|Year : 2020 | Volume
| Issue : 1 | Page : 63-65
The effect of differential site of application of the pulse oximeter in critically ill children seen in a tertiary health center
Ibrahim Aliyu1, Abubakar M Shakur2, Zainab F Ibrahim3
1 Department of Paediatrics, Aminu Kano Teaching Hospital, Bayero University Kano, Kano, Kano State, Nigeria
2 Department of Paediatrics, Aminu Kano Teaching Hospital, Kano, Kano State, Nigeria
3 Department of Nursing, Aminu Kano Teaching Hospital, Kano, Kano State, Nigeria
|Date of Submission||08-Jan-2019|
|Date of Acceptance||12-Jun-2019|
|Date of Web Publication||16-Dec-2019|
Department of Paediatrics, Aminu Kano Teaching Hospital, Bayero University Kano, Kano, Kano State
Source of Support: None, Conflict of Interest: None
Introduction: Pulse oximeter is useful in the management of the critically ill child; it gives meaningful information for immediate clinical decision-making. The fingertip probe is the most common supplied probe in most hospitals, especially in resource-limited settings, and these may not fit all pediatric age groups; hence, it is not uncommon to see such probes been applied to bigger sized digits such as the toe in younger aged children. This study therefore sought to determine if there was any difference in the SpO2 readings from those varied sites. Materials and Methods: This study was cross sectional involving 100 children seen in our pediatric emergency unit. Results: There were 59 (59.0%) males and 41 (41.0%) females with male to female ratio of 1.4:1. The age ranged from 1 to 12 years with mean of 6.0 ± 3.4 years. The mean pulse oximetry between the various pairs was almost similar for all the sites; however, this observation was not statistically significant (t = 0.269, df = 70, P = 0.789). There were significant agreements between all the studied methods of comparison of SpO2. However, this was most noticeable for the right index finger and left index finger. Conclusion: This study showed that SpO2 can be measured from any digit.
Keywords: Children, fingertip probe, pulse oximeter, SpO2
|How to cite this article:|
Aliyu I, Shakur AM, Ibrahim ZF. The effect of differential site of application of the pulse oximeter in critically ill children seen in a tertiary health center. Med J DY Patil Vidyapeeth 2020;13:63-5
|How to cite this URL:|
Aliyu I, Shakur AM, Ibrahim ZF. The effect of differential site of application of the pulse oximeter in critically ill children seen in a tertiary health center. Med J DY Patil Vidyapeeth [serial online] 2020 [cited 2020 Sep 22];13:63-5. Available from: http://www.mjdrdypv.org/text.asp?2020/13/1/63/272876
| Introduction|| |
The principle of pulse oximetry is based on light emission of different wavelength from light-emitting diodes  which is either reflected or transmitted through body parts with the machine reading the difference or changes in the absorbance based on the pulsating arteries from the body part involved., Thin parts of the body such as the earlobe and fingertips are the most applicable in the transmissive mode, while more body parts such as the chest wall, forehead, and toes among others may be used for those with reflectance mode., However, the fingertip probe is the most common supplied probe in most hospitals, especially in resource-limited settings, and these may not fit all pediatric age groups; hence, it is not uncommon to see such probes been applied to bigger sized digits such as the toe in younger aged children. This study therefore sought to determine if there was any difference in the SpO2 readings from those varied sites.
| Materials and Methods|| |
This was a cross-sectional study involving 100 children seen in our pediatric emergency unit. Permission to carry out the study was obtained from the ethical committee of Aminu Kano teaching Hospital, Kano; and consent was obtained from caregivers. The inclusion criteria were all children admitted for nonrespiratory, noncardiac morbidities (such as status epilepticus, malaria, diarrhea disease, and sepsis). Children of caregivers who declined consent were excluded; similarly, individuals who were amputees and restless were excluded to avoid motion artifacts giving erroneous readings. All children enrolled for the study had pulse oximeter (NONIN Sensors 7500) readings taken from the fingers and toes concomitantly using appropriate-sized probes to determine if there was any difference in the pulse oximeter readings from both sites. The individuals' biodata, vital signs, and pulse oximeter readings were recorded in a pro forma.
All data obtained were analyzed using Statistical Package for Social Sciences (SPSS Inc., Chicago, Illinois, USA) version 16. Qualitative variables were summarized as frequencies and percentages whereas quantitative variables were summarized as means and standard deviations while the Bland–Altman plot and Student's t-test statistics were adopted to test for associations between quantitative variables, respectively; and P < 0.05 was set as statistically significant.
| Results|| |
There were 59 (59.0%) males and 41 (41.0%) females with male to female ratio of 1.4:1. The age ranged from 1 to 12 years with mean of 6.0 ± 3.4 years.
The mean pulse oximetry between the various pairs was almost similar for all the sites except for pair 3 which was between the right index and right toe; however, this observation was not statistically significant (t = 0.269, df = 70, P = 0.789); [Table 1].
The mean of the difference between applying the pulse oximeter probe and the right index and the left index was 0.1549 ± 3.75; for the right index finger and right big toe was −0.1127 ± 3.53; and for the right index and left big toe was −0.2254 ± 4.89 as shown in [Figure 1], [Figure 2], [Figure 3], respectively. There were significant agreements between all methods. However, this was most noticeable for the right index finger and left index finger as was shown by fewer outliers.
|Figure 1: The difference between the right index and the left index finger compared with the mean difference|
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|Figure 2: The difference between the right index and the right big toe compared with the mean difference|
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|Figure 3: The difference between the right index and the left big toe compared with the mean difference|
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| Discussion|| |
Pulse oximeter is a noninvasive modality of assessing the oxygen saturation of the blood and it is of immense importance in the management of the critically ill child. Although it is not a replacement for blood gas analysis, it gives relevant information for meaningful immediate clinical decision-making. The history of pulse oximeter dates back to 1935 when Matthes , developed the wavelength ear oxygen saturation meter; this have undergone refinement over the years with significant modifications through the works of Millikan, Takuo Aoyagi and Michio Kishi, and Masimo.
This study compared the various common sites of applying the pulse oximeter fingertip probe. The index finger is predominantly supplied by the deep palmar arcus formed from radial artery while the middle finger has dual supply from both ulnar and radial arteries. The right index finger served as the reference digit in this study; this conformed with other studies on the use of pulse oximeter; furthermore, Mizukoshi et al. in their study reported that 80% of their respondents would prefer the right index finger for measuring SpO2, but the middle finger had the highest perfusion index during hyperperfusion or hypoperfusion states; and their observation was statistically significant. However, Basaranoglu et al. recommended the right middle finger based on their finding of a higher SpO2; their argument was that the middle finger had dual perfusion from the ulnar and radial arteries. Therefore, it gave better correlation oxygen saturation.
Our study however showed that obtaining the SpO2 from the fingers and big toes were of same accuracy and precision; this observation was also reported by Hinkelbein et al. This observation is clinically relevant, especially in resource-constraint settings with limited availability of probe sizes; therefore, a single probe size may serve for a wide agegroup; while using the index fingers for children, the big toes could be used for younger ages. However, our finding was different from that of Hamber et al. who documented significant delays in the detection of acute hypoxemia by pulse oximetry when using the toe compared to the hands and ears. Differences in individual selection may have accounted for this disparity; measurements were taken in recumbent critically ill individuals in our study, while the individuals in Hamber et al.'s  study were healthy volunteers.
Similarly, there was also no significant differences between both fingers, unlike Basaranoglu et al. who reported higher perfusion in the dominant hand; this they attributed to possible smaller sized fingers in the nondominant hand. Hand dominance is a development achievement attained from about the age of 3 years; therefore, younger age predominance in this study may explain the observed absence of the influence of hand dominance on the SpO2.
We did not do blood gas analysis in this study; this was a limitation we acknowledge; however, SpO2 has been shown to correlate significantly with the blood gas analysis; furthermore, SpO2 gives a real-time estimation of the oxygen saturation, which is of importance for immediate clinical decision-making.
| Conclusion|| |
This study has shown that there is no remarkable difference in measuring the SpO2 from the right fingers, left fingers, or toes.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]