TOC | Pulm

Spontaneous Pneumothorax
Steven A. Sahn, John E. Heffner  
NEJM March 23, 2000 -- Vol. 342, No. 12               See pneumothorax2001.pdf  

Classification of Pneumothorax

• Spontaneous (not caused by trauma or any obvious precipitating factor),
• Traumatic - Traumatic pneumothorax is caused by penetrating or blunt trauma to the chest, with air entering the pleural space directly through the chest wall; visceral pleural penetration; or alveolar rupture due to sudden compression of the chest.
• Iatrogenic - Iatrogenic pneumothorax results from a complication of a diagnostic or therapeutic intervention.
• Primary spontaneous pneumothorax occurs in persons without clinically apparent lung disease
• Secondary spontaneous pneumothorax is a complication of preexisting lung disease.

Primary Spontaneous Pneumothorax

Pathophysiology - subpleural bullae in most patients.

Clinical Presentation

• Ipsilateral pleuritic chest pain or acute dyspnea & tachycardia.
• Symptoms usually resolve within 24 hours, even if the pneumothorax remains untreated and does not resolve.
• Patients with a small pneumothorax (one involving <15 percent of the hemithorax) may have a normal physical examination. In patients with a larger pneumothorax, the findings on examination may include decreased movement of the chest wall, a hyperresonant percussion note, diminished fremitus, and decreased or absent breath sounds on the affected side. Tachycardia of more than 135 beats per minute, hypotension, or cyanosis should raise the suspicion of a tension pneumothorax. The results of arterial-blood gas measurement typically indicate an increase in the alveolar-arterial oxygen gradient and acute respiratory alkalosis.

Diagnosis

• it is suggested by the patient's history and is confirmed by posterior-anterior chest radiograph.

Recurrence Rate

• about 30 percent, range 16-52 %. Most recurrences occur within 6-24 months after the initial pneumothorax.

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Secondary Spontaneous Pneumothorax

It is a potentially life-threatening event, because patients with this condition have associated lung disease and limited cardiopulmonary reserve.

The major causes of secondary spontaneous pneumothorax :

• Airway disease: COPD, cystic fibrosis, status asthmaticus.
• Pneumonitis: as Pneumocystic carinii, necrotizing pneumonias.
• Interstitial lung disease: sarcoidosis, idiopathic pulm fibrosis, Langerhans's cell granulomatosis, etc.
• Connective tissue disease: RA, ankylosing spondylitis, polymyositis, scleroderma, Marfan's synd, Ehlers-Danlos synd.
• Cancer: lung cancer, sarcoma.
• Thoracic endometriosis (related to menses)

Chronic obstructive pulmonary disease and Pneumocystis carinii pneumonia related to infection with the human immunodeficiency virus (HIV) are the most common conditions associated with secondary pneumothorax.

Pneumothorax related to menses typically occurs in women who are 30 to 40 years old and who have a history of pelvic endometriosis. Such a catamenial pneumothorax usually affects the right lung and occurs within 72 hours after the onset of menses.  Since the rate of recurrence among women receiving hormonal treatment is 50 percent at one year, pleurodesis should be recommended.

Pathophysiology: - the ruptured alveolus.

Clinical Presentation

• Dyspnea, ipsilateral chest pain, severe hypoxemia or hypotension can occur and be life-threatening.
• Symptoms do not resolve spontaneously in patients with secondary spontaneous pneumothorax.
• The physical findings are often subtle and may be masked by the underlying lung disease, particularly in patients with chronic obstructive pulmonary disease. Pneumothorax should always be considered in a patient with chronic obstructive pulmonary disease in whom unexplained dyspnea develops, particularly in association with unilateral chest pain.

Diagnosis: Clinical symptoms & signs, chest x-ray or CT scan.

Recurrence: The rates of recurrence ranging from 39 percent to 47 percent.

Treatment
The management of pneumothorax centers on evacuating air from the pleural space and preventing recurrences.

Available therapeutic options include

• simple observation;
• simple aspiration with a catheter;
• insertion of a chest tube;
• pleurodesis with talc powder;
• thoracoscopy through a single insertion port into the chest;
• video-assisted thoracoscopic surgery (bullae resection); and
• thoracotomy.

The selection of an approach depends on the size of the pneumothorax, the severity of symptoms, whether there is a persistent air leak, and whether the pneumothorax is primary or secondary.

Reexpansion of the Lung

With a small primary spontaneous pneumothorax (one involving <15 percent of the hemithorax), patients may have minimal symptoms. Supplemental oxygen accelerates by a factor of four the reabsorption of air by the pleura, which occurs at a rate of 2 percent per day in patients breathing room air. Young patients who are likely to comply with treatment plans may be managed at home after six hours of observation in the emergency department if such patients can obtain emergency services quickly.

Primary spontaneous pneumothoraxes that are large (involving greater than or equal to 15 percent of the hemithorax) or progressive may be drained by simple aspiration with a plastic intravenous catheter, thoracentesis catheter, or small-bore (7 to 14 French) catheter or by the insertion of a chest tube. Simple aspiration is successful in 70 percent of patients with moderate-sized primary spontaneous pneumothorax. If the patient is more than 50 years old, or if more than 2.5 liters of air is aspirated, this method is likely to fail. Successfully treated patients can be discharged from emergency departments with follow-up within several days if a chest radiograph obtained six hours after aspiration shows resolution of the pneumothorax and if such patients can obtain emergency services quickly. If aspiration through a catheter fails to expand the lung, the catheter can be attached to a one-way Heimlich valve or a water-seal device and used as a chest tube.

Primary spontaneous pneumothorax may also be managed with a chest tube that is left in place for one or more days. Because air leakage is usually minimal, a small-bore (7 to 14 French) chest catheter usually suffices. The catheter can be attached to a one-way Heimlich valve, which allows ambulation, or to a water-seal device. Routine application of suction (with a pressure of 20 cm of water) has not been shown to improve the outcome. Drainage through a chest tube has a success rate of 90 percent for treatment of a first pneumothorax, but the rate decreases to 52 percent for treatment of a first recurrence and to 15 percent for treatment of a second recurrence. Large air leaks and pleural effusions that clog the catheter contribute to failure.

Secondary spontaneous pneumothorax should be managed with a chest tube (20 to 28 French) attached to a water-seal device, and patients should be hospitalized, because of the risk of respiratory compromise. Suction can be reserved for patients with ongoing air leaks and those in whom the lung fails to reexpand after drainage through a water-seal device.

Complications of chest-tube drainage include pain, pleural infection, incorrect placement of the tube, hemorrhage, and hypotension and pulmonary edema due to lung reexpansion.

Persistent Air Leaks

Persistent air leaks are more common with secondary pneumothorax than with primary pneumothorax.

Seventy-five percent of air leaks in primary spontaneous pneumothorax and 61 percent of air leaks in secondary spontaneous pneumothorax resolve after 7 days of chest drainage, but 100 percent and 79 percent, respectively, resolve after 15 days. Another study reported a lower likelihood of eventual resolution of air leaks that persist for longer than two days.

We reassure patients with a first primary spontaneous pneumothorax, at the time the chest tube is inserted, that surgery is usually unnecessary. However, surgery does become a consideration if an air leak persists for four to seven days. On the seventh day of an air leak, we discuss the available surgical alternatives with the patient. Most of our patients request surgical intervention after seven days of a persistent air leak.

or an initial secondary spontaneous pneumothorax, we recommend surgery for patients who are suitable candidates. It is important to prevent recurrences, regardless of the presence or absence of an air leak, because of the seriousness of this condition. Some centers, however, maintain drainage through a chest tube for two weeks before undertaking a surgical intervention.

Preventing Recurrences

We recommend interventions to prevent recurrence after the second ipsilateral pneumothorax. Some centers, however, recommend such measures for all patients with a first primary spontaneous pneumothorax. Patients who plan to continue activities that increase the risk that complications will result from a pneumothorax (e.g., flying or diving) should undergo preventive treatment after the first episode. We still caution against such activities, however, because of the risk of a contralateral pneumothorax.

Since most recurrences occur within three years of the first pneumothorax and risk decreases after the age of 40 years, younger patients are at risk for a longer period and have a greater likelihood of benefiting from preventive procedures after a first pneumothorax than older patients.

Interventions to Prevent Recurrences

The instillation of sclerosing agents through chest tubes in the absence of air leaks is associated with a recurrence rate of 8 to 25 percent, which is higher than the rate associated with other available methods.

Thoracoscopy through a single chest port performed under direct visualization allows the resection of small apical bullae (those approximately <2 cm in diameter) and pleurodesis by mechanical pleural abrasion or insufflation of talc. Two grams of talc is used, in contrast with the 5 g recommended for pleurodesis of malignant pleural effusions. The treatment of patients found at thoracoscopy to have bullae greater than or equal to 2 cm in diameter can be switched to video-assisted thoracoscopic surgery or thoracotomy (for the resection of bullae and pleurodesis). The success rate for thoracoscopy with insufflation of talc is approximately 97 percent, with a recurrence rate of 5 to 9 percent. There is concern about the use of talc, however, because of reports of acute lung injury and respiratory failure.

07192000

REF:  http://www.chestnet.org/education/cs/pneumothorax/qrg/page02.php

American College of Chest Physicians  -  Consensus Statements

Consensus Panel on the Management of Spontaneous Pneumothorax 2009  

Spontaneous pneumothorax that occurs in the absence of thoracic trauma is classified as primary or secondary:

1. Primary pneumothorax occurs in patients who have no clinically apparent lung disorder.
2. Secondary pneumothorax occurs in patients with an underlying pulmonary disease, most commonly chronic obstructive pulmonary disease (COPD).

Primary and secondary pneumothorax occurs in more than 20,000 patients annually in the United States.

Pneumothorax size Determined by distance from the lung apex to the ipsilateral thoracic cupola at the parietal surface as determined by upright standard radiograph.

• Small pneumothorax: < 3 cm apex-to-cupola distance
• Large pneumothorax: > 3 cm apex-to cupola distance

Stable patient

• All of the following present: respiratory rate <24/min, heart rate >60/min or <120 min, normal blood pressure. Room air O2 saturation >90%, and patient can speak in whole sentences between breaths.

Unstable patient

• Any patient not fulfilling the definition of stable.

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Primary Spontaneous Pneumothorax  

Clinically Stable Patients With a Small Pneumothorax (< 3 cm apex-to-cupola distance)

• Observe in emergency department for 3 to 6 hours and discharge home if repeat chest radiograph excludes progression of pneumothorax (Good Consensus).
  [Note: Patients may be admitted for observation if they live distant from emergency services or follow-up care is considered unreliable (Good Consensus).]
• Follow-up in 12 to 48 hours (Good Consensus). Repeat radiography to document resolution of pneumothorax (Very Good Consensus).
• Simple aspiration of the pneumothorax or chest tube insertion is not appropriate for most patients unless the pneumothorax enlarges (Good Consensus).

Clinically Stable Patients With a Large Pneumothorax (> 3 cm apex-to cupola distance)

• Re-expand the lung and hospitalize in most instances (Very Good Consensus).
• For lung re-expansion use small-bore catheter (<14F) or place a 16F to 22F chest tube (Good Consensus).
• Attach catheter or tube to a Heimlich valve or water seal device (Good Consensus) and leave in place until the lung expands against the chest wall and air leaks resolve. If the lung fails to expand quickly, apply suction to a water seal device. Alternatively, suction may be applied immediately after chest tube placement for all patients managed with a water seal system (Some Consensus).
• Reliable patients unwilling to be hospitalized may be discharged with a small-bore catheter attached to a Heimlich valve if the lung re-expanded after removal of pleural air (Good Consensus). Follow-up within 48 hours.

Clinically Unstable Patients With a Large Pneumothorax

• Hospitalize and insert a chest catheter to re-expand the lung (Very Good Consensus).
• For most patients, use a 16F to 22F standard chest tube or small bore catheter (<14F) (Good Consensus), depending on the degree of clinical instability.
• A 24F to 28F standard chest tube may be used if the patient requires positive pressure ventilation or is anticipated to have a large air leak (Good Consensus).
• A water seal device can be used without suction initially (Good Consensus), but suction should be applied if the lung fails to re-expand with water seal drainage.
• A small-bore catheter attached to a Heimlich valve may be used if clinical stability can be obtained with immediate evacuation of the pleural space (Good Consensus). Substitute the Heimlich valve with a water seal device and apply suction if the lung fails to re-expand (Good Consensus).

Chest Tube Removal

• Remove chest tube in a staged manner, to assure that the air leak into the pleural space has resolved (Good Consensus). The first stage requires a radiograph demonstrating complete resolution of the pneumothorax and no clinical evidence of an ongoing air leak. Discontinue any chest tube suction (Good Consensus).

The panel had divided opinion on the question "Should the chest tube be clamped to detect an air leak after re-expansion of the lung?"

• No (53%)
• Yes (47%), 4 hours after the last evidence of an air leak

The panel had divided opinion on the question: "When should chest radiography be repeated after the last evidence of an air leak to ensure that the pneumothorax has not recurred before the chest tube is removed?"

• 5 to 12 hours after the last evidence of an air leak (62%)
• <4 hours (10%), 13 to 23 hours (10%), 24 hours (17%)

Persistent Air Leak

• Continue observation for 4 days to assess for spontaneous closure of bronchopleural fistula. If an air leak persists longer than 4 days, evaluate the patient for surgery to close the air leak and perform a pleurodesis procedure to prevent pneumothorax recurrence (Very Good Consensus). Thoracoscopy is the preferred management procedure (Very Good Consensus).
• Use of an additional chest tube or bronchoscopy in an attempt to seal endobronchial sites of air leakage is not indicated (Very Good Consensus).
• Except in special circumstances where surgery is contraindicated or a patient refuses surgery, chemical pleurodesis should not be used in the management of most patients (Very Good Consensus). If chemical pleurodesis is performed, doxycycline or talc slurry are the preferred sclerosing agents (Good Consensus).

Prevention of Pneumothorax Recurrence

The panel had divided opinion on the question: "Should patients with their first primary spontaneous pneumothorax be offered an intervention to prevent recurrence?"

• Yes (15%)
• No (85%), except for patients with persistent air leaks, an intervention to prevent recurrence should be reserved for the second pneumothorax.

The occupational and recreational interests of patients (eg, flying, scuba diving) should be considered in timing an intervention.

Thoracoscopy is the preferred procedure for preventing pneumothorax recurrence (Very Good Consensus).
Thoracoscopy can be performed with or without video assistance. Intraoperative bullectomy should be performed (Very Good Consensus) by staple bullectomy (Very Good Consensus) in patients with apical bullae visualized at surgery.

Chemical pleurodesis through a chest tube is an acceptable alternative to thoracoscopy in certain patients (Good Consensus), although thoracoscopy has a higher success rate.
Intraoperative pleurodesis should be performed in most patients, with parietal pleural abrasion limited to the upper half of the hemithorax (Good Consensus).

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Secondary Spontaneous Pneumothorax

Clinically Stable Patients With a Small Pneumothorax

• Hospitalize the patient (Good Consensus) rather than managing the pneumothorax in the emergency department with observation or simple aspiration only (Very Good Consensus).
• Observe the hospitalized patient (Good Consensus), or treat with a chest tube (Some Consensus), depending on the extent of symptoms and course of the pneumothorax.
• Thoracoscopy should not be performed before the patient is stablized with a chest tube (Very Good Consensus).Clinically Stable Patients With a Large Pneumothorax
• Hospitalize the patient, and place a chest tube to re-expand the lung (Very Good Consensus).
• Thoracoscopy should not be performed before the patient is stablized with a chest tube (Very Good Consensus).

Clinically Unstable Patients With a Pneumothorax of Any Size

• Hospitalize the patient, and place a chest tube to re-expand the lung (Very Good Consensus).
• Thoracoscopy should not be performed before the patient is stable (Very Good Consensus).

Chest Tube Management

• Clinical circumstances dictate the size of chest tubes.
• Unstable patients (Very Good Consensus) and patients supported by mechanical ventilation at risk for large pleural air leaks (Good Consensus) require a 24F to 28F chest tube.
• Stable patients not at risk for large air leaks require a 16F to 22F chest tube (Good Consensus). A small-bore (<14F) catheter may be acceptable in certain circumstances, including small pneumothoraces and patient preference (Good Consensus).
• Attachment of the chest tube to a water seal device with (Some Consensus) or without (Good Consensus) suction is acceptable management for most patients. Patients treated with water seal alone should be managed with suction if the lung fails to re-expand (Good Consensus). A Heimlich valve may be used (Good Consensus), but a water seal device is preferred for most patients.

Prevention of Pneumothorax Recurrence

Most (81%) panel members recommend an intervention to prevent pneumothorax recurrence after the first pneumothorax because of the potential lethality of secondary pneumothoraces. The other 19% of panel members recommend an intervention to prevent recurrence after the second spontaneous pneumothorax.

Surgical management is preferred to prevent pneumothorax recurrence (Very Good Consensus); surgery has a lower recurrence rate than use of a sclerosing agent. Instillation of a sclerosant through a chest tube may be used in certain circumstances (Good Consensus) based on patients’ contraindications to surgery, management preferences, and underlying poor patient prognosis (see below for sclerosant choice).

Medical or surgical thoracoscopy is preferred (Very Good Consensus), but a muscle-sparing (axillary) thoracotomy is acceptable (Good Consensus).

Standard thoracotomy through a lateral or medial sternotomy is not appropriate for most patients (Good Consensus).

Bullectomy and a procedure to produce pleural symphysis should be performed during the surgical intervention. Staple bullectomy is preferred (Very Good Consensus). Parietal pleurectomy or parietal pleural abrasion limited to the upper half of the hemithorax is preferred to produce pleural symphysis in most patients (Good Consensus).

For producing pleural symphysis by instillation of a sclerosing agent through a chest tube, preferred agents are talc slurry (Very Good Consensus) and doxycycline (Good Consensus).

Assessment of Pulmonary Function

Performance of pulmonary function tests (PFTs) to assist management decisions is not appropriate (Perfect Consensus) for patients with secondary pneumothoraces. Expiratory maneuvers performed during the acute phase of a pneumothorax may produce inaccurate results. However, results from previous PFTs may assist in patient selection for an intervention to prevent pneumothorax recurrence in special circumstances (Good Consensus).

Persistent Air Leaks

• For a patient with persistent air leaks and prolonged chest tube drainage who initially refuses surgery, continue observation for 5 days. After 5 days of observation, the patient should be urged to accept surgical intervention. More prolonged delay may limit the effectiveness of thoracoscopy. Instillation of sclerosing agents through a chest tube to produce a pleural symphysis in managing persistent air leaks is acceptable for patients who are not surgical candidates (Good Consensus).

Chest Tube Removal

• For patients treated with a chest tube without referral for surgical intervention to prevent pneumothorax recurrence, management of chest tube removal is similar to management in patients with a primary pneumothorax.

Chest Imaging With CT

• Obtaining a chest CT scan is acceptable management for patients with pneumothorax recurrence (Good Consensus), during management of a persistent air leak (Some Consensus), and for planning a surgical intervention (Some Consensus).

           4-2009