Respiratory Study Guide for the CCRN

Pleural Space Abnormalities

Pneumothorax

Air-leak syndromes are an acute condition that may result from trauma or spontaneous alveoli rupture. In this event, pressure builds in the alveoli sacs until the wall of these structures pulls away from the perivascular tissue. This separation of the alveolar wall and the perivascular sheath causes alveoli rupture and collapse as air exits the lungs into the perivascular space.

The medical term for an air leak into the pleural cavity is pneumothorax. Lung collapse may be partial or complete and can be defined by the location of the displaced air and how the alveoli rupture occurred. There are four primary locations of air displacement in the event of pneumothorax. Air in the pleural cavity is simply called a pneumothorax. Air in the pericardial sac is known as pneumopericardium, and air in the peritoneal cavity is known as pneumoperitoneum. If the air extends to the subcutaneous tissue, noted by a crackling feeling with palpation or the superficial tissues, the event is known as subcutaneous emphysema.

A pneumothorax may be spontaneous, traumatic, or iatrogenic (medically acquired due to prior intervention). A spontaneous pneumothorax occurs despite any predisposing events and may either be primary or secondary. Primary spontaneous pneumothorax occurs in healthy lungs, whereas secondary spontaneous pneumothorax occurs in diseased lungs with structural alveolar changes. Traumatic pneumothorax occurs due to injury to the chest wall, lung, or pleural space. It may be direct or indirect based on the injury that occurred. Tension pneumothorax events, which involve tracheal deviation and changes in hemodynamic status, are most commonly caused by traumatic lung injuries. Finally, iatrogenic pneumothorax occurs when air leaks from the alveolar tissues due to medical interventions. Iatrogenic pneumothorax may result from barotrauma/volutrauma, placement of a subclavian central line, or cardiac/thoracic surgical procedures.

Symptoms may vary; however, the most common symptom is acute pleuritic pain, usually on the affected side. Nurses may also assess for decreased breath sounds. A chest x-ray is frequently used to assess for and diagnose pneumothorax. An ultrasound may also be used to identify any pneumothorax following a traumatic event.

Most pneumothorax events are treated with a water-seal chest-tube thoracostomy system. In the event of a tension pneumothorax, an acute needle decompression should be performed prior to chest tube insertion. Some patients may qualify for a “watch and wait” therapy of small pneumothorax events. In this case, patients will be provided with oxygen therapy and observed for several hours. If a repeat x-ray after 6 hours shows no worsening of the air accumulation, the patient may be discharged home and instructed to have a follow-up x-ray in 24 hours.

Hemothorax

Hemothorax occurs when blood enters the pleural space. This occurs most commonly due to chest trauma; however, it can also be caused as a result of damage to the pleural space from medical interventions, infarction of the lung tissue, tuberculosis, or cancer growth. Symptoms of hemothorax include chest pain, anxiety/sense of impending doom, decreased blood pressure, increased work of breathing, shortness of breath, and cool clammy skin. Patients may experience hemodynamic instability, shock, and respiratory compromise.

Diagnosis of hemothorax is usually determined by chest x-ray or CT scan. Testing of the pleural fluid may also be performed to determine the composition of the fluid (bloody generally indicates hemothorax). A chest tube should be inserted and set to suction to drain the pleural space. This may also be used to attempt to treat the bleeding. However, if the bleeding is not stopped, a thoracotomy may be required to investigate the lung tissues and pleural space. Depending on the severity and cause of the hemothorax, other medical interventions may include oxygen support (ranging from nasal cannula to endotracheal tube placement), blood transfusion, and hemodynamic support.

Nurses must monitor patients with hemothorax closely. Chest tube drainage should be measured every 1-2 hours. Drainage greater than 150 mL/hr for 2-4 hours may indicate continued/active bleeding that must be addressed by a healthcare provider.

Empyema

Empyema is the presence of pus or infection in the pleural cavity. It can occur secondary to pneumonia, hemothorax, parapneumonic effusion, trauma, post-thoracic surgery, or esophageal rupture. It may also occur as a primary infection, though this is less common. Patients at higher risk for empyema include those with diabetes mellitus, immunosuppression, acid reflux, IV drug abuse, and alcohol abuse.

Symptoms and diagnosis of empyema is similar to pneumonia. Patients may exhibit symptoms such as shortness or breath, cough, decreased lung sounds, shallow breathing patterns, sputum production, fever, and chest pain. If antibiotic therapy is not improving a patient’s symptoms within a few days, the occurrence of empyema should be considered. Diagnosis can be obtained with chest x-ray, chest CT, pleural ultrasound, and/or pleural fluid culture.

To treat empyema, the pus and infected pleural fluid must be drained and treated. A percutaneous thoracentesis can often be used in simple cases of empyema to drain the pus through a needle inserted into the pleural space. Some patient will require chest-tube placement to help drain the pus. Antibiotic therapy should be started or continued for several weeks (generally 2-6 weeks). Intrapleural medication injection is generally not used. Surgical intervention via video-assisted thoracotomy (VATS) or open thoracotomy may be required if the infection persists despite the previous measures.

Pleural Effusion

Fluid collection in the pleural space is known as pleural effusion. Pleural effusion may be caused by viral infection, pneumonia, or heart failure. It can also be secondary to cancer, radiation, or thoracic surgery. Symptoms of pleural effusion include chest pain, non-productive cough, shortness of breath, and orthopnea.

Two types of pleural effusion can be diagnosed. These are transudative pleural effusion and exudative effusion. Transudative pleural effusion is most commonly caused by heart failure. This is due to increased blood vessel pressures or low blood protein pushing fluid into the pleural space. Transudative pleural fluid is characteristically watery. Exudative effusion is caused by blocked blood or lymph vessels related to inflammation, infection, injury, or obstruction (blood clot, tumor, plaques, etc.). Exudative effusion fluid is characteristically protein-rich.

Diagnosis of pleural effusion can be made via chest x-ray, CT scan, or thoracic ultrasound. A thoracentesis may be performed to determine the fluid contents and drain some of the existing fluid. Many patients will require chest tube placement to drain the fluid and help re-expand the lung tissue(s). Patients must have any underlying conditions/causes to the pleural effusion treated to reduce the chances of effusion recurrence. Surgical intervention via video-assisted thoracoscopic surgery (VATS) or thoracotomy (open thoracic surgery) may be required to address the fluid leak.

Anatomic Pulmonary Changes

Pulmonary changes may occur due to chronic or acute pulmonary illness. The two most common changes to occur include pulmonary fibrosis and pulmonary hypertension. These diagnoses will be reviewed in the upcoming sections.

Pulmonary Fibrosis

Pulmonary fibrosis is scarring of the lung tissue. It is usually an idiopathic condition. The scar tissue causes the lungs to thicken, which in turn reduces adequate oxygen exchange. It is a progressive condition and the average survival rate is five years after diagnosis. While there is no known direct cause of pulmonary fibrosis, it may be associated with environmental exposures (asbestos, smoke, wood dust, metal dust) or genetics. People between the ages of 40-70 and men more often than women will acquire this condition.

Symptoms of pulmonary fibrosis include dry cough, shortness of breath, fatigue, weight loss, and fingertip and nail clubbing. It can be diagnosed by physical assessment, chest x-ray, CT, PFTs, and biopsy. There is no cure for pulmonary fibrosis and patients are offered minimal supportive options. Oxygen therapy may be initiated when hypoxemia becomes a concern. Lung transplant may be considered for some patients as well.

Pulmonary Hypertension

Pulmonary hypertension is defined as high blood pressure in the arteries of the pulmonary system and heart. This is usually caused by damage to or obstruction of the pulmonary vascular bed that impairs the vessels’ ability to easily receive blood from the right ventricle. Increased pulmonary arterial pressure leads to increased pulmonary vascular resistance. This puts increasing pressure on the right ventricle and, over time, will cause hypertrophy of the chamber. As the right ventricle remodels, the interventricular septum deviates and creates tricuspid regurgitation. This is known as cor pulmonale. If left untreated, progressive right heart failure and eventually death will occur.

Diagnosis of pulmonary hypertension can be obtained via right-sided heart catheterization. A systolic pulmonary artery pressure greater than 30 mmHg with a mean greater than 25 mmHg are diagnostic for pulmonary hypertension. If the pressure is maintained at a high rate, pulmonary hypertension can progress into pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) can be primary or secondary. Primary PAH is also known as idiopathic PAH. It can result from changes in immune function, pulmonary emboli, sickle cell disease, collagen disease, Raynaud’s, and contraceptive use. It may occur despite these conditions or may also be genetic. Secondary PAH may ensue after pulmonary vasoconstriction from hypoxemia. Causes of hypoxemia may include COPD, sleep apnea, kyphoscoliosis, obesity, smoking, altitude sickness, interstitial pneumonia, and neuromuscular disorder. If there is an obstruction or disease in the pulmonary bed (e.g., pulmonary emboli, vasculitis, tumor, etc.), presence of chronic cardiac disease, or history of congenital cardiac defects, secondary PAH may be triggered as well.

Treatment of pulmonary hypertension and pulmonary arterial hypertension includes treating the underlying cause, controlling cardiac and pulmonary symptoms, and preventing complications. Pharmacologic therapy includes the use of calcium channel blockers to provide vasodilation (some patients may respond to this) and pulmonary vascular dilators. Common pulmonary vascular dilators include IV epoprostenol (Flolan®), subcutaneous treprostinil sodium (Remodulin®), and oral bosentan (Tracleer®). These medications can be used to both control symptoms and prolong life. Anticoagulant therapy may be used to prevent pulmonary emboli. Diuretics may be used to reduce the pulmonary fluid burden and peripheral edema. If pharmacologic therapy does not reduce the patient’s symptoms and manage their pulmonary hypertension adequately, a heart-lung transplant may be considered to improve the rate of survival.

Thoracic Events

Disruption or injury to the thoracic cage or internal components can have significant patient outcomes. Some of these outcomes can be used to improve overall survival and quality of life whereas others may be traumatic and decrease the patient’s quality of life. Review the following events that occur regarding the thoracic anatomy and pulmonary system in preparation for your test.

Thoracic Surgery

Thoracic surgery may be indicated in patients who have had extensive pulmonary trauma or who have chronic conditions that have remodeled the lungs beyond repair. The goal of pulmonary surgery is to improve lung compliance and reduce complications from restricted pulmonary expansion. Two primary pulmonary surgeries include lung volume reduction surgery and pneumonectomy and lung surgery.

Lung volume reduction surgery may be indicated if a patient has approximately 20-35% of their lung tissue that does not work appropriately. In the procedure, surgeons remove the ineffective lung tissue to allow better expansion of the healthy lung tissue. This reduces the workload of the functioning lung structures. This therapy is most commonly performed for patients with chronic emphysematous COPD. Chronic emphysematous COPD generally affects both lungs, so removal of the diseased lung tissue is performed bilaterally. Patients with cardiac disease or unilateral emphysema may only qualify for removal of the most affected lung tissue.

Long-term outcomes for patients who undergo lung volume reduction surgery are generally high, especially if their surgical risk is low and their emphysematous lung tissue is in the upper lobes. The procedure also reduces the need for lung transplant in these patients.

In some patient cases, removal of an entire lung may be indicated. This procedure is known as a pneumonectomy. Pneumonectomy procedures may be either simple or extrapleural. In a simple pneumonectomy, the entire lung is removed without any additional structures. An extrapleural pneumonectomy involves removal of the lung, part of the diaphragm, and the pericardium on the same side.

Specific surgical precautions must be taken to avoid contamination or damage to the remaining lung. Patients should be positioned prone throughout the surgery and/or have bronchus blockers to the remaining lung. Indications for pneumonectomy include cancerous lesions, severe bronchiectasis, severe hypoplasia, unilateral lung destruction, pulmonary hemorrhage, lobar emphysema, chronic pulmonary infections with destruction, and occasionally pulmonary hypertension. Following a pneumonectomy, patients should be monitored for pulmonary infection, decreased compliance of the remaining lung, dyspnea, hypoxia, and shortness of breath.

In some cases, a patient may not need a total lung pneumonectomy but rather just partial removal of lung tissue. A lobectomy is the removal of one or more lung lobes. Indications for this partial lung removal include tubercular lesions, abscesses or cysts, cancer, traumatic injury, or bronchiectasis. Patients should be monitored for postoperative hemorrhage, infection, and pneumothorax. Nurses will be in charge of managing the patient’s chest tube(s) following this procedure. The chest tubes may be placed to prevent the accumulation of air into the newly opened space or to reduce fluid buildup that may constrict or collapse the remaining lobes.

Segmental resections and wedge resections may also be used to remove smaller portions of the pulmonary tissue. In segmental resection, the patient may have a bronchovascular segment or small lesions removed. Patients who have wedge resections have a wedge of tissue removed. This procedure is used primarily for removal of small peripheral lesions, granulomas, or blebs. Just like with any pulmonary trauma or surgical intervention, nurses must monitor the patient for worsening respiratory symptoms, infection, and pneumothorax.

Thoracic Trauma

Pulmonary Hemorrhage

Pulmonary hemorrhage is an acute, often deadly event when the pulmonary vessels are ruptured due to either a blunt or penetrating trauma. This is considered a medical emergency and immediate surgery is required to repair the injured vessel. Even with immediate surgical correction, many patients will die from the event or complications following.

Symptoms of pulmonary hemorrhage include dyspnea, cough, fever, and acute respiratory failure. When suspected, the nursing staff should immediately place a large-bore IV to replace fluid. Assess for hemorrhagic shock and replace fluids as necessary. Type and screen labs should be performed to match replacement blood product to the patient. If the patient is stabilized, CT scans may be used to identify the source of the bleeding so more focused repair can occur.

Patients may also have a hemothorax or pneumothorax, often evidenced by mediastinal shift, in the event of pulmonary trauma and hemorrhage. Additional symptoms of these include severe respiratory distress, decreased breath sounds, and dullness on auscultation due to the presence of air or blood in the pleural space. The patient may be prepared for chest tube insertion. Monitor for severe, acute blood loss and exsanguination with insertion of the chest tube. Use fluid and blood replacement as indicated through a large-bore IV. If there is more than 1500 mL of blood initially drained, the patient is hemodynamically stable, a new tension hemothorax develops, or the patient continues to bleed more than 300 mL/hr, the patient will likely be prepared for a thoracotomy.

Nurses may be responsible for managing some of the patient’s needs. Keep the patient as calm as possible to reduce stress on the respiratory system, use suctioning modestly to avoid aspiration, prepare the patient for intubation (if indicated), and maintain appropriate intravenous (IV) access.

Pulmonary Contusion

Pulmonary contusion occurs when the lung is injured via direct force. It occurs when the parenchymal structures are injured, resulting in bleeding and edema. The patient may experience intrapulmonary shunting and fluid-filled alveoli and interstitium as a result of the injury. The pulmonary system suffers as the lungs experience decreased compliance and ventilation due to the injury.

Diagnosis of pulmonary contusion is best assessed with a CT scan. The patient may also have other pulmonary concerns, such as broken ribs or pneumothorax, that may make diagnosis more difficult. Symptoms with pulmonary contusion include mild dyspnea progressing into severe dyspnea, hemoptysis, and acute respiratory failure. Treatment measures include supplemental oxygen, monitoring for respiratory failure via arterial blood gases and frequent respiratory assessments, intubation and mechanical ventilation with PEEP for severe respiratory distress, fluid management, and respiratory physiotherapy to mobilize excess fluid and clear secretions.

Fractured Rib

Fractured ribs generally occur from severe trauma. Common traumas that result in rib fractures include motor vehicle accidents and physical abuse. The biggest concern with fractured ribs involves the concern for underlying structure damage. In particular, if the upper two ribs are fractured, the trachea, bronchi, and great vessels should be assessed for injury. Right-sided ribs below rib 8 may induce liver injury, whereas left-sided ribs below rib 8 may involve splenic injury.

Side or rib pain is the primary symptom of rib fractures. Patients may also experience shallow breathing due to chest compression or increased pain. Complications of shallow breathing include atelectasis and pneumonia. Chest x-ray or CT are standard for diagnosing rib fractures. Pain should be controlled with an analgesic; supplemental oxygen may be given to support respiratory effort; and splints may be fitted to help support the respiratory cage. If patients have underlying injury or require a thoracotomy, surgical fixation (ORIF) may be indicated.

In the event that at least three or more adjacent ribs are fractured on both the anterior and posterior side, the patient will experience flail chest. The ribs, having no connecting bone, then float free of the rib cage. Paradoxical respirations occur due to the inability of the chest wall to support changes in intrathoracic pressure during breathing. This decreases the ability of the lungs to inflate and deflate properly, causing respiratory distress.

Treatment of flail chest is similar to the treatment of fractured ribs. The chest should be stabilized on one side to strengthen the chest wall and promote appropriate ventilation. Analgesics should be given for pain. Pulmonary clearance interventions, such as physiotherapy, should be used to prevent atelectasis. Surgical fixation is only recommended in the event of underlying tissue injury and thoracotomy.

Tracheal Perforation

Tracheal perforation may result due to external, penetrating injury or as a complication of intubation or percutaneous dilation tracheostomy (DPT). Occasionally, aspirated foreign objects may erode the tracheal structures. Early diagnosis and intervention is key to preventing death from this injury.

Nurses should assess patients at risk for severe respiratory distress, hemoptysis, stridor, progressive dysphonia, pneumothorax, pneumomediastinum, and subcutaneous emphysema. Diagnosis may be achieved via CT scan, chest x-ray, or bronchoscopy. Treatment of tracheal perforation includes intubation to facilitate rest and healing of small lacerations or surgical repair for larger lacerations or severe respiratory distress.

Patients experiencing anemia, severe hemorrhage, hemodynamic instability, and shock may require the use of blood products to help stabilize their condition. Transfusion-related acute lung injury (TRALI) is an adverse reaction following an infusion of blood product(s). All blood products that include plasma have risk of causing TRALI. TRALI is life-threatening and can cause severe respiratory compromise, increased mortality, and prolonged recovery. A patient experiencing TRALI will start to develop symptoms within six hours following the transfusion of one or more blood units. Symptoms of TRALI include acute hypoxemia (\(O_2\) <90% on room air), pulmonary edema, dyspnea, tachypnea, hypotension, and fever.

There are two categories of TRALI, one caused by an immune-mediated response and one with no immune-mediated response. In immune-mediated TRALI, the injury is due to a response of anti-HLA antibodies present in the blood of either the donor or recipient. These antibodies activate in the event of foreign presence recognition and react with leucocytes, causing damage to the surrounding tissues. Immune-mediated TRALI accounts for 65-85% of TRALI events. In non-immune mediated TRALI, there is no antibody involvement. Instead, biologically active compounds accumulate, causing a cascading bodily reaction of inflammation, endothelial damage, pulmonary capillary fluid leakage, and pulmonary edema.

Risk factors for TRALI include being female or receiving blood from a female donor, older age (65+), increased age of blood products, end-stage liver disease, cardiovascular disease, frequent transfusions or massive blood transfusion protocol, sepsis, and current respiratory compromise. Diagnosis of TRALI can be determined based on presence of recent blood transfusion with acute symptoms and radiographic imaging. Chest x-ray and/or CT may show bilateral pulmonary infiltrates without cardiac compromise or fluid overload.

Nurses should monitor closely for both subtle and significant symptoms of TRALI. If TRALI is suspected during active transfusion, the nurse must first stop the transfusion and initiate supportive measures such as oxygen administration. The blood product and tubing should not be thrown away, but rather returned to the facility’s blood center for further investigation of the product and testing of potential donor antibodies. If respiratory compromise is severe, intubation may be required for appropriate ventilation management. Prone positioning may be used to improve oxygenation and reduce additional pulmonary injury from increased mechanical ventilatory pressures. Extracorporeal membrane oxygenation (ECMO) may also be required if mechanical ventilation is inadequate and the patient advances into severe acute hypoxemic respiratory failure.

Decreased time on mechanical ventilation can improve patient outcomes. Nurses should advocate for daily sedation holidays to assess the patient’s pulmonary status and potential for extubation. Discontinuation of mechanical ventilation should be performed as soon as determined safe to help prevent any additional pulmonary compromise.