Tube Thoracostomy

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Chapter 10

Tube Thoracostomy

Thomas D. Kirsch and Jordan Sax

Review Box 10-1 Tube thoracostomy: indications, contraindications, complications, and equipment.

Tube thoracostomy is a procedure used to evacuate an abnormal accumulation of fluid or air from the pleural space and can be performed on an elective, urgent, or emergency basis. Air or fluid can accumulate in the pleural space as a result of spontaneous or traumatic pneumothorax, pleural fluid accumulation of blood, malignancy, infection (empyema), or lymph (chylothorax). The first modern methods to evacuate the contents of the pleural space were developed in the 19th century, but these techniques did not become widespread until 1918, when they were used to treat postinfluenza empyema. Military experience demonstrated that thoracic drainage combined with antiseptics and antibiotics reduced mortality related to thoracic trauma from 62.5% during the Civil War, to 24.6% in World War I, and to 12% in World War II.¹

Pathophysiology

The lung is surrounded by two layers, the parietal pleura, which lines the interior of the chest wall, and the visceral pleura, which covers the lungs. They are separated by a thin layer of lubricating fluid within the “pleural space.” A small negative pressure within the pleural space helps keep the lung inflated and the two layers closely apposed. With inspiration, the negative intrathoracic pressure increases and leads to expansion of the lung from an influx of air. If the pleural space is disrupted, air, blood, or other fluid can accumulate in between the two layers of the pleura and the normal pressure gradient is compromised. This interferes with normal inspiratory-induced inflation and leads to “collapse” of the lung. As the amount of fluid or air increases, respiratory function worsens and symptoms of dyspnea are produced, often with pleuritic chest pain and anxiety. The degree of respiratory compromise depends on the volume of fluid or air in the pleural space, the patient’s age, baseline pulmonary status, and the integrity of the chest wall. The positive pressure accumulation of air associated with tension pneumothorax leads to severe respiratory dysfunction and cardiovascular compromise.

A pneumothorax is caused by the presence of air in the pleural space and the loss of negative pressure (Fig. 10-1). Air can enter the pleural space from the outside as a result of a penetrating injury or internally from a ruptured lung bleb or damaged trachea. Iatrogenic causes from needle procedures such as subclavian venous cannulation, transthoracic biopsy, thoracentesis, positive pressure ventilation (PPV), or cardiopulmonary resuscitation (CPR) are also common (Fig. 10-2). Pneumothoraces are commonly divided into “open” and “closed.” An open pneumothorax indicates that the skin and underlying soft tissue sustained an injury that penetrated into at least the pleural space.

Figure 10-1 Pneumothorax. A, Anteroposterior chest radiograph of a right-sided, seemingly small, simple pneumothorax (PTX). Note the absence of peripheral lung markings on the right side and the distinct line indicating the edge of the collapsed lung (arrow). Although this appears to be a small PTX, it produced significant dyspnea in this patient with chronic obstructive pulmonary disease and therefore required a chest tube. B, Computed tomography scan showing the extent of the collapse. Adhesions kept part of the lung expanded.

Figure 10-2 A, After successful cardiopulmonary resuscitation and intubation, this patient began to deteriorate, with a precipitous drop in blood pressure and decreasing oxygen saturation. It was believed that the cause of the initial cardiac arrest was returning. Marked subcutaneous air was noted in the scrotum and abdominal wall, but little air was noted in the chest wall tissue. The subcutaneous air had curiously tracked via tissue planes, a distinctly unusual place for air to accumulate. B, A chest tube (arrow) quickly reversed the decompensation. C, This patient suffered respiratory arrest from heroin injected into a neck vein (note the extensive scar). After bag-mask resuscitation the respiratory depression returned, he was unresponsive to naloxone, and he was very difficult to ventilate. He had a small pneumothorax (PTX) from a nick in the lung from the neck injection.

Spontaneous (Closed) Pneumothorax

Spontaneous pneumothorax is caused by rupture of a subpleural lung bleb with little or no trauma and can be categorized as either primary or secondary based on the presence of underlying lung disease. Primary spontaneous pneumothorax occurs in a patient without overt lung disease. The typical patient with spontaneous pneumothorax is a tall, thin, 20- to 40-year-old male smoker (Fig. 10-3). Secondary spontaneous pneumothoraces occur in patients with underlying lung or pleural disease, including emphysema, chronic bronchitis, asthma, Marfan’s syndrome, infection, and neoplasm. The morbidity, mortality, and long-term complications associated with pneumothorax increase in patients with underlying lung disease. Whereas a primary pneumothorax may be selectively observed or simply aspirated, a secondary pneumothorax often requires a more aggressive approach to management.

Figure 10-3 Spontaneous pneumothorax. A, Spontaneous pneumothorax in a young male patient. There is nearly total collapse of the right lung, and lung markings are absent lateral to the visible pleural reflection (arrow). Note also the slight deviation of the mediastinum to the contralateral side. B, The patient was treated with a pigtail catheter inserted in the second intercostal space in the midclavicular line (arrow). Note that the lung has totally reexpanded and the mediastinum has shifted back to the midline.

The sudden onset of pleuritic chest pain and dyspnea with exertion or at rest is the most common finding. More subtle manifestations occur with little or no pain and only mild dyspnea on excursion that the patient may ignore for days. A person with a small spontaneous pneumothorax may never seek medical attention, and the process will resolve without treatment. The signs and symptoms do not always correlate well with the size or cause of the collapsed lung. Tube thoracostomy is the most common treatment, but new trials suggest that conservative management or aspiration of first-time primary pneumothoraces results in similar outcomes as traditional tube thoracostomy, though with fewer complications, shorter hospital stay, and lower cost. Conservative management and aspiration are both reasonable initial interventions in clinically stable patients. However, to date no high-quality clinical trials have definitely demonstrated that aspiration is a superior treatment methodology.2–4 Rarely, a spontaneous pneumothorax may be bilateral or progress to tension pneumothorax, a potentially life-threatening condition that is described in more detail later in this chapter.

Traumatic Closed Pneumothorax

A closed pneumothorax may also result from an injury without penetration of the chest wall, usually from a rib fracture that penetrates the lung, but also when an alveolus or bleb ruptures after blunt trauma. The air leak from a closed pneumothorax is generally self-limited but can rarely progress to a tension pneumothorax.

Traumatic Open Pneumothorax

An open pneumothorax occurs when the chest wall is penetrated and the negative intrapleural pressure is lost. Each breath can increase intrapleural pressure. If the diameter of the chest wound is greater than the diameter of the trachea, with each respiratory attempt, air moves preferentially through the chest wall opening rather than down the trachea and thus prevents meaningful ventilation of the involved lung.

Tension Pneumothorax

An open pneumothorax can occasionally be manifested as a tension pneumothorax, which is a life-threatening condition that requires immediate intervention. A tension pneumothorax occurs when an injury creates a one-way “flap valve” mechanism that allows air into the pleural space with inspiration but then closes with expiration and traps the air (Fig. 10-4). The progressive accumulation of air in the pleural space leads to ipsilateral complete lung collapse and then impingement on the mediastinum with a shift of the heart toward the uninvolved side, which restricts ventricular filling and subsequently decreases cardiac function. This severe disruption in both respiratory and cardiac function can lead to hypotension and reduced ventilation (both hypoxia and CO₂ retention) and eventually to cardiopulmonary collapse.

Figure 10-4 Traumatic tension pneumothorax. A and B, Pathophysiology of a tension pneumothorax. During inspiration, air enters the pleural space through a one-way valve either from the outside or from the lung itself. On expiration, the injury/valve closes and traps increasing amounts of air in the pleural space. Eventually, the mediastinum shifts and cardiac filling and ultimately cardiac output are compromised. C, This elderly patient sustained a tension hemopneumothorax after slipping and falling on ice. The left hemithorax is very dark (radiolucent) because of total collapse of the left lung (large white arrow). Note the dramatic shift of the mediastinum to the right, indicative of tension. Multiple posterior rib fractures are present but are difficult to appreciate on this film (small white arrows). The air-fluid level (black arrow) indicates the presence of fluid in the pleural cavity in addition to air. D, A computed tomography scan of the same patient redemonstrates the findings seen on the conventional radiograph.

A tension pneumothorax is usually caused by penetrating chest injuries but can result from fracture of the trachea or bronchi, a ruptured esophagus, the presence of an occlusive dressing over an open pneumothorax, and PPV. Patients with chest or lung injuries who are treated with PPV are at much greater risk for the development of a tension pneumothorax. Consequently, any patient with a penetrating thoracic injury (even without immediate evidence of a hemothorax or pneumothorax) may be a candidate for a “prophylactic” chest tube before mechanical ventilation. A pneumothorax may also develop in patients with asthma or emphysema from the high pressure required for ventilation, followed by a tension pneumothorax.

Hemothorax

Hemothorax is an accumulation of blood in the pleural space as a result of injury to the heart, great vessels, or vessels of the lungs, mediastinum, or chest wall. Bleeding from the lung parenchyma is low pressure and usually self-limited or ceases when a chest tube is inserted. On the other hand, bleeding from an intercostal artery, a pulmonary artery, or the internal mammary artery can be profuse and often requires surgical intervention.

Empyema and Effusions

An empyema is an accumulation of pus in the pleural space, usually from a parapneumonic infectious effusion (Fig. 10-5). An empyema can also be caused by violation of the thoracic space by surgical procedures (e.g., tube thoracostomy), trauma, and esophageal perforation. Pleural infection rates have increased 3% per year in the United States in the last 2 decades. The bacteriology of pleural infections appears to track closely with classification of pneumonia as community or hospital acquired. Nearly 60% of cases of community-acquired pneumonia are caused by Streptococcus pneumoniae species, whereas Staphylococcus species account for nearly 45% of hospital-acquired infections.⁵

Figure 10-5 Empyema. This 34-year old patient with a history of alcoholism had fever, cough, pleuritic chest pain, and hypoxia. A, Posteroanterior chest radiograph demonstrating nearly total opacification of the right hemithorax. The presence of a meniscus (large arrow) suggests a pleural effusion. However, small lucent areas (small arrows) can be seen throughout the opacity, which may represent air bronchograms in consolidated lung parenchyma. Thus, a computed tomography (CT) scan was performed. B, CT revealed nearly total collapse of the right lung with only a small portion of the apex remaining inflated (white arrow). A massive pleural collection was found with gas bubbles throughout (black arrows), suggestive of pyogenic empyema. Tube thoracostomy was performed and more than 1700 mL of purulent fluid was drained. Fluid cultures grew Streptococcus anginosus.

Chylothorax

Chylothorax results from injury to the thoracic duct during placement of a central line, operative injury, or chest trauma. Primary thoracic duct injury is usually asymptomatic because the chyle initially collects extrapleurally and may not begin to fill the pleural cavity for 2 to 10 days. As the fluid accumulates, respiratory symptoms slowly develop. The chest radiograph demonstrates a pleural effusion, and the diagnosis is made when thoracentesis reveals a milky fluid with a high fat and lymphocyte content and 4 to 5 g/dL of protein. Definitive treatment is either repeated thoracentesis or tube thoracostomy combined with parenteral alimentation until the volume of chyle decreases.

Diagnosis

Symptoms

The symptoms of patients with abnormal collections in the pleural space range widely depending on the size of the pneumothorax, the rapidity of accumulation, the age of the patient, and the presence of an underlying lung disease. Specific symptoms range from mild dyspnea with exercise and pleuritic chest pain with small disruptions to hypotension or severe dyspnea in those with tension pneumothorax. With a spontaneous pneumothorax, 95% of patients complain of the sudden onset of sharp, pleuritic chest pain, shoulder pain, or both. Sixty percent of patients experience dyspnea, and 12% have a mild cough. Dyspnea and anxiety are more common in older patients.

Tension pneumothorax must be considered in any patient with sudden respiratory or cardiac deterioration and in intubated patients who become difficult to ventilate because of increased airway pressure, hypotension, or elevated central venous and pulmonary artery pressure. Severe dyspnea, restlessness, agitation, and a feeling of impending doom will develop rapidly in conscious patients with tension pneumothorax. They are usually tachycardic and tachypneic and can quickly become hypotensive.

The symptoms of hemothorax can be similar to those of pneumothorax but may be accompanied by hypotension as blood accumulates in the pleural space. The onset of symptoms with effusions is usually much more gradual, with increasing shortness of breath and dyspnea on exertion occurring over a period of days to weeks.

Physical Examination

Unstable Patients

During the initial phase of resuscitation (airway, breathing, circulation, disability), consider the diagnosis of pneumothorax in patients who are tachycardic, hypotensive, and dyspneic. Similar symptoms occur with pulmonary embolism, pericardial tamponade, and severe pneumonia. Conduct multiple examinations because the diagnosis of tension pneumothorax by physical examination can be very subtle. Use the phrase “look, listen, and feel” as your guideline. Observe the chest wall, which may reveal asymmetric chest expansion, and the neck and forehead veins, which may be distended, even if the patient is hypotensive. The trachea may be deviated away from the side of the pneumothorax. When percussing the chest wall, hyperresonance on the affected side and subcutaneous emphysema may be present. Auscultation may demonstrate diminished breath sounds on the injured side. In one prospective study, the sensitivity, specificity, and diagnostic accuracy of auscultation for hemothorax and pneumothorax were 84%, 97%, and 89%, respectively.⁶ A false-negative auscultation is more likely than a false-positive one.⁶ Pulsus paradoxus may be evident. For intubated patients, an early sign of tension pneumothorax is difficulty ventilating because of increased airway pressure.

In injured patients with apnea, hypotension, or cardiopulmonary arrest, diagnose and treat a tension pneumothorax by immediate needle or catheter decompression thoracentesis; do not take the time taken to obtain and review a radiograph because delay can lead to increased morbidity and mortality in patients with this emergency condition. Confirm the diagnosis of tension pneumothorax by observing rapid improvement in vital signs and a rush of air through the needle.

Stable Patients

In more stable patients (and those with smaller accumulations) the findings on physical examination are less sensitive, and a chest radiograph or even a computed tomography (CT) scan is usually necessary to make a definitive diagnosis. Physical findings may include unilaterally decreased breath sounds, tachypnea, tachycardia, decreased tactile fremitus, increased resonance with percussion, or subcutaneous emphysema, but the examination may reveal little to no abnormalities with a small pneumothorax. Patients with a pneumothorax involving less than 20% of the hemithorax will often have completely normal findings on chest examination, including equal breath sounds (Fig. 10-6). Pleural fluid collections are difficult to detect by physical examination, particularly with less than 500 mL of fluid in the pleural space. Breath sounds may be decreased and percussion of the bases may be dull.

Figure 10-6 Smaller pneumothoraces such as this (note the faintly visible pleural reflection [arrow], absence of lung markings at the left apex, and relative crowding of vessels at the left hilum) can be difficult to see on radiographs and even harder—if not impossible—to appreciate on physical examination. Patients with a pneumothorax of less than 20% will often have completely normal findings on chest examination, including equal breath sounds.

Parapneumonic empyemas are often accompanied by fever, cough, chest pain, dyspnea, and purulent sputum (see Fig. 10-5). Physical examination may reveal diminished breath sounds, dullness on percussion, egophony, and diminished tactile fremitus on the involved side. Fever will often develop in patients with an indwelling chest tube and empyema. The pleural fluid drainage may be copious and purulent, and respiratory symptoms may worsen.

Radiography

Plain Radiographs

A chest radiograph is an essential tool for diagnosing a pneumothorax in stable patients. In unstable patients with a potential tension pneumothorax the diagnosis should be made clinically, but in rare cases a portable radiograph may be obtained in the resuscitation room if carefully monitored by a clinician. The best plain radiographs for hemothorax or pneumothorax are traditional upright inspiratory posteroanterior and lateral chest radiographs. Diagnostic sensitivity is not increased with an expiratory upright chest radiograph. Upright is preferable to a supine chest radiograph, particularly for a hemothorax, because even with large amounts of blood there may only be slight differences in the density of the lung fields since the blood may layer out evenly. With an upright chest radiograph, 300 to 500 mL of fluid is needed to cause blunting of the costophrenic angle (Fig. 10-7).⁷ When CT is not available, other useful views include a bilateral decubitus chest radiograph, with the pneumothorax expected to be seen on the side away from the table as gravity pulls the affected lung down.

Figure 10-7 Hydropneumothorax. This radiograph is an excellent example of a hydropneumothorax. When accumulated fluid in the chest cavity is seen as a straight line on a radiograph (an air-fluid level [black arrow]) with no meniscus up the side, air must be present in the pleural space. In this patient the pneumothorax is readily visualized, with no lung markings seen lateral or superior to the pleural reflection (white arrows).

On a chest radiograph the partially collapsed lung of a pneumothorax appears as a visceral pleural line with no pulmonary markings beyond it (see Figs. 10-1, 10-3, 10-6, and 10-7). It is easy to initially mistake large blebs for a pneumothorax or to identify the scapular border, skin folds, or indwelling lines as a pneumothorax, but a CT scan quickly resolves the issue (Fig. 10-8). Other radiographic findings include hyperlucency of the affected hemithorax, a double diaphragm contour, increased visibility of the inferior cardiac border, better visualization of pericardial fat at the cardiac apex, and possibly a depressed diaphragm. If subcutaneous air is noted on the chest radiograph of a patient with blunt chest trauma, it can be assumed that the air came from an injured lung and that a pneumothorax exists.

Figure 10-8 Pneumothorax and bullous emphysema. This patient had a history of severe chronic obstructive pulmonary disease and arrived at the emergency department in respiratory distress. A, On the chest radiograph, both apices are relatively radiolucent, and faint lines can be seen coursing through that are not clearly blebs or pleural reflections (arrows). B, A computed tomography scan was obtained and defined the pathology in detail. In the right apex there is no pneumothorax, but rather large blebs are present (small white arrows). On the left a pleural reflection is clearly visible (large white arrow), indicative of pneumothorax. Subcutaneous air is also noted in the thoracic soft tissues (black arrows), thus further supporting the diagnosis of pneumothorax. (This finding is also evident on the chest radiography but was overlooked on the initial interpretation.)

It is difficult to accurately predict the size of a pneumothorax on plain radiographs. Greater accuracy in predicting size can be accomplished with a CT scan. With a tension pneumothorax, the chest radiograph reveals lung collapse, a depressed hemidiaphragm on the affected side, and a shift of the mediastinum and trachea to the opposite side (see Fig. 10-4). With a bilateral pneumothorax, no mediastinal shift may be seen.

Thoracic CT

The gold standard for diagnosis is a thoracic CT scan, which can detect a pneumothorax not easily visible on a plain radiograph. CT scans of the chest are much more sensitive than plain radiographs in detecting hemothorax and pneumothorax. They are also more accurate for estimating the size and other characteristics of a pneumothorax (see Figs. 10-1, 10-4, and 10-8). CT scans are not routine for diagnosis of a pneumothorax but are more useful for hemothoraces and other fluid collections. They also offer invaluable information on the cause of such abnormalities. A CT scan may be useful when the diagnosis is unclear or when looking for small amounts of pleural fluid. CT scans are particularly helpful in determining whether an empyema is loculated or draining successfully. About 10% of trauma patients with normal findings on a chest radiograph will demonstrate a small hemothorax or pneumothorax.^7–9 The clinical significance of a small, previously undetected occult injury is probably not great, and it has been suggested that a small pneumothorax seen only on CT may be left untreated and simply observed in otherwise stable patients. Some patients with a pneumothorax seen only on CT may also safely undergo PPV without placement of a chest tube.⁹

Ultrasound

Ultrasound is useful in diagnosing both hemothoraces and pneumothoraces, and its use is reviewed in the Ultrasound Box.10,11

Ultrasound

Recognizing Pneumothoraxby Christine Butts, MD

To evaluate for pneumothorax, a high-frequency transducer should be used to ensure a high degree of resolution. In a supine patient the transducer should be placed on the anterior chest wall in the midclavicular line at approximately the second to third intercostal space (Fig. 10-US1). The depth of the image should be adjusted until the ribs are seen as brightly echogenic (white) arcs with acoustic shadows behind them. The pleural line can be found just deep to the ribs and is represented as a horizontal, echogenic line (Fig. 10-US2). In a normal lung the visceral and parietal pleural layers are directly opposed to one another (save for a thin layer of pleural fluid). When the patient breathes in and out, the layers “slide” past each other to allow the lungs to expand. When this is viewed with ultrasound, the pleural line can be seen to slide back and forth with patient respiration. This is referred to as the “slide sign.” In cases in which this interface is disrupted (such as by a pneumothorax), the sliding is lost. When these patients are evaluated with ultrasound, the pleural line will be seen as a static echogenic line that does not change with respiration.

Figure 10-US1 Proper positioning of the probe for evaluation of pneumothorax.

Figure 10-US2 Ultrasound image of the pleura as seen with a high-frequency transducer. The pleura can be recognized as a hyperechoic (white) line (arrow) that normally moves back and forth with respiration. Identifying the rib, along with its accompanying shadow (arrowhead), often aids in identifying the pleura because it will lie immediately deep to the rib.

Although the slide sign carries significant sensitivity for ruling out a pneumothorax, other secondary confirmatory findings should be sought as well.¹

Comet tail artifacts may be seen in a normal lung. These are hyperechoic vertical lines that extend deep to the pleural interface (Fig. 10-US3). Typically, they will be seen in small numbers in a normal lung. Patients in whom a pneumothorax is present are noted to lack comet tails because this artifact arises from the normal pleural interface, which is disrupted. The presence of comet tails may be used by the sonographer to further rule out a pneumothorax.^2,3

Figure 10-US3 This image demonstrates two key artifacts seen in a normal lung. As with the previous image, the pleura is recognized as a hyperechoic horizontal line deep to the ribs (at the far right and left of the image). A comet tail, a small vertical line, can be seen extending deep to the pleura (arrow). This is a normal artifact created by the pleura, and its presence aids in ruling out a pneumothorax. A-lines, or a series of horizontal lines extending deep to the pleura, can also be seen (arrowhead). These artifacts may be seen both in normal lung and in the presence of pneumothorax.

M-mode may also be used to further evaluate for the presence of a pneumothorax. M-mode is used to evaluate objects in motion and plots a linear representation of motion on screen. Objects that move toward the surface (or toward the transducer) are represented by an upward deflection. Objects that move away from the transducer are represented by a downward deflection. Objects that are not in motion are represented by a solid line.

In a normal patient, the pleura will slide back and forth as the patient breathes. Because this motion is neither toward nor away from the transducer but instead is parallel, the motion will be seen as a series of hazy lines deep to the pleura. The overlying soft tissue is not in motion and will be seen as a series of clear, flat lines. This typical appearance is described as the “seashore” sign (Fig. 10-US4).

Figure 10-US4 Seashore sign seen in a normal lung. This M-mode image shows movement of the pleura. The solid lines at the top of the image represent the immobile skin, soft tissue, and muscle. The hazy lines at the bottom of the image represent the back-and-forth movement of the normal pleura.

In patients in whom a pneumothorax is present, no motion is detected by ultrasound. Therefore, the M-mode tracing will show clear, flat lines throughout the frame. This is referred to as the “stratosphere” or “bar code” sign (Fig. 10-US5).

Figure 10-US5 Bar code sign consistent with a pneumothorax. This M-mode image shows lack of movement of the pleura. Unlike the previous image, the solid lines can be seen to continue past the point of the pleural line. Because the presence of the pneumothorax causes the pleura to appear stationary, no movement is seen in this image.

References:

1. Blaivas, M, Lyon, M, Duggal, S. A prospective comparison of supine chest radiography and bedside ultrasound for the diagnosis of traumatic pneumothorax. Acad Emerg Med. 2005;12:844–849.

2. Lichtenstein, D, Meziere, G, Biderman, P, et al. The comet-tail artifact: an ultrasound sign ruling out pneumothorax. Intensive Care Med. 1999;25:383–388.

3. Chan, SS. Emergency bedside ultrasound to detect pneumothorax. Acad Emerg Med. 2003;10:91–94.

Indications for Tube Thoracostomy

Pneumothorax

Tube thoracostomy is by far the most common treatment of all types of pneumothoraces, but controversy exists over the treatment of small traumatic and spontaneous primary pneumothoraces. However, the American College of Chest Physicians has developed useful guidelines for the management of primary and secondary spontaneous pneumothoraces (Box 10-1).¹²

Box 10-1

Guidelines of the American College of Chest Physicians for the Management of Primary and Secondary Spontaneous Pneumothoraces

Primary Spontaneous Pneumothorax (No Underlying Lung Disease)

A clinically stable patient must have all of the following present: respiratory rate lower than 24 breaths/min, heart rate higher than 60 beats/min or less than 120 beats/min, normal blood pressure, room-air O₂ saturation higher than 90%, and the ability to speak in whole sentences between breaths.

Clinically Stable Patients with Small Pneumothoraces (<3-Cm Apex-to-Cupola Distance)

Clinically stable patients with small pneumothoraces (PTXs) should be observed in the emergency department (ED) for 3 to 6 hours and be discharged home if a repeated chest radiograph excludes progression of the PTX (good consensus). Patients should be provided with careful instructions for follow-up within 12 hours to 2 days, depending on the circumstances. A chest radiograph should be obtained at the follow-up appointment to document resolution of the PTX. Patients may be admitted for observation if they live distant from emergency services or follow-up care is considered unreliable (good consensus). Simple aspiration of the PTX or insertion of a chest tube is not appropriate for most patients (good consensus) unless the PTX enlarges. The presence of symptoms for longer than 24 hours does not alter the treatment recommendations.

Clinically Stable Patients with Large Pneumothoraces (≥3-cm Apex-to-Cupola Distance)

Clinically stable patients with large PTXs should undergo a procedure to reexpand the lung and should be hospitalized in most instances (very good consensus). The lung should be reexpanded by using a small-bore catheter (≤14 Fr) or placement of a 16- to 22-Fr chest tube (good consensus). Catheters or tubes may be attached either to a Heimlich valve (good consensus) or to a water seal device (good consensus) and may be left in place until the lung expands against the chest wall and the air leaks have resolved. If the lung fails to reexpand quickly, suction should be applied to a water seal device. Alternatively, suction may be applied immediately after placement of a chest tube in all patients managed with a water seal system (some consensus).

Reliable patients who are unwilling to undergo hospitalization may be discharged home from the ED with a small-bore catheter attached to a Heimlich valve if the lung reexpanded after the removal of pleural air (good consensus). Follow-up should be arranged within 2 days. The presence of symptoms for longer than 24 hours does not alter management recommendations.

Secondary Spontaneous Pneumothorax

Clinically Stable Patients with Small Pneumothoraces

Clinically stable patients with small PTXs should be hospitalized (good consensus). Patients should not be managed in the ED with observation or simple aspiration without hospitalization (very good consensus). Hospitalized patients may be observed (good consensus) or treated with a chest tube (some consensus), depending on the extent of their symptoms and the course of their PTX. Some of the panel members argued against observation alone because of a report of deaths with this approach. Patients should not be referred for thoracoscopy without prior stabilization (very good consensus). The presence of symptoms for longer than 24 hours did not alter the panel members’ recommendations.

Clinically Stable Patients with Large Pneumothoraces

Clinically stable patients with large PTXs should undergo placement of a chest tube to reexpand the lung and should be hospitalized (very good consensus). Patients should not be referred for thoracoscopy without prior stabilization with a chest tube (very good consensus). The presence of symptoms for longer than 24 hours did not alter the panel members’ recommendations.

This is meant to be a guide, and clinical judgment should always be used.

From Baumann MH, Strange C, Heffner JE, et al, for the AACP Pneumothorax Consensus Group. Management of spontaneous pneumothorax: an American College of Chest Physicians Delphi consensus statement. Chest. 2001;119:590.

Chest tube placement is probably not necessary in healthy patients with small primary spontaneous or isolated small traumatic pneumothoraces in the absence of respiratory compromise or concomitant injuries or when PPV will not be required. With no intervention, a small pneumothorax will resolve over a period of days to weeks. Supplemental oxygen will speed the process of lung reexpansion by increasing the rate of pleural air absorption. No controlled studies have been conducted to compare the various interventions for primary spontaneous pneumothorax, and there is wide variation in treatment approaches. In particular, no significant difference has been found between simple aspiration and tube drainage with regard to the immediate success rate, early failure rate, duration of hospitalization, and 1-year success and pleurodesis.¹³ Needle aspiration is associated with reduced analgesia requirements, lower pain scores, and a lower percentage of patients being hospitalized. Recent studies have shown excellent short- and long-term outcomes after video-assisted thoracoscopic treatment (VATS) of primary and secondary spontaneous pneumothorax, and rates of recurrence are lower than after other treatment modalities. However, VATS continues to have a higher complication rate than simple tube thoracostomy does, with 4.6% of patients with spontaneous pneumothorax experiencing serious side effects as a result of the procedure.^14,15

In patients with a simple pneumothorax, prolonged suction is rarely required, and the tube can simply be attached to a Heimlich valve or underwater seal.16–18

Treatment is different for patients with a secondary spontaneous pneumothorax because the presence of underlying disease leads to more serious compromise and more frequent complications. In patients with chronic obstructive pulmonary disease, malignancy, cystic fibrosis, pneumonia, and tuberculosis, a chest tube cannot usually be avoided.

The underlying lung pathology of a patient with a spontaneous pneumothorax is best initially evaluated with CT. Frequently, this is followed by diagnostic or therapeutic visual inspection of the lung and pleural space by fiberoptic thoracoscopy. Extensive evaluation is not, however, usually recommended for the first episode of a small primary pneumothorax. When patients have recurrent spontaneous pneumothoraces, further evaluation (CT, thoracoscopy) and evaluation for surgical treatment are indicated. Patients who have had one spontaneous pneumothorax have a 30% to 50% chance of recurrence within 2 years, and after the second pneumothorax there is a 50% to 80% chance of a third developing. Surgery may be recommended for a first pneumothorax in the following situations: life-threatening tension pneumothorax, massive air leaks with incomplete reexpansion, an air leak persisting 4 days after a second tube has been placed, associated hemothorax with complications, identifiable bullous disease, or failure of easy reexpansion in patients with cystic fibrosis.

In patients with traumatic causes, the urgency and type of treatment depend primarily on the stability of the patient; a hypotensive patient with a tension pneumothorax requires immediate decompression with a chest tube or needle thoracostomy, whereas a patient with normal vital signs and a small pneumothorax may be observed initially. Emergency needle thoracostomy is only a temporary solution for a compromised patient with a pneumothorax. Once done, needle thoracostomy necessitates an ipsilateral tube thoracostomy. Other factors that modify treatment include the patient’s age, the size of the pneumothorax, whether bilateral pneumothoraces are present, and whether the current episode represents a recurrence. A chest tube is usually indicated for a pneumothorax.

Because of the risk for tension pneumothorax, a chest tube should be considered in all patients with a penetrating chest injury if PPV will be used or if they will be transported a long distance for definitive care. However, CT scans of trauma victims have demonstrated that many patients with small pneumothoraces that would have escaped detection with standard radiographs have safely undergone PPV without clinically evident pneumothorax developing. Close observation for signs of tension pneumothorax is necessary for patients in whom a chest tube is not placed and PPV is used.

Hemothorax

Tube thoracostomy is the treatment of hemothorax, but it is also used to monitor the amount and rapidity of blood output, which determines the need for additional interventions, including video-assisted thoracoscopy or open thoracotomy. About three fourths of patients with a traumatic hemothorax can be managed by tube thoracostomy and volume replacement alone. The remaining patients will require immediate or delayed elective thoracotomy. The indications for surgery after an acute hemothorax vary somewhat between authors but are summarized in Box 10-2. Early institution of blood replacement is recommended for patients with massive hemothoraces (>2000 mL) because they are often associated with continuing hemorrhage. Autotransfusion of the shed blood is desirable whenever possible. For patients with active blood loss but stable hemodynamics, VATS can be used to locate and stop the bleeding, evacuate blood clots, and break down adhesions.

Empyema

Treatment of empyema depends on the severity of the infection and the patient’s underlying condition. Some patients with empyema can be treated with serial thoracentesis, but most will require continuous drainage with a chest tube (see Fig. 10-5). Thoracoscopic decortication represents definitive therapy for severe cases. Usually, diagnostic thoracentesis is performed first to assess the fluid for signs of infection. Thick pus on thoracentesis, positive Gram stain, fluid glucose level lower than 60 mg/dL, pH less than 7.20, or elevated lactate dehydrogenase is associated with infection and an effusion that requires chest tube drainage. Once an empyema is detected, therapy should not be delayed because the fluid can quickly become loculated. Generally, the tube is left in place until the pleural drainage fluid becomes clear yellow and accumulates less than 150 mL in 24 hours. An empyema that fails to resolve on chest radiography within 48 hours requires chest CT and a careful review of antibiotic choice. Multiloculated effusions are best managed by thoracoscopic decortication.

Contraindications

For unstable trauma patients with a pneumothorax or hemothorax, there are no absolute contraindications to tube thoracostomy. In critical patients, placement of a chest tube is often performed empirically. In stable patients, relative contraindications include anatomic problems such as the presence of multiple pleural adhesions, emphysematous blebs, or scarring. Coagulopathic patients should be evaluated for replacement of clotting factors before any invasive procedure.

Treatment

Treatment of a Possible Tension Pneumothorax in an Unstable Patient

Immediate decompression of the chest must be considered in all injured patients with unexplained hypotension or tachypnea, particularly those with penetrating chest injuries. The goal is to open the pleural space quickly to allow any accumulated air to escape and decompress the chest cavity. This can be accomplished with a scalpel and forceps, as is done at the beginning stages of a thoracostomy (Fig. 10-9), or more commonly, decompression can be achieved with a large-bore needle/angiocatheter combination (minimum of 16 gauge) (Fig. 10-10). Place the catheter in the second intercostal space at the midclavicular line on the side with diminished breath sounds or on both sides if the diagnosis is unclear. Remove the needle, but leave the angiocatheter in place to create a simple pneumothorax. Regardless of whether this is successful in improving the patient’s vital signs, perform a standard tube thoracostomy immediately following the decompression. If the needle decompression is not effective, an open thoracostomy can be started, even without the immediate availability of a chest tube, to help create an exit for the air so that the patient’s respiratory and cardiovascular function can normalize.

Figure 10-9 Emergency pleural decompression. During resuscitation of a patient with a tension pneumothorax, there may be no time for a chest tube, and needle decompression may not be effective rapidly enough. Under these circumstances, the pleural cavity can be vented in seconds. This assumes that the patient is intubated.

Figure 10-10 Needle decompression. A large-bore needle/catheter combination is used to puncture the parietal pleura and establish the presence of blood or air in the pleural space. The needle can be placed anywhere in the pleural space, but traditionally at the same sites used for tube thoracostomy: the anterior second intercostal space in the midclavicular line or the anterior axillary line in the fourth or fifth interspace. The needle is placed so that it enters over the rib to avoid neurovascular injury. The needle is then withdrawn while leaving the catheter behind to create a simple open pneumothorax. The procedure can be done either with or without the syringe attached to the catheter. This is only a temporary therapeutic maneuver for a tension pneumothorax, and a chest tube must also be inserted.

Prehospital Treatment

Emergency needle decompression thoracostomy may be used in the prehospital setting or when a patient suspected of having a pneumothorax rapidly deteriorates or is initially seen in extremis. In such cases, attach the needle (or catheter) to a one-way (Heimlich) valve, underwater seal, or even a flutter valve (fashioned from the fingers of a surgical glove) so that the air can continue to escape during expiration but cannot enter during inspiration.

When a patient has an open chest wound in the prehospital setting, use a three-sided occlusive dressing to cover the wound. Similar to the one-way valve mechanisms, this dressing also acts as a one-way valve to allow air to escape but prevents air from entering the chest cavity. Use a sterile dressing, such as petrolatum-impregnated gauze, that extends 6 to 8 cm beyond the wound in all directions. Tape down only three sides of the dressing. Instruct the patient to deeply inhale, perform a Valsalva maneuver, or cough while you place the dressing.

Emergency Department Treatment

Equipment

The standard instruments for a tube thoracostomy tray are listed in Box 10-3 and depicted in Review Box 10-1. The most basic needs are a scalpel, a large (Kelly) clamp, and the thoracostomy (chest) tube.

Thoracostomy tubes are clear plastic tubes of various diameter that are open at both ends (Fig. 10-11). There is a radiopaque strip along the length of the tube that is interrupted by a series of holes along the distal length of the tube. The strip allows visualization of the tube’s location on the postprocedure radiograph and ensures that the side ports are within the pleural cavity. Tube sizes vary from 12 to 42 Fr, with smaller tubes being used for smaller pneumothoraces and larger (a minimum of 36 Fr) tubes for hemothorax and empyema. For pediatric patients, 14-, 16-, 20-, and 24-Fr tubes are adequate.

Figure 10-11 Thoracostomy tube.

Procedure

Conduct the procedure as sterilely as possible and wear a gown, glove, mask, and goggles. When possible, obtain consent.

Tube Insertion Site

Insert the tube over the top of the rib rather than near the bottom to avoid the neurovascular structures located on the inferior aspect of the ribs. The most common location for a chest tube is the midaxillary to anterior axillary line, usually in the fourth or fifth intercostal space (Fig. 10-12). This approach is cosmetically preferable and better tolerated than the anterior chest wall approach in the second intercostal space of the midclavicular line. The fifth intercostal space is approximately at the level of the nipple or the inferior scapular border in most patients, although the position of the female breast mass leads to variance. To avoid penetrating the abdominal cavity, choose a more superior insertion site because the external landmarks can be misleading. The diaphragm of a supine patient who is not taking a deep breath is much higher than expected.

Figure 10-12 Entry sites for tube thoracostomy. The second intercostal space, midclavicular line, is the preferred site for needle aspiration or catheter insertion (A). To find the second intercostal space, first palpate the sternomanubrial joint. The second rib articulates with this structure. The second intercostal space is found below the second rib. The fourth or fifth intercostal space, midaxillary to anterior axillary line (lateral to the pectoralis muscle and breast tissue), is preferred for a chest tube (B). The fifth intercostal space is usually at the level of the nipple. In an obese woman an assistant has to retract the breast upward to identify landmarks and avoid low placement.

Hold the tube next to the chest wall with the tip of the tube at the level of the clavicle to estimate the distance that the tube needs to be advanced from the incision site to the apex of the lung. Place a clamp on the tube to mark the maximum length that the tube should be inserted to prevent the tube from advancing too far. Confirm that the last drainage hole is within the pleural space at the level of the insertion site to ensure that the tube has been advanced sufficiently far. In markedly obese patients, it is common to fail to advance the tube far enough, with the last hole being left in fatty tissue rather than in the pleural space.

Patient Preparation

If indicated clinically, start oxygenating and monitoring the patient continuously with cardiac and pulse oximetry. When possible, elevate the head of the bed 30 to 60 degrees (Fig. 10-13) to lower the diaphragm and decrease the risk for injury to the diaphragm, spleen, and liver. Abduct the arm on the affected side, place it over the patient’s head, and restrain it in that position. Clean the skin with a standard surgical scrub and drape the field with sterile towels.

Figure 10-13 To insert a chest tube, position the patient semi-erect with the ipsilateral arm abducted as far as possible and preferably restrained. Supplemental oxygen and monitoring are recommended.

Anesthesia

Tube thoracostomy can be extremely painful, so give parenteral analgesics or procedural sedation to stable patients before the procedure. A common problem is inadequate systemic analgesia and local anesthesia. Use generous local anesthesia, such as up to 5 mg/kg of locally injected 1% lidocaine with or without epinephrine. Slowly inject local anesthetic over the superior aspect of the rib; through the muscle, periosteum, and parietal pleura; and along the entire anticipated tract of passage of the tube (Fig. 10-14). Intermittently aspirate for air or fluid with the needle to find the pleural cavity. If air or fluid is not found, change the insertion site.

Figure 10-14 Local anesthesia is essential to reduce the pain from insertion of a chest tube. Both the skin and pleura should be infiltrated with a generous amount of local anesthetic. A, The anesthetic is first infiltrated over the rib at the site of the incision. B, The needle is then advanced slowly over the top of the rib while intermittently infiltrating and aspirating until the pleura is breeched and air is withdrawn. Anesthetic is then injected liberally (maximum of 5 mg/kg of lidocaine) to cover the pleural lining. (A and B, Redrawn from Hughes WT, Buescher ES. Pediatric Procedures. 2nd ed. Philadelphia: Saunders; 1980:234.)

Once the tube is in place, administer local anesthetic through the chest tube into the pleural space to reduce pain caused by the tube rubbing against the pleura. In a stable patient, add 10 mL of 0.5% bupivacaine through the chest tube while the patient is lying on the contralateral side.¹⁹ After 5 minutes without drainage of the thorax, reinitiate standard gravity or vacuum drainage. Use parenteral analgesic agents as needed to control pain.

Insertion

The incision site should be lateral to the edge of the pectoralis major and breast tissue and not through these structures. A common problem is that the skin incision is too short to create and maintain an adequate tract to insert the thoracostomy tube. Make sure that the incision is no less than 3 to 5 cm long (Fig. 10-15, step 1). Make a transverse incision through the skin and subcutaneous tissue with a No. 10 blade over the rib. Some authors advocate making the initial skin incision over a rib lower than the intended intercostal space through which the tube will enter and then “tunneling” the tube under the skin and up over the next rib. This is theoretically done to prevent air leaks, but there is no good evidence to support this practice. It is more common to simply make the incision so that there is a straight path to the pleural cavity, but over the appropriate rib. This avoids the problem of losing the entrance point or increasing damage to soft tissue, both issues in obese patients. After the incision is made, insert a large Kelly clamp to push and spread the deeper tissues. Bluntly dissect a tract over the rib while avoiding the intercostal vessels and nerve on the inferior margin of each rib (Fig. 10-16; also see Fig. 10-15, step 2). Firm resistance will usually be felt when the tough parietal pleura is met. Close the clamp and push it forward with firm pressure to penetrate the pleura and enter the cavity. Considerable force may be needed. To prevent the clamp from penetrating too deeply, hold it at the midshaft a few centimeters distal to the incision and rest the tip against the pleura before pushing through (Fig. 10-17). Penetrating the pleura is usually the most painful portion of the procedure, so consider injecting extra anesthetic or analgesic at this point. On entering the pleural cavity, a palpable pop may be felt and a rush of air or fluid may occur. With only the tips of the clamp in the pleural cavity, spread the clamp to make an adequate hole in the pleura and then withdraw it (see Fig. 10-15, step 3). Make the opening in the parietal pleura wide enough to comfortably insert both a finger and the tube, but avoid a larger pleural opening to reduce the risk for an air leak (Fig. 10-18).

Figure 10-15 Tube thoracostomy. (From Custalow CB. Color Atlas of Emergency Department Procedures. Philadelphia: Saunders; 2005.)

Figure 10-16 Direct the Kelly clamp over the top of the rib to avoid the intercostal neurovascular bundle that courses along the inferior portion of the rib. Do not use excessive tunneling. (From Millikan JS, Moore EE, Steiner E. Complications of tube thoracostomy for acute trauma. Am J Surg. 1980;140:739.)

Figure 10-17 A and B, Use the right hand to push the clamp through the pleura (white arrows). Firmly encircle the midportion of the clamp with the fingers of the left hand to serve as a safety stop measure to avoid penetrating too deeply.

Figure 10-18 Right-sided subcutaneous emphysema after chest tube placement secondary to making too large a hole in the pleura with a subsequent air leak (arrows). It is usually benign and self-limited, but with positive pressure ventilation, it can be problematic. Because there is no way to close the pleura, making just the right-sized hole is the key to success.

Another common problem occurs at this point, particularly in obese patients: the dissected tract and pleural opening can be lost when the clamp is withdrawn. To prevent this problem, slide a sterile gloved finger over the clamp and into the pleura before withdrawing the clamp (Fig. 10-19). This is done to further define the tract and to verify that the pleura has been entered and that no solid organs have been penetrated. Whenever possible, leave the finger in the pleural space so that the hole is not lost (see Fig. 10-15, step 4) and then pass the tube over, under, or beside the finger into the pleural space, with the fingertip being used to guide the course of the tube (Fig. 10-20). This step allows the clinician to feel the tube passing into the pleural cavity, avoids subcutaneous dissection by the tube, and enhances proper direction of the tube. Pass the tube alone or hold onto a large curved clamp with the tip of the tube protruding beyond the tip of the clamp (Fig. 10-21; also see Fig. 10-15, step 5). Normally, the tube should pass with little resistance. If resistance is met, the tube may not be in the pleural cavity and instead is passing subcutaneously, is in a fissure, or is abutting against the mediastinum (Fig. 10-22). Still using the finger that remains in the pleural space, direct the tube posteriorly, medially, and superiorly until the last hole of the tube is clearly in the thorax, the marker clamp that was previously attached touches the chest wall, or resistance is felt (see Fig. 10-14, step 6). Ensure that all the holes in the tube are within the pleural space. Rotate the tube 360 degrees to reduce the likelihood of kinking.

Figure 10-19 After puncturing the pleural lining and spreading with the clamp, slide a gloved finger over the clamp to ensure that the pleural space has been reached and that no solid masses are present. Then withdraw the clamp and use the finger as a guide for the chest tube to ensure entry into the pleural cavity.

Figure 10-20 Leave your finger in the pleural space and use it to guide the course of the tube.

Figure 10-21 Hold the tube with the tip of the tube protruding beyond the tip of the clamp to reduce the risk for pulmonary injury.

Figure 10-22 Subcutaneous placement of a chest tube (arrows) can occur because the tube can dissect through tissue planes with relative ease. If this tube had been directed posteriorly, the radiograph would erroneously “confirm” intrapleural placement despite the tube being subcutaneous throughout its entire course. A computed tomography scan would settle the issue of a misplaced tube.

Attach the tube to the previously assembled water seal or suction before releasing the clamp. Ask the patient to cough and look for bubbles in the water seal chamber to check for patency of the system.

Confirmation of Tube Placement

There are many ways to confirm the location of the tube. Slide a finger along the tube to verify that it has entered the pleural cavity. Look for condensation on the inside of the tube and listen for air movement, which is audible during respirations. Observe free flow of blood or fluid. Check to be sure that the tube rotates freely after insertion. A chest radiograph is used for definitive assessment of tube placement (Fig. 10-23). If the tube and most proximal hole are not completely within the pleural space and if the field has remained sterile, advance the tube. If the tube is kinked or dysfunctional or the sterile field has been lost and advancement is required, place a new tube in sterile fashion through the same tract. If the tube has been advanced too far, simply withdraw it to the correct depth.

Figure 10-23 Definitive assessment of chest tube placement is with a chest radiograph. This patient has two chest tubes in place, and the radiopaque marking lines on the tubes (large arrows) are readily visible. Chest tubes are manufactured so that these radiopaque lines are interrupted at the level of the last drainage hole (small arrows). The gap in the line must be within the pleural cavity on the radiograph to ensure that the tube has been placed deep enough.

Securing the Tube

Once the position of the tube has been verified with a radiograph, secure it. There are numerous methods to secure a tube. The usual one is to sew the tube to the skin with large 0 or 1-0 silk or nylon sutures. Nylon sutures are acceptable but must be tied tightly or they will slip on the surface of the tube. One common method is to use a “stay” suture in which the same suture that closes the skin incision is used to hold the tube (Fig. 10-24, plate 1). After this suture is used to close the skin incision at the site of insertion of the tube, wrap the ends tightly and repeatedly around the chest tube and tie it securely. Tie the sutures tightly enough to indent the chest tube slightly and avoid slippage. If the skin incision is especially long, use additional simple sutures to close it completely.

Figure 10-24 Methods of securing a thoracostomy tube.

Another optional suture technique can both help close the skin around the tube and completely close the incision once the chest tube is removed. To do this, place a horizontal mattress suture approximately 1 cm across the incision on either side of the tube, essentially encircling it (Fig. 10-24, plate 2). Secure it with a simple knot that can easily be untied so that it can be opened and retied to close the incision after the tube has been removed.

After suturing the tube in place, apply an occlusive dressing of petrolatum-impregnated gauze at the point where the tube enters the skin to help reduce air leaks. Cover the skin with two or more gauze pads with a Y-shaped cut from the middle of one side to the center (Fig. 10-24, plate 3). Secure this dressing with wide (8- to 9-cm) cloth or elastic adhesive tape with or without benzoin.

Use approximately 10 to 12 cm of tape split into three pieces and extending halfway along its length. Place the two outside pieces on the skin on either side of the tube site, and wrap the center section tightly around the tube (Fig. 10-24, plate 4). Repeat this with a second piece of tape placed at a 180-degree angle to the first. Also securely tape the tube connections. To further secure the tube, use tape to create a loop or stalk by wrapping it around the tube. Then press the tape together for 1 to 2 cm before applying the tape to the chest wall (Fig. 10-24, plate 5).

Drainage and Suction Systems

A basic understanding of chest tube drainage systems is necessary to prevent life-threatening complications associated with their use. All drainage systems have two essential components: a one-way valve to allow air or fluid to drain out of the pleural space without allowing air back into the pleural space and a suction mechanism to increase the rate of drainage. The simplest drainage device is just a one-way valve without suction. This can be accomplished with either an underwater seal or a flutter (Heimlich) valve attached to the end of the chest tube (Fig. 10-25). Normal respiration and coughing are often sufficient to create the pressure necessary to remove excess air from the pleural space and allow the lung to expand. The Heimlich valve does not require suction and can be used for outpatient therapy.

Figure 10-25 Pleural drainage devices. A, A one-way Heimlich valve alone is often sufficient to treat a pneumothorax, but it cannot be used to treat a hemothorax. B, Disposable water seal chest drain set.

With a one-bottle underwater seal system, the intrapleural fluid or air exits under a small amount of water. It collects in the single reservoir and mixes with the water (Fig. 10-26A). The water above the tube acts as a seal because it is too heavy to be drawn back into the chest. For drainage to occur, intrathoracic pressure must be greater than the water pressure at the distal end of the immersed tube. This pressure is determined by the height of the water above the exit port of the tubing. When the height is too great (the tube is too deep in the water), even coughing may not raise intrapleural pressure sufficiently to drain the chest. Place the collecting bottle below the patient, usually on the floor, to prevent inspiration from generating enough negative pressure to pull the contents of the collection bottle into the chest cavity.

Figure 10-26 A, A single-bottle (water seal) collection device. B, A two-bottle system. The trap reservoir proximal to the water seal keeps the accumulating drainage from affecting the water seal pressure. C, This has now been replaced by a disposable system that mimics the two-bottle system. (Courtesy of Thora Klex System, Davol, Inc., Warwick, Rhode Island)

Use suction initially to treat patients with pneumothorax or hemothorax, but replace it with a water seal once drainage and expansion are satisfactory and no persistent air leaks are present. The suction device should have high suction flow (≤20 L/min) and be able to keep the suction constant. Wall suction of 10 to 20 cm H₂O is normally used, but the amount of suction in the chest tube depends on the depth of water in the water seal reservoir, not on the suction from the wall valve. When negative pressure from the suction source exceeds the depth of the water in the chamber, air enters from the top of the third tube and causes continuous bubbling (see Fig. 10-26B). This prevents a further increase in pressure in the chest tube. The wall suction dial can be turned down until only occasional bubbling can be detected. Vigorous bubbling does not equate with more suction.

The bottle combinations example is provided to illustrate the principles but is rarely used now. Many types of commercial, enclosed systems are available that essentially combine a two-bottle method that can be connected to suction, but with the addition of an “air leak chamber” (see Fig. 10-26C). Bubbling in this chamber indicates the presence of an air leak, usually from the drainage system itself as a result of a loose tube connection. If bubbling is present, first check the drainage system, tube, and connectors for any problems or loose connections. If the leak continues, check whether all the holes of the chest tube are within the thorax. If the bubbling continues after these steps, a continued air leak may be due to a large hole in the lung parenchyma, which is usually seen only with expiration or with coughing. A continuous air leak or a leak during inspiration indicates a larger and possibly more significant lung injury.²⁰ Surgical intervention is indicated if an air leak persists for longer than 72 hours or if the lung is not completely reexpanded.

The drainage reservoir must remain below the level of the chest to prevent the fluid in the collection system from reentering the chest. Place the reservoir on the floor or hang it from the edge of the bed. Simple respirations do not generate enough negative intrathoracic pressure to pull the water in the reservoir up to the height of the chest if the reservoir is kept on the floor and the patient is either sitting or lying at standard chair or bed height. The length of the tubing should be long enough so that the reservoir can be kept below the level of the patient, but not long enough to cause it to form dependent loops of fluid or kinks. Dependent loops collect fluid and create an additional water seal that if large enough, can require greater intrapleural pressure to drain. If these pressures become high enough (15 to 25 cm H₂O), a tension pneumothorax may result.

When the drainage system is functioning properly, the height of the fluid level in the drainage tube fluctuates with inspiration and expiration. Absence of respiratory fluctuation or a decrease in drainage may indicate that the system is blocked or that the lung is fully expanded. If the tube is blocked, the chest tube or collecting tubing, or both, can be changed or “stripped” to dislodge clots. Replacing the tube is a complicated process associated with risks, but the stripping procedure is controversial because of concern that the potentially high negative pressure from the procedure could damage lung tissue.²¹ For stripping, clamp the tube proximally and progressively compress it distally and then release it to allow the tube to spring open. The sudden increase in negative pressure may extract clots and fluid from a more proximal location. If the blockage is within the thorax, the tube can be cleared by forcing air or fluid back into the chest. The tube must be clamped distally and then compressed and stripped to force the contents proximally.

Perform occlusive clamping of a chest tube only with close monitoring because a tension pneumothorax can result in rare cases. Patients with chest tubes in place are best transported with a Heimlich valve or water seal only, not with the tube clamped. Avoid clamping the chest tube as a trial maneuver before removing it.

Prophylactic Antibiotics

The use of prophylactic antibiotics after placement of a chest tube in the emergency department (ED) is common, but no specific standards exist. It appears reasonable to provide short-term antibiotic prophylaxis since analyses of many studies have shown that antibiotics reduce the incidence of chest tube-associated empyema or pneumonia.²² Guidelines from the Eastern Association of Surgeons of Trauma recommend the use of first-generation cephalosporins during the first 24 hours for patients undergoing chest tube drainage for hemothorax.²³

Tube Removal

Chest tubes are rarely removed by emergency clinicians. The usual indication for removal of a chest tube is after a chest radiograph demonstrates complete resolution of the pneumothorax and there is no evidence of an ongoing air leak. Before removal, discontinue suction and establish a water seal. The literature is not clear about the use of a chest radiograph after suction is discontinued and after pulling the tube. Textbooks continue to recommend such practice, but studies have show that it is not necessary for postoperative patients.24,25

To remove the chest tube, ask the patient to sit upright at about a 45-degree angle. Use sterile technique, clean the skin, and drape the insertion site. Suturing equipment is needed to close the wound after the tube is removed except when a pursestring suture was placed at the time of insertion, in which case only sterile scissors are needed to cut the suture. Keep additional equipment available to reinsert a chest tube if the lung collapses. Prepare a petrolatum- or antibiotic-impregnated gauze dressing to cover the wound.

If a purse-string suture was placed previously, loosen it and prepare it for closing the wound. Cut the skin loop of the suture holding the tube to the skin and remove it from the skin. With the tube clamped, it has traditionally been advised to ask the patient to inhale fully and perform a mild Valsalva maneuver. Although this is theoretically beneficial in minimizing residual air following tube removal, it is of no proven value and many clinician use no special protocols for removal of the tube. Pull the tube out in one swift motion. Quickly tie the purse-string suture or suture the wound closed, and then cover it with an occlusive dressing. If no purse-string suture is present, once the tube is removed, suture the skin as quickly as is prudent for the physician. Observe the patient for 2 to 6 hours and obtain a chest radiograph before discharge. Any increase in symptoms requires prompt reevaluation. After 48 hours the patient may remove the dressing. Remove the sutures in 7 to 10 days.

Other Techniques

Small-Bore Tube Thoracostomy

Since the advent of common pleural drainage techniques in the early 20th century, physicians have preferred large-bore pleural drainage catheters (PDCs) inserted via blunt dissection for thoracic drainage and decompression. This preference for tubes greater than 16 Fr in diameter was born largely of concern for fibrin blockage, inadequate drainage capability, and the perception of frequent dislodgement of small-bore PDCs. To date, no quality randomized clinical trials have compare the use of large- versus small-bore PDCs, mainly because of the difficulty of conducting comparative studies in critically ill patients.

Despite these impediments, recent studies have hinted at the adequacy of small-bore PDCs for the treatment of many conditions. Review of the data available suggests that the rate of blockage and dislodgement is similar with large- and small-bore PDCs and that drainage capability is comparable in all but the most extreme circumstances.26–29 Another study has shown that large-bore PDC placement is associated with significantly more pain and slightly increased rates of empyema.³⁰

Review of the current pulmonology and critical care literature reveals no consensus on the appropriate use of small-bore PDCs; however, recent review articles have attempted to establish rough guidelines for their use. The current literature suggests that patients with malignant effusion, simple pneumothorax without penetrating injury, or a suspected air leak, as well as those with simple or complex parapneumonic effusions, are good candidates for small-bore PDCs. Patients with empyema, penetrating injury, traumatic hemothorax, or complex pneumothorax and those on mechanical ventilation require large-bore PDCs because of the potential for large-volume air leaks in such patients and the need for rapid evacuation of the pleural space.31,32

Many protocols are available for use of catheter aspiration as the first step in treating simple pneumothoraces. In general, patients with successful aspiration are observed in the ED for 4 to 6 hours after catheter insertion, and if a repeated radiograph shows no reaccumulation of air, the catheter is removed. After 2 more hours, another chest radiograph is obtained, and the patient is released if there is no recurrent pneumothorax. Patients with continued residual pneumothorax often receive a conventional chest tube.

Guidewire Technique for Catheter Aspiration

Catheters designed specifically for aspirating a pneumothorax are made of flexible, thrombosis-resistant radiopaque material with multiple distal side ports to reduce the risk for occlusion. Commercially available small-bore catheter systems are ideal for this procedure.

The catheters are placed via a standard “over-the-wire” (Seldinger) technique. The most common insertion site is the second intercostal space in the midclavicular line, but either of the standard locations (the midaxillary to anterior axillary line, usually in the fourth or fifth intercostal space, or the midclavicular line, second intercostal space) can be used. Place the patient in a semi-upright position. Clean the skin with an antiseptic solution and drape the area. Infiltrate locally with lidocaine for anesthesia. Advance the guide needle in a straight line at a 60 degrees angle cephalad over the top of the rib (Figs. 10-27 and 10-28). Unless a straight tract is created, it will be difficult to advance the floppy catheter, so a tunneling approach cannot be used. When the pleural space is identified by intermittent aspiration, halt advancement of the needle. Feed a guidewire through the needle and into the pleural space. Remove the needle while stabilizing the guidewire to keep it in the pleural space. Make a small incision in the skin with a No. 11 blade at the base of the wire to allow passage of the catheter through the skin. Some systems use a dilator over the wire to open the path through the soft tissue. Then thread the minicatheter over the guidewire and into the pleural space. Remove the wire and dilator while leaving the catheter in the pleural space. Advance the catheter through the subcutaneous tissue with a twisting motion. Secure the catheter to the skin with a suture and dress the incision site. The catheter may be removed after a period of observation, or suction may be maintained for a few days. If the catheter becomes clogged with mucus or blood, inject sterile saline through the device to clear it.

Figure 10-27 Aspiration of a pneumothorax with an Arrow 14-French Percutaneous Cavity Drainage Catheterization Kit. This 23-cm pigtail multihole catheter is ideal for such purposes. Air can be aspirated from the catheter with a syringe, or the catheter can be attached to suction or a Heimlich valve. This catheter is not used for patients on a ventilator, those with continuing air leaks, or those with a hemothorax. It is ideal for stable patients who have a primary pneumothorax or a collapse that can be expected to be stable if the lung is reexpanded (such as induced by intravenous drug use, minor blunt trauma, or insertion of a central venous catheter). If used for a few days, the catheter will become clogged with mucus or blood, which may be cleared by injecting sterile saline through the device.

Figure 10-28 Catheter-over-the-needle technique for aspiration of a pneumothorax.

To aspirate the pneumothorax, attach a three-way stopcock to the catheter and slowly aspirate air with a 60-mL syringe until resistance is felt. Gentle wall suction can also be used because a number of aspirations may be required until all the air exits. Take a chest radiograph to determine whether the lung is fully expanded. If residual pneumothorax is present, attempt further aspirations. If the residual pneumothorax persists and air cannot be aspirated, the catheter may be kinked or blocked with soft tissue. To relieve the blockage, place the patient in the full upright position and have the patient cough or take a deep breath. Alternatively, the catheter can be twisted or rotated gently.

Tube Thoracostomy in Pediatric Patients

Pneumothoraces can occur in the neonatal population. They are often associated with resuscitative measures (such as mechanical ventilation) for meconium aspiration or prematurity. For the rest of the pediatric population, trauma is the most common cause. A pneumothorax will develop in approximately one third of children with thoracic trauma. As in adults, physical examination of newborns and infants with pneumothorax can be highly variable, thus necessitating the use of a chest radiograph for diagnosis. Ideally, both anteroposterior and cross-table lateral projections are used because small pneumothoraces may be seen only on the lateral view. A chest CT is more sensitive and specific.

In general, tube thoracostomy is the treatment of choice once a symptomatic pneumothorax is detected in infants. When signs of tension pneumothorax are present, immediately aspirate with a plastic catheter-over-the-needle device. Small pneumothoraces (<20% of the hemithorax) in relatively asymptomatic infants (e.g., those without other problems who do not require positive airway pressure) can be observed.

The technique of tube thoracostomy in pediatric patients is essentially the same as that in adults, but the body size and small spaces between the ribs make the procedure more difficult. The size of the tube increases with the patient’s weight, starting with 8- to 10-Fr catheters for premature infants (Table 10-1). Because of the risk for future breast deformities, avoid the midclavicular approach. Instead, use the anterior axillary line through the fifth intercostal space for newborns and infants.³³

TABLE 10-1

Approximate Pediatric Chest Tube Size by Weight

Complications

The most common complications include infection, laceration of an intercostal vessel, laceration of the lung, and intraabdominal or solid organ placement of the chest tube (Boxes 10-4 and 10-5). Local infection at the insertion site is common and often related to the emergency nature of the procedure. Subcutaneous emphysema is a frequent, usually benign complication that is self-limited and generally caused by an excessively large opening in the pleura. Subcutaneous air may be a result of the incident that caused the pneumothorax in the first place. The development of palpable subcutaneous air is another complication of chest tube placement. It is usually limited to the insertion site but can become massive with PPV in a patient with continued air leak or an occluded tube.

Intercostal arteries or veins may be lacerated, but this can be minimized by using blunt dissection and carefully directing the tube just above the rib. The tube may adequately tamponade such bleeding. If the bleeding persists, extend the incision to ligate the bleeding vessel. If the bleeding continues, consult a thoracic surgeon.

Failure of a pneumothorax to reexpand may be due to a mechanical air leak, but it may also indicate a bronchopleural fistula, a continued parenchymal lung leak, or a bronchial injury. Tension pneumothorax can occur if a blockage in the drainage system at any point is associated with a continued air leak from the lung. Reinsertion or placement of a second tube may be indicated if the first tube is not functioning properly. In general, if a chest tube is not functioning properly and the patient is deteriorating, remove the tube and insert another one. Manipulating the tube by pushing it deeper into the chest cavity can lead to an increased risk for infection.

A rare complication of tube thoracostomy is unilateral reexpansion pulmonary edema. The pulmonary edema ranges from mild to severe, but fatalities have been reported.³⁴ The condition may occur shortly after reexpansion or may be delayed a number of hours. A common factor in these cases seems to be a prolonged period between the development of a pneumothorax and the onset of treatment, but the exact time frame is quite variable. Usually, the pneumothorax has been present for at least 3 to 4 days. Proposed mechanisms include anoxic damage to the alveolar-capillary basement membrane from prolonged pulmonary collapse, loss of surfactant, or rapid fluid shifts. Treatment is supportive, with ventilatory support occasionally being required. Reintroduction of air back into the pleural space and temporary occlusion of the ipsilateral pulmonary artery have been other suggested, but unproved interventions.