With the continuous advancement of technology in neonatal intensive care units, blood oxygen probes have become an important tool for monitoring the health status of newborns. It assesses the respiratory and circulatory system functions of infants by measuring the oxygen saturation (SpO₂) in the blood. Spo2 cable are usually placed on the palms or soles of newborns. However, due to the delicate skin and low blood flow of newborns, measurements in these areas are sometimes limited. Therefore, researchers began to explore other possible probe placement sites, including wrists and ankles.
In neonatal care, accurate oxygen saturation measurement is essential for timely detection and treatment of possible respiratory or circulatory problems. The basic principle of spo2 probe is to measure the proportion of oxygenated hemoglobin in the blood through a photoelectric sensor. Since the vascular structure and skin characteristics of newborns are different from those of adults, measurements at different locations may affect the accuracy of the results. Therefore, it is of great clinical significance to explore the feasibility and accuracy of placing probes at the wrists and ankles.
This article is based on the study by Phattraprayoon et al. in 2011. It aims to compare the blood oxygen concentration measurement results of the wrist and the palm of the same side, and the ankle and the sole of the same side in newborns. By analyzing the correlation and consistency between these different measurement sites, it is evaluated whether the wrist and ankle can be used as effective alternative measurement sites.
The study involved 150 newborns admitted to the neonatal intensive care unit. The researchers used blood oxygen probes to measure SpO₂ at the palm and ipsilateral wrist, and at the sole and ipsilateral ankle. Measurements were taken at the beginning, 30 seconds, and 1 minute. Using statistical methods such as regression analysis and Bland-Altman plots, the research team analyzed the relationship between paired blood oxygen concentration measurements and calculated the mean difference and standard deviation.
The study found that there was a high correlation between SpO₂ measurements at the palm and wrist, and similarly, the measurements at the sole and ankle showed a significant correlation. These results show that the wrist and ankle readings have good consistency with traditional palm and sole readings.
Through calculation and data analysis of the research results, the difference and accuracy of the measurement results of blood oxygen concentration at the wrist and ankle are within a reasonable range, which can meet the requirements of clinical monitoring.
In clinical monitoring, using wrists and ankles as sites for placement of blood oxygen probes has several potential advantages. First, the skin at these sites is thicker and the blood flow is relatively high, which may provide more stable readings. Second, wrists and ankles provide additional options for infants who have limitations on the palms and soles, such as skin lesions, injuries, or position restrictions. In addition, in emergency situations, quickly and accurately obtaining SpO₂ readings is critical for medical decision-making. By increasing the choice of measurement sites, medical staff can respond to various situations more flexibly.
However, the study also points to potential limitations. For example, because the wrist and ankle are more eccentric than the palm and sole, they may be affected by external factors such as temperature changes and external pressure. In addition, the choice of measurement site may need to be adjusted according to individual circumstances. For example, premature infants may require special attention due to the incomplete development of their skin and vascular system.
In conclusion, this study provides valuable data on pulse oximetry measurements at the wrist and ankle in newborns. The results showed good agreement between SpO₂ measurements at the wrist and ankle and those at the traditional palm and sole. Based on these findings, the wrist and ankle can serve as valid alternative measurement sites, especially when traditional sites are unavailable or inconvenient to measure. Future studies can further explore the applicability of these measurement sites in different clinical scenarios to optimize monitoring methods in newborn care.