The mechanism of injury describes how, with what force, and to which part of the body the patient was injured. Significant mechanisms of injury include:
- ejection from vehicle
- death in same passenger compartment
- falls greater than 20 feet (greater than 10 feet for infants and children)
- roll-over of vehicle
- high-speed vehicle collision (medium speed for infants and children)
- vehicle-pedestrian collision
- motorcycle crash (bicycle collision for infants and children)
- unresponsive or altered mental status
- penetrations of head, chest, or abdomen
- hidden injuries (seatbelts, airbags, etc.)
Some additional points to remember in determining mechanism of injury include:
- If the steering wheel is bent, it means that the driver has hit the steering wheel prior to inflation of the airbag if it has been deployed.
- An unrestrained occupant in a vehicle might hit any part of the body on any part of the vehicle, especially in a roll-over.
- Any object riding in the vehicle with the occupants may become a projectile and injure the occupants.
- A pedestrian hit by a vehicle may be dragged, compounding the injury.
- Features of the impact surface also determine the severity of the injury.
- Infants and children have more elastic bones which may result in more soft tissue and organ injury without bone deformity than adults.
Physical Examination of Trauma
Inspect and palpate each body area to identify obvious evidence of injury (DCAP-BTLS) such as:
contusions (deep bruising),
punctures, or penetrations,
tenderness to palpation,
lacerations (cuts), or
Head injury may be evident by facial bruising, unstable mandible, malocclusion, movable facial bones, and/or altered level of consciousness. Look for crepitation, or rubbing of broken bones together.
Neck injury is suspected if the mechanism for injury indicates potential for a head or neck injury, or if patient is unresponsive. Look for obvious evidence of injury. Exam for jugular vein distention and notice any stomas (surgical opening in the neck), or tracheostomy (surgical opening held with a plastic or metal tube).
Chest injury is indicated if paradoxical motion of the ribs is seen during respiration. It indicates that a section of the ribs has been broken and that the lungs may have been damaged also. Check the chest for crepitus, which indicates air under the skin and can be felt better than seen. It indicates a connection, due to injury, between the air inside the lungs and the skin overlying the chest. Use the stethoscope to evaluate the chest bilaterally at the apices, mid-clavicular area, mid-axillary area, and the bases. The posterior portion of the chest will not likely be available for examination since the patient will be supine. Almost any significant injury detectable with a stethoscope can be heard on the anterior of the chest.
The abdomen contains several organs which may be injured including the liver, spleen, stomach, pancreas, small and large intestine, kidneys, ureters, and large blood vessels (aorta and vena cava). In later stages of pregnancy, the uterus with the fetus will extend into the abdominal cavity. Distention of the abdomen may indicate injury. This may be difficult to determine in obese patients. If the patient is alert, areas of tenderness can be located upon palpation. A firm abdomen can be an indication that blood, stomach contents, or intestinal contents are present in the abdomen. Bruising and swelling may be a late developing sign of injury. Its absence is unimportant but its presence is very important. Look for it and be able to describe it. Beware of any colostomy or ileostomy bags that may be located under clothing before you cut it away.
The pelvis contains many blood vessels along with the bladder and female reproductive tract. The fetus is located within the pelvic ring during early pregnancy. If minimal evidence of injury is present, then gently compress the pelvis. Tenderness or motion may indicate a damaged ring and injury to structures inside. Pressure over the bony prominence in the lower abdomen may be a helpful test for pelvic fractures. Priapism, persistent erection of the penis, may be observed in patients who have had a spinal cord injury or other medical conditions.
In the alert patient ask for sites of pain or changes in sensation or movement. Look and feel for evidence of injury at these sites. The extremity with obvious or potential injury will need assessment of circulation, sensation, and motor function. In the unresponsive patient, rapidly look at and feel all extremities for evidence of injury. Circulation in the extremity should always be checked. If the unresponsive patient withdraws an extremity during examination, then sensation and motor function are intact to an unknown degree. If no movement occurs, motor and sensory function cannot be determined. Tenderness, angulation of the bone, crepitus (palpable), unusual movement, or movement in an unusual area are all signs of extremity injuries, the most severe of which would be a fracture. All injury should be managed as if it were severe.
The back should be examined for obvious signs of injury during the most appropriate time, which is often when the patient is log-rolled or if life threatening injury is suspected.
Baseline vital signs may be obtained en route to the hospital. It is important to obtain more exact umbers for the pulse, respiration, and blood pressure when appropriate than during the rapid initial assessment.
A detailed physical exam involves assessment of the head, neck, chest, abdomen, pelvis, extremities, and posterior of the body to detect signs and symptoms of injury. It also includes the face, ears, eyes, nose, and mouth during the head exam and may be done en route to the hospital. It generally may take more time than a rapid trauma assessment which involves a rapid assessment of primarily the head, neck, chest, abdomen, pelvis, extremities, and posterior of the body.
- Why is it important to assess the mechanism of injury for a trauma patient?
- What is different with a trauma focused history and physical examination from that of the medical?
- What does DCAP-BTLS stand for?
- What are the steps of the rapid trauma assessment?
- What type of patients are appropriate for rapid trauma assessment?
- What areas are examined in the detailed assessment that are usually not included in the rapid assessment?
- What do you look for and feel for in the detailed trauma assessment?
- How would you handle finding an unconscious man lying on the sidewalk at night and there were no witnesses to describe what happened?
- How would you handle a teenage girl who was shot in the chest and abdomen?
- How would you handle a woman who accidentally cut her finger severely while cutting food and it is bleeding profusely?