Study of an Oxygen Supply and Oxygen Saturation Monitoring System for Radiation Therapy Associated with the Active Breathing Coordinator

Guanzhong Gong,Guanzhong Gong,Guanzhong Gong,Xuemei Sun,Yujie Guo,Yujie Guo,Yujie Guo,David Dagan Feng,Xiuying Wang,Yong Yin,Yong Yin,Yong Yin

doi:10.1038/s41598-018-19576-8

Abstract

In this study, we designed an oxygen supply and oxygen saturation monitoring (OSOSM) system. This OSOSM system can provide a continuous supply of oxygen and monitor the peripheral capillary oxygen saturation (SpO2) of patients who accept radiotherapy and use an active breathing coordinator (ABC). A clinical test with 27 volunteers was conducted. The volunteers were divided into two groups based on the tendency of SpO2 decline in breath-holding without the OSOSM system: group A (12 cases) showed a decline in SpO2 of less than 2%, whereas the decline in SpO2 in group B (15 cases) was greater than 2% and reached up to 6% in some cases. The SpO2 of most volunteers declined during rest. The breath-holding time of group A without the OSOSM system was significantly longer than that of group B (p < 0.05) and was extended with the OSOSM system by 26.6% and 27.85% in groups A and B, respectively. The SpO2 recovery time was reduced by 36.1%, and the total rest time was reduced by 27.6% for all volunteers using the OSOSM system. In summary, SpO2 declines during breath-holding and rest time cannot be ignored while applying an ABC. This OSOSM system offers a simple and effective way to monitor SpO2 variation and overcome SpO2 decline, thereby lengthening breath-holding time and shortening rest time.

Highlights

Dose and V20 could be reduced by more than 18% and 30%, respectively, during radiation therapy of thoracic esophageal carcinoma[9]
An oxygen supply and oxygen saturation monitoring (OSOSM) system was designed by using simple devices that can be found at every hospital
No mechanical collision risk existed among the linear accelerator gantry, table, active breathing coordinator (ABC) device and OSOSM system because the long gas-supply pipeline and signal-conducting wire were used to connect the oxygen supply tube and the electrocardiogram monitor to the patients

Summary

Introduction

Dose and V20 (i.e., the percentage of the normal lung receiving at least 20 Gy) could be reduced by more than 18% and 30%, respectively, during radiation therapy of thoracic esophageal carcinoma[9]. The patient’s body is in a temporary non-ventilation state when ABC is used Their lung function is affected, which creates uncertainty for the stability and reproducibility of the ABC application[10]. It creates additional concerns with regard to high dose per fraction radiation therapy modalities, such as stereotactic body radiation therapy (SBRT), which can reach up to 12 Gy/fraction or more among patients with lung cancer who need more time for every irradiation beam and fraction without an objective indication with monitoring indices[11]. The methodologies used to monitor human physiological changes and improve physiological functioning will help the use of ABC. It would assist radiation therapists in making objective decisions regarding the moment of beam-on and beam-off, as well as the start and stop of patient rest. The feasibility of its clinical application for decision making was studied

Methods

Results

Discussion

Conclusion