imagining rib injuries: CT…really?…not

Wednesday, August 17, 2016

The availability of medical technology in the 21st century has a tendency for patients to demand its use, regardless of whether the information it can reveal actually matters. Nothing better highlights this issue than the overuse of radiology by pro sports. This week’s prime example is Carson Wentz, Philadelphia’s first round rookie quarterback, and leader of the future. Towards the end of the game against Tampa Bay, Wentz is hit on the right side and has pain in his right ribs.

ESPN.com quoted Eagle coach, Doug Pederson: “Carson felt some discomfort and soreness as we began this morning’s practice. We decided to limit him throughout the remainder of practice and, as a precaution, sent him for a CT scan after practice. The scan revealed a hairline fracture in his ribs.We do not know an exact timetable for his return, but we hope to have him back before the end of the preseason.”

FYI: fracture, broken, cracked all mean the same thing

Perhaps the CT seems like a reasonable care plan, with the coach and the team worried about their player, but in reality, this is not the standard of care that most people would receive. In the real world, people who hurt their ribs are often examined and may or may not get a simple chest x-ray. CT is definitely not routine.

Here is the thinking. The chest wall, rib cage and muscles have a couple of important jobs. The first is to protect the contents of the chest cavity (thorax) including the heart, lungs and great vessels (aorta, vena cava among others), as well as organs in the upper abdomen like the spleen and liver. The second, is the muscles of the chest wall and the diaphragm that are responsible for the work of breathing. When taking a deep breath, the ribs swing out, the diaphragm pushes down and air is sucked into the lungs like a bellows.

If the rib cage is injured, pain may prevent that process from working well. Deep breaths don’t occur and a multi-step process ends up in the complication of pneumonia. It doesn’t matter whether ribs are bruised or broken, it’s a matter of the pain that causes the problem:

  • Pain decreases the ability to take a deep breath
  • Without that deep breath, the alveoli, small sacs at the end of the bronchial tree, where oxygen gets transferred to the blood stream, can’t pop open. This is called atelectasis
  • With atelectasis, the lungs can’t clear normal secretions and debris and the gunk is left to accumulate in the warm, dark environment. This increases the risk of lung infection
  • A lung infection is called pneumonia and the symptoms include, fever, cough and shortness of breath.
  • Pneumonia associated with chest injury is not a good combination because it becomes that much tougher to take a deep breath to help clear the infection. This failure of pulmonary toilet increases the risk of complications.

While rib injuries hurt, the bigger concern is not the pain but whether damage occurred beneath the injured ribs. If that suspicion is low and physical exam does not point to disaster, then the test of choice is a simple chest x-ray, looking for a collapsed lung (pneumothorax) or a bruised lung (pulmonary contusion). Specific rib x-rays aren’t needed and a CT of the chest to look for rib fractures is definitely overkill.

chest ct rib fx

Black arrow points to rib fracture. White arrows show collapsed lung. Plain X-ray might miss the fracture but not the pneumothorax.

Regardless of whether the rib cage is bruised or a rib is broken, the treatment is the same: pain control and deep breaths to prevent atelectasis and pneumonia and the healing time is 4 to 6 weeks. Just like any other broken bone or torn muscle, it takes that long to get better. Chest injuries may take longer, since the area that is damaged is not allowed to rest and heal. A sore arm can be put into a sling to rest, but a sore chest is asked to work every few seconds, mandating a deep breath to prevent pneumonia.

While NFL coaches can’t order CT scans, team doctors can sign off on that request, and the rationale is presumably to make certain nothing terrible was hiding inside Mr. Wentz’ chest. Aside from increasing his lifetime accumulation of radiation exposure, there would be little risk for the test but also very little reward. Perhaps the major issue will occur later, when fans who see an NFL player gets a CT scan for a chest wall injury, will demand their share of high tech medicine, when low tech might do just as well.

It’s the part of the doctor’s job to explain what tests are needed, and what the next steps are once those results are back. In this regard, doctors and patients can learn from an NFL coach. There always needs to be a game plan for whatever situation might arise on the field. Similarly, there needs to be a game plan based on the history, physical exam and whatever the test results might show. And while Coach/Dr. Pederson may order a CT as a precaution, that shouldn’t necessarily fit into most people’s game plans. Just because there is a test that can be done, doesn’t mean that it is the right thing to do.

This entry was tagged , , , , , , ,


collapsed lung

Sunday, December 7, 2014

The concept of transparency does not exist when it comes to trauma. For that reason, docs need a high index of suspicion when any victim walks or is carried through the door. The idea is this…most injuries can be taken at face value, but complications can exist, even in the most stable patient. For that reason, the concept of ruling out bad things is a routine thinking pattern in medicine. It does not mean that every test known to man has to be ordered, history and physical exam are powerful tools, but at least the doctor has to go through the mental gymnastics to be comfortable with the patient’s stability.

Every week, the NFL provides medical teaching moments. This time, it was learning that Dallas quarterback, Tony Romo, may have been playing for weeks with broken ribs. Bear receiver, Brandon Marshall goes down after a tackle, struggles to get up and ends up in the hospital with broken ribs and a collapsed lung. Same injury but Romo escapes without the complication that beset Marshall.

Breathing seems so simple and yet becomes very complicated when the chest wall is damaged. Normally, we breathe like a bellows, the ribs swing up and out, the diaphragm pushes down and air gets sucked into the lungs. That happens because the lungs are held against the chest wall by negative pressure between the two pleura, one lines the lung and the other lines the chest wall. Most people recognize pleural as the shiny skin when eating ribs. A pneumothorax or collapsed lung occurs when air gets into the space between those two linings and breaks the seal between the two. In trauma, a broken rib can cause a small tear into the lung tissue allowing that air leak to happen, but not always.

pleural-cavity-location

The pneumothorax is just one of the complications that have to be considered. It’s easy to be distracted by the pain of the broken fib and not concentrate on what’s important, the ability of the patient to breathe. The lung collapse is not all or nothing, it may be tiny and only seen as an incidental finding on a chest x-ray or Ct scan, it can be a complete collapse or the collapse can be somewhere in between. A smaller pneumothorax may not be appreciated on physical examination and for that reason a plain chest x-ray is an important screening tool in patients with chest injury. In addition to the collapsed lung, the doc will be looking for a contusion or bleeding in the chest. It is not meant to look for broken ribs. While more broken ribs presume increased force of trauma and increased risk of pneumothorax, the purpose of the test is to look for the lung damage and not any rib injury.

http://www.dreamstime.com/royalty-free-stock-photography-pneumothorax-image26701217

So Tony Romo keeps playing and Brandon Marshall goes to the hospital and gets a tube put in his chest. The way a traumatic pneumothorax is treated depends on how much air has escaped into the pleural space and how much the lung has collapsed. A tiny pneumothorax can be watched but larger ones need to have the air sucked out and the negative pressure re=established for the breathing mechanism to work again. A chest tube is placed through a stab incision in between the ribs and threaded into place. It is then hooked up to suct8ion and the patient is observed. If all goes well, the lung injury heals itself, the air leak stops and the tube can be removed in a couple of days. If all doesn’t go well, surgery may be required to repair the lung.

cchest tube

Aside from the lung, the ribs protect all sorts of vital structures from the heart and great vessels (think aorta, vena cava and others) in the chest, to the liver and spleen in the abdomen. Predicting the future is a fool’s game for doctors caring for trauma patients. Some, like Romo, will have an injury and do well. Others like Marshall will gradually decompensate with complications. Trauma is a worthy adversary and can lull doctors into a false sense of security when victims initially don’t look “too” injured. Just a reminder why medicine is a combination of science and art.

 

Image attriburions:

education-portal.com, dreamstime.com. @bmarshall twitter feed

 

 

This entry was tagged , , , , , , ,