmonary patients

    Am Rev Respir Dis

    (1985)
  • DouglasNJ et al.

    Accuracy, sensitivity to carboxyhemoglobin, and speed of response of the Hewlett-Packard 47201A ear oximeter

    Am Rev Respir Dis

    (1979)
  • TweeddalePM et al.

    Evaluation of Biox IIA ear oximeter

    Thorax

    (1985)
There are more references available in the full text version of this article.

Cited by (0)

This research was supported in part by NIH Grant No RR00827 from the Division of Research Resources for the Clinical Research Center.

Manuscript received May 19; revision accepted December 9.

View full text