Merlin MA, Kaplan E, Schlogl J, et al. Study of placing a second intravenous line in trauma. Prehosp Emerg Care 15(2): 208–13 Apr–Jun 2011.
The objective was to evaluate the benefit of emergency medical services providers placing a second intravenous (IV) line in the prehospital trauma setting. The hypothesis was that the placement of a second IV catheter in trauma does not result in an improvement in heart rate, blood pressure, rehospitalizaton rate or 30-day mortality. Methods—A retrospective chart review of 320 trauma patients in a one-year period was conducted at [authors’] level I trauma center. All trauma patients who had vascular access obtained prehospitally were included. Results—Patients with two IV lines received an average of 350 mL more fluid. No change in heart rate, pulse oximetry, Glasgow Coma Scale score, systolic blood pressure, rehospitalization rate or 30-day mortality was noted. These effects persisted for patients who were initially tachycardic or hypotensive. Conclusions—Redundant prehospital IV lines provided no noticeable benefit in physiologic support for trauma patients. When controlling for confounding variables, no significant outcome difference was noted, even in the hypotensive patients. The traditional approach for establishment of a secondary IV line in prehospital trauma patients should not be followed in a dogmatic fashion.
Many of our trauma protocols specify two IVs, often large-bore, for patients with injuries and known or suspected significant hemorrhage. The thought behind this is that more blood loss necessitates a greater ability to deliver volume than one IV can accomplish. This study concluded that the fluids from the second IV did not improve short-term measures (blood pressure, heart rate) or long-term outcomes (survival, death at 30 days).
The lack of short-term benefit was from the relatively small amount of fluid (350 mL) given. In urban and suburban areas, transport times are not hours, and this is a typical IV volume. More important is that there was no improvement in survival. Even if the fluids resulted in an increase in BP, it is likely there would have been no long-term benefit. The approach to the bleeding and hypotensive trauma patient has changed over the last decade. IV fluids can dilute coagulation factors in the blood, increase blood pressure to dislodge clots, and cause hypothermia. Permissive hypotension (allowing a systolic blood pressure of 60–80) may be a better resuscitation strategy. An important exception is traumatic brain injuries, where hypotension reduces cerebral blood flow and has been associated with worse outcomes.
With the lack of benefit and all of the potential complications (e.g., risk of needlestick, infection, vascular or nerve injury), starting that second IV may not be helpful. EMS systems should reexamine their trauma protocols with that in mind.
Angelo Salvucci, Jr., MD, FACEP, is medical director for the Santa Barbara County and Ventura County (CA) EMS agencies.