Review Of: Byars NV, Tsuchitani SN, Erwin E, et al. Evaluation of success rate and access time for an adult sternal intraosseous device deployed in the prehospital setting. Prehosp Disaster Med. 2011;26(2):127–129.
This is a small prospective observational study of the use of the FAST-1 IO device in the City of Portsmouth, Va. The investigators of this study trained paramedics to insert the device in critically ill or cardiac arrest patients. The response variables the investigators were measuring were success rate and time to insertion of the device. The study’s results revealed a success rate of 73% and an average time to insertion of 67 seconds (which was time from opening the device to aspiration/fluid flow). The authors conclude the FAST-1 IO device is a suitable device for deployment in disaster or tactical environments.
Dr. Wesley: I believe the authors of this study are being gracious with their conclusion. Vascular access in the cardiac arrest patient is vital. Would you be comfortable with a device that has a failure rate of nearly 30%? That’s what this study showed. Failure of the device to deploy (trigger the needles into the sternum) was the predominant cause of failure to establish vascular access with the FAST-1. This failure rate has been validated in other studies as well, which begs the question as to the value of this technique.
Although this study did not compare the FAST-1 against other IO techniques, readers will wonder how these numbers compare to studies using such devices as the EZ-IO. The EZ-IO has a first-attempt success rate of about 85% and the ability to make a second attempt on the other extremity studies document an overall success rate of 90–95% with most failures occurring not because of problems with the device but with failures to locate the proper insertion landmark or use the correct size needle. I hope education can help address these reasons of failure.
I’m sure I’m going to get some nasty e-mails stating that I’m biased to the EZ-IO, but in all fairness, I have no stock in that device and am simply looking at this from a point of practicality and logic.
Medic Marshall: The doc’s right on this one. Although the authors report their findings to be in the range of other research as far as success rates (72–84% success rate); it still does nothing to comfort me in the fact that it successfully deployed only 7 out of 10 times. When you dive a little deeper and start looking at the failures (there were 11 of them), 7 of the 11 failed to deploy at all. I would call that a major complication or critical failure.
So, let us do some basic math: the device was attempted 41 times, with 30 successful insertions, which leaves us with a success rate of 73%. OK, this is not terrible, but it’s not great. Of the 41 attempts, 7 critical failures occurred, which leaves us with a critical failure rate of 17%. I don’t know about most people, but I find that to be an alarming rate, especially from a clinical quality standpoint. Furthermore, for the cost of this device and the failure rate reported in the study, I sure wouldn’t want to invest that kind of money. It would be interesting to see what data the manufacturer reports on their critical failure rates.
Now … in all fairness, should we really be using this study to determine the efficacy of the FAST-1 IO in cardiac arrest patients? I don’t think so. The study is essentially a convenience sample of cardiac arrest patients with very few opportunities to assess whether or not this device is worth implementing. So my parting thought is this: When you read and evaluate research, you should always try to dig a little deeper into the numbers. Statistics can be very misleading at times, most likely an unintentional consequence of study design or statistical analysis. So the job falls on us as readers to dig a little deeper and see what the numbers are actually saying … and what they aren’t.
Introduction: Access to the vascular system of the critically ill or injured adult patient is essential for resuscitation. Whether due to trauma or disease, vascular collapse may delay or preclude even experienced medical providers from obtaining standard IV access. Access to the highly vascular intramedullary space of long bones provides a direct link to central circulation.
The sternum is a thin bone easily identified by external landmarks that contains well-vascularized marrow. The intraosseous (IO) route rapidly and reliably delivers fluids, blood products and medications. Resuscitation fluids administered by IV or IO achieve similar transit times to central circulation. The FAST-l Intraosseous Infusion System is the first FDA-approved mechanical sternal IO device. The objectives of this study were to: (1) determine the success rate of FAST-1 sternal IO device deployment in the prehospital setting; (2) compare the time of successful sternal IO device placement to published data regarding time to IV access; and (3) describe immediate complications of sternal IO use.
All paramedics in the city of Portsmouth, Va., were trained to correctly deploy the FAST-1 sternal IO device during a mandatory education session with the study investigators. The study subjects were critically ill or injured adult patients in cardiac arrest who were treated by paramedics during a one-year period. When a patient was identified as meeting study criteria, the paramedic initiated standard protocols; the FAST-1 sternal IO was substituted for the peripheral IV to establish vascular access. Time to deployment was measured, and successful placement was defined as insertion of the needle, with subsequent aspiration and fluid flow without infiltration.
Over the one-year period, paramedics attempted 41 FAST-1 insertions in the prehospital setting. Thirty (73%) of these were placed successfully. The mean time to successful placement was 67 seconds for 28 attempts; three of the 31 insertions didn’t have times recorded by the paramedic. Paramedics listed the problems with FAST-1 insertion, including: (1) difficulty with adhesive after device placement (3 events); (2) failure of needles to retract and operator had to pull the device out of the skin (2 events); and (3) slow flow (1 event). Emergency department physicians noted two events of minor bleeding around the site of device placement.
This is the first study to prospectively evaluate the prehospital use of the FAST-1 sternal IO as a first-line device to obtain vascular access in the critically ill or injured patient. The FAST-1 sternal IO device can be a valuable tool in the paramedic arsenal for the treatment of the critically ill or injured patient. The device may be of particular interest to specialty disaster teams that deploy in austere environments.