Jill Blackburn, 59, is a patient in the telemetry step-down unit. Having undergone coronary artery bypass graft (CABG) surgery 3 days ago,
she's receiving 3 liters/minute of oxygen by nasal
cannula. During your assessment, her SpO2 reading is 91% and her temperature is 100.1° F (37.8° C). Auscultating her lungs, you hear diminished breath sounds on the left and fine inspiratory crackles in both posterior bases.
You ask Mrs. Blackburn to perform incentive spirometry and she growls, "Don't you know they just cut me open from my neck to my navel? Leave me alone!"
Surgery places a patient at risk for atelectasis, (collapsed alveoli) and subsequent pneumonia. Mrs. Blackburn's current signs and symptoms indicate that she may indeed have these complications. In this article, I'll explain how you can help her now and how you can help other patients avoid similar problems.
How surgery increases risk
Regardless of the surgical procedure, 90% of patients who have general anesthesia develop some degree of atelectasis afterward. The signs and symptoms include tachypnea, tachycardia, hypoxemia, and diminished breath sounds. In areas of consolidation, you'll hear bronchial breath sounds and fine, late-inspiratory crackles. Chest X-rays reveal opacification of the affected lung segment or lobe.
The following factors increase the risk of atelectasis in a surgical patient:
- Anesthesia causes the diaphragm to relax and move into the chest cavity, reducing functional residual capacity (FRC) and compressing the alveoli. The longer the anesthesia, the greater the risk.
- Low ventilator settings, particularly for tidal volume, may cause hypoventilation and alveolar collapse.
- Delivering too much oxygen to the alveoli over an extended period can wash out nitrogen (which shares alveolar space and helps keep the alveoli open) to trigger atelectasis.
- Postoperative hypoventilation can be a problem after abdominal or thoracic surgery if pain prevents the patient from deep breathing and effective coughing. Retained secretions and reduced ventilation can lead to mucus plugs in her airway and increase atelectasis.
- Smoking or chronic obstructive pulmonary disease (COPD) raises the risk by increasing mucus production and decreasing mucociliary action to clear secretions. Chronic air trapping and increased FRC compress the airways, reducing their diameter and increasing the work of breathing. Finally, air trapping and increased FRC push down on the diaphragm to cause ineffective diaphragmatic contractions.
- Coronary artery bypass graft surgery poses several risks. Opening the chest and exposing the lungs to air can trigger alveolar collapse. Or the surgeon might compress lung tissue by infusing lavage fluid into the pericardial sac or by moving the lungs in order to reach the coronary arteries.
Prevent and respond to the problem
These measures during and immediately after surgery help prevent atelectasis:
- administering appropriate tidal volume on the mechanical ventilator
- administering positive end-expiratory pressure (PEEP) to increase FRC
- administering supplemental oxygen at the lowest setting needed to prevent hypoxemia
- weaning and extubating the patient from mechanical ventilation as soon as possible.
For both surgical and medical patients, positioning and encouraging deep breathing and coughing are key nursing techniques to help prevent atelectasis.
Positioning. Keep Mrs. Blackburn in a semi-Fowler's position and occasionally in high-Fowler's position to increase her lung capacity and encourage deeper breaths. Get her up in a chair and walking as soon as possible.
Deep breathing and coughing, especially with the aid of an incentive spirometer. (See Putting on airs.) Using this calibrated device, the patient takes low, sustained maximal inspirations to total lung capacity, holds her breath, and exhales passively to help keep the alveoli open. (This is done about 10 times every hour while she's awake.) Adequate pain control along with coaching and reinforcement are essential to help her master the proper technique. A patient with COPD may benefit from positive-pressure ventilation. (See the Photo Guide on page 46 of this issue.)
Teaching the technique
The ideal time to teach a patient incentive spirometry is preoperatively so she can comfortably practice. Explain that breathing exercises will help her keep her lungs inflated and prevent problems such as pneumonia. (For tips on visual reinforcement, see Picturing a balloon.) Use this teaching sequence:
Assemble the incentive spirometer and check the package insert to determine your patient's target volume based on height and age. Explain how the device will help her do breathing exercises and show her the parts. Have her sit up if she can.
Model the breathing exercise. Explain that she'll place the mouthpiece in her mouth, pull in a full, slow, deep breath, hold it for 5 seconds, then slowly let out her air. Mimic the technique: Hold an imaginary mouthpiece to your mouth, inhale a slow deep breath, hold it 5 seconds, and slowly exhale.
Coach her through the maneuver. If she needs supplemental oxygen, attach the tubing to the spirometer port. Help her find her target on the volume indicator.
Facing your patient to coach her, have her inhale slowly and watch the piston rising in the volume indicator. As she inhales up to the target volume, have her watch the flow indicator and keep it in the target zone to ensure slow inhalation. After each full inhalation, count out loud to five so she knows how long to hold her breath before exhaling. Have her do this exercise 10 times, pausing to breathe normally a few times between each one.
Review her technique. The patient may forget some directions and make one of several common errors, such as blowing into the spirometer rather than inhaling. Or her inspirations may be fast and deep, pulling the diaphragm down so air enters open alveoli and misses those that are collapsed. Taking a deep breath but failing to hold it for 5 seconds also bypasses atelectatic areas. Taking in a slow, deep breath and holding it encourages air movement into those areas to start reopening the closed alveoli.
Have her end with two coughs. After 10 incentive spirometry maneuvers, your patient should cough to move out chest secretions. If she's scheduled for surgery on her chest or abdomen, teach her to place a pillow over the area and wrap her arms around it. Instruct her to take a slow, deep breath, squeeze the pillow tightly against the painful area, and let out a medium cough, then a second strong one, then stop (repeated coughing is ineffective and causes more pain). Mimic this action as you did the inspiration technique.
Encourage practice. Place the incentive spirometer within easy reach on your patient's bedside table. Each time you enter the room, ask her to do the exercise, or ask if she needs help.
Education pays off
Once Mrs. Blackburn's pain is under control, you spend a few minutes teaching her about incentive spirometry and coaching her in the technique of splinting a pillow against her chest. She starts doing the exercise and achieves 60% to 80% of her inspired volume goal each hour. Within 24 hours, she's receiving oxygen by nasal cannula at 1 liter/minute, her breath sounds are clear, and her temperature is 98.9° F (37.2° C). Coughing with vigor, she's maintaining her SpO2 level at or above 94% while walking in the hall. Within 48 hours, she's been weaned off supplementary oxygen and is preparing for discharge.
Mrs. Blackburn is an example of how education helps motivate a patient to combat atelectasis. Your careful instruction and demonstration of incentive spirometry have helped her overcome postoperative respiratory problems and prevent possible pulmonary complications.
Picturing a balloon
Use imagery to help your patient understand the importance of deep breathing and coughing:
"Have you ever blown up a balloon, tied the opening, and set it aside? The next day, it's lost air and shrunk.
"After surgery, tiny air sacks in your lungs called alveoli can lose air too, partly because of the surgery and partly because of other factors. For example, staying in bed keeps you from doing things that make you breathe deeply, and pain makes deep breathing and coughing difficult, so the alveoli can lose air and close up like the balloon. Once they collapse, they're hard to reopen.
If you don't take deep breaths and cough, secretions may stay in your lungs, making breathing harder and providing a good site for infection. I'll help you take deep breaths and learn how to cough without causing a lot of pain to keep the alveoli open and move secretions out of your lungs."
Duggan M, Kavanagh B. Pulmonary atelectasis: A pathogenic perioperative entity. Anesthesiology
. 102(4):838–854, 2005.
Wilkins R. Lung expansion therapy. In Wilkins R, et al. (eds). Egan's Fundamental of Respiratory Care
, 8th edition. St. Louis, Mo., Mosby, 2003.