A blunt trauma, also known as a blunt force trauma or non-penetrating trauma, is a physical trauma due to a forceful impact without penetration of the body's surface. Blunt trauma stands in contrast with penetrating trauma, which occurs when an object pierces the skin, enters body tissue, and creates an open wound. Blunt trauma occurs due to direct physical trauma or impactful force to a body part. Such incidents often occur with road traffic collisions, assaults, and sports-related injuries, and are common among the elderly who experience falls.
Blunt trauma can lead to a wide range of injuries including , , abrasions, , internal or external hemorrhages, and .
Classification
Blunt abdominal trauma
Blunt abdominal trauma (BAT) represents 75% of all blunt trauma and is the most common example of this injury.
Seventy-five percent of BAT occurs in motor vehicle crashes,
in which rapid deceleration may propel the driver into the
steering wheel,
dashboard, or seatbelt,
causing
Bruise in less serious cases, or rupture of internal organs from briefly increased
intraluminal pressure in the more serious, depending on the force applied. Initially, there may be few indications that serious internal abdominal injury has occurred, making assessment more challenging and requiring a high degree of clinical suspicion.
There are two basic physical mechanisms at play with the potential of injury to intra-abdominal organs: compression and Acceleration.
Deceleration, on the other hand, causes stretching and shearing at the points where mobile contents in the abdomen, like the bowel, are anchored. This can cause tearing of the mesentery of the bowel and injury to the that travel within the mesentery. Classic examples of these mechanisms are a hepatic tear along the ligamentum teres and injuries to the renal artery.
When blunt abdominal trauma is complicated by 'internal injury,' the liver and spleen (see blunt splenic trauma) are most frequently involved, followed by the intestine.
In rare cases, this injury has been attributed to medical techniques such as the Heimlich maneuver,
Blunt abdominal trauma in sports
The supervised environment in which most sports injuries occur allows for mild deviations from the traditional trauma treatment algorithms, such as ATLS, due to the greater precision in identifying the mechanism of injury. The priority in assessing blunt trauma in sports injuries is separating contusions and musculo-tendinous injuries from injuries to solid organs and the gut. It is also crucial to recognize the potential for developing blood loss and to react accordingly. Blunt injuries to the
kidney from helmets, shoulder pads, and knees are described in American football,
association football, martial arts, and all-terrain vehicle crashes.
Blunt thoracic trauma
The term blunt thoracic trauma, or, more informally,
blunt chest injury, encompasses a variety of injuries to the
Thorax. Broadly, this also includes damage caused by direct blunt force (such as a fist or a bat in an assault), acceleration or deceleration (such as that from a rear-end automotive crash),
shear force (a combination of acceleration and deceleration),
Crush injury (such as a heavy object falling on a person), and
Blast injury (such as an
explosion of some sort). Common signs and symptoms include something as simple as
Bruise, but occasionally as complicated as hypoxia, ventilation-perfusion mismatch,
hypovolemia, and reduced
cardiac output due to the way the
Thorax organs may have been affected. Blunt thoracic trauma is not always visible from the outside and such internal injuries may not show
Medical sign or
at the time the trauma initially occurs or even until hours after. A high degree of clinical suspicion may sometimes be required to identify such injuries, a
CT scan may prove useful in such instances. Those experiencing more obvious complications from a blunt chest injury will likely undergo a focused assessment with sonography for trauma (FAST) which can reliably detect a significant amount of blood around the heart or in the lung by using a special machine that visualizes sound waves sent through the body. Only 10–15% of thoracic traumas require surgery, but they can have serious impacts on the
heart,
, and
great vessels.
The most immediate life-threatening injuries that may occur include
Pneumothorax, open pneumothorax,
hemothorax,
flail chest, cardiac tamponade, and airway obstruction/rupture.
The injuries may necessitate a procedure, most commonly the insertion of an Chest tube, or chest tube. This tube is typically installed because it helps restore a certain balance in pressures (usually due to misplaced air or surrounding blood) that are impeding the lungs' ability to inflate and thus exchange vital gases that allow the body to function.
Blunt cranial trauma
The primary clinical concern with blunt trauma to the head is damage to the brain, although other structures, including the skull, face,
Eye, and neck are also at risk.
Following assessment of the patient's airway, circulation, and breathing, a
cervical collar may be placed if there is suspicion of trauma to the neck. Evaluation of blunt trauma to the head continues with the secondary survey for evidence of cranial trauma, including bruises, contusions, lacerations, and abrasions. In addition to noting external injury, a comprehensive neurologic exam is typically performed to assess for damage to the brain. Depending on the mechanism of injury and examination, a CT scan of the skull and brain may be ordered. This is typically done to assess for blood within the skull or
Skull fracture.
Traumatic brain injury (TBI)
Traumatic brain injury (TBI) is a significant cause of morbidity and mortality and is most commonly caused by falls, motor vehicle crashes, sports- and work-related injuries, and assaults. It is the most common cause of death in patients under the age of 25. TBI is graded from mild to severe, with greater severity correlating with increased morbidity and mortality.
Most patients with more severe traumatic brain injury have a combination of intracranial injuries, which can include diffuse axonal injury, cerebral contusions, and intracranial bleeding, including subarachnoid hemorrhage, subdural hematoma, epidural hematoma, and intraparenchymal hemorrhage.
Blunt trauma to extremities
Injury to extremities (like arms, legs, hands, feet) is extremely common.
Falls are the most common
etiology, making up as much as 30% of
Upper extremity and 60% of
lower extremity injuries. The most common mechanism for solely upper extremity injuries is machine operation or tool use. Work-related accidents and vehicle crashes are also common causes.
The injured extremity is examined for four major
System which include
,
Nervous system, vessels, and
Human skeleton.
are examined for expanding
hematoma,
bruit, distal pulse exam, and signs/symptoms of
ischemia, essentially asking, "Does blood seem to be getting through the injured area in a way that enough is getting to the parts past the injury?"
When it is not obvious that the answer is "yes", an injured extremity index or ankle-brachial index may be used to help guide whether further evaluation with
CT scan Angiography. This uses a special scanner and a substance that makes it easier to examine the vessels in finer detail than what the human hand can feel or the human eye can see.
Soft tissue damage can lead to
rhabdomyolysis (a rapid breakdown of injured
muscle that can overwhelm the
) or may potentially develop compartment syndrome (when
pressure builds up in muscle compartments damages the
and vessels in the same compartment).
Bones are evaluated with
Radiography or computed tomography if deformity (misshapen), bruising, or joint laxity (looser or more flexible than usual) are observed. Neurologic evaluation involves testing the major nerve functions of the
Axillary nerve,
Radial nerve, and
Median nerve nerves in the
Upper limb as well as the
Femoral nerve,
Sciatic nerve, deep peroneal, and
Tibial nerve nerves in the
lower extremity. Depending on the extent of injury and involved structures,
Surgery treatment may be necessary, but many are managed nonoperatively.
Blunt pelvic trauma
The most common causes of blunt pelvic trauma are motor vehicle crashes and multiple-story falls, and thus pelvic injuries are commonly associated with additional traumatic injuries in other locations.
In the pelvis specifically, the structures at risk include the
pelvic bones, the
Femur, major blood vessels such as the iliac arteries, the
urinary tract, reproductive organs, and the
rectum.
One of the primary concerns is the risk of pelvic fracture, which itself is associated with a myriad of complications including bleeding, damage to the urethra and bladder, and nerve damage.
A life-threatening concern is hemorrhage, which may result from damage to the aorta, iliac arteries, or veins in the pelvis. The majority of bleeding due to pelvic trauma is due to injury to the veins.
Blunt cardiac trauma
Blunt cardiac trauma, also known as Blunt Cardiac Injury (BCI), encompasses a spectrum of cardiac injuries resulting from blunt force trauma to the chest. While BCIs necessitate a substantial amount of force to occur because the
heart is well-protected by the
rib cage and
sternum, the majority of patients are asymptomatic.
Clinical presentations may range from minor, clinically insignificant changes to heartbeat or may progress to severe
Heart failure and
death.
Oftentimes, chest wall injuries are seen in conjunction with BCI, which confounds the presence of
chest pain experienced by most patients.
To evaluate the spectrum of cardiac injury, the American Association for the Surgery of Trauma (AAST) organ injury scale may be used to aid in determining the extent of the injury (see Evaluation and Diagnosis below).
BCI may be broken down into
Pericardium injury, valvular injuries, coronary artery injuries,
cardiac chamber rupture, and myocardial contusion.
Evaluation and diagnosis
In most settings, the initial evaluation and stabilization of traumatic injury follows the same general principles of identifying and treating immediately life-threatening injuries. In the US, the American College of Surgeons publishes the Advanced Trauma Life Support guidelines, which provide a step-by-step approach to the initial assessment, stabilization, diagnostic reasoning, and treatment of traumatic injuries that codifies this general principle.
The assessment typically begins by ensuring that the subject's airway is open and competent, that breathing is unlabored, and that circulation—i.e. pulses that can be felt—is present. This is sometimes described as the "A, B, C's"—Airway, Breathing, and Circulation—and is the first step in any resuscitation or triage. Then, the history of the accident or injury is amplified with any medical, dietary (timing of last oral intake) and history, from whatever sources that might be available such as family, friends, and previous treating physicians. This method is sometimes given the mnemonic "
SAMPLE history". The amount of time spent on diagnosis should be minimized and expedited by a combination of clinical assessment and appropriate use of technology,
such as diagnostic peritoneal lavage (DPL), or bedside ultrasound examination (FAST)
before proceeding to
laparotomy if required. If time and the patient's stability permit, a CT examination may be carried out if available.
Its advantages include superior definition of the injury, leading to grading of the injury and sometimes the confidence to avoid or postpone surgery. Its disadvantages include the time taken to acquire images, although this gets shorter with each generation of scanners, and the removal of the patient from the immediate view of the emergency or surgical staff. Many providers use the aid of an algorithm such as the ATLS guidelines to determine which images to obtain following the initial assessment. These algorithms take into account the mechanism of injury, physical examination, and patient's
vital signs to determine whether patients should have imaging or proceed directly to surgery.
In 2011, criteria were defined that might allow patients with blunt abdominal trauma to be discharged safely without further evaluation. The characteristics of such patients include:
-
absence of intoxication
-
no evidence of lowered blood pressure or raised pulse rate
-
no abdominal pain or tenderness
-
no blood in the urine.
To be considered low-risk, patients would need to meet all low-risk criteria.
Treatment
When blunt trauma is significant enough to require evaluation by a healthcare provider, treatment is typically aimed at treating life-threatening injuries, such as maintaining the patient's airway and preventing ongoing
Bleeding. Patients who have suffered blunt trauma and meet specific
triage criteria have shown improved outcomes when they are cared for in a
trauma center.
The management of patients with blunt force trauma necessitates the collaboration of an interpersonal healthcare team, which may include but is not limited to; a
Trauma surgery, emergency department physician,
Anesthesiology, and emergency and trauma nursing staff.
Treatment of abdominal trauma
In cases of blunt abdominal injury, the most frequent damage occurs in the
, and in severe situations, this can result in small intestine perforation.
Perforation of the small or
is a serious concern due to its tremendous infectious potential.
In these cases, it is essential to perform exploratory surgery to assess the internal damage, drain infected fluid in the abdomen, and clean the wound with saline.
Prophylactic antibiotics are often necessary.
In the case of multiple holes or significant damage to the blood supply of the intestines, the affected segment of tissue may need to be removed entirely.
Treatment of blunt cranial trauma
The treatment of blunt cranial trauma is dependent on the extent of the injury. A discussion between the patient and healthcare professionals will take place in order to carefully assess the patient's condition and determine the best approach for treatment. When considering the management of cranial trauma, it is crucial to ensure that the patient can breathe effectively.
Effective breathing can be monitored using the patient's blood oxygen content via a
Pulse oximetry. The goal is to maintain greater than 90% oxygen saturation in the blood.
If the patient cannot maintain appropriate blood oxygen levels on their own, mechanical ventilation may be indicated.
Mechanical ventilation will add oxygen and remove carbon dioxide in the blood.
It is also critically important to avoid low blood pressure in the setting of traumatic brain injuries. Studies have demonstrated improved outcomes in patients with
Blood pressure greater than or equal to 120mmHg.
Lastly, healthcare professionals should conduct consecutive neurological examinations to allow for early identification of elevated intracranial pressure and subsequent implementation of interventions to improve blood flow and reduce stress to the body.
Of note, patients taking
anticoagulant or antiplatelet therapy during the time of blunt cranial trauma should undergo rapid reversal of anticoagulating agents.
Treatment of blunt thoracic trauma
Nine out of ten patients with thoracic trauma can be treated effectively without a
Surgery.
If surgery is indicated, there are numerous options available. A comprehensive discussion between the patient and the surgeon will take place to carefully evaluate the best approach, tailored to the patient's specific condition and injury. Conservative measures such as maintaining a clear and open airway, oxygen support,
Chest tube, and volume resuscitation are often given to manage blunt thoracic trauma.
Oftentimes, pain control is the most basic and effective treatment approach because the presence of severe pain may lead to impairment of proper breathing, further exacerbating impaired lungs.
Pain management in thoracic trauma patients improves the ability to breathe properly on their own, encourages the excretion of pulmonary secretions, and decreases the aggravation of
inflammation and low oxygen levels in the blood.
Nonsteroidal anti-inflammatory drugs,
, or regional pain management methods, such as
local anesthetic, can be used for pain control.
Epidemiology
Worldwide, a significant cause of disability and death in people under the age of 35 is trauma, of which most are due to blunt trauma.
