Airway & Respiratory, Cardiac & Resuscitation, Patient Care

Research Review: What Current Studies Mean to EMS

Issue 11 and Volume 34.

Movement During Intubation
Turner CR, Block J, Shanks A, et al: “Motion of a cadaver model of cervical injury during endotracheal intubation with a Bullard laryngoscope or a Macintosh blade with and without in-line stabilization.”Journal of Trauma.67(1):61Ï66, 2009.

It_s the standard of care to apply in-line cervical stabilization when intubating a patient with a known or suspected cervical spine injury. Currently, there are no studies documenting the amount of cervical motion created with direct laryngoscopy. We know that in-line stabilization reduces visibility of the vocal cords and puts the intubator in an awkward position. So the outcome is often an increase in the amount of time required for intubation. But using a fiberoptic laryngoscope may help.

Following surgical weakening of C4Ï5, these authors measured the amount of movement that occurred with direct laryngoscopy and fiber-optic intubation using video fluoroscopy. All of the cadavers underwent intubation with and without in-line stabilization. Data analysis revealed very little difference in the amount of movement between the types of intubation in an unstable C4Ï5 segment. But more interestingly, in-line stabilization did not clinically decrease the amount of lower cervical spine motion.

These authors are not promoting intubation without in-line stabilization for cervical spine-injured patients. Their suggestion is that in-line stabilization be released if the intubation is taking too long. As long as the intubator uses as little force and head movement as possible, the outcome will be unchanged.

Etomidate for Trauma Patients
Warner KJ, Cuschieri J, Jurkovich GJ, et al: “Single-dose etomidate for rapid sequence intubation may impact outcome after severe injury.”Journal of Trauma.67(1):45Ï50, 2009.

Etomidate is the drug of choice for rapid sequence intubation (RSI) in the trauma patient because it causes the least amount of hypotension and works quickly. However, studies of hospitalized trauma patients reveal that even one dose of etomidate can reduce the amount of circulating cortisol for up to 12 hours. Cortisol plays an important role in protecting the body from inflammatory conditions, such as adult respiratory distress syndrome (ARDS), and reduces the ability to fight off serious infections, such as sepsis.„

In this study, 94 patients were followed during hospitalizationƒ35 received etomidate and 59 received another benzodiazepine for RSI. In the etomidate group, 40% developed ARDS, compared with 20% in the non-etomidate group. The percentage of patients developing multiple-organ failure was also found to be higher in the etomidate groupƒ46% versus 25%.

Etomidate is a good drug to use for RSI, especially for the patient who_s already hypotensive. But should we trade rapid onset and a positive hemodynamic profile for the potential complications that can arise from its use? This article might make a good subject for your next journal club.

Transport Times for Strokes
Ramanujam P, Castillo E, Patel E, et al: “Prehospital transport time intervals for acute stroke patients.”Journal of Emergency Medicine.37(1):40Ï45, 2009.

Transporting a stroke patient to the appropriate facility or forewarning a facility of a potential stroke patient can significantly reduce the time to treatment. But who_s better at identifying the stroke patientƒemergency medical dispatchers or paramedics? In this study, the paramedics failed to identify nearly half of the stroke patients they encountered and agreed with the dispatcher on only 27% of the calls.„

This study focused on the length of time units spent on scene and in transport of a potential stroke patient. In the 27% of cases in which there was agreement between the dispatcher and paramedic, the scene times were, on average, two minutes shorter and transport times four minutes shorter than cases in which the dispatcher and paramedic disagreed.„

A few minutes saved may not sound like much, but with a very short window of opportunity for administering brain-saving t-PA, it could be important. These authors encourage increased education for dispatchers, EMTs and paramedics on stroke identification as a way to close this time gap.„

Patient Estimation of Blood Loss
Strote J, Mayo M, Townes D: “ED patient estimation of blood loss.”American Journal of Emergency Medicine.27(6):709Ï711, 2009.„

Studies have shown that both EMS and hospital personnel are not very accurate at estimating blood loss. These authors wanted to find out if patients were any better at estimating blood loss on common surfaces, and they developed four scenarios that included varying amounts of simulated blood. The scenarios included 178 mL (3/4 cup) spilled on the floor; 5 mL mixed with mucous in a tissue; 119 mL (1/2 cup) spilled on a T-shirt; and 119 mL in a typical bathroom commode.

The findings reveal that patients are no better than health-care providers at estimating blood loss, but they_re no worse. The most accurate estimation was from blood on the floor (178 mL), and the least accurate was the blood/mucous in a tissue (5 mL). These results closely match the findings from health-care provider studies. Smaller amounts are harder to judge. Both health-care providers and patients consistently overestimated small amounts and underestimated large amounts.

EMS personnel often ask patients to estimate blood loss. Although no provider relies on that information to determine appropriate treatment, they often allow that number to influence their course of action. Maybe we should stop estimating blood loss altogether and stick to patient presentation and physiologic findings.JEMS