Dr. Martin's notes

Tuesday April 12, 2016

Thoracic injuries

 

• The most common cause of exercise-induced sudden death is some congenital cardiovascular abnormality. The three most prevalent conditions are hypertrophic cardiomyopathy, anomalous origin of the coronary artery, and Marfan's syndrome.
• Injuries to the heart, lungs, and abdominal viscera can be potentially serious and even life threatening if not recognized and managed
appropriately.
• For the coach evaluating an injury to the abdomen or thorax, the initial primary survey should focus on those signs and symptoms that indicate some life-threatening condition. Asking pertinent questions, observing body positioning, and palpation of the injured structures are critical in assessing the nature of the injury.
• Rib fractures and contusions, costal border injuries, muscle strains, and breast injuries are all common injuries to the chest wall.
• Injuries involving the lungs include pneumothorax, tension pneumothorax, hemothorax and traumatic asphyxia.
• Injuries to the abdominal wall include muscle strains, getting the wind knocked out, and the development of an inguinal or femoral
hernia.
• With any injury to the abdominal region, internal injury to the abdominal viscera must be considered. Injuries to the liver, spleen, and kidneys are among the more common athletic injuries associated with the abdominal viscera.
• Injuries to the reproductive organs in sports are much more likely to occur in the male because the male genitalia are more exposed.
• Injuries to the female breast tissues are also very prevalent in female sporting events.

MECHANICS OF BREATHING
Pulmonary ventilation (breathing) in the lungs is accomplished by changes in pressure within the chest cavity. The normal pressure within the pleural space is always negative; that is. less than atmospheric prcssure. The negative pressure helps to keep the lungs expanded.

Inhalation/Inspiration
There are two groups of intercostal muscles: external intercostals and internal intercostals. Their muscle fibers cross each other at an angle of 90 degrees. During inhalation or inspiration, the external intercostals lift the ribs upward and outward. This increases the volume of the thoracic cavity. Simultaneously the sternum rises with the ribs, and the dome shaped diaphragm contracts and becomes flattened, moving downward. As the diaphragm moves downward, pressure is exerted on the abdominal viscera. This causes the anterior muscles lo protrude slightly, increasing the space within the chest cavity in a vertical direction. A decrease in pressure results. Because atmospheric pressure is now greater, air rushes in all the way down to the alveoli, resulting in inhalation.

In exhalation, or expiration, the opposite takes place. Expiration is a passive process; all the contracted intercostal muscles and diaphragm relax.

Inspiration and expiration combined count as one respiratory movement. Thus, the normal rate in quiet breathing for an adult is about 14 to 20 breaths per minute. This rate is changeable. The respiratory rate can be increased by muscular activity, increased body temperature, and certain pathological disorders such as hyperthyroidism. It changes with sex: females have a higher rate, at 16 to 20 breaths per minute. The respiratory rate also changes with age. For example, at birth the rate is 40 to 60 breaths per minute; at 5 years, it is 24 to 26 breaths. The body's position also affects the respiration rate. When one is asleep or prone, the rate is 12 to 14 breaths per minute; when in a sitting position, it is 18; when in a standing position, it is 20 to 22 breaths per minute. Emotions play a role in decreasing or increasing the respiratory rate.

LUNG CAPACITY AND VOLUME
To measure how much air you can hold (your lung capacity), a device called a spirometer measures the volume and flow of air during inspiration and expiration. By comparing the reading with the norm for a person's age, height, weight, and sex, it can be determined if any deficiencies exist. Tidal volume is the amount of air that moves in and out of the lung's with each breath. The normal amount is about 500 ml. Total lung capacity includes tidal volume, inspiratory reserve, expiratory reserve, and residual air. The normal amount is 6,000 ml.

Asthma, a disease that affects the lungs, has become the most common long term disease in children. Asthma affects a considerable percentage of athletes as well. During an asthma attack, the muscles around the airways tighten, or spasm, and the lining inside the airways swells or thickens and gets clogged with thick mucus. This makes it harder to move air in and out of the lungs. Asthma can be controlled by the use of special medications and inhalers.

Exercise-induced asthma is a condition in which vigorous physical activity triggers airway narrowing. This reversible airway obstruction occurs during or after exertion. This type of asthma can occur in otherwise healthy people who do not have chronic asthma. Exercise is the only stimulus for their asthma symptoms. Exercise-induced asthma may occur in people who have chronic asthma and are not aware that their symptoms during exercise are a manifestation of asthma.
The symptoms of exercise-induced asthma include coughing, wheezing, dyspnea (difficulty in breathing), and chest tightness.

A rib fracture is a break in the bony structure of the thorax. These injuries are most often the result of a direct blow to the ribcage. Rib fractures can be serious and cause additional damage to the organs that they normally protect. Displaced fractured ribs can puncture the lungs and the heart and so must be considered life threatening.

Pneumothorax occurs when air enters the thoracic cavity between the chest wall and the lung. The difference in pressure causes the lung to collapse. Pneumothorax can also occur if an intense impact tears the lung itself.
Three additional conditions may arise as a result of a chest wound—sucking chest wound, spontaneous pneumothorax, and tension pneumothorax. Signs of a pneumothorax are severe chest pain, difficulty breathing, cyanosis (bluish discoloration of the skin), unequal expansion of the right and left sides of the chest upon inhalation, and the absence of breathing sounds on the side of the collapsed lung.

Hemopneumothorax
This condition, also known as a hemothorax, can occur with both open and closed chest injuries, and often accompanies a pneumothorax. In a hemopneumothorax, blood accumulates in the pleural space between the chest wall and the lung. This compromises the lungs' ability to operate, as does a pneumothorax. With the loss of blood, the certified athletic trainer must be concerned about the onset of shock. Signs and symptoms of this injury are similar to those of a pneumothorax.

Blows to the Solar Plexus
The most common infra-abdominal injury is a blow to the celiac plexus (solar plexus). This is commonly known as "having the wind knocked out. A blow to the upper middle region of the abdomen, whether from another athlete or hitting the ground when falling, can cause this condition. Although the athlete may become very anxious because of perceived inability to breathe, this injury is usually of short duration, and no treatment is necessary. The condition responds to a few moments of rest and reassurance.

Side stitches can occur during vigorous exercise, such as running. They seem to occur more commonly in novice exercisers who have not yet established proper pacing and whose breathing tends to be quick and shallow. About 30 percent of all runners will experience side stitches at some point.

The abdominopelvic cavity is actually one large cavity, with no separation between the abdomen and pelvis. To avoid confusion, the areas of this cavity are usually referred to separately as the abdominal cavity and the pelvic cavity. The abdominal cavity contains the stomach, liver, gallbladder, pancreas, spleen, small intestine, appendix, and part of the large intestine. The kidneys are close to but behind the abdominal cavity. The urinary bladder, reproductive organs, rectum, remainder of the large intestine, and appendix are in the pelvic cavity.

Kidney Contusion- Contusions to the kidney are uncommon in athletics, but they do occur. The certified athletic trainer should suspect a kidney contusion when any athlete sustains a violent blow to the upper posterior abdominal wall. This can occur in contact sports, such as football and hockey, and occasionally in other sports. An athlete who has sustained a kidney contusion may have pain located high in the posterior abdomen and radiating into the lower abdominal region. He or she may show signs of shock, nausea, vomiting, rigidity of the back muscles, and hematuria (blood in the urine).

Liver Contusion -The liver, which lies just beneath the ribs on the right, is the largest solid organ in the abdomen. The liver is a large mass of blood vessels and cells packed tightly together. Blood flow to the liver is very high, because blood that is pumped from the abdomen passes through the liver before it returns to the heart. An injury to the liver is a probable life-threatening injury that, demands immediate medical attention. Liver contusions from athletics are not common. However, a hard blow to the right side of the ribcage can tear or contuse the liver.

Liver contusions can cause severe bleeding and shock. This requires immediate surgery for repair. An injury to the liver commonly produces a referred pain just below the right scapula, right shoulder, and substernal area; the pain may also radiate to the left side of the chest. The EMS system must be activated immediately for a liver contusion, a life-threatening injury. Treat for shock and reassure the athlete until help arrives.

Spleen injuries are responsible for many deaths each year, so any suspected injury to this area is a medical emergency. The spleen is the organ of the abdominal region most commonly injured. Injury to the spleen normally results from a blow to the left upper quadrant, the lower left ribcage, or the left side of the back. Pain will be located in the upper-left quadrant of the body. Referred pain may be felt in the left shoulder, radiating one-third of the way down the left arm. This referred pain is called Kehr's sign. The athlete may go into shock and have low blood pressure. The medical staff must activate the EMS system for immediate transportation to the hospital. The athlete should be treated for shock. Calm and reassure the athlete until help arrives.

Hernias- The National Center for Health Statistics estimates that about 5 million people in the United States have abdominal hernias. A hernia is a protrusion of abdominal tissue through a portion of the abdominal wall. Inguinal (groin) hernias, which occur most often in men, and femoral hernias, which most often occur in women, are the prevalent types. Hernias can be caused by a chronic cough, straining to lift heavy objects, persistent sneezing, straining during bowel movements or urination, and obesity. Participating in athletics does not increase the risk of developing an abdominal hernia.

A hernia usually first becomes noticeable as a bulge somewhere in the abdomen or pelvic area, or in the scrotum for men. A hernia may cause sharp or dull pain that worsens when having a bowel movement, during urination, or while lifting a heavy object. Most hernias eventually require surgery. Hernias normally are not emergency situations, but the athlete should see a physician as soon as possible.