Wilderness and Rescue Medicine 8th Edition

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Wilderness and Rescue Medicine

is how the spleen is ruptured by blunt trauma. There may be no visible external injury, but the solid organs inside can be shattered.

organ rupture. In this case, the mechanism and history are reassuring. Even when kinetic energy is high from a large mass, low-velocity trauma remains localized. The patient with a foot crushed by a ship rolling against the pier was exposed to massive kinetic energy because of the size of the ship. But this is still a low-velocity injury with slow deceleration and no cavitation; the damage is limited to the foot. Problems Are Cumulative An isolated injury to an otherwise healthy and safe individual is a rare delight in emergency medicine, especially in the backcountry. Unfortunately, it is common for trauma to be complicated by mul- tisystem involvement, environmental extremes, and preexisting injury or illness. A patient who is already in compensated volume shock from dehy- dration is not in a good position to survive blood loss from a fractured femur . Mild hypothermia by itself can be cured in the field, but it vastly reduces the chance of survival for a patient in shock. Fractured bones might well be combined with skin abrasions, lacerations, and the risk of infection. Cold weather and ischemia is a setup for frostbite . The immediate traumatic event can be combined with everything that has developed before, leaving you with a long and complicated problem list. Extremes of age and chronic illness also elevate your level of concern. Elderly people are less able to compensate for volume loss due to less elastic- ity in the vascular system and reduced cardiac output. Small children lose heat much faster due to a larger surface area-to-weight ratio. Diabetics have more difficulty maintaining perfusion of the extremities. A careful history, exam, and appli- cation of the Generic to Specific Principle can alert you to greater risk or provide some degree of reassurance. Critical Systems Come First Major multi-system trauma can present a confus- ing picture. Assessment is complicated by acute stress reaction and the distractions caused by

General Principles

Thoracic and Abdominal Organs

The Solid Organs: liver, spleen, pancreas and kidneys, are prone to fracture and bleeding from high-energy blunt impact.

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Pay Attention to the History Attention to the mechanism of injury and how kinetic energy was absorbed often gives you more information than the secondary assessment does. For example, a patient who reports having the wind knocked out of them has just told you that their body absorbed enough energy fast enough to disrupt nerve function and possibly rupture internal organs. A sport climber whose fall was caught by a stretchable dynamic rope will have experienced substantially less deceleration than a rescue worker unfortunate enough to drop several meters and be stopped suddenly by a static rope . If your scene size-up or history reveals a high- velocity and rapid deceleration mechanism you have good reason to suspect serious injury, per- haps remote from the site of impact. Trauma like this is more likely to involve shattered bone, ruptured organs, traumatic brain injury, and/or cardiac contusion. A thorough exam and care- ful monitoring is prudent, regardless of the chief complaint and outward appearance. Conversely, low-velocity trauma tends not to cause injury elsewhere. It does not cause cavita- tion, and deceleration is minimal. The initial dam- age is restricted to the point energy is applied or is transferred by leverage or torque. In essence, what you see is what you get. In the patient with a complaint of knee pain following a slow twist- ing fall, you need not anticipate shock from solid