Comparison of times to intubate a simulated trauma patient in two positions

The nature of the trauma patient's injuries may compromise the airway and ultimately lead to death or neurological devastation. The same injuries complicate protecting the airway in these patients by preventing manipulation of the cervical spine for direct laryngoscopy. A recent study has shown that misplaced endotracheal tubes occur significantly more often in trauma patients than in medical patients.

The authors hypothesized that elevating the long spine board would reduce the amount of time required for paramedics to intubate a simulated trauma patient.

Paramedics from an urban emergency medical services division were given up to two opportunities to intubate a manikin in a type I ambulance in each of two positions in random order: supine and with the head elevated. The manikin was secured to a long spine board with three straps, a semi-rigid cervical collar, and a cervical immobilization device. An investigator maintained cervical spine alignment and provided cricoid pressure. The elevated position was accomplished by raising the head of the stretcher 27 degrees, resulting in 7 degrees of spine board elevation. Each attempt was timed. If the first attempt was unsuccessful, the times for both the first and second attempts were totaled to determine the total time required for intubation. Times for successful intubation in each position were compared with a Mann-Whitney test. First-attempt success rates for each position were compared with chi2 analysis. Multinomial regression was used to determine whether experience, paramedic height, or previous intubation success influenced intubation time in either position.

Fifty-five paramedics provided informed consent and completed the study. Average time to intubate the supine manikin was significantly longer than needed to intubate the head-elevated manikin (35.6 +/- 19.0 seconds vs 27.9 +/- 12.8 seconds, p = 0.025). The manikin was successfully intubated on the first attempt 84% in the supine position and 95% in the head-elevated position (p = 0.200). Regression analysis identified intubation position as the only significant predictor of intubation time (p = 0.007).

Modest elevation of the head of an immobilized patient appears to allow more rapid intubation. With the spine board properly secured to the stretcher, this technique potentially offers improved intubation time without additional cost or equipment.