BOPRA, Brain Oxygenation during Prehospital Anesthesia, is a nationwide, investigator-driven study carried out in cooperation of FinnHEMS Research and Development Unit, university hospital districts, Lapland hospital district and several universities of applied sciences. The study explores cerebral oxygenation of patients undergoing prehospital anesthesia with a NIRS monitoring device designed especially for prehospital care.

Clinical Trials registration


Securing an adequate oxygen supply to the brain is the primary aim of almost all critically ill or injured patients treated by HEMS. Adequate oxygenation of the brain is a prerequisite for the patient’s full recovery. Many therapies for this purpose are available in a prehospital setting,

Despite the variety of treatment modalities, the monitoring of oxygenation of the brain in the prehospital setting is crude, dependent on indirect measures and based on population-based evidence. Thus, we wanted to pilot using near infrared spectroscopy (NIRS), already in use with high risk patients in in-hospital operating rooms, in the prehospital critical care setting and more precisely in HEMS.


It has been proved earlier that NIRS provides information that clearly complements current patient monitoring. It could probably better guide the treatment of patients also in prehospital care. The aim of this study is to monitor patients’ cerebral oxygenation during prehospital anesthesia and to see how brain oxygenation is associated with the their subsequent recovery. The ultimate goal is to develop patient monitoring modalities and thus improve their care.


BOPRA study receives no funding from the manufacturers. It is mainly funded by FinnHEMS Research and Development Unit and it has also received some funding from Helsinki University Hospital.


The main study was initiated in December 2019 at all six FinnHEMS bases. The data collection is scheduled to last 1-2 years, during which 700-1300 study patients will be recruited. During summer of 2019 the pilot study was completed at the HEMS bases of Vantaa and Oulu. The aim of the pilot study was to ensure the feasibility of the monitoring device in the HEMS setting and to provide data for refining the research methodology and sample size determination of the following large-scale main study. The experiences gained during the pilot study proved to be useful and based on those the main study can be carried out as planned.

The results of the study will be published in international peer-reviewed publications in 2020–2022.

NIRS monitoring device

The study will be carried out with a NIRS monitoring device measuring brain oxygenation with near-infrared technology. The new NIRS device is a very small combination corresponding roughly to the size of a match box and a mobile phone, which makes it easy to use in prehospital conditions.