Received: 4 November 2020
Accepted: 4 March 2021
First Online: 22 March 2021
: The study was approved by the ethics committee at the Xuzhou Central Hospital and was conducted in accordance with the Protocol of Helsinki. Informed consent was signed by the relatives of the patients.
: All authors have given their consent for the manuscript to be published.
: The authors report no conflicts of interest in this work.