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Lung Health

AS We Breathe, Our lungs exchange carbon dioxide that our tissues produce for oxygen, which the body uses to metabolize food for energy. The lungs themselves are not affected by ANI, but the muscles that help them do their work—the diaphragm and other muscles in the chest and abdomen—can be paralyzed, causing lung dysfunction. The two major problems that you may experience are mechanical: the physical movement of air in and out of your body and the risk of pneumonia. There have been remarkable improvements in preventing hospital-acquired pneumonia, which dramatically reduces the long-term problems caused by mechanical ventilation and infection.

Lung Problems

Mechanical problems: In people with SCI and TBI, the trauma from the event that caused the injury may break the ribs. This can puncture the lungs and cause bleeding into the chest that “squeezes” air out of the lungs, resulting in their collapse. If enough ribs are broken, the integrity of the chest wall will be destroyed so that it can no longer cohesively move in and out, causing a mechanical failure of lung ventilation. Treatment consists of a three eighths–inch tube inserted between the ribs and into the space between the chest wall and the collapsed lung to drain the blood and other fluids. The tube is connected to suction to speed up the drainage, which will require two to three days. A chest X-ray will monitor re-expansion of the lung, at which point the tube can be removed.

Hospital-acquired pneumonia is a lung infection acquired in the hospital more than forty-eight hours after admission. This type of pneumonia is usually more severe than other types for two reasons. First, you are already in the hospital for an illness that causes significant stress to your body’s immune system. Second, the organisms that cause infections in the hospital may be more resistant to antibiotics. After ANI, you’re especially prone to pneumonia because of five breathing problems:

• mechanical ventilation (being on a ventilator)

• secretions (fluid from the lungs that can clog the breathing tubes)

• atelectasis (collapse of parts of the lung)

• aspiration (food and material from your stomach and mouth get into your lungs; Figure 14)

• obstructive sleep apnea (periods when breathing stops while sleeping, which predisposes you to heart and lung problems; see page 000)

Treatment is similar for patients on and off ventilators. Because the incidence of multi-drug-resistant bacteria is very high, the choice of antibiotics must be individualized based on the type of bacteria that are found in sputum and blood cultures, combined with knowledge of which antibiotics the bacteria are resistant to. Usually, treatment lasts for seven days. Recovery is best assessed by patient symptoms (temperature, heart rate, sputum production), chest X-rays, and cultures.

Some people who experience pneumonia during their hospitalization will be left with long-term damage to their lungs. Damage may include chronic collapse of one or more lobes of the lung due to atelectasis, and stiffening of the lungs (fibrosis), which makes breathing much more difficult. The result is an inability to fully expand the lungs that can lead to more atelectasis, which can lead to recurrent infections, and subsequently, frequent rehospitalization—a vicious cycle. The best treatment is strengthening the muscles that help you breathe. Fortunately, there’s a simple tool called an incentive spirometer that allows you to do that—provided you use it! (More about that on page 170.)

Ventilator-associated pneumonia (VAP) is a common and serious problem for people with severe ANI. To prevent VAP, doctors take a basic and effective approach: 1) elevating the head of the bed more than 30 degrees to keep bacteria from migrating into the lungs; 2) decreasing sedation to allow patients to follow commands and staff to evaluate readiness to remove the breathing tube; 3) administering frequent oral care to remove bacteria-containing plaques; 4) using endotracheal tubes that facilitate suctioning of secretions; and 5) making patients get out of bed as soon as possible, even while still attached to the ventilator.

Getting off the ventilator (extubation): Once you are placed on a ventilator, you enter a different level of complexity in terms of your medical care, and you may need a ventilator long enough that it becomes part of your chronic care. There is a three-step process to help you get off the ventilator and return to breathing on your own. It consists of readiness testing, weaning, and extubation.

A number of criteria are used to assess readiness. These include improvement in the underlying illness and adequate oxygen in the blood while breathing on your own. Weaning involves decreasing the assistance that the ventilator provides so that you need to do a greater amount of breathing on your own. A common approach is to use the spontaneous breathing test every day. The test consists of stopping the ventilator for thirty minutes while maintaining pressure to keep your airways open and oxygen below 40 percent. A successful breathing test includes a breathing rate less than 35 breaths per minute, stable vital signs, and blood oxygen saturation greater than 90 percent. If you fail the test, the underlying problem should be identified and treated more aggressively. If you pass the test, you are ready to start the extubation process as long as your underlying condition is improving, you have a strong cough, can handle your secretions, and are mentally alert. After extubation, you should be closely monitored for at least twenty-four hours.

Bronchospasm is the suddenly contraction of the muscles that line the airways, which forces the airways to close. It’s caused by persistent inflammation around the smaller airways in the lung. The inflammatory cells secrete substances that stimulate the smooth muscle cells in the airways to contract suddenly (a spasm). If enough airways close at the same time, lung failure can occur. If you’re on a ventilator, bronchospasm will make it harder for air to get into all parts of the lung, leading to lung collapse. Treatment is directed at the underlying problems, which are inflammation and spasms. Inflammation is best treated with antibiotics, which kill the bacteria and remove the bacterial toxins that attract inflammatory cells. Spasms are best treated with drugs that keep the airway muscles dilated (bronchodilators; e.g., beta agonists like Albuterol), which are used in asthma and chronic obstructive pulmonary disease (COPD).

Tracheostomy: A tracheostomy is simply an opening into your trachea. It allows mechanical ventilation without an endotracheal tube (the clear plastic tube in the mouth or nose when on a ventilator). A tracheostomy is performed when there’s a high likelihood that you will need mechanical ventilation for more than ten days after hospital admission. A tracheostomy is easier to breathe through than an endotracheal tube, much more comfortable, and makes it easier to talk and suction out secretions.

For me, all of these advantages were worth the surgery. I wanted to start physical therapy as soon as possible, and a tracheostomy allowed me to do that. This meant I could be extubated twenty-one days after my admission to the hospital. Some people may not be able to be weaned off the ventilator even with a tracheostomy, but many can strengthen their respiratory effort without mechanical ventilation.

CPAP (continuous-positive airway pressure): If you don’t need ICU care and a ventilator but require some breathing support, there are noninvasive CPAP machines that assist breathing. These devices supply continuous positive airway pressure that keeps airways open via a mouthpiece or mask and oxygen or air as needed. They have a smaller chance of bacterial entry than ventilators and therefore result in fewer respiratory infections. Because no tracheostomy is needed, these devices also are much more comfortable.

Sleep apnea: Sleep apnea is a common condition characterized by periods of no breathing—for up to thirty seconds at a time—repeatedly throughout the night. Untreated, sleep apnea increases risk of stroke, heart attack, erectile dysfunction, and high blood pressure; it also causes daytime sleepiness, lethargy, anxiety, and fatigue. The factors that can cause sleep apnea include a dysfunctional ANS, respiratory muscle weakness, obesity, drugs that reduce spasticity by relaxing muscles, and sleeping on your back rather than your side. Sleep apnea is treated with devices such as CPAP.

Long-Term Treatments to Improve Lung Health

To combat any lung problems, it’s a good idea to improve your breathing effort. There are several therapies that can strengthen your breathing.

SCI and the Diaphragm

The diaphragm and other muscles associated with respiration are not usually affected by stroke or TBI, but SCI patients with injuries at C5 or higher lack innervation of the diaphragm and usually require a ventilator. Even when SCI occurs at lower cervical levels or in the mid-thoracic levels, coordination of breathing will be impaired, usually for a few months, but sometimes permanently. This makes it difficult to take a deep breath and exhale forcefully, which significantly impairs your ability to cough. Poor cough makes you more prone to atelectasis, aspiration, and difficulty clearing secretions.

Exercise: Like all muscles, your respiratory muscles can increase in strength and stamina with exercise. Strengthening them will enable you to do more in rehab and at home, but it’s equally important to improve your ability to cough and clear secretions, which decreases infections and the incidence of pneumonia. The most popular and effective respiratory muscle training device is the incentive spirometer (Figure 24). It’s a simple plastic device that does not require a battery or electricity. You will likely be given one in the hospital—ask for one if you’re not.

Figure 24. Incentive spirometer

To use the spirometer, hold the mouthpiece between your lips and take a long, deep inhale, making the little ball move to the highest possible position and holding it there as you continue to inhale for an increasing length of time (usually starting with fifteen seconds). When you can no longer continue the inhale, remove the mouthpiece and hold your breath for three seconds before making a deep, strong exhale. Repeat this exercise throughout the day for the prescribed number of repetitions.

It may be surprisingly difficult, at first, to get the little ball to where it should be; this exercise really makes your breathing muscles work hard! But with regular use, the incentive spirometer is highly effective and an excellent way to improve your lung function and avoid pneumonia. Once you’re able, your physical therapist will likely have you performing a cardiovascular exercise that increases your respiratory rate and heart rate. And it’s very important to strengthen your abdominal muscles, which can further assist with your inhalation. Don’t forget exhalation either, because the ability to cough is partly dependent on the elastic recoil of your rib cage and diaphragm. To improve this elasticity, perform incentive spirometry and core-stretching exercises.

Pacing electrode: A pacing electrode may be placed on your diaphragm to stimulate movement of your diaphragm, even if it isn’t innervated. The electrode and its battery are surgically implanted, and the strength and frequency of pacing are adjusted to improve your breathing effort as measured by incentive spirometry. It’s also common practice to perform pulmonary function tests if you have a pacing electrode. These tests measure the amount of air you can hold in your lungs, the rate at which they fill, and the speed and volume of an exhalation.

Vaccinations: Get the recommended vaccinations for pneumonia and a yearly influenza (flu) vaccination. I also strongly recommend that you get the COVID-19 vaccine, because COVID-19 carries serious risk of pneumonia and long term complications.

Dealing with Lung Secretions and Mucus

Mucolytics: Three types of mucolytic agents assist in clearing mucus from the lungs: 1) Expectorants increase airway water to help with mucus clearing; 2) Mucoregulators increase the movement of mucus via cough; 3) Mucokinetics suppress the mechanisms causing excess mucus secretion. Your doctor will prescribe one or more of these medicines. It’s also important to drink adequate water to thin mucus naturally.

Percussion: Percussion (slapping the back or chest) can physically mobilize and break apart mucus plugs. A caregiver can tap with fingers or an open hand where they hear no breath sounds. To help you cough the mucus out, an assistant can push upward on your stomach at the same time you cough to strengthen the force of air movement.

Posture and movement: To move mucus from the bottom of the lungs to airways higher up where it is easier to cough it out, you can perform postural drainage, which uses gravity. This is best done in a hospital bed by raising the feet and lowering the head for 15 to 20 minutes. It also helps if you increase movement by turning over in bed, or by standing up (with assistance) and moving back and forth.

 

Everything You Need to Know

After your injury, you’re more susceptible to pneumonia, which is a leading cause of death. A small number of people will require a ventilator during their hospitalization.

• Once you’re on the ventilator, there is a protocol to test your readiness to be weaned off the ventilator and extubated.

• Your best strategy to maintain healthy lungs is to avoid pneumonia with prevention. This begins in the hospital and continues after discharge. You should get the yearly influenza vaccine as well as the appropriate COVID-19 vaccine.

• Strengthen the muscles that help you breathe by using an incentive spirometer daily, and by performing cardiovascular exercise (with your doctor’s approval) at least three times a week.

• If you snore, request a sleep study; if it reveals sleep apnea, be vigilant about using the CPAP mask and machine every night.

• If you smoke, quit! And stay away from smokers; second-hand smoke damages your lungs and can increase the likelihood of pneumonia.