717 IO line placement attempts were performed to 685 patients from January 1, 2011 to December 31, 2016 by the State Emergency Medical Service of Latvia (SEMS) ambulance crews - 683 times with Bone Injection Gun, B.I.G. (Waismed Ltd.) and 34 times with EZ-IO (Vidacare / Arrow).  Age of patients varied from 19 days to 97 years (average 54.0 years, SD 25.3).  In 61 cases IO access was established to children, including 22 infants.  In most cases (42.5%, n=291) the patients had cardiac arrest, while 26.9% (n=184) of patients had hemodynamic instability and 30.6% (n=210) had other condition requiring vascular access during transportation to hospital. 22.6% (n=155) of patients had trauma, while 77.4% (n=530) of patients had non-trauma related condition.  Most IO insertions were performed by physicians - 63.2% (n=453), while in 36.8% (n=264) of cases IO access was performed by doctor’s assistant. Compared to physician’s managed teams, doctor’s assistants teams had better results in establishing of IO access (OR=1.31; p=0.1). Overall 81.9% success rate was achieved by physicians and 85.6% - by doctor’s assistants.  Successful IO insertion on the first attempt was achieved in 85.6% (n=614) cases.  In 14.4% (n=103) cases IO access was not established due to different reasons - bone but not marrow entered, failure to remove the trocar needle after insertion, inability to identify the insertion site correctly and improper needle length in obese patients.  16 unsuccessful IO line insertions were observed in children, including 8 infants.   Needle dislodgment was observed in 17 cases after initially successful IO access, thus diminishing overall IO line success rate to 83.3%.  First attempt success rate for B.I.G. device only was 85,2%, including 85.9% for adults and 78.5% for children. Vast majority of unsuccessful attempts were performed with B.I.G. device. There were only 2 unsuccessful IO insertions reported with EZ-IO device, but the total number of EZ-IO insertions (n=34) was too small to make statistical analysis.

Six-year experience of intraosseous access in prehospital stage